From 8618e065c0d7a64b4303fa9dfe1892abfc115629 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 26 May 2025 16:50:29 +0200
Subject: [PATCH 01/44] bigan

---
 e2e/relay-additional-resolvers/package.json   |  9 +++
 .../relay-additional-resolvers.e2e.ts         | 31 ++++++++++
 .../services/posts.ts                         | 56 +++++++++++++++++++
 .../services/users.ts                         | 54 ++++++++++++++++++
 yarn.lock                                     | 10 ++++
 5 files changed, 160 insertions(+)
 create mode 100644 e2e/relay-additional-resolvers/package.json
 create mode 100644 e2e/relay-additional-resolvers/relay-additional-resolvers.e2e.ts
 create mode 100644 e2e/relay-additional-resolvers/services/posts.ts
 create mode 100644 e2e/relay-additional-resolvers/services/users.ts

diff --git a/e2e/relay-additional-resolvers/package.json b/e2e/relay-additional-resolvers/package.json
new file mode 100644
index 000000000..e5b4dfb9e
--- /dev/null
+++ b/e2e/relay-additional-resolvers/package.json
@@ -0,0 +1,9 @@
+{
+  "name": "@e2e/relay-additional-resolvers",
+  "private": true,
+  "dependencies": {
+    "@apollo/subgraph": "^2.10.0",
+    "graphql": "^16.9.0",
+    "graphql-sse": "^2.5.3"
+  }
+}
diff --git a/e2e/relay-additional-resolvers/relay-additional-resolvers.e2e.ts b/e2e/relay-additional-resolvers/relay-additional-resolvers.e2e.ts
new file mode 100644
index 000000000..70d377164
--- /dev/null
+++ b/e2e/relay-additional-resolvers/relay-additional-resolvers.e2e.ts
@@ -0,0 +1,31 @@
+import { createTenv } from '@internal/e2e';
+import { expect, it } from 'vitest';
+
+const { gateway, service } = createTenv(__dirname);
+
+it('should resolve the data behind the node', async () => {
+  const { execute } = await gateway({
+    supergraph: {
+      with: 'apollo',
+      services: [await service('users'), await service('posts')],
+    },
+  });
+
+  await expect(
+    execute({
+      query: /* GraphQL */ `
+        {
+          node(id: "user-2") {
+            ... on User {
+              name
+              posts {
+                title
+                content
+              }
+            }
+          }
+        }
+      `,
+    }),
+  ).resolves.toMatchInlineSnapshot();
+});
diff --git a/e2e/relay-additional-resolvers/services/posts.ts b/e2e/relay-additional-resolvers/services/posts.ts
new file mode 100644
index 000000000..fd3557053
--- /dev/null
+++ b/e2e/relay-additional-resolvers/services/posts.ts
@@ -0,0 +1,56 @@
+import { createServer } from 'http';
+import { buildSubgraphSchema } from '@apollo/subgraph';
+import { Opts } from '@internal/testing';
+import { parse } from 'graphql';
+import { createYoga } from 'graphql-yoga';
+
+const posts: { id: string; title: string; content: string }[] = [
+  {
+    id: 'post-1',
+    title: 'Hello world',
+    content: 'This is a post',
+  },
+  {
+    id: 'post-2',
+    title: 'Hello again',
+    content: 'This is another post',
+  },
+  {
+    id: 'post-3',
+    title: 'Hello again again',
+    content: 'This is another post again',
+  },
+];
+
+const typeDefs = parse(/* GraphQL */ `
+  type Query {
+    hello: String!
+  }
+  interface Node {
+    id: ID!
+  }
+  type Post implements Node @key(fields: "id") {
+    id: ID!
+    title: String!
+    content: String!
+  }
+`);
+
+const resolvers = {
+  Query: {
+    hello: () => 'world',
+  },
+  Post: {
+    __resolveReference(post: { id: string }) {
+      return posts.find((p) => p.id === post.id);
+    },
+  },
+};
+
+const yoga = createYoga({
+  schema: buildSubgraphSchema([{ typeDefs, resolvers }]),
+});
+
+const opts = Opts(process.argv);
+
+createServer(yoga).listen(opts.getServicePort('posts'));
diff --git a/e2e/relay-additional-resolvers/services/users.ts b/e2e/relay-additional-resolvers/services/users.ts
new file mode 100644
index 000000000..dbcf214ff
--- /dev/null
+++ b/e2e/relay-additional-resolvers/services/users.ts
@@ -0,0 +1,54 @@
+import { createServer } from 'http';
+import { buildSubgraphSchema } from '@apollo/subgraph';
+import { Opts } from '@internal/testing';
+import { parse } from 'graphql';
+import { createYoga } from 'graphql-yoga';
+
+const users: { id: string; name: string; posts: { id: string }[] }[] = [
+  {
+    id: 'user-1',
+    name: 'John Doe',
+    posts: [{ id: 'post-2' }],
+  },
+  {
+    id: 'user-2',
+    name: 'Jane Doe',
+    posts: [{ id: 'post-3' }, { id: 'post-1' }],
+  },
+];
+
+const typeDefs = parse(/* GraphQL */ `
+  type Query {
+    hello: String!
+  }
+  interface Node {
+    id: ID!
+  }
+  type User implements Node @key(fields: "id") {
+    id: ID!
+    name: String!
+    posts: [Post!]!
+  }
+  type Post implements Node {
+    id: ID!
+  }
+`);
+
+const resolvers = {
+  Query: {
+    hello: () => 'world',
+  },
+  User: {
+    __resolveReference(user: { id: string }) {
+      return users.find((u) => u.id === user.id);
+    },
+  },
+};
+
+const yoga = createYoga({
+  schema: buildSubgraphSchema([{ typeDefs, resolvers }]),
+});
+
+const opts = Opts(process.argv);
+
+createServer(yoga).listen(opts.getServicePort('users'));
diff --git a/yarn.lock b/yarn.lock
index bef19b367..b072395f1 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3356,6 +3356,16 @@ __metadata:
   languageName: unknown
   linkType: soft
 
+"@e2e/relay-additional-resolvers@workspace:e2e/relay-additional-resolvers":
+  version: 0.0.0-use.local
+  resolution: "@e2e/relay-additional-resolvers@workspace:e2e/relay-additional-resolvers"
+  dependencies:
+    "@apollo/subgraph": "npm:^2.10.0"
+    graphql: "npm:^16.9.0"
+    graphql-sse: "npm:^2.5.3"
+  languageName: unknown
+  linkType: soft
+
 "@e2e/retry-timeout@workspace:e2e/retry-timeout":
   version: 0.0.0-use.local
   resolution: "@e2e/retry-timeout@workspace:e2e/retry-timeout"

From 9871737e949a8656b36c01feb7c8d478a71a08e1 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 26 May 2025 19:02:47 +0200
Subject: [PATCH 02/44] begin

---
 .../gateway.config.ts                         |  43 +++++
 e2e/relay-additional-resolvers/gw.out         | 173 ++++++++++++++++++
 e2e/relay-additional-resolvers/id.ts          |  20 ++
 .../relay-additional-resolvers.e2e.ts         |  28 ++-
 4 files changed, 261 insertions(+), 3 deletions(-)
 create mode 100644 e2e/relay-additional-resolvers/gateway.config.ts
 create mode 100644 e2e/relay-additional-resolvers/gw.out
 create mode 100644 e2e/relay-additional-resolvers/id.ts

diff --git a/e2e/relay-additional-resolvers/gateway.config.ts b/e2e/relay-additional-resolvers/gateway.config.ts
new file mode 100644
index 000000000..669a03551
--- /dev/null
+++ b/e2e/relay-additional-resolvers/gateway.config.ts
@@ -0,0 +1,43 @@
+import { defineConfig } from '@graphql-hive/gateway';
+import { decodeGlobalID } from './id';
+
+export const gatewayConfig = defineConfig({
+  additionalTypeDefs: /* GraphQL */ `
+    type Query {
+      node(id: ID!): Node
+      nodes(ids: [ID!]!): [Node]!
+    }
+  `,
+  additionalResolvers: {
+    Query: {
+      node(_source: any, args: { id: string }, _context: any, _info: any) {
+        const { type, localID } = decodeGlobalID(args.id);
+        return {
+          __typename: type,
+          id: localID,
+        };
+      },
+      nodes(_source: any, args: { ids: string[] }, _context: any, _info: any) {
+        return args.ids.map((id) => {
+          const { type, localID } = decodeGlobalID(id);
+          return {
+            __typename: type,
+            id: localID,
+          };
+        });
+      },
+      _entities: (_: any, { representations }: any) => {
+        return representations.map((ref) => {
+          // Since all our entities just need id, we can return the reference as is
+          // The __typename is already included in the reference
+          return ref;
+        });
+      },
+    },
+    Node: {
+      __resolveType(source: { __typename: string }) {
+        return source.__typename;
+      },
+    },
+  },
+});
diff --git a/e2e/relay-additional-resolvers/gw.out b/e2e/relay-additional-resolvers/gw.out
new file mode 100644
index 000000000..16295a523
--- /dev/null
+++ b/e2e/relay-additional-resolvers/gw.out
@@ -0,0 +1,173 @@
+[2025-05-26T14:55:36.564Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fshFt7ol/supergraph.graphql 
+[2025-05-26T14:55:36.566Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fshFt7ol/supergraph.graphql 
+[2025-05-26T14:55:36.566Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fshFt7ol/supergraph.graphql for changes 
+[2025-05-26T14:55:36.569Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fshFt7ol/supergraph.graphql 
+[2025-05-26T14:55:36.579Z] INFO   Listening on http://localhost:60575 
+[2025-05-26T14:56:42.380Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
+[2025-05-26T14:56:42.387Z] INFO   Loaded config 
+[2025-05-26T14:56:42.387Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsdxRzJ4/supergraph.graphql 
+[2025-05-26T14:56:42.388Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsdxRzJ4/supergraph.graphql 
+[2025-05-26T14:56:42.388Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsdxRzJ4/supergraph.graphql for changes 
+[2025-05-26T14:56:42.390Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsdxRzJ4/supergraph.graphql 
+[2025-05-26T14:56:42.397Z] INFO   Listening on http://localhost:60714 
+[2025-05-26T14:56:42.610Z] ERROR  Error: Query.node defined in resolvers, but not in schema
+    at addResolversToSchema (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/schema/esm/addResolversToSchema.js:80:39)
+    at stitchSchemas (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/stitch/src/stitchSchemas.ts:136:12)
+    at getStitchedSchemaFromSupergraphSdl (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/federation/src/supergraph.ts:1524:26)
+    at UnifiedGraphManager.handleFederationSupergraph (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/fusion-runtime/src/federation/supergraph.ts:188:32)
+    at UnifiedGraphManager.handleLoadedUnifiedGraph (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/fusion-runtime/src/unifiedGraphManager.ts:302:16)
+    at <anonymous> (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/fusion-runtime/src/unifiedGraphManager.ts:388:14) 
+[2025-05-26T14:56:42.614Z] ERROR  Error: Query.node defined in resolvers, but not in schema
+    at addResolversToSchema (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/schema/esm/addResolversToSchema.js:80:39)
+    at stitchSchemas (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/stitch/src/stitchSchemas.ts:136:12)
+    at getStitchedSchemaFromSupergraphSdl (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/federation/src/supergraph.ts:1524:26)
+    at UnifiedGraphManager.handleFederationSupergraph (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/fusion-runtime/src/federation/supergraph.ts:188:32)
+    at UnifiedGraphManager.handleLoadedUnifiedGraph (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/fusion-runtime/src/unifiedGraphManager.ts:302:16)
+    at <anonymous> (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/fusion-runtime/src/unifiedGraphManager.ts:388:14) 
+[2025-05-26T14:57:52.746Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
+[2025-05-26T14:57:52.753Z] INFO   Loaded config 
+[2025-05-26T14:57:52.753Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsYpodCQ/supergraph.graphql 
+[2025-05-26T14:57:52.754Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsYpodCQ/supergraph.graphql 
+[2025-05-26T14:57:52.754Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsYpodCQ/supergraph.graphql for changes 
+[2025-05-26T14:57:52.756Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsYpodCQ/supergraph.graphql 
+[2025-05-26T14:57:52.762Z] INFO   Listening on http://localhost:60826 
+[2025-05-26T14:57:53.026Z] ERROR  Error: Cannot query field "node" on type "Query".
+    at Object.node (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts:13:15)
+    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:351:24)
+    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
+    at executeOperation (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:260:18)
+    at file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:64:37
+    at Promise.then (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@whatwg-node/promise-helpers/esm/index.js:34:40)
+    at handleMaybePromise (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@whatwg-node/promise-helpers/esm/index.js:10:33)
+    at executeImpl (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:64:12)
+    at execute (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:49:12)
+    at file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/normalizedExecutor.js:13:37 {
+  path: [ 'node' ],
+  locations: [ { line: 3, column: 11 } ],
+  extensions: [Object: null prototype] {}
+} 
+[2025-05-26T15:01:11.667Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
+[2025-05-26T15:01:11.674Z] INFO   Loaded config 
+[2025-05-26T15:01:11.674Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsJCufQu/supergraph.graphql 
+[2025-05-26T15:01:11.675Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsJCufQu/supergraph.graphql 
+[2025-05-26T15:01:11.675Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsJCufQu/supergraph.graphql for changes 
+[2025-05-26T15:01:11.678Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsJCufQu/supergraph.graphql 
+[2025-05-26T15:01:11.685Z] INFO   Listening on http://localhost:61090 
+[2025-05-26T15:02:08.930Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
+[2025-05-26T15:02:08.939Z] INFO   Loaded config 
+[2025-05-26T15:02:08.939Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fs9Hcusc/supergraph.graphql 
+[2025-05-26T15:02:08.940Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fs9Hcusc/supergraph.graphql 
+[2025-05-26T15:02:08.940Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fs9Hcusc/supergraph.graphql for changes 
+[2025-05-26T15:02:08.942Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fs9Hcusc/supergraph.graphql 
+[2025-05-26T15:02:08.948Z] INFO   Listening on http://localhost:61194 
+[2025-05-26T15:02:30.927Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
+[2025-05-26T15:02:30.935Z] INFO   Loaded config 
+[2025-05-26T15:02:30.935Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfZc8xM/supergraph.graphql 
+[2025-05-26T15:02:30.936Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfZc8xM/supergraph.graphql 
+[2025-05-26T15:02:30.936Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfZc8xM/supergraph.graphql for changes 
+[2025-05-26T15:02:30.938Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfZc8xM/supergraph.graphql 
+[2025-05-26T15:02:30.944Z] INFO   Listening on http://localhost:61257 
+{ id: 'VXNlcjp1c2VyLTI=' }
+[2025-05-26T15:02:31.187Z] ERROR  Error: Cannot query field "node" on type "Query".
+    at Object.node (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts:14:15)
+    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:351:24)
+    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
+    at executeOperation (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:260:18)
+    at file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:64:37
+    at Promise.then (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@whatwg-node/promise-helpers/esm/index.js:34:40)
+    at handleMaybePromise (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@whatwg-node/promise-helpers/esm/index.js:10:33)
+    at executeImpl (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:64:12)
+    at execute (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:49:12)
+    at file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/normalizedExecutor.js:13:37 {
+  path: [ 'node' ],
+  locations: [ { line: 3, column: 11 } ],
+  extensions: [Object: null prototype] {}
+} 
+[2025-05-26T15:04:08.181Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
+[2025-05-26T15:04:08.191Z] INFO   Loaded config 
+[2025-05-26T15:04:08.191Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fstEv1aL/supergraph.graphql 
+[2025-05-26T15:04:08.191Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fstEv1aL/supergraph.graphql 
+[2025-05-26T15:04:08.191Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fstEv1aL/supergraph.graphql for changes 
+[2025-05-26T15:04:08.194Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fstEv1aL/supergraph.graphql 
+[2025-05-26T15:04:08.200Z] INFO   Listening on http://localhost:61412 
+[2025-05-26T15:04:08.458Z] ERROR  Error: Cannot return null for non-nullable field User.name.
+    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:467:19)
+    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
+    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
+    at collectAndExecuteSubfields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:736:23)
+    at completeObjectValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:726:12)
+    at completeAbstractValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:675:12)
+    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:487:16)
+    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
+    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
+    at executeOperation (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:260:18) {
+  path: [ 'node', 'name' ],
+  locations: [ { line: 5, column: 15 } ],
+  extensions: [Object: null prototype] {}
+} 
+[2025-05-26T15:05:46.728Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
+[2025-05-26T15:05:46.738Z] INFO   Loaded config 
+[2025-05-26T15:05:46.738Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fskLgGRP/supergraph.graphql 
+[2025-05-26T15:05:46.739Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fskLgGRP/supergraph.graphql 
+[2025-05-26T15:05:46.739Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fskLgGRP/supergraph.graphql for changes 
+[2025-05-26T15:05:46.741Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fskLgGRP/supergraph.graphql 
+[2025-05-26T15:05:46.747Z] INFO   Listening on http://localhost:61572 
+[2025-05-26T15:05:47.016Z] ERROR  Error: Cannot return null for non-nullable field User.name.
+    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:467:19)
+    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
+    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
+    at collectAndExecuteSubfields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:736:23)
+    at completeObjectValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:726:12)
+    at completeAbstractValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:675:12)
+    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:487:16)
+    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
+    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
+    at executeOperation (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:260:18) {
+  path: [ 'node', 'name' ],
+  locations: [ { line: 5, column: 15 } ],
+  extensions: [Object: null prototype] {}
+} 
+[2025-05-26T15:09:42.499Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
+[2025-05-26T15:09:42.508Z] INFO   Loaded config 
+[2025-05-26T15:09:42.508Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsOwxhFd/supergraph.graphql 
+[2025-05-26T15:09:42.509Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsOwxhFd/supergraph.graphql 
+[2025-05-26T15:09:42.509Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsOwxhFd/supergraph.graphql for changes 
+[2025-05-26T15:09:42.511Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsOwxhFd/supergraph.graphql 
+[2025-05-26T15:09:42.517Z] INFO   Listening on http://localhost:61887 
+[2025-05-26T15:09:42.786Z] ERROR  Error: Cannot return null for non-nullable field User.name.
+    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:467:19)
+    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
+    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
+    at collectAndExecuteSubfields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:736:23)
+    at completeObjectValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:726:12)
+    at completeAbstractValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:675:12)
+    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:487:16)
+    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
+    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
+    at executeOperation (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:260:18) {
+  path: [ 'node', 'name' ],
+  locations: [ { line: 5, column: 15 } ],
+  extensions: [Object: null prototype] {}
+} 
+[2025-05-26T15:12:09.330Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
+[2025-05-26T15:12:09.342Z] INFO   Loaded config 
+[2025-05-26T15:12:09.343Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfAkQmK/supergraph.graphql 
+[2025-05-26T15:12:09.343Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfAkQmK/supergraph.graphql 
+[2025-05-26T15:12:09.343Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfAkQmK/supergraph.graphql for changes 
+[2025-05-26T15:12:09.346Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfAkQmK/supergraph.graphql 
+[2025-05-26T15:12:09.352Z] INFO   Listening on http://localhost:62107 
+[2025-05-26T15:12:09.626Z] ERROR  Error: Cannot return null for non-nullable field User.name.
+    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:467:19)
+    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
+    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
+    at collectAndExecuteSubfields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:736:23)
+    at completeObjectValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:726:12)
+    at completeAbstractValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:675:12)
+    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:487:16)
+    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
+    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
+    at executeOperation (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:260:18) {
+  path: [ 'node', 'name' ],
+  locations: [ { line: 5, column: 15 } ],
+  extensions: [Object: null prototype] {}
+} 
diff --git a/e2e/relay-additional-resolvers/id.ts b/e2e/relay-additional-resolvers/id.ts
new file mode 100644
index 000000000..79c91eb09
--- /dev/null
+++ b/e2e/relay-additional-resolvers/id.ts
@@ -0,0 +1,20 @@
+/**
+ * Encodes a type and local ID into a global ID
+ * @param type - The type of the entity (e.g., "Person", "Story")
+ * @param localID - The local ID of the entity
+ * @returns Base64 encoded global ID
+ */
+export function encodeGlobalID(type: string, localID: string) {
+  return Buffer.from(JSON.stringify([type, localID])).toString('base64');
+}
+
+/**
+ * Decodes a global ID into its type and local ID components
+ * @param globalID - The base64 encoded global ID
+ * @returns Object containing type and local ID
+ */
+export function decodeGlobalID(globalID: string) {
+  const decoded = Buffer.from(globalID, 'base64').toString('utf-8');
+  const [type, localID] = JSON.parse(decoded) as [string, string];
+  return { type, localID };
+}
diff --git a/e2e/relay-additional-resolvers/relay-additional-resolvers.e2e.ts b/e2e/relay-additional-resolvers/relay-additional-resolvers.e2e.ts
index 70d377164..b9e90fb2e 100644
--- a/e2e/relay-additional-resolvers/relay-additional-resolvers.e2e.ts
+++ b/e2e/relay-additional-resolvers/relay-additional-resolvers.e2e.ts
@@ -1,10 +1,12 @@
 import { createTenv } from '@internal/e2e';
 import { expect, it } from 'vitest';
+import { encodeGlobalID } from './id';
 
 const { gateway, service } = createTenv(__dirname);
 
 it('should resolve the data behind the node', async () => {
   const { execute } = await gateway({
+    pipeLogs: 'gw.out',
     supergraph: {
       with: 'apollo',
       services: [await service('users'), await service('posts')],
@@ -14,8 +16,8 @@ it('should resolve the data behind the node', async () => {
   await expect(
     execute({
       query: /* GraphQL */ `
-        {
-          node(id: "user-2") {
+        query ($id: ID!) {
+          node(id: $id) {
             ... on User {
               name
               posts {
@@ -26,6 +28,26 @@ it('should resolve the data behind the node', async () => {
           }
         }
       `,
+      variables: {
+        id: encodeGlobalID('User', 'user-2'),
+      },
     }),
-  ).resolves.toMatchInlineSnapshot();
+  ).resolves.toMatchInlineSnapshot(`
+    {
+      "errors": [
+        {
+          "extensions": {
+            "code": "GRAPHQL_VALIDATION_FAILED",
+          },
+          "locations": [
+            {
+              "column": 11,
+              "line": 3,
+            },
+          ],
+          "message": "Cannot query field "node" on type "Query".",
+        },
+      ],
+    }
+  `);
 });

From 1380a588b9314c89912b9ecc502ddb92a8c32ac4 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 9 Jun 2025 16:06:47 +0200
Subject: [PATCH 03/44] start setting up tests

---
 packages/federation/src/supergraph.ts         |  5 ++
 .../getStitchedSchemaFromLocalSchemas.ts      |  3 ++
 packages/federation/tests/relay.test.ts       | 51 +++++++++++++++++++
 3 files changed, 59 insertions(+)
 create mode 100644 packages/federation/tests/relay.test.ts

diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index 55ef24126..578c3b39a 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -129,6 +129,11 @@ export interface GetStitchingOptionsFromSupergraphSdlOpts {
    * Configure the batch delegation options for all merged types in all subschemas.
    */
   batchDelegateOptions?: MergedTypeConfig['dataLoaderOptions'];
+  /**
+   * Add support for Relay's spec of Node interface aka.
+   * Global Object Identification.
+   */
+  relayObjectIdentification?: boolean;
 }
 
 export function getStitchingOptionsFromSupergraphSdl(
diff --git a/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts b/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
index ac65bc445..a0aa602db 100644
--- a/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
+++ b/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
@@ -21,6 +21,7 @@ export async function getStitchedSchemaFromLocalSchemas({
   onSubgraphExecute,
   composeWith = 'apollo',
   ignoreRules,
+  relayObjectIdentification,
 }: {
   localSchemas: Record<string, GraphQLSchema>;
   onSubgraphExecute?: (
@@ -30,6 +31,7 @@ export async function getStitchedSchemaFromLocalSchemas({
   ) => void;
   composeWith?: 'apollo' | 'guild';
   ignoreRules?: string[];
+  relayObjectIdentification?: boolean;
 }): Promise<GraphQLSchema> {
   let supergraphSdl: string;
   if (composeWith === 'apollo') {
@@ -73,6 +75,7 @@ export async function getStitchedSchemaFromLocalSchemas({
   }
   return getStitchedSchemaFromSupergraphSdl({
     supergraphSdl,
+    relayObjectIdentification,
     onSubschemaConfig(subschemaConfig) {
       const [name, localSchema] =
         Object.entries(localSchemas).find(
diff --git a/packages/federation/tests/relay.test.ts b/packages/federation/tests/relay.test.ts
new file mode 100644
index 000000000..47aa6e350
--- /dev/null
+++ b/packages/federation/tests/relay.test.ts
@@ -0,0 +1,51 @@
+import { buildSubgraphSchema } from '@apollo/subgraph';
+import { normalizedExecutor } from '@graphql-tools/executor';
+import { parse } from 'graphql';
+import { describe, expect, it } from 'vitest';
+import { getStitchedSchemaFromLocalSchemas } from './getStitchedSchemaFromLocalSchemas';
+
+describe('Relay Object Identification', () => {
+  it('should resolve node by id', async () => {
+    const accounts = buildSubgraphSchema({
+      typeDefs: parse(/* GraphQL */ `
+        type Person @key(fields: "id") {
+          id: ID!
+          name: String!
+          email: String!
+        }
+      `),
+      resolvers: {
+        Person: {
+          __resolveReference: (ref) => ({
+            id: ref.id,
+            name: 'John Doe',
+            email: 'john@doe.com',
+          }),
+        },
+      },
+    });
+
+    const supergraph = await getStitchedSchemaFromLocalSchemas({
+      localSchemas: {
+        accounts,
+      },
+    });
+
+    await expect(
+      normalizedExecutor({
+        schema: supergraph,
+        document: parse(/* GraphQL */ `
+          query ($id: ID!) {
+            node(id: $id) {
+              ... on Person {
+                id
+                name
+                email
+              }
+            }
+          }
+        `),
+      }),
+    ).resolves.toMatchInlineSnapshot();
+  });
+});

From bb9ad3ae60038058bb60785115ba3a94b177de4d Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 9 Jun 2025 16:20:11 +0200
Subject: [PATCH 04/44] lets try node froid

---
 packages/federation/package.json              |  2 +
 .../getStitchedSchemaFromLocalSchemas.ts      | 47 +++++++++++++++----
 packages/federation/tests/relay.test.ts       | 23 +++++----
 yarn.lock                                     | 23 ++++++++-
 4 files changed, 76 insertions(+), 19 deletions(-)

diff --git a/packages/federation/package.json b/packages/federation/package.json
index 617f445b1..5cc5bfc69 100644
--- a/packages/federation/package.json
+++ b/packages/federation/package.json
@@ -47,10 +47,12 @@
     "@graphql-tools/utils": "^10.8.1",
     "@graphql-tools/wrap": "workspace:^",
     "@graphql-yoga/typed-event-target": "^3.0.1",
+    "@wayfair/node-froid": "^3.2.2",
     "@whatwg-node/disposablestack": "^0.0.6",
     "@whatwg-node/events": "^0.1.2",
     "@whatwg-node/fetch": "^0.10.8",
     "@whatwg-node/promise-helpers": "^1.3.0",
+    "graphql-relay": "^0.10.2",
     "tslib": "^2.8.1"
   },
   "devDependencies": {
diff --git a/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts b/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
index a0aa602db..70fe6815e 100644
--- a/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
+++ b/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
@@ -1,13 +1,17 @@
 import { createDefaultExecutor } from '@graphql-tools/delegate';
+import { executorFromSchema } from '@graphql-tools/executor';
 import {
   ExecutionRequest,
   ExecutionResult,
   getDocumentNodeFromSchema,
 } from '@graphql-tools/utils';
-import { composeLocalSchemasWithApollo } from '@internal/testing';
+import {
+  assertSingleExecutionValue,
+  composeLocalSchemasWithApollo,
+} from '@internal/testing';
 import { composeServices } from '@theguild/federation-composition';
 import { handleMaybePromise } from '@whatwg-node/promise-helpers';
-import { GraphQLSchema } from 'graphql';
+import { GraphQLSchema, parse } from 'graphql';
 import { kebabCase } from 'lodash';
 import { getStitchedSchemaFromSupergraphSdl } from '../src/supergraph';
 
@@ -16,13 +20,7 @@ export interface LocalSchemaItem {
   schema: GraphQLSchema;
 }
 
-export async function getStitchedSchemaFromLocalSchemas({
-  localSchemas,
-  onSubgraphExecute,
-  composeWith = 'apollo',
-  ignoreRules,
-  relayObjectIdentification,
-}: {
+export interface StitchedSchemaFromLocalSchemasOptions {
   localSchemas: Record<string, GraphQLSchema>;
   onSubgraphExecute?: (
     subgraph: string,
@@ -32,7 +30,15 @@ export async function getStitchedSchemaFromLocalSchemas({
   composeWith?: 'apollo' | 'guild';
   ignoreRules?: string[];
   relayObjectIdentification?: boolean;
-}): Promise<GraphQLSchema> {
+}
+
+export async function getStitchedSchemaFromLocalSchemas({
+  localSchemas,
+  onSubgraphExecute,
+  composeWith = 'apollo',
+  ignoreRules,
+  relayObjectIdentification,
+}: StitchedSchemaFromLocalSchemasOptions): Promise<GraphQLSchema> {
   let supergraphSdl: string;
   if (composeWith === 'apollo') {
     supergraphSdl = await composeLocalSchemasWithApollo(
@@ -89,3 +95,24 @@ export async function getStitchedSchemaFromLocalSchemas({
     },
   });
 }
+
+export async function stitchLocalSchemas(
+  opts: StitchedSchemaFromLocalSchemasOptions,
+) {
+  const schema = await getStitchedSchemaFromLocalSchemas(opts);
+  const executor = executorFromSchema(schema);
+  return {
+    schema,
+    async execute({
+      query,
+      variables,
+    }: {
+      query: string;
+      variables?: Record<string, any>;
+    }) {
+      const result = await executor({ document: parse(query), variables });
+      assertSingleExecutionValue(result);
+      return result;
+    },
+  };
+}
diff --git a/packages/federation/tests/relay.test.ts b/packages/federation/tests/relay.test.ts
index 47aa6e350..c5b18ddaa 100644
--- a/packages/federation/tests/relay.test.ts
+++ b/packages/federation/tests/relay.test.ts
@@ -1,13 +1,15 @@
 import { buildSubgraphSchema } from '@apollo/subgraph';
-import { normalizedExecutor } from '@graphql-tools/executor';
 import { parse } from 'graphql';
 import { describe, expect, it } from 'vitest';
-import { getStitchedSchemaFromLocalSchemas } from './getStitchedSchemaFromLocalSchemas';
+import { stitchLocalSchemas } from './getStitchedSchemaFromLocalSchemas';
 
 describe('Relay Object Identification', () => {
   it('should resolve node by id', async () => {
     const accounts = buildSubgraphSchema({
       typeDefs: parse(/* GraphQL */ `
+        type Query {
+          people: [Person!]!
+        }
         type Person @key(fields: "id") {
           id: ID!
           name: String!
@@ -25,16 +27,16 @@ describe('Relay Object Identification', () => {
       },
     });
 
-    const supergraph = await getStitchedSchemaFromLocalSchemas({
+    const { execute } = await stitchLocalSchemas({
+      relayObjectIdentification: true,
       localSchemas: {
         accounts,
       },
     });
 
     await expect(
-      normalizedExecutor({
-        schema: supergraph,
-        document: parse(/* GraphQL */ `
+      execute({
+        query: /* GraphQL */ `
           query ($id: ID!) {
             node(id: $id) {
               ... on Person {
@@ -44,8 +46,13 @@ describe('Relay Object Identification', () => {
               }
             }
           }
-        `),
+        `,
+        variables: { id: '1' },
       }),
-    ).resolves.toMatchInlineSnapshot();
+    ).resolves.toMatchInlineSnapshot(`
+      {
+        "data": {},
+      }
+    `);
   });
 });
diff --git a/yarn.lock b/yarn.lock
index b072395f1..e6ca113fa 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -397,7 +397,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@apollo/subgraph@npm:^2.11.0":
+"@apollo/subgraph@npm:^2.10.0, @apollo/subgraph@npm:^2.11.0":
   version: 2.11.0
   resolution: "@apollo/subgraph@npm:2.11.0"
   dependencies:
@@ -5090,12 +5090,14 @@ __metadata:
     "@graphql-tools/wrap": "workspace:^"
     "@graphql-yoga/typed-event-target": "npm:^3.0.1"
     "@types/lodash": "npm:4.17.18"
+    "@wayfair/node-froid": "npm:^3.2.2"
     "@whatwg-node/disposablestack": "npm:^0.0.6"
     "@whatwg-node/events": "npm:^0.1.2"
     "@whatwg-node/fetch": "npm:^0.10.8"
     "@whatwg-node/promise-helpers": "npm:^1.3.0"
     graphql: "npm:^16.9.0"
     graphql-federation-gateway-audit: "the-guild-org/graphql-federation-gateway-audit#main"
+    graphql-relay: "npm:^0.10.2"
     pkgroll: "npm:2.13.1"
     tslib: "npm:^2.8.1"
   peerDependencies:
@@ -9264,6 +9266,16 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@wayfair/node-froid@npm:^3.2.2":
+  version: 3.2.2
+  resolution: "@wayfair/node-froid@npm:3.2.2"
+  peerDependencies:
+    graphql: ^16
+    graphql-relay: ^0.10
+  checksum: 10c0/e3cf2762757308896e2a0965b466905eacf5215c0c257df3695a815279c9186dfce56882ca95363d315a552711a426c6b35c6564be0c60e3f2eb3fe12d929543
+  languageName: node
+  linkType: hard
+
 "@whatwg-node/cookie-store@npm:^0.2.0, @whatwg-node/cookie-store@npm:^0.2.2":
   version: 0.2.3
   resolution: "@whatwg-node/cookie-store@npm:0.2.3"
@@ -14285,6 +14297,15 @@ __metadata:
   languageName: node
   linkType: hard
 
+"graphql-relay@npm:^0.10.2":
+  version: 0.10.2
+  resolution: "graphql-relay@npm:0.10.2"
+  peerDependencies:
+    graphql: ^16.2.0
+  checksum: 10c0/312748377c699c812541551cb2079308be6efef99e5398928dbbeca7596581d1fd8d939f60b2c77d184a185b64717e8c2b62b102a8f85167d379fd49cad39a3d
+  languageName: node
+  linkType: hard
+
 "graphql-scalars@npm:^1.22.4, graphql-scalars@npm:^1.23.0":
   version: 1.24.2
   resolution: "graphql-scalars@npm:1.24.2"

From 09b9ce67c5c3f81da5b84f7515ce04f9f6e8af64 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 9 Jun 2025 18:38:46 +0200
Subject: [PATCH 05/44] global object ident

---
 packages/federation/src/supergraph.ts         | 34 +++++++++++++++++--
 .../getStitchedSchemaFromLocalSchemas.ts      |  6 ++--
 ...s => global-object-identification.test.ts} |  2 +-
 3 files changed, 35 insertions(+), 7 deletions(-)
 rename packages/federation/tests/{relay.test.ts => global-object-identification.test.ts} (97%)

diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index 578c3b39a..26ee47a81 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -130,10 +130,38 @@ export interface GetStitchingOptionsFromSupergraphSdlOpts {
    */
   batchDelegateOptions?: MergedTypeConfig['dataLoaderOptions'];
   /**
-   * Add support for Relay's spec of Node interface aka.
-   * Global Object Identification.
+   * Add support for GraphQL Global Object Identification Specification  by adding a `Node`
+   * interface, `node(id: ID!): Node` and `nodes(ids: [ID!]!): [Node!]!` fields to the `Query` type.
+   *
+   * The `Node` interface will have a `nodeId` (not `id`!) field used as the global identifier. It
+   * is intentionally not `id` to avoid collisions with existing `id` fields in subgraphs.
+   *
+   * ```graphql
+   * """An object with a globally unique `ID`."""
+   * interface Node {
+   *   """
+   *   A globally unique identifier. Can be used in various places throughout the system to identify this single value.
+   *   """
+   *   nodeId: ID!
+   * }
+   *
+   * extend type Query {
+   *   """Fetches an object given its globally unique `ID`."""
+   *   node(
+   *     """The globally unique `ID`."""
+   *     nodeId: ID!
+   *   ): Node
+   *   """Fetches objects given their globally unique `ID`s."""
+   *   nodes(
+   *     """The globally unique `ID`s."""
+   *     nodeIds: [ID!]!
+   *   ): [Node!]!
+   * }
+   * ```
+   *
+   * @see https://relay.dev/graphql/objectidentification.htm
    */
-  relayObjectIdentification?: boolean;
+  globalObjectIdentification?: boolean;
 }
 
 export function getStitchingOptionsFromSupergraphSdl(
diff --git a/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts b/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
index 70fe6815e..b9cdd60e7 100644
--- a/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
+++ b/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
@@ -29,7 +29,7 @@ export interface StitchedSchemaFromLocalSchemasOptions {
   ) => void;
   composeWith?: 'apollo' | 'guild';
   ignoreRules?: string[];
-  relayObjectIdentification?: boolean;
+  globalObjectIdentification?: boolean;
 }
 
 export async function getStitchedSchemaFromLocalSchemas({
@@ -37,7 +37,7 @@ export async function getStitchedSchemaFromLocalSchemas({
   onSubgraphExecute,
   composeWith = 'apollo',
   ignoreRules,
-  relayObjectIdentification,
+  globalObjectIdentification,
 }: StitchedSchemaFromLocalSchemasOptions): Promise<GraphQLSchema> {
   let supergraphSdl: string;
   if (composeWith === 'apollo') {
@@ -81,7 +81,7 @@ export async function getStitchedSchemaFromLocalSchemas({
   }
   return getStitchedSchemaFromSupergraphSdl({
     supergraphSdl,
-    relayObjectIdentification,
+    globalObjectIdentification,
     onSubschemaConfig(subschemaConfig) {
       const [name, localSchema] =
         Object.entries(localSchemas).find(
diff --git a/packages/federation/tests/relay.test.ts b/packages/federation/tests/global-object-identification.test.ts
similarity index 97%
rename from packages/federation/tests/relay.test.ts
rename to packages/federation/tests/global-object-identification.test.ts
index c5b18ddaa..0996472a1 100644
--- a/packages/federation/tests/relay.test.ts
+++ b/packages/federation/tests/global-object-identification.test.ts
@@ -28,7 +28,7 @@ describe('Relay Object Identification', () => {
     });
 
     const { execute } = await stitchLocalSchemas({
-      relayObjectIdentification: true,
+      globalObjectIdentification: true,
       localSchemas: {
         accounts,
       },

From 696e55a9836ea747c99eb72968fdbc6dbc1dfd64 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 9 Jun 2025 20:08:53 +0200
Subject: [PATCH 06/44] revert getstitched

---
 .../getStitchedSchemaFromLocalSchemas.ts      | 49 +++++--------------
 1 file changed, 11 insertions(+), 38 deletions(-)

diff --git a/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts b/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
index b9cdd60e7..8f39045d4 100644
--- a/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
+++ b/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
@@ -1,17 +1,13 @@
 import { createDefaultExecutor } from '@graphql-tools/delegate';
-import { executorFromSchema } from '@graphql-tools/executor';
 import {
   ExecutionRequest,
   ExecutionResult,
   getDocumentNodeFromSchema,
 } from '@graphql-tools/utils';
-import {
-  assertSingleExecutionValue,
-  composeLocalSchemasWithApollo,
-} from '@internal/testing';
+import { composeLocalSchemasWithApollo } from '@internal/testing';
 import { composeServices } from '@theguild/federation-composition';
 import { handleMaybePromise } from '@whatwg-node/promise-helpers';
-import { GraphQLSchema, parse } from 'graphql';
+import { GraphQLSchema } from 'graphql';
 import { kebabCase } from 'lodash';
 import { getStitchedSchemaFromSupergraphSdl } from '../src/supergraph';
 
@@ -20,7 +16,13 @@ export interface LocalSchemaItem {
   schema: GraphQLSchema;
 }
 
-export interface StitchedSchemaFromLocalSchemasOptions {
+export async function getStitchedSchemaFromLocalSchemas({
+  localSchemas,
+  onSubgraphExecute,
+  composeWith = 'apollo',
+  ignoreRules,
+  globalObjectIdentification,
+}: {
   localSchemas: Record<string, GraphQLSchema>;
   onSubgraphExecute?: (
     subgraph: string,
@@ -30,15 +32,7 @@ export interface StitchedSchemaFromLocalSchemasOptions {
   composeWith?: 'apollo' | 'guild';
   ignoreRules?: string[];
   globalObjectIdentification?: boolean;
-}
-
-export async function getStitchedSchemaFromLocalSchemas({
-  localSchemas,
-  onSubgraphExecute,
-  composeWith = 'apollo',
-  ignoreRules,
-  globalObjectIdentification,
-}: StitchedSchemaFromLocalSchemasOptions): Promise<GraphQLSchema> {
+}): Promise<GraphQLSchema> {
   let supergraphSdl: string;
   if (composeWith === 'apollo') {
     supergraphSdl = await composeLocalSchemasWithApollo(
@@ -89,30 +83,9 @@ export async function getStitchedSchemaFromLocalSchemas({
         ) || [];
       if (name && localSchema) {
         subschemaConfig.executor = createTracedExecutor(name, localSchema);
-      } else {
+      } else if (!globalObjectIdentification) {
         throw new Error(`Unknown subgraph ${subschemaConfig.name}`);
       }
     },
   });
 }
-
-export async function stitchLocalSchemas(
-  opts: StitchedSchemaFromLocalSchemasOptions,
-) {
-  const schema = await getStitchedSchemaFromLocalSchemas(opts);
-  const executor = executorFromSchema(schema);
-  return {
-    schema,
-    async execute({
-      query,
-      variables,
-    }: {
-      query: string;
-      variables?: Record<string, any>;
-    }) {
-      const result = await executor({ document: parse(query), variables });
-      assertSingleExecutionValue(result);
-      return result;
-    },
-  };
-}

From 4ca1d97719d9009f609965d29f80474dbc7848d2 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 9 Jun 2025 20:08:58 +0200
Subject: [PATCH 07/44] begin

---
 packages/federation/src/supergraph.ts         | 43 +++++++++++++++
 .../global-object-identification.test.ts      | 54 +++++++++++--------
 2 files changed, 76 insertions(+), 21 deletions(-)

diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index 26ee47a81..0f5524ef1 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -16,6 +16,7 @@ import {
   buildHTTPExecutor,
   HTTPExecutorOptions,
 } from '@graphql-tools/executor-http';
+import { makeExecutableSchema } from '@graphql-tools/schema';
 import {
   calculateSelectionScore,
   getDefaultFieldConfigMerger,
@@ -1252,6 +1253,48 @@ export function getStitchingOptionsFromSupergraphSdl(
     subschemas.push(subschemaConfig);
   }
 
+  if (opts.globalObjectIdentification && typeNameKeysBySubgraphMap.size) {
+    const nodeIdField = 'nodeId';
+    const typeDefs = `
+      type Query {
+        """Fetches an object given its globally unique \`ID\`."""
+        node(
+          """The globally unique \`ID\`."""
+          ${nodeIdField}: ID!
+        ): Node
+      }
+      interface Node {
+        """
+        A globally unique identifier. Can be used in various places throughout the system to identify this single value.
+        """
+        ${nodeIdField}: ID!
+      }
+      ${typeNameKeysBySubgraphMap
+        .values()
+        .flatMap((type) =>
+          type.keys().map(
+            (typeName) => `
+      type ${typeName} implements Node {
+        """
+        A globally unique identifier. Can be used in various places throughout the system to identify this single value.
+        """
+        ${nodeIdField}: ID!
+      }`,
+          ),
+        )
+        .toArray()
+        .join('\n')}
+    `;
+    const globalObjectIdentSubschema: SubschemaConfig = {
+      name: 'global-object-identification',
+      schema: makeExecutableSchema({
+        typeDefs,
+        // TODO: resolvers
+      }),
+    };
+    subschemas.push(globalObjectIdentSubschema);
+  }
+
   const defaultMerger = getDefaultFieldConfigMerger(true);
   const fieldConfigMerger: TypeMergingOptions['fieldConfigMerger'] = function (
     candidates: MergeFieldConfigCandidate[],
diff --git a/packages/federation/tests/global-object-identification.test.ts b/packages/federation/tests/global-object-identification.test.ts
index 0996472a1..dd9030868 100644
--- a/packages/federation/tests/global-object-identification.test.ts
+++ b/packages/federation/tests/global-object-identification.test.ts
@@ -1,9 +1,10 @@
 import { buildSubgraphSchema } from '@apollo/subgraph';
+import { printSchemaWithDirectives } from '@graphql-tools/utils';
 import { parse } from 'graphql';
 import { describe, expect, it } from 'vitest';
-import { stitchLocalSchemas } from './getStitchedSchemaFromLocalSchemas';
+import { getStitchedSchemaFromLocalSchemas } from './getStitchedSchemaFromLocalSchemas';
 
-describe('Relay Object Identification', () => {
+describe('Global Object Identification', () => {
   it('should resolve node by id', async () => {
     const accounts = buildSubgraphSchema({
       typeDefs: parse(/* GraphQL */ `
@@ -27,32 +28,43 @@ describe('Relay Object Identification', () => {
       },
     });
 
-    const { execute } = await stitchLocalSchemas({
+    const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,
       localSchemas: {
         accounts,
       },
     });
 
-    await expect(
-      execute({
-        query: /* GraphQL */ `
-          query ($id: ID!) {
-            node(id: $id) {
-              ... on Person {
-                id
-                name
-                email
-              }
-            }
-          }
-        `,
-        variables: { id: '1' },
-      }),
-    ).resolves.toMatchInlineSnapshot(`
-      {
-        "data": {},
+    expect(printSchemaWithDirectives(schema)).toMatchInlineSnapshot(`
+      "schema {
+        query: Query
       }
+
+      type Query {
+        people: [Person!]!
+        """Fetches an object given its globally unique \`ID\`."""
+        node(
+          """The globally unique \`ID\`."""
+          nodeId: ID!
+        ): Node
+      }
+
+      type Person implements Node {
+        id: ID!
+        name: String!
+        email: String!
+        """
+        A globally unique identifier. Can be used in various places throughout the system to identify this single value.
+        """
+        nodeId: ID!
+      }
+
+      interface Node {
+        """
+        A globally unique identifier. Can be used in various places throughout the system to identify this single value.
+        """
+        nodeId: ID!
+      }"
     `);
   });
 });

From 992a6d7476cb208901ba0a1a4b88bc94f418a359 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 9 Jun 2025 20:32:56 +0200
Subject: [PATCH 08/44] schema with node

---
 packages/federation/package.json              |  1 -
 packages/federation/src/supergraph.ts         | 20 +++++++-
 .../global-object-identification.test.ts      | 50 +++++++++++--------
 yarn.lock                                     | 11 ----
 4 files changed, 48 insertions(+), 34 deletions(-)

diff --git a/packages/federation/package.json b/packages/federation/package.json
index 5cc5bfc69..9febfa147 100644
--- a/packages/federation/package.json
+++ b/packages/federation/package.json
@@ -47,7 +47,6 @@
     "@graphql-tools/utils": "^10.8.1",
     "@graphql-tools/wrap": "workspace:^",
     "@graphql-yoga/typed-event-target": "^3.0.1",
-    "@wayfair/node-froid": "^3.2.2",
     "@whatwg-node/disposablestack": "^0.0.6",
     "@whatwg-node/events": "^0.1.2",
     "@whatwg-node/fetch": "^0.10.8",
diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index 0f5524ef1..9ba2ccac5 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -68,6 +68,7 @@ import {
   visit,
   visitWithTypeInfo,
 } from 'graphql';
+import { fromGlobalId } from 'graphql-relay';
 import {
   filterInternalFieldsAndTypes,
   getArgsFromKeysForFederation,
@@ -1289,7 +1290,24 @@ export function getStitchingOptionsFromSupergraphSdl(
       name: 'global-object-identification',
       schema: makeExecutableSchema({
         typeDefs,
-        // TODO: resolvers
+        resolvers: {
+          Query: {
+            node: (_source, args: { [nodeIdField]: string }) => {
+              const id = args[nodeIdField];
+              if (!fromGlobalId(args[nodeIdField]).type) {
+                return null;
+              }
+              return {
+                [nodeIdField]: id,
+              };
+            },
+          },
+          Node: {
+            __resolveType: (source: { [nodeIdField]: string }) => {
+              return fromGlobalId(source[nodeIdField]).type;
+            },
+          },
+        },
       }),
     };
     subschemas.push(globalObjectIdentSubschema);
diff --git a/packages/federation/tests/global-object-identification.test.ts b/packages/federation/tests/global-object-identification.test.ts
index dd9030868..ada9288ad 100644
--- a/packages/federation/tests/global-object-identification.test.ts
+++ b/packages/federation/tests/global-object-identification.test.ts
@@ -1,33 +1,41 @@
 import { buildSubgraphSchema } from '@apollo/subgraph';
+import { normalizedExecutor } from '@graphql-tools/executor';
 import { printSchemaWithDirectives } from '@graphql-tools/utils';
 import { parse } from 'graphql';
+import { toGlobalId } from 'graphql-relay';
 import { describe, expect, it } from 'vitest';
 import { getStitchedSchemaFromLocalSchemas } from './getStitchedSchemaFromLocalSchemas';
 
 describe('Global Object Identification', () => {
-  it('should resolve node by id', async () => {
-    const accounts = buildSubgraphSchema({
-      typeDefs: parse(/* GraphQL */ `
-        type Query {
-          people: [Person!]!
-        }
-        type Person @key(fields: "id") {
-          id: ID!
-          name: String!
-          email: String!
-        }
-      `),
-      resolvers: {
-        Person: {
-          __resolveReference: (ref) => ({
-            id: ref.id,
-            name: 'John Doe',
-            email: 'john@doe.com',
-          }),
-        },
+  const data = {
+    accounts: [
+      {
+        id: 'a1',
+        name: 'John Doe',
+        email: 'john@doe.com',
       },
-    });
+    ],
+  };
+
+  const accounts = buildSubgraphSchema({
+    typeDefs: parse(/* GraphQL */ `
+      type Query {
+        people: [Person!]!
+      }
+      type Person @key(fields: "id") {
+        id: ID!
+        name: String!
+        email: String!
+      }
+    `),
+    resolvers: {
+      Person: {
+        __resolveReference: (ref) => data.accounts.find((a) => a.id === ref.id),
+      },
+    },
+  });
 
+  it('should generate stitched schema with node interface', async () => {
     const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,
       localSchemas: {
diff --git a/yarn.lock b/yarn.lock
index e6ca113fa..49897f373 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -5090,7 +5090,6 @@ __metadata:
     "@graphql-tools/wrap": "workspace:^"
     "@graphql-yoga/typed-event-target": "npm:^3.0.1"
     "@types/lodash": "npm:4.17.18"
-    "@wayfair/node-froid": "npm:^3.2.2"
     "@whatwg-node/disposablestack": "npm:^0.0.6"
     "@whatwg-node/events": "npm:^0.1.2"
     "@whatwg-node/fetch": "npm:^0.10.8"
@@ -9266,16 +9265,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@wayfair/node-froid@npm:^3.2.2":
-  version: 3.2.2
-  resolution: "@wayfair/node-froid@npm:3.2.2"
-  peerDependencies:
-    graphql: ^16
-    graphql-relay: ^0.10
-  checksum: 10c0/e3cf2762757308896e2a0965b466905eacf5215c0c257df3695a815279c9186dfce56882ca95363d315a552711a426c6b35c6564be0c60e3f2eb3fe12d929543
-  languageName: node
-  linkType: hard
-
 "@whatwg-node/cookie-store@npm:^0.2.0, @whatwg-node/cookie-store@npm:^0.2.2":
   version: 0.2.3
   resolution: "@whatwg-node/cookie-store@npm:0.2.3"

From 23f0c362090a0209e0cf14f4433a30ab29a9cd58 Mon Sep 17 00:00:00 2001
From: enisdenjo <badurinadenis@gmail.com>
Date: Tue, 10 Jun 2025 00:13:02 +0200
Subject: [PATCH 09/44] point to graphql org

---
 packages/federation/src/supergraph.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index 9ba2ccac5..1736a9034 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -161,7 +161,7 @@ export interface GetStitchingOptionsFromSupergraphSdlOpts {
    * }
    * ```
    *
-   * @see https://relay.dev/graphql/objectidentification.htm
+   * @see https://graphql.org/learn/global-object-identification/
    */
   globalObjectIdentification?: boolean;
 }

From 80dede930de9292649e333cb97b1cb3ee8f6ef64 Mon Sep 17 00:00:00 2001
From: enisdenjo <badurinadenis@gmail.com>
Date: Tue, 10 Jun 2025 00:26:16 +0200
Subject: [PATCH 10/44] unused

---
 packages/federation/tests/global-object-identification.test.ts | 2 --
 1 file changed, 2 deletions(-)

diff --git a/packages/federation/tests/global-object-identification.test.ts b/packages/federation/tests/global-object-identification.test.ts
index ada9288ad..e16418084 100644
--- a/packages/federation/tests/global-object-identification.test.ts
+++ b/packages/federation/tests/global-object-identification.test.ts
@@ -1,8 +1,6 @@
 import { buildSubgraphSchema } from '@apollo/subgraph';
-import { normalizedExecutor } from '@graphql-tools/executor';
 import { printSchemaWithDirectives } from '@graphql-tools/utils';
 import { parse } from 'graphql';
-import { toGlobalId } from 'graphql-relay';
 import { describe, expect, it } from 'vitest';
 import { getStitchedSchemaFromLocalSchemas } from './getStitchedSchemaFromLocalSchemas';
 

From 2e5e6635caececc67effc283808f1b4cd06314ad Mon Sep 17 00:00:00 2001
From: enisdenjo <badurinadenis@gmail.com>
Date: Tue, 10 Jun 2025 01:16:49 +0200
Subject: [PATCH 11/44] resolve basic person hardcoded

---
 packages/federation/src/supergraph.ts         | 135 +++++++++++-------
 .../global-object-identification.test.ts      |  42 ++++++
 2 files changed, 127 insertions(+), 50 deletions(-)

diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index 1736a9034..c09609a7f 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -43,7 +43,10 @@ import {
   FieldDefinitionNode,
   FieldNode,
   GraphQLFieldResolver,
+  GraphQLID,
   GraphQLInterfaceType,
+  GraphQLNonNull,
+  GraphQLObjectType,
   GraphQLOutputType,
   GraphQLSchema,
   InputValueDefinitionNode,
@@ -68,7 +71,12 @@ import {
   visit,
   visitWithTypeInfo,
 } from 'graphql';
-import { fromGlobalId } from 'graphql-relay';
+import {
+  fromGlobalId,
+  globalIdField,
+  nodeDefinitions,
+  toGlobalId,
+} from 'graphql-relay';
 import {
   filterInternalFieldsAndTypes,
   getArgsFromKeysForFederation,
@@ -1256,60 +1264,87 @@ export function getStitchingOptionsFromSupergraphSdl(
 
   if (opts.globalObjectIdentification && typeNameKeysBySubgraphMap.size) {
     const nodeIdField = 'nodeId';
-    const typeDefs = `
-      type Query {
-        """Fetches an object given its globally unique \`ID\`."""
-        node(
-          """The globally unique \`ID\`."""
-          ${nodeIdField}: ID!
-        ): Node
-      }
-      interface Node {
-        """
-        A globally unique identifier. Can be used in various places throughout the system to identify this single value.
-        """
-        ${nodeIdField}: ID!
-      }
-      ${typeNameKeysBySubgraphMap
-        .values()
-        .flatMap((type) =>
-          type.keys().map(
-            (typeName) => `
-      type ${typeName} implements Node {
-        """
-        A globally unique identifier. Can be used in various places throughout the system to identify this single value.
-        """
-        ${nodeIdField}: ID!
-      }`,
-          ),
-        )
-        .toArray()
-        .join('\n')}
-    `;
+
+    const nodeInterface = new GraphQLInterfaceType({
+      name: 'Node',
+      fields: () => ({
+        [nodeIdField]: {
+          type: new GraphQLNonNull(GraphQLID),
+          description:
+            'A globally unique identifier. Can be used in various places throughout the system to identify this single value.',
+        },
+      }),
+      resolveType: (source: { [nodeIdField]: string }) => {
+        // TODO: check when runs and with what source, do some logging
+        return fromGlobalId(source[nodeIdField]).type;
+      },
+    });
+
+    const types: GraphQLObjectType[] = [];
+    for (const [typeName, keys] of typeNameKeysBySubgraphMap
+      .values()
+      .flatMap((m) => m)) {
+      // TODO: distinct types with least keys (or respect canonical)
+      const type = new GraphQLObjectType({
+        name: typeName,
+        interfaces: [nodeInterface],
+        fields: () => ({
+          [nodeIdField]: {
+            description:
+              'A globally unique identifier. Can be used in various places throughout the system to identify this single value.',
+            type: new GraphQLNonNull(GraphQLID),
+            resolve: (source) =>
+              toGlobalId(
+                typeName,
+                // TODO: use keys
+                source.id,
+              ),
+          },
+          // TODO: use keys
+          id: {
+            type: new GraphQLNonNull(GraphQLID),
+          },
+        }),
+      });
+      types.push(type);
+    }
+
     const globalObjectIdentSubschema: SubschemaConfig = {
       name: 'global-object-identification',
-      schema: makeExecutableSchema({
-        typeDefs,
-        resolvers: {
-          Query: {
-            node: (_source, args: { [nodeIdField]: string }) => {
-              const id = args[nodeIdField];
-              if (!fromGlobalId(args[nodeIdField]).type) {
-                return null;
-              }
-              return {
-                [nodeIdField]: id,
-              };
-            },
-          },
-          Node: {
-            __resolveType: (source: { [nodeIdField]: string }) => {
-              return fromGlobalId(source[nodeIdField]).type;
+      schema: new GraphQLSchema({
+        types,
+        query: new GraphQLObjectType({
+          name: 'Query',
+          fields: () => ({
+            node: {
+              type: nodeInterface,
+              description: 'Fetches an object given its globally unique `ID`.',
+              args: {
+                [nodeIdField]: {
+                  type: new GraphQLNonNull(GraphQLID),
+                  description: 'The globally unique `ID`.',
+                },
+              },
+              resolve: (_source, args: { [nodeIdField]: string }) => {
+                const nodeId = args[nodeIdField];
+                const { id, type } = fromGlobalId(args[nodeIdField]);
+                if (!type) {
+                  return null;
+                }
+                return {
+                  __typename: type,
+                  [nodeIdField]: nodeId,
+                  // TODO: as keys
+                  id,
+                };
+              },
             },
-          },
-        },
+            // TODO: nodes
+          }),
+        }),
       }),
     };
+
     subschemas.push(globalObjectIdentSubschema);
   }
 
diff --git a/packages/federation/tests/global-object-identification.test.ts b/packages/federation/tests/global-object-identification.test.ts
index e16418084..6a3909a7e 100644
--- a/packages/federation/tests/global-object-identification.test.ts
+++ b/packages/federation/tests/global-object-identification.test.ts
@@ -1,6 +1,8 @@
 import { buildSubgraphSchema } from '@apollo/subgraph';
+import { normalizedExecutor } from '@graphql-tools/executor';
 import { printSchemaWithDirectives } from '@graphql-tools/utils';
 import { parse } from 'graphql';
+import { toGlobalId } from 'graphql-relay';
 import { describe, expect, it } from 'vitest';
 import { getStitchedSchemaFromLocalSchemas } from './getStitchedSchemaFromLocalSchemas';
 
@@ -73,4 +75,44 @@ describe('Global Object Identification', () => {
       }"
     `);
   });
+
+  it('should resolve object from globally unique node', async () => {
+    const schema = await getStitchedSchemaFromLocalSchemas({
+      globalObjectIdentification: true,
+      localSchemas: {
+        accounts,
+      },
+    });
+
+    await expect(
+      Promise.resolve(
+        normalizedExecutor({
+          schema,
+          document: parse(/* GraphQL */ `
+        {
+          node(nodeId: "${toGlobalId('Person', 'a1')}") {
+            nodeId
+            ... on Person {
+              id
+              name
+              email
+            }
+          }
+        }
+      `),
+        }),
+      ),
+    ).resolves.toMatchInlineSnapshot(`
+      {
+        "data": {
+          "node": {
+            "email": "john@doe.com",
+            "id": "a1",
+            "name": "John Doe",
+            "nodeId": "UGVyc29uOmEx",
+          },
+        },
+      }
+    `);
+  });
 });

From 1a0a0d1f78e42770baa3f3ab55866b8e9992771f Mon Sep 17 00:00:00 2001
From: enisdenjo <badurinadenis@gmail.com>
Date: Tue, 10 Jun 2025 02:07:01 +0200
Subject: [PATCH 12/44] progress progress

---
 packages/federation/src/supergraph.ts | 121 ++++++++++++++++++++------
 1 file changed, 94 insertions(+), 27 deletions(-)

diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index c09609a7f..b13d26a43 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -42,6 +42,7 @@ import {
   EnumValueDefinitionNode,
   FieldDefinitionNode,
   FieldNode,
+  GraphQLFieldConfig,
   GraphQLFieldResolver,
   GraphQLID,
   GraphQLInterfaceType,
@@ -1280,39 +1281,105 @@ export function getStitchingOptionsFromSupergraphSdl(
       },
     });
 
-    const types: GraphQLObjectType[] = [];
-    for (const [typeName, keys] of typeNameKeysBySubgraphMap
-      .values()
-      .flatMap((m) => m)) {
-      // TODO: distinct types with least keys (or respect canonical)
-      const type = new GraphQLObjectType({
-        name: typeName,
-        interfaces: [nodeInterface],
-        fields: () => ({
-          [nodeIdField]: {
-            description:
-              'A globally unique identifier. Can be used in various places throughout the system to identify this single value.',
-            type: new GraphQLNonNull(GraphQLID),
-            resolve: (source) =>
-              toGlobalId(
-                typeName,
-                // TODO: use keys
-                source.id,
+    const types = new Map<string, GraphQLObjectType>();
+    for (const [subgraphName, typeNameKeys] of typeNameKeysBySubgraphMap) {
+      typeNames: for (const [typeName, keys] of typeNameKeys) {
+        for (const key of keys.sort(
+          (a, b) =>
+            // sort by shorter keys first
+            // TODO: respect canonical keys
+            a.length - b.length,
+        )) {
+          if (types.has(typeName)) {
+            // type already constructed to be resolved by global object identification
+            // with the best key, skip it in all other occurrences
+            continue typeNames;
+          }
+
+          if (
+            // the key for fetching this object contains other objects,
+            key.includes('{') ||
+            // the key for fetching this object contains arguments,
+            key.includes('(')
+          ) {
+            // it's too complex to use global object identification
+            // TODO: do it anyways when need arises
+            continue;
+          }
+          if (key.includes(':')) {
+            throw new Error(
+              'Aliases in @key fields are not supported by Global Object Identification yet.',
+            );
+          }
+
+          // what we're left in the "key" are simple field(s) like "id" or "email"
+          const fieldNames = key.trim().split(/\s+/);
+          if (fieldNames.includes(nodeIdField)) {
+            throw new Error(
+              `The field "${nodeIdField}" is reserved for Global Object Identification and cannot be used in @key fields for type "${typeName}".`,
+            );
+          }
+
+          const schema = subschemas.find(
+            (s) => s.name === subgraphName,
+          )?.schema;
+          if (!schema) {
+            throw new Error(
+              `Subgraph "${subgraphName}" not found for Global Object Identification.`,
+            );
+          }
+
+          const objectInSubgraph = schema.getType(
+            typeName,
+          ) as GraphQLObjectType;
+          const fieldsOfObjectInSubgraph = objectInSubgraph.getFields();
+
+          // TODO: distinct types with least keys (or respect canonical)
+          const object = new GraphQLObjectType({
+            name: typeName,
+            interfaces: [nodeInterface],
+            fields: () => ({
+              [nodeIdField]: {
+                description:
+                  'A globally unique identifier. Can be used in various places throughout the system to identify this single value.',
+                type: new GraphQLNonNull(GraphQLID),
+                resolve: (source) =>
+                  toGlobalId(
+                    typeName,
+                    // TODO: use keys
+                    source.id,
+                  ),
+              },
+              ...fieldNames.reduce(
+                (acc, fieldName) => {
+                  const fieldInSubgraph = fieldsOfObjectInSubgraph[fieldName];
+                  if (!fieldInSubgraph) {
+                    throw new Error(
+                      `Field "${fieldName}" not found in type "${typeName}" in subgraph "${subgraphName}".`,
+                    );
+                  }
+                  return {
+                    ...acc,
+                    [fieldName]: {
+                      // TODO: other config? necessary?
+                      type: fieldInSubgraph.type,
+                    },
+                  };
+                },
+                {} as Record<string, GraphQLFieldConfig<unknown, unknown>>,
               ),
-          },
-          // TODO: use keys
-          id: {
-            type: new GraphQLNonNull(GraphQLID),
-          },
-        }),
-      });
-      types.push(type);
+            }),
+          });
+
+          types.set(typeName, object);
+        }
+      }
     }
 
     const globalObjectIdentSubschema: SubschemaConfig = {
       name: 'global-object-identification',
       schema: new GraphQLSchema({
-        types,
+        types: types.values().toArray(),
         query: new GraphQLObjectType({
           name: 'Query',
           fields: () => ({

From f8c54002c61c9d4a077ac99786c1a74e357bc8cd Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Tue, 10 Jun 2025 11:22:29 +0200
Subject: [PATCH 13/44] handle multiple fields keys

---
 packages/federation/src/supergraph.ts | 94 ++++++++++++++++++---------
 1 file changed, 62 insertions(+), 32 deletions(-)

diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index b13d26a43..52327a20c 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -16,7 +16,6 @@ import {
   buildHTTPExecutor,
   HTTPExecutorOptions,
 } from '@graphql-tools/executor-http';
-import { makeExecutableSchema } from '@graphql-tools/schema';
 import {
   calculateSelectionScore,
   getDefaultFieldConfigMerger,
@@ -72,12 +71,7 @@ import {
   visit,
   visitWithTypeInfo,
 } from 'graphql';
-import {
-  fromGlobalId,
-  globalIdField,
-  nodeDefinitions,
-  toGlobalId,
-} from 'graphql-relay';
+import { fromGlobalId, toGlobalId } from 'graphql-relay';
 import {
   filterInternalFieldsAndTypes,
   getArgsFromKeysForFederation,
@@ -1281,7 +1275,10 @@ export function getStitchingOptionsFromSupergraphSdl(
       },
     });
 
-    const types = new Map<string, GraphQLObjectType>();
+    const types = new Map<
+      string,
+      { object: GraphQLObjectType; keyFieldNames: string[] }
+    >();
     for (const [subgraphName, typeNameKeys] of typeNameKeysBySubgraphMap) {
       typeNames: for (const [typeName, keys] of typeNameKeys) {
         for (const key of keys.sort(
@@ -1297,9 +1294,9 @@ export function getStitchingOptionsFromSupergraphSdl(
           }
 
           if (
-            // the key for fetching this object contains other objects,
+            // the key for fetching this object contains other objects
             key.includes('{') ||
-            // the key for fetching this object contains arguments,
+            // the key for fetching this object contains arguments
             key.includes('(')
           ) {
             // it's too complex to use global object identification
@@ -1313,8 +1310,8 @@ export function getStitchingOptionsFromSupergraphSdl(
           }
 
           // what we're left in the "key" are simple field(s) like "id" or "email"
-          const fieldNames = key.trim().split(/\s+/);
-          if (fieldNames.includes(nodeIdField)) {
+          const keyFieldNames = key.trim().split(/\s+/);
+          if (keyFieldNames.includes(nodeIdField)) {
             throw new Error(
               `The field "${nodeIdField}" is reserved for Global Object Identification and cannot be used in @key fields for type "${typeName}".`,
             );
@@ -1334,7 +1331,6 @@ export function getStitchingOptionsFromSupergraphSdl(
           ) as GraphQLObjectType;
           const fieldsOfObjectInSubgraph = objectInSubgraph.getFields();
 
-          // TODO: distinct types with least keys (or respect canonical)
           const object = new GraphQLObjectType({
             name: typeName,
             interfaces: [nodeInterface],
@@ -1343,14 +1339,21 @@ export function getStitchingOptionsFromSupergraphSdl(
                 description:
                   'A globally unique identifier. Can be used in various places throughout the system to identify this single value.',
                 type: new GraphQLNonNull(GraphQLID),
-                resolve: (source) =>
-                  toGlobalId(
-                    typeName,
-                    // TODO: use keys
-                    source.id,
-                  ),
+                resolve: (source) => {
+                  if (keyFieldNames.length === 1) {
+                    // single field key
+                    return toGlobalId(typeName, source[keyFieldNames[0]!]);
+                  }
+                  // multiple fields key
+                  const fields: Record<string, unknown> = {};
+                  for (const fieldName of keyFieldNames) {
+                    // loop is faster than reduce
+                    fields[fieldName] = source[fieldName];
+                  }
+                  return toGlobalId(typeName, JSON.stringify(fields));
+                },
               },
-              ...fieldNames.reduce(
+              ...keyFieldNames.reduce(
                 (acc, fieldName) => {
                   const fieldInSubgraph = fieldsOfObjectInSubgraph[fieldName];
                   if (!fieldInSubgraph) {
@@ -1361,7 +1364,7 @@ export function getStitchingOptionsFromSupergraphSdl(
                   return {
                     ...acc,
                     [fieldName]: {
-                      // TODO: other config? necessary?
+                      // TODO: copy other field config from subgraph type? necessary?
                       type: fieldInSubgraph.type,
                     },
                   };
@@ -1371,7 +1374,7 @@ export function getStitchingOptionsFromSupergraphSdl(
             }),
           });
 
-          types.set(typeName, object);
+          types.set(typeName, { object, keyFieldNames });
         }
       }
     }
@@ -1379,10 +1382,14 @@ export function getStitchingOptionsFromSupergraphSdl(
     const globalObjectIdentSubschema: SubschemaConfig = {
       name: 'global-object-identification',
       schema: new GraphQLSchema({
-        types: types.values().toArray(),
+        types: types
+          .values()
+          .map(({ object }) => object)
+          .toArray(),
         query: new GraphQLObjectType({
           name: 'Query',
           fields: () => ({
+            // TODO: nodes(ids: [ID!]!): [Node!]!
             node: {
               type: nodeInterface,
               description: 'Fetches an object given its globally unique `ID`.',
@@ -1394,19 +1401,42 @@ export function getStitchingOptionsFromSupergraphSdl(
               },
               resolve: (_source, args: { [nodeIdField]: string }) => {
                 const nodeId = args[nodeIdField];
-                const { id, type } = fromGlobalId(args[nodeIdField]);
-                if (!type) {
+                const { id: idOrFields, type } = fromGlobalId(
+                  args[nodeIdField],
+                );
+                if (!idOrFields || !type) {
+                  return null;
+                }
+                const { keyFieldNames } = types.get(type) || {};
+                if (!keyFieldNames) {
+                  return null;
+                }
+                if (keyFieldNames.length === 1) {
+                  // single field key
+                  return {
+                    __typename: type,
+                    [nodeIdField]: nodeId,
+                    [keyFieldNames[0]!]: idOrFields,
+                  };
+                }
+                // multiple fields key
+                try {
+                  const fields: Record<string, unknown> = {};
+                  const idFields = JSON.parse(idOrFields);
+                  for (const fieldName of keyFieldNames) {
+                    // loop is faster than reduce
+                    fields[fieldName] = idFields[fieldName];
+                  }
+                  return {
+                    __typename: type,
+                    [nodeIdField]: nodeId,
+                    ...fields,
+                  };
+                } catch {
                   return null;
                 }
-                return {
-                  __typename: type,
-                  [nodeIdField]: nodeId,
-                  // TODO: as keys
-                  id,
-                };
               },
             },
-            // TODO: nodes
           }),
         }),
       }),

From 9904c238cf6e34a5daf57f2b84c3c84861b99766 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Tue, 10 Jun 2025 11:25:58 +0200
Subject: [PATCH 14/44] people

---
 .../tests/global-object-identification.test.ts           | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/packages/federation/tests/global-object-identification.test.ts b/packages/federation/tests/global-object-identification.test.ts
index 6a3909a7e..a3c615a59 100644
--- a/packages/federation/tests/global-object-identification.test.ts
+++ b/packages/federation/tests/global-object-identification.test.ts
@@ -17,7 +17,7 @@ describe('Global Object Identification', () => {
     ],
   };
 
-  const accounts = buildSubgraphSchema({
+  const people = buildSubgraphSchema({
     typeDefs: parse(/* GraphQL */ `
       type Query {
         people: [Person!]!
@@ -29,6 +29,9 @@ describe('Global Object Identification', () => {
       }
     `),
     resolvers: {
+      Query: {
+        people: () => data.accounts,
+      },
       Person: {
         __resolveReference: (ref) => data.accounts.find((a) => a.id === ref.id),
       },
@@ -39,7 +42,7 @@ describe('Global Object Identification', () => {
     const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,
       localSchemas: {
-        accounts,
+        people,
       },
     });
 
@@ -80,7 +83,7 @@ describe('Global Object Identification', () => {
     const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,
       localSchemas: {
-        accounts,
+        people,
       },
     });
 

From a092309ba0370a4488a7bb44c7ba923d8222cae7 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Tue, 10 Jun 2025 11:32:43 +0200
Subject: [PATCH 15/44] test for nodeid

---
 .../global-object-identification.test.ts      | 40 +++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/packages/federation/tests/global-object-identification.test.ts b/packages/federation/tests/global-object-identification.test.ts
index a3c615a59..22daee834 100644
--- a/packages/federation/tests/global-object-identification.test.ts
+++ b/packages/federation/tests/global-object-identification.test.ts
@@ -118,4 +118,44 @@ describe('Global Object Identification', () => {
       }
     `);
   });
+
+  it('should resolve node id from object', async () => {
+    const schema = await getStitchedSchemaFromLocalSchemas({
+      globalObjectIdentification: true,
+      localSchemas: {
+        people,
+      },
+    });
+
+    await expect(
+      Promise.resolve(
+        normalizedExecutor({
+          schema,
+          document: parse(/* GraphQL */ `
+            {
+              people {
+                nodeId
+                id
+                name
+                email
+              }
+            }
+          `),
+        }),
+      ),
+    ).resolves.toMatchInlineSnapshot(`
+      {
+        "data": {
+          "people": [
+            {
+              "email": "john@doe.com",
+              "id": "a1",
+              "name": "John Doe",
+              "nodeId": "UGVyc29uOmEx",
+            },
+          ],
+        },
+      }
+    `);
+  });
 });

From a3e6c2345d287ee378c9e6906cbb813b529f0291 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Tue, 10 Jun 2025 12:26:39 +0200
Subject: [PATCH 16/44] resolve nodeId

---
 packages/federation/src/supergraph.ts | 67 +++++++++++++++++++--------
 1 file changed, 47 insertions(+), 20 deletions(-)

diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index 52327a20c..ae41bc884 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -1269,15 +1269,17 @@ export function getStitchingOptionsFromSupergraphSdl(
             'A globally unique identifier. Can be used in various places throughout the system to identify this single value.',
         },
       }),
-      resolveType: (source: { [nodeIdField]: string }) => {
-        // TODO: check when runs and with what source, do some logging
-        return fromGlobalId(source[nodeIdField]).type;
-      },
+      // NOTE: resolve type from the nodeId is not necessary because Query.node will do that
+      resolveType: ({ __typename }: { __typename: string }) => __typename,
     });
 
     const types = new Map<
       string,
-      { object: GraphQLObjectType; keyFieldNames: string[] }
+      {
+        object: GraphQLObjectType;
+        keySelectionSet: string;
+        keyFieldNames: string[];
+      }
     >();
     for (const [subgraphName, typeNameKeys] of typeNameKeysBySubgraphMap) {
       typeNames: for (const [typeName, keys] of typeNameKeys) {
@@ -1339,19 +1341,7 @@ export function getStitchingOptionsFromSupergraphSdl(
                 description:
                   'A globally unique identifier. Can be used in various places throughout the system to identify this single value.',
                 type: new GraphQLNonNull(GraphQLID),
-                resolve: (source) => {
-                  if (keyFieldNames.length === 1) {
-                    // single field key
-                    return toGlobalId(typeName, source[keyFieldNames[0]!]);
-                  }
-                  // multiple fields key
-                  const fields: Record<string, unknown> = {};
-                  for (const fieldName of keyFieldNames) {
-                    // loop is faster than reduce
-                    fields[fieldName] = source[fieldName];
-                  }
-                  return toGlobalId(typeName, JSON.stringify(fields));
-                },
+                // NOTE: resolve function is not necessary here because Query.node will provide all fields
               },
               ...keyFieldNames.reduce(
                 (acc, fieldName) => {
@@ -1364,8 +1354,8 @@ export function getStitchingOptionsFromSupergraphSdl(
                   return {
                     ...acc,
                     [fieldName]: {
-                      // TODO: copy other field config from subgraph type? necessary?
                       type: fieldInSubgraph.type,
+                      // NOTE: resolve function is not necessary for the rest of fields because this subgraph will never resolve them
                     },
                   };
                 },
@@ -1374,13 +1364,50 @@ export function getStitchingOptionsFromSupergraphSdl(
             }),
           });
 
-          types.set(typeName, { object, keyFieldNames });
+          types.set(typeName, {
+            object,
+            keySelectionSet: `{ ${key} }`,
+            keyFieldNames,
+          });
         }
       }
     }
 
     const globalObjectIdentSubschema: SubschemaConfig = {
+      // TODO: make sure there is no conflict with other subschemas
       name: 'global-object-identification',
+      merge: {
+        ...types.entries().reduce(
+          (acc, [typeName, { keySelectionSet, keyFieldNames }]) => ({
+            ...acc,
+            [typeName]: {
+              fieldName: 'node',
+              selectionSet: keySelectionSet,
+              args: (source) => {
+                if (keyFieldNames.length === 1) {
+                  // single field key
+                  return {
+                    [nodeIdField]: toGlobalId(
+                      typeName,
+                      source[keyFieldNames[0]!],
+                    ),
+                  };
+                }
+                // multiple fields key
+                const fields: Record<string, unknown> = {};
+                for (const fieldName of keyFieldNames) {
+                  // loop is faster than reduce
+                  fields[fieldName] = source[fieldName];
+                }
+                return {
+                  [nodeIdField]: toGlobalId(typeName, JSON.stringify(fields)),
+                };
+              },
+            },
+          }),
+          {} as Record<string, MergedTypeConfig>,
+        ),
+      },
       schema: new GraphQLSchema({
         types: types
           .values()

From c52d431aa3727d0d038cd86c258ef4d05bf4b77c Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Tue, 10 Jun 2025 12:27:52 +0200
Subject: [PATCH 17/44] accounts

---
 .../global-object-identification.test.ts      | 32 +++++++++----------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/packages/federation/tests/global-object-identification.test.ts b/packages/federation/tests/global-object-identification.test.ts
index 22daee834..b8fcd90c5 100644
--- a/packages/federation/tests/global-object-identification.test.ts
+++ b/packages/federation/tests/global-object-identification.test.ts
@@ -17,12 +17,12 @@ describe('Global Object Identification', () => {
     ],
   };
 
-  const people = buildSubgraphSchema({
+  const accounts = buildSubgraphSchema({
     typeDefs: parse(/* GraphQL */ `
       type Query {
-        people: [Person!]!
+        accounts: [Account!]!
       }
-      type Person @key(fields: "id") {
+      type Account @key(fields: "id") {
         id: ID!
         name: String!
         email: String!
@@ -30,9 +30,9 @@ describe('Global Object Identification', () => {
     `),
     resolvers: {
       Query: {
-        people: () => data.accounts,
+        accounts: () => data.accounts,
       },
-      Person: {
+      Account: {
         __resolveReference: (ref) => data.accounts.find((a) => a.id === ref.id),
       },
     },
@@ -42,7 +42,7 @@ describe('Global Object Identification', () => {
     const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,
       localSchemas: {
-        people,
+        accounts,
       },
     });
 
@@ -52,7 +52,7 @@ describe('Global Object Identification', () => {
       }
 
       type Query {
-        people: [Person!]!
+        accounts: [Account!]!
         """Fetches an object given its globally unique \`ID\`."""
         node(
           """The globally unique \`ID\`."""
@@ -60,7 +60,7 @@ describe('Global Object Identification', () => {
         ): Node
       }
 
-      type Person implements Node {
+      type Account implements Node {
         id: ID!
         name: String!
         email: String!
@@ -83,7 +83,7 @@ describe('Global Object Identification', () => {
     const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,
       localSchemas: {
-        people,
+        accounts,
       },
     });
 
@@ -93,9 +93,9 @@ describe('Global Object Identification', () => {
           schema,
           document: parse(/* GraphQL */ `
         {
-          node(nodeId: "${toGlobalId('Person', 'a1')}") {
+          node(nodeId: "${toGlobalId('Account', 'a1')}") {
             nodeId
-            ... on Person {
+            ... on Account {
               id
               name
               email
@@ -112,7 +112,7 @@ describe('Global Object Identification', () => {
             "email": "john@doe.com",
             "id": "a1",
             "name": "John Doe",
-            "nodeId": "UGVyc29uOmEx",
+            "nodeId": "QWNjb3VudDphMQ==",
           },
         },
       }
@@ -123,7 +123,7 @@ describe('Global Object Identification', () => {
     const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,
       localSchemas: {
-        people,
+        accounts,
       },
     });
 
@@ -133,7 +133,7 @@ describe('Global Object Identification', () => {
           schema,
           document: parse(/* GraphQL */ `
             {
-              people {
+              accounts {
                 nodeId
                 id
                 name
@@ -146,12 +146,12 @@ describe('Global Object Identification', () => {
     ).resolves.toMatchInlineSnapshot(`
       {
         "data": {
-          "people": [
+          "accounts": [
             {
               "email": "john@doe.com",
               "id": "a1",
               "name": "John Doe",
-              "nodeId": "UGVyc29uOmEx",
+              "nodeId": "QWNjb3VudDphMQ==",
             },
           ],
         },

From a0745305d68e33e919e1b29ec8b5fd611efa015c Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Tue, 10 Jun 2025 12:32:44 +0200
Subject: [PATCH 18/44] multiple fields key

---
 .../global-object-identification.test.ts      | 76 ++++++++++++++++++-
 1 file changed, 75 insertions(+), 1 deletion(-)

diff --git a/packages/federation/tests/global-object-identification.test.ts b/packages/federation/tests/global-object-identification.test.ts
index b8fcd90c5..5d8240e31 100644
--- a/packages/federation/tests/global-object-identification.test.ts
+++ b/packages/federation/tests/global-object-identification.test.ts
@@ -15,6 +15,18 @@ describe('Global Object Identification', () => {
         email: 'john@doe.com',
       },
     ],
+    people: [
+      {
+        firstName: 'John',
+        lastName: 'Doe',
+        email: 'john@doe.com',
+      },
+      {
+        firstName: 'Jane',
+        lastName: 'Doe',
+        email: 'jane@doe.com',
+      },
+    ],
   };
 
   const accounts = buildSubgraphSchema({
@@ -38,6 +50,30 @@ describe('Global Object Identification', () => {
     },
   });
 
+  const people = buildSubgraphSchema({
+    typeDefs: parse(/* GraphQL */ `
+      type Query {
+        people: [Person!]!
+      }
+      type Person @key(fields: "firstName lastName") {
+        firstName: String!
+        lastName: String!
+        email: String!
+      }
+    `),
+    resolvers: {
+      Query: {
+        people: () => data.people,
+      },
+      Person: {
+        __resolveReference: (ref) =>
+          data.people.find(
+            (a) => a.firstName === ref.firstName && a.lastName === ref.lastName,
+          ),
+      },
+    },
+  });
+
   it('should generate stitched schema with node interface', async () => {
     const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,
@@ -79,7 +115,7 @@ describe('Global Object Identification', () => {
     `);
   });
 
-  it('should resolve object from globally unique node', async () => {
+  it('should resolve single field key object from globally unique node', async () => {
     const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,
       localSchemas: {
@@ -119,6 +155,44 @@ describe('Global Object Identification', () => {
     `);
   });
 
+  it('should resolve multiple fields key object from globally unique node', async () => {
+    const schema = await getStitchedSchemaFromLocalSchemas({
+      globalObjectIdentification: true,
+      localSchemas: {
+        people,
+      },
+    });
+
+    await expect(
+      Promise.resolve(
+        normalizedExecutor({
+          schema,
+          document: parse(/* GraphQL */ `
+        {
+          node(nodeId: "${toGlobalId('Person', JSON.stringify({ firstName: 'John', lastName: 'Doe' }))}") {
+            nodeId
+            ... on Person {
+              firstName
+              lastName
+            }
+          }
+        }
+      `),
+        }),
+      ),
+    ).resolves.toMatchInlineSnapshot(`
+      {
+        "data": {
+          "node": {
+            "firstName": "John",
+            "lastName": "Doe",
+            "nodeId": "UGVyc29uOnsiZmlyc3ROYW1lIjoiSm9obiIsImxhc3ROYW1lIjoiRG9lIn0=",
+          },
+        },
+      }
+    `);
+  });
+
   it('should resolve node id from object', async () => {
     const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,

From 07fcd8a94c2e1f550ac7f92fcf633a29c318e5f4 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Tue, 10 Jun 2025 21:35:19 +0200
Subject: [PATCH 19/44] use additional resolvers, better

---
 .../src/globalObjectIdentification.ts         | 213 ++++++++++++++
 packages/federation/src/supergraph.ts         | 260 +++---------------
 ....ts => globalObjectIdentification.test.ts} |  35 +++
 3 files changed, 282 insertions(+), 226 deletions(-)
 create mode 100644 packages/federation/src/globalObjectIdentification.ts
 rename packages/federation/tests/{global-object-identification.test.ts => globalObjectIdentification.test.ts} (87%)

diff --git a/packages/federation/src/globalObjectIdentification.ts b/packages/federation/src/globalObjectIdentification.ts
new file mode 100644
index 000000000..870bc2032
--- /dev/null
+++ b/packages/federation/src/globalObjectIdentification.ts
@@ -0,0 +1,213 @@
+import { batchDelegateToSchema } from '@graphql-tools/batch-delegate';
+import { SubschemaConfig } from '@graphql-tools/delegate';
+import { IResolvers } from '@graphql-tools/utils';
+import {
+  DefinitionNode,
+  FieldDefinitionNode,
+  InterfaceTypeDefinitionNode,
+  Kind,
+  ObjectTypeExtensionNode,
+} from 'graphql';
+import { fromGlobalId, toGlobalId } from 'graphql-relay';
+import { MergedTypeConfigFromEntities } from './supergraph';
+
+export interface GlobalObjectIdentificationOptions {
+  nodeIdField: string;
+  subschemas: SubschemaConfig[];
+}
+
+export function createNodeDefinitions({
+  nodeIdField,
+  subschemas,
+}: GlobalObjectIdentificationOptions) {
+  const defs: DefinitionNode[] = [];
+
+  // nodeId: ID
+
+  const nodeIdFieldDef: FieldDefinitionNode = {
+    kind: Kind.FIELD_DEFINITION,
+    name: {
+      kind: Kind.NAME,
+      value: nodeIdField,
+    },
+    description: {
+      kind: Kind.STRING,
+      value:
+        'A globally unique identifier. Can be used in various places throughout the system to identify this single value.',
+    },
+    type: {
+      kind: Kind.NON_NULL_TYPE,
+      type: {
+        kind: Kind.NAMED_TYPE,
+        name: {
+          kind: Kind.NAME,
+          value: 'ID',
+        },
+      },
+    },
+  };
+
+  // interface Node
+
+  const nodeInterfaceDef: InterfaceTypeDefinitionNode = {
+    kind: Kind.INTERFACE_TYPE_DEFINITION,
+    name: {
+      kind: Kind.NAME,
+      value: 'Node',
+    },
+    fields: [nodeIdFieldDef],
+  };
+
+  defs.push(nodeInterfaceDef);
+
+  // extend type X implements Node
+
+  for (const { typeName } of getResolveableTypes(subschemas)) {
+    const typeExtensionDef: ObjectTypeExtensionNode = {
+      kind: Kind.OBJECT_TYPE_EXTENSION,
+      name: {
+        kind: Kind.NAME,
+        value: typeName,
+      },
+      interfaces: [
+        {
+          kind: Kind.NAMED_TYPE,
+          name: {
+            kind: Kind.NAME,
+            value: 'Node',
+          },
+        },
+      ],
+      fields: [nodeIdFieldDef],
+    };
+    defs.push(typeExtensionDef);
+  }
+
+  // extend type Query { nodeId: ID! }
+
+  const queryExtensionDef: ObjectTypeExtensionNode = {
+    kind: Kind.OBJECT_TYPE_EXTENSION,
+    name: {
+      kind: Kind.NAME,
+      value: 'Query',
+    },
+    fields: [
+      {
+        kind: Kind.FIELD_DEFINITION,
+        name: {
+          kind: Kind.NAME,
+          value: 'node',
+        },
+        description: {
+          kind: Kind.STRING,
+          value: 'Fetches an object given its globally unique `ID`.',
+        },
+        type: {
+          kind: Kind.NAMED_TYPE,
+          name: {
+            kind: Kind.NAME,
+            value: 'Node',
+          },
+        },
+        arguments: [
+          {
+            kind: Kind.INPUT_VALUE_DEFINITION,
+            name: {
+              kind: Kind.NAME,
+              value: nodeIdField,
+            },
+            description: {
+              kind: Kind.STRING,
+              value: 'The globally unique `ID`.',
+            },
+            type: {
+              kind: Kind.NON_NULL_TYPE,
+              type: {
+                kind: Kind.NAMED_TYPE,
+                name: {
+                  kind: Kind.NAME,
+                  value: 'ID',
+                },
+              },
+            },
+          },
+        ],
+      },
+    ],
+  };
+
+  defs.push(queryExtensionDef);
+
+  return defs;
+}
+
+export function createResolvers({
+  nodeIdField,
+  subschemas,
+}: GlobalObjectIdentificationOptions): IResolvers {
+  const types = getResolveableTypesMap(subschemas);
+  return {
+    Query: {
+      node(_source, { nodeId }, context, info) {
+        const { id, type: typeName } = fromGlobalId(nodeId);
+        const { subschema, merge } = types[typeName] || {};
+        if (!subschema || !merge) {
+          return null;
+        }
+        const { key, selectionSet, ...batchOpts } = merge;
+        return batchDelegateToSchema({
+          ...batchOpts,
+          schema: subschema,
+          key: { __typename: typeName, id }, // TODO: use keys
+          info,
+          context,
+          valuesFromResults: (results) =>
+            // add the nodeId field to the results
+            results.map((r: any) =>
+              !r ? null : { ...r, [nodeIdField]: nodeId },
+            ),
+        });
+      },
+    },
+    Account: {
+      [nodeIdField](source) {
+        return toGlobalId('Account', source.id); // TODO: use keys
+      },
+    },
+  };
+}
+
+function* getResolveableTypes(subschemas: Iterable<SubschemaConfig>) {
+  for (const subschema of subschemas) {
+    for (const [typeName, merge] of Object.entries(subschema.merge || {})) {
+      if (
+        !merge.selectionSet ||
+        !merge.argsFromKeys ||
+        !merge.key ||
+        !merge.fieldName ||
+        !merge.dataLoaderOptions
+      ) {
+        continue;
+      }
+      // TODO: provide the best and shortest path type
+      yield {
+        typeName,
+        subschema,
+        merge: merge as MergedTypeConfigFromEntities,
+      };
+    }
+  }
+}
+
+function getResolveableTypesMap(subschemas: Iterable<SubschemaConfig>) {
+  const types: Record<
+    string,
+    { subschema: SubschemaConfig; merge: MergedTypeConfigFromEntities }
+  > = {};
+  for (const { typeName, merge, subschema } of getResolveableTypes(
+    subschemas,
+  )) {
+    types[typeName] = { subschema, merge };
+  }
+  return types;
+}
diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index ae41bc884..faa16cd97 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -41,12 +41,8 @@ import {
   EnumValueDefinitionNode,
   FieldDefinitionNode,
   FieldNode,
-  GraphQLFieldConfig,
   GraphQLFieldResolver,
-  GraphQLID,
   GraphQLInterfaceType,
-  GraphQLNonNull,
-  GraphQLObjectType,
   GraphQLOutputType,
   GraphQLSchema,
   InputValueDefinitionNode,
@@ -71,7 +67,10 @@ import {
   visit,
   visitWithTypeInfo,
 } from 'graphql';
-import { fromGlobalId, toGlobalId } from 'graphql-relay';
+import {
+  createNodeDefinitions,
+  createResolvers,
+} from './globalObjectIdentification.js';
 import {
   filterInternalFieldsAndTypes,
   getArgsFromKeysForFederation,
@@ -872,7 +871,9 @@ export function getStitchingOptionsFromSupergraphSdl(
           mergedTypeConfig.canonical = true;
         }
 
-        function getMergedTypeConfigFromKey(key: string) {
+        function getMergedTypeConfigFromKey(
+          key: string,
+        ): MergedTypeConfigFromEntities {
           return {
             selectionSet: `{ ${key} }`,
             argsFromKeys: getArgsFromKeysForFederation,
@@ -1257,221 +1258,6 @@ export function getStitchingOptionsFromSupergraphSdl(
     subschemas.push(subschemaConfig);
   }
 
-  if (opts.globalObjectIdentification && typeNameKeysBySubgraphMap.size) {
-    const nodeIdField = 'nodeId';
-
-    const nodeInterface = new GraphQLInterfaceType({
-      name: 'Node',
-      fields: () => ({
-        [nodeIdField]: {
-          type: new GraphQLNonNull(GraphQLID),
-          description:
-            'A globally unique identifier. Can be used in various places throughout the system to identify this single value.',
-        },
-      }),
-      // NOTE: resolve type from the nodeId is not necessary because Query.node will do that
-      resolveType: ({ __typename }: { __typename: string }) => __typename,
-    });
-
-    const types = new Map<
-      string,
-      {
-        object: GraphQLObjectType;
-        keySelectionSet: string;
-        keyFieldNames: string[];
-      }
-    >();
-    for (const [subgraphName, typeNameKeys] of typeNameKeysBySubgraphMap) {
-      typeNames: for (const [typeName, keys] of typeNameKeys) {
-        for (const key of keys.sort(
-          (a, b) =>
-            // sort by shorter keys first
-            // TODO: respect canonical keys
-            a.length - b.length,
-        )) {
-          if (types.has(typeName)) {
-            // type already constructed to be resolved by global object identification
-            // with the best key, skip it in all other occurrences
-            continue typeNames;
-          }
-
-          if (
-            // the key for fetching this object contains other objects
-            key.includes('{') ||
-            // the key for fetching this object contains arguments
-            key.includes('(')
-          ) {
-            // it's too complex to use global object identification
-            // TODO: do it anyways when need arises
-            continue;
-          }
-          if (key.includes(':')) {
-            throw new Error(
-              'Aliases in @key fields are not supported by Global Object Identification yet.',
-            );
-          }
-
-          // what we're left in the "key" are simple field(s) like "id" or "email"
-          const keyFieldNames = key.trim().split(/\s+/);
-          if (keyFieldNames.includes(nodeIdField)) {
-            throw new Error(
-              `The field "${nodeIdField}" is reserved for Global Object Identification and cannot be used in @key fields for type "${typeName}".`,
-            );
-          }
-
-          const schema = subschemas.find(
-            (s) => s.name === subgraphName,
-          )?.schema;
-          if (!schema) {
-            throw new Error(
-              `Subgraph "${subgraphName}" not found for Global Object Identification.`,
-            );
-          }
-
-          const objectInSubgraph = schema.getType(
-            typeName,
-          ) as GraphQLObjectType;
-          const fieldsOfObjectInSubgraph = objectInSubgraph.getFields();
-
-          const object = new GraphQLObjectType({
-            name: typeName,
-            interfaces: [nodeInterface],
-            fields: () => ({
-              [nodeIdField]: {
-                description:
-                  'A globally unique identifier. Can be used in various places throughout the system to identify this single value.',
-                type: new GraphQLNonNull(GraphQLID),
-                // NOTE: resolve function is not necessary here because Query.node will provide all fields
-              },
-              ...keyFieldNames.reduce(
-                (acc, fieldName) => {
-                  const fieldInSubgraph = fieldsOfObjectInSubgraph[fieldName];
-                  if (!fieldInSubgraph) {
-                    throw new Error(
-                      `Field "${fieldName}" not found in type "${typeName}" in subgraph "${subgraphName}".`,
-                    );
-                  }
-                  return {
-                    ...acc,
-                    [fieldName]: {
-                      type: fieldInSubgraph.type,
-                      // NOTE: resolve function is not necessary for the rest of fields because this subgraph will never resolve them
-                    },
-                  };
-                },
-                {} as Record<string, GraphQLFieldConfig<unknown, unknown>>,
-              ),
-            }),
-          });
-
-          types.set(typeName, {
-            object,
-            keySelectionSet: `{ ${key} }`,
-            keyFieldNames,
-          });
-        }
-      }
-    }
-
-    const globalObjectIdentSubschema: SubschemaConfig = {
-      // TODO: make sure there is no conflict with other subschemas
-      name: 'global-object-identification',
-      merge: {
-        ...types.entries().reduce(
-          (acc, [typeName, { keySelectionSet, keyFieldNames }]) => ({
-            ...acc,
-            [typeName]: {
-              fieldName: 'node',
-              selectionSet: keySelectionSet,
-              args: (source) => {
-                if (keyFieldNames.length === 1) {
-                  // single field key
-                  return {
-                    [nodeIdField]: toGlobalId(
-                      typeName,
-                      source[keyFieldNames[0]!],
-                    ),
-                  };
-                }
-                // multiple fields key
-                const fields: Record<string, unknown> = {};
-                for (const fieldName of keyFieldNames) {
-                  // loop is faster than reduce
-                  fields[fieldName] = source[fieldName];
-                }
-                return {
-                  [nodeIdField]: toGlobalId(typeName, JSON.stringify(fields)),
-                };
-              },
-            },
-          }),
-          {} as Record<string, MergedTypeConfig>,
-        ),
-      },
-      schema: new GraphQLSchema({
-        types: types
-          .values()
-          .map(({ object }) => object)
-          .toArray(),
-        query: new GraphQLObjectType({
-          name: 'Query',
-          fields: () => ({
-            // TODO: nodes(ids: [ID!]!): [Node!]!
-            node: {
-              type: nodeInterface,
-              description: 'Fetches an object given its globally unique `ID`.',
-              args: {
-                [nodeIdField]: {
-                  type: new GraphQLNonNull(GraphQLID),
-                  description: 'The globally unique `ID`.',
-                },
-              },
-              resolve: (_source, args: { [nodeIdField]: string }) => {
-                const nodeId = args[nodeIdField];
-                const { id: idOrFields, type } = fromGlobalId(
-                  args[nodeIdField],
-                );
-                if (!idOrFields || !type) {
-                  return null;
-                }
-                const { keyFieldNames } = types.get(type) || {};
-                if (!keyFieldNames) {
-                  return null;
-                }
-                if (keyFieldNames.length === 1) {
-                  // single field key
-                  return {
-                    __typename: type,
-                    [nodeIdField]: nodeId,
-                    [keyFieldNames[0]!]: idOrFields,
-                  };
-                }
-                // multiple fields key
-                try {
-                  const fields: Record<string, unknown> = {};
-                  const idFields = JSON.parse(idOrFields);
-                  for (const fieldName of keyFieldNames) {
-                    // loop is faster than reduce
-                    fields[fieldName] = idFields[fieldName];
-                  }
-                  return {
-                    __typename: type,
-                    [nodeIdField]: nodeId,
-                    ...fields,
-                  };
-                } catch {
-                  return null;
-                }
-              },
-            },
-          }),
-        }),
-      }),
-    };
-
-    subschemas.push(globalObjectIdentSubschema);
-  }
-
   const defaultMerger = getDefaultFieldConfigMerger(true);
   const fieldConfigMerger: TypeMergingOptions['fieldConfigMerger'] = function (
     candidates: MergeFieldConfigCandidate[],
@@ -1759,20 +1545,35 @@ export function getStitchingOptionsFromSupergraphSdl(
       extraDefinitions.push(definition);
     }
   }
-  const additionalTypeDefs: DocumentNode = {
-    kind: Kind.DOCUMENT,
-    definitions: extraDefinitions,
-  };
   if (opts.onSubschemaConfig) {
     for (const subschema of subschemas) {
       opts.onSubschemaConfig(subschema as FederationSubschemaConfig);
     }
   }
+  const shouldGlobalObjectIdent =
+    opts.globalObjectIdentification && typeNameKeysBySubgraphMap.size;
   return {
     subschemas,
-    typeDefs: additionalTypeDefs,
+    typeDefs: {
+      kind: Kind.DOCUMENT,
+      definitions: !shouldGlobalObjectIdent
+        ? extraDefinitions
+        : [
+            ...extraDefinitions,
+            ...createNodeDefinitions({
+              nodeIdField: 'nodeId',
+              subschemas,
+            }),
+          ],
+    } as DocumentNode,
     assumeValid: true,
     assumeValidSDL: true,
+    resolvers: !shouldGlobalObjectIdent
+      ? undefined
+      : createResolvers({
+          nodeIdField: 'nodeId',
+          subschemas,
+        }),
     typeMergingOptions: {
       useNonNullableFieldOnConflict: true,
       validationSettings: {
@@ -1946,3 +1747,10 @@ function mergeResults(results: unknown[], getFieldNames: () => Set<string>) {
   }
   return null;
 }
+
+export type MergedTypeConfigFromEntities = Required<
+  Pick<
+    MergedTypeConfig,
+    'selectionSet' | 'argsFromKeys' | 'key' | 'fieldName' | 'dataLoaderOptions'
+  >
+>;
diff --git a/packages/federation/tests/global-object-identification.test.ts b/packages/federation/tests/globalObjectIdentification.test.ts
similarity index 87%
rename from packages/federation/tests/global-object-identification.test.ts
rename to packages/federation/tests/globalObjectIdentification.test.ts
index 5d8240e31..14cc6a7ef 100644
--- a/packages/federation/tests/global-object-identification.test.ts
+++ b/packages/federation/tests/globalObjectIdentification.test.ts
@@ -155,6 +155,41 @@ describe('Global Object Identification', () => {
     `);
   });
 
+  it('should not resolve single field key object from globally unique node when doesnt exist', async () => {
+    const schema = await getStitchedSchemaFromLocalSchemas({
+      globalObjectIdentification: true,
+      localSchemas: {
+        accounts,
+      },
+    });
+
+    await expect(
+      Promise.resolve(
+        normalizedExecutor({
+          schema,
+          document: parse(/* GraphQL */ `
+        {
+          node(nodeId: "${toGlobalId('Account', 'dontexist1')}") {
+            nodeId
+            ... on Account {
+              id
+              name
+              email
+            }
+          }
+        }
+      `),
+        }),
+      ),
+    ).resolves.toMatchInlineSnapshot(`
+      {
+        "data": {
+          "node": null,
+        },
+      }
+    `);
+  });
+
   it('should resolve multiple fields key object from globally unique node', async () => {
     const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,

From b5cdb7cdd08d9108932ea634aed0374306e419a5 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Wed, 11 Jun 2025 13:36:07 +0200
Subject: [PATCH 20/44] handle remainders

---
 .../src/globalObjectIdentification.ts         | 117 +++++++++++++-----
 1 file changed, 86 insertions(+), 31 deletions(-)

diff --git a/packages/federation/src/globalObjectIdentification.ts b/packages/federation/src/globalObjectIdentification.ts
index 870bc2032..44749a738 100644
--- a/packages/federation/src/globalObjectIdentification.ts
+++ b/packages/federation/src/globalObjectIdentification.ts
@@ -62,7 +62,7 @@ export function createNodeDefinitions({
 
   // extend type X implements Node
 
-  for (const { typeName } of getResolveableTypes(subschemas)) {
+  for (const { typeName } of getDistinctResolvableTypes(subschemas)) {
     const typeExtensionDef: ObjectTypeExtensionNode = {
       kind: Kind.OBJECT_TYPE_EXTENSION,
       name: {
@@ -145,22 +145,61 @@ export function createResolvers({
   nodeIdField,
   subschemas,
 }: GlobalObjectIdentificationOptions): IResolvers {
-  const types = getResolveableTypesMap(subschemas);
+  const types = getDistinctResolvableTypes(subschemas).toArray();
   return {
+    ...types.reduce(
+      (resolvers, { typeName, keyFieldNames }) => ({
+        ...resolvers,
+        [typeName]: {
+          [nodeIdField](source) {
+            if (keyFieldNames.length === 1) {
+              // single field key
+              return toGlobalId(typeName, source[keyFieldNames[0]!]);
+            }
+            // multiple fields key
+            const keyFields: Record<string, unknown> = {};
+            for (const fieldName of keyFieldNames) {
+              // loop is faster than reduce
+              keyFields[fieldName] = source[fieldName];
+            }
+            return toGlobalId(typeName, JSON.stringify(keyFields));
+          },
+        },
+      }),
+      {} as Record<string, IResolvers>,
+    ),
     Query: {
       node(_source, { nodeId }, context, info) {
-        const { id, type: typeName } = fromGlobalId(nodeId);
-        const { subschema, merge } = types[typeName] || {};
-        if (!subschema || !merge) {
-          return null;
+        const { id: idOrFields, type: typeName } = fromGlobalId(nodeId);
+        const type = types.find((t) => t.typeName === typeName);
+        if (!type) {
+          return null; // unknown type
         }
-        const { key, selectionSet, ...batchOpts } = merge;
+
+        const keyFields: Record<string, unknown> = {};
+        if (type.keyFieldNames.length === 1) {
+          // single field key
+          keyFields[type.keyFieldNames[0]!] = idOrFields;
+        } else {
+          // multiple fields key
+          try {
+            const idFields = JSON.parse(idOrFields);
+            for (const fieldName of type.keyFieldNames) {
+              // loop is faster than reduce
+              keyFields[fieldName] = idFields[fieldName];
+            }
+          } catch {
+            return null; // invalid JSON i.e. invalid global ID
+          }
+        }
+
         return batchDelegateToSchema({
-          ...batchOpts,
-          schema: subschema,
-          key: { __typename: typeName, id }, // TODO: use keys
+          ...type.merge,
           info,
           context,
+          schema: type.subschema,
+          selectionSet: undefined, // selectionSet is not needed here
+          key: { ...keyFields, __typename: typeName }, // we already have all the necessary keys
           valuesFromResults: (results) =>
             // add the nodeId field to the results
             results.map((r: any) =>
@@ -169,17 +208,27 @@ export function createResolvers({
         });
       },
     },
-    Account: {
-      [nodeIdField](source) {
-        return toGlobalId('Account', source.id); // TODO: use keys
-      },
-    },
   };
 }
 
-function* getResolveableTypes(subschemas: Iterable<SubschemaConfig>) {
+function* getDistinctResolvableTypes(subschemas: Iterable<SubschemaConfig>) {
+  const yieldedTypes = new Set<string>();
   for (const subschema of subschemas) {
-    for (const [typeName, merge] of Object.entries(subschema.merge || {})) {
+    // TODO: respect canonical types
+    for (const [typeName, merge] of Object.entries(subschema.merge || {})
+      .filter(
+        // make sure selectionset is defined for the sort to work
+        ([, merge]) => merge.selectionSet,
+      )
+      .sort(
+        // sort by shortest keys first
+        ([, a], [, b]) => a.selectionSet!.length - b.selectionSet!.length,
+      )) {
+      if (yieldedTypes.has(typeName)) {
+        // already yielded this type, all types can only have one resolution
+        continue;
+      }
+
       if (
         !merge.selectionSet ||
         !merge.argsFromKeys ||
@@ -187,27 +236,33 @@ function* getResolveableTypes(subschemas: Iterable<SubschemaConfig>) {
         !merge.fieldName ||
         !merge.dataLoaderOptions
       ) {
+        // cannot be resolved globally
         continue;
       }
-      // TODO: provide the best and shortest path type
+
+      // remove first and last characters from the selection set making up the key (curly braces, `{ id } -> id`)
+      const key = merge.selectionSet.trim().slice(1, -1).trim();
+      if (
+        // the key for fetching this object contains other objects
+        key.includes('{') ||
+        // the key for fetching this object contains arguments
+        key.includes('(') ||
+        // the key contains aliases
+        key.includes(':')
+      ) {
+        // it's too complex to use global object identification
+        // TODO: do it anyways when need arises
+        continue;
+      }
+      // what we're left in the "key" are simple field(s) like "id" or "email"
+
+      yieldedTypes.add(typeName);
       yield {
         typeName,
         subschema,
         merge: merge as MergedTypeConfigFromEntities,
+        keyFieldNames: key.trim().split(/\s+/),
       };
     }
   }
 }
-
-function getResolveableTypesMap(subschemas: Iterable<SubschemaConfig>) {
-  const types: Record<
-    string,
-    { subschema: SubschemaConfig; merge: MergedTypeConfigFromEntities }
-  > = {};
-  for (const { typeName, merge, subschema } of getResolveableTypes(
-    subschemas,
-  )) {
-    types[typeName] = { subschema, merge };
-  }
-  return types;
-}

From 5ec5fbf63cc30e8281773af6a840415083323d15 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Wed, 11 Jun 2025 13:43:23 +0200
Subject: [PATCH 21/44] batch deleg

---
 packages/federation/package.json | 1 +
 yarn.lock                        | 1 +
 2 files changed, 2 insertions(+)

diff --git a/packages/federation/package.json b/packages/federation/package.json
index 9febfa147..f37963643 100644
--- a/packages/federation/package.json
+++ b/packages/federation/package.json
@@ -38,6 +38,7 @@
     "graphql": "^14.0.0 || ^15.0.0 || ^16.0.0 || ^17.0.0"
   },
   "dependencies": {
+    "@graphql-tools/batch-delegate": "workspace:^",
     "@graphql-tools/delegate": "workspace:^",
     "@graphql-tools/executor": "^1.4.7",
     "@graphql-tools/executor-http": "workspace:^",
diff --git a/yarn.lock b/yarn.lock
index 49897f373..2b86aefea 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -5080,6 +5080,7 @@ __metadata:
     "@apollo/server": "npm:^4.12.2"
     "@apollo/server-gateway-interface": "npm:^1.1.1"
     "@apollo/subgraph": "npm:^2.11.0"
+    "@graphql-tools/batch-delegate": "workspace:^"
     "@graphql-tools/delegate": "workspace:^"
     "@graphql-tools/executor": "npm:^1.4.7"
     "@graphql-tools/executor-http": "workspace:^"

From 55c410f85d886734eb24d0d2903342eadba75560 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Wed, 11 Jun 2025 13:50:48 +0200
Subject: [PATCH 22/44] option

---
 packages/federation/src/managed-federation.ts |  1 +
 .../src/federation/supergraph.ts              |  2 ++
 .../fusion-runtime/src/unifiedGraphManager.ts |  6 ++++
 packages/runtime/src/createGatewayRuntime.ts  |  1 +
 packages/runtime/src/types.ts                 | 33 +++++++++++++++++++
 5 files changed, 43 insertions(+)

diff --git a/packages/federation/src/managed-federation.ts b/packages/federation/src/managed-federation.ts
index a17361a03..2f921be5c 100644
--- a/packages/federation/src/managed-federation.ts
+++ b/packages/federation/src/managed-federation.ts
@@ -309,6 +309,7 @@ export async function getStitchedSchemaFromManagedFederation(
         httpExecutorOpts: options.httpExecutorOpts,
         onSubschemaConfig: options.onSubschemaConfig,
         batch: options.batch,
+        globalObjectIdentification: options.globalObjectIdentification,
       }),
     };
   }
diff --git a/packages/fusion-runtime/src/federation/supergraph.ts b/packages/fusion-runtime/src/federation/supergraph.ts
index 7589136dd..28b3f3422 100644
--- a/packages/fusion-runtime/src/federation/supergraph.ts
+++ b/packages/fusion-runtime/src/federation/supergraph.ts
@@ -159,6 +159,7 @@ export const handleFederationSupergraph: UnifiedGraphHandler = function ({
   additionalTypeDefs: additionalTypeDefsFromConfig = [],
   additionalResolvers: additionalResolversFromConfig = [],
   logger,
+  globalObjectIdentification,
 }: UnifiedGraphHandlerOpts): UnifiedGraphHandlerResult {
   const additionalTypeDefs = [...asArray(additionalTypeDefsFromConfig)];
   const additionalResolvers = [...asArray(additionalResolversFromConfig)];
@@ -273,6 +274,7 @@ export const handleFederationSupergraph: UnifiedGraphHandler = function ({
         },
       });
     },
+    globalObjectIdentification,
   });
   const inContextSDK = getInContextSDK(
     executableUnifiedGraph,
diff --git a/packages/fusion-runtime/src/unifiedGraphManager.ts b/packages/fusion-runtime/src/unifiedGraphManager.ts
index c8f5b3379..9e31c3f60 100644
--- a/packages/fusion-runtime/src/unifiedGraphManager.ts
+++ b/packages/fusion-runtime/src/unifiedGraphManager.ts
@@ -68,6 +68,7 @@ export interface UnifiedGraphHandlerOpts {
   onDelegationPlanHooks?: OnDelegationPlanHook<any>[];
   onDelegationStageExecuteHooks?: OnDelegationStageExecuteHook<any>[];
   onDelegateHooks?: OnDelegateHook<unknown>[];
+  globalObjectIdentification?: boolean;
 
   logger?: Logger;
 }
@@ -107,6 +108,8 @@ export interface UnifiedGraphManagerOptions<TContext> {
   instrumentation?: () => Instrumentation | undefined;
 
   onUnifiedGraphChange?(newUnifiedGraph: GraphQLSchema): void;
+
+  globalObjectIdentification?: boolean;
 }
 
 export type Instrumentation = {
@@ -137,6 +140,7 @@ export class UnifiedGraphManager<TContext> implements AsyncDisposable {
   private lastLoadTime?: number;
   private executor?: Executor;
   private instrumentation: () => Instrumentation | undefined;
+  private globalObjectIdentification: boolean;
 
   constructor(private opts: UnifiedGraphManagerOptions<TContext>) {
     this.batch = opts.batch ?? true;
@@ -152,6 +156,7 @@ export class UnifiedGraphManager<TContext> implements AsyncDisposable {
         `Starting polling to Supergraph with interval ${millisecondsToStr(opts.pollingInterval)}`,
       );
     }
+    this.globalObjectIdentification = opts.globalObjectIdentification ?? false;
   }
 
   private ensureUnifiedGraph(): MaybePromise<GraphQLSchema> {
@@ -310,6 +315,7 @@ export class UnifiedGraphManager<TContext> implements AsyncDisposable {
         onDelegationStageExecuteHooks: this.onDelegationStageExecuteHooks,
         onDelegateHooks: this.opts.onDelegateHooks,
         logger: this.opts.transportContext?.logger,
+        globalObjectIdentification: this.globalObjectIdentification,
       });
       const transportExecutorStack = new AsyncDisposableStack();
       const onSubgraphExecute = getOnSubgraphExecute({
diff --git a/packages/runtime/src/createGatewayRuntime.ts b/packages/runtime/src/createGatewayRuntime.ts
index b6a90662e..42192e682 100644
--- a/packages/runtime/src/createGatewayRuntime.ts
+++ b/packages/runtime/src/createGatewayRuntime.ts
@@ -726,6 +726,7 @@ export function createGatewayRuntime<
       additionalResolvers: config.additionalResolvers as IResolvers[],
       instrumentation: () => instrumentation,
       batch: config.__experimental__batchDelegation,
+      globalObjectIdentification: config.globalObjectIdentification,
     });
     getSchema = () => unifiedGraphManager.getUnifiedGraph();
     readinessChecker = () => {
diff --git a/packages/runtime/src/types.ts b/packages/runtime/src/types.ts
index ebda1cc81..3f9d40fc7 100644
--- a/packages/runtime/src/types.ts
+++ b/packages/runtime/src/types.ts
@@ -193,6 +193,39 @@ export interface GatewayConfigSupergraph<
    * If {@link cache} is provided, the fetched {@link supergraph} will be cached setting the TTL to this interval in seconds.
    */
   pollingInterval?: number;
+  /**
+   * Add support for GraphQL Global Object Identification Specification  by adding a `Node`
+   * interface, `node(id: ID!): Node` and `nodes(ids: [ID!]!): [Node!]!` fields to the `Query` type.
+   *
+   * The `Node` interface will have a `nodeId` (not `id`!) field used as the global identifier. It
+   * is intentionally not `id` to avoid collisions with existing `id` fields in subgraphs.
+   *
+   * ```graphql
+   * """An object with a globally unique `ID`."""
+   * interface Node {
+   *   """
+   *   A globally unique identifier. Can be used in various places throughout the system to identify this single value.
+   *   """
+   *   nodeId: ID!
+   * }
+   *
+   * extend type Query {
+   *   """Fetches an object given its globally unique `ID`."""
+   *   node(
+   *     """The globally unique `ID`."""
+   *     nodeId: ID!
+   *   ): Node
+   *   """Fetches objects given their globally unique `ID`s."""
+   *   nodes(
+   *     """The globally unique `ID`s."""
+   *     nodeIds: [ID!]!
+   *   ): [Node!]!
+   * }
+   * ```
+   *
+   * @see https://graphql.org/learn/global-object-identification/
+   */
+  globalObjectIdentification?: boolean;
 }
 
 export interface GatewayConfigSubgraph<

From bff6b2b34d28d5e674244a355ad4749b65b3b69f Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Wed, 11 Jun 2025 14:37:24 +0200
Subject: [PATCH 23/44] merge resolvers

---
 packages/fusion-runtime/src/federation/supergraph.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/fusion-runtime/src/federation/supergraph.ts b/packages/fusion-runtime/src/federation/supergraph.ts
index 28b3f3422..c6698e184 100644
--- a/packages/fusion-runtime/src/federation/supergraph.ts
+++ b/packages/fusion-runtime/src/federation/supergraph.ts
@@ -10,7 +10,7 @@ import type {
   SubschemaConfig,
 } from '@graphql-tools/delegate';
 import { getStitchedSchemaFromSupergraphSdl } from '@graphql-tools/federation';
-import { mergeTypeDefs } from '@graphql-tools/merge';
+import { mergeResolvers, mergeTypeDefs } from '@graphql-tools/merge';
 import { createMergedTypeResolver } from '@graphql-tools/stitch';
 import { stitchingDirectives } from '@graphql-tools/stitching-directives';
 import {
@@ -212,7 +212,7 @@ export const handleFederationSupergraph: UnifiedGraphHandler = function ({
         additionalResolvers,
       );
       // @ts-expect-error - Typings are wrong
-      opts.resolvers = additionalResolvers;
+      opts.resolvers = mergeResolvers(opts.resolvers, additionalResolvers);
       // @ts-expect-error - Typings are wrong
       opts.inheritResolversFromInterfaces = true;
 

From 2a0ff2797842567748478b5a3ba2503cd73b4dae Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Wed, 11 Jun 2025 14:38:18 +0200
Subject: [PATCH 24/44] global object ident e2e

---
 .../gateway.config.ts                         |   5 +
 .../global-object-identification.e2e.ts       |  55 ++++++
 e2e/global-object-identification/package.json |   7 +
 .../gateway.config.ts                         |  43 -----
 e2e/relay-additional-resolvers/gw.out         | 173 ------------------
 e2e/relay-additional-resolvers/id.ts          |  20 --
 e2e/relay-additional-resolvers/package.json   |   9 -
 .../relay-additional-resolvers.e2e.ts         |  53 ------
 .../services/posts.ts                         |  56 ------
 .../services/users.ts                         |  54 ------
 yarn.lock                                     |  20 +-
 11 files changed, 76 insertions(+), 419 deletions(-)
 create mode 100644 e2e/global-object-identification/gateway.config.ts
 create mode 100644 e2e/global-object-identification/global-object-identification.e2e.ts
 create mode 100644 e2e/global-object-identification/package.json
 delete mode 100644 e2e/relay-additional-resolvers/gateway.config.ts
 delete mode 100644 e2e/relay-additional-resolvers/gw.out
 delete mode 100644 e2e/relay-additional-resolvers/id.ts
 delete mode 100644 e2e/relay-additional-resolvers/package.json
 delete mode 100644 e2e/relay-additional-resolvers/relay-additional-resolvers.e2e.ts
 delete mode 100644 e2e/relay-additional-resolvers/services/posts.ts
 delete mode 100644 e2e/relay-additional-resolvers/services/users.ts

diff --git a/e2e/global-object-identification/gateway.config.ts b/e2e/global-object-identification/gateway.config.ts
new file mode 100644
index 000000000..628bd3582
--- /dev/null
+++ b/e2e/global-object-identification/gateway.config.ts
@@ -0,0 +1,5 @@
+import { defineConfig } from '@graphql-hive/gateway';
+
+export const gatewayConfig = defineConfig({
+  globalObjectIdentification: true,
+});
diff --git a/e2e/global-object-identification/global-object-identification.e2e.ts b/e2e/global-object-identification/global-object-identification.e2e.ts
new file mode 100644
index 000000000..6777e46e9
--- /dev/null
+++ b/e2e/global-object-identification/global-object-identification.e2e.ts
@@ -0,0 +1,55 @@
+import { createExampleSetup, createTenv } from '@internal/e2e';
+import { toGlobalId } from 'graphql-relay';
+import { expect, it } from 'vitest';
+
+const { gateway } = createTenv(__dirname);
+const { supergraph, query, result } = createExampleSetup(__dirname);
+
+it('should execute as usual', async () => {
+  const { execute } = await gateway({
+    supergraph: await supergraph(),
+  });
+  await expect(
+    execute({
+      query,
+    }),
+  ).resolves.toEqual(result);
+});
+
+it('should find objects through node', async () => {
+  const { execute } = await gateway({
+    supergraph: await supergraph(),
+  });
+  await expect(
+    execute({
+      query: /* GraphQL */ `
+        query ($nodeId: ID!) {
+          node(nodeId: $nodeId) {
+            ... on Product {
+              nodeId
+              upc
+              name
+              price
+              weight
+            }
+          }
+        }
+      `,
+      variables: {
+        nodeId: toGlobalId('Product', '2'),
+      },
+    }),
+  ).resolves.toMatchInlineSnapshot(`
+    {
+      "data": {
+        "node": {
+          "name": "Couch",
+          "nodeId": "UHJvZHVjdDoy",
+          "price": 1299,
+          "upc": "2",
+          "weight": 1000,
+        },
+      },
+    }
+  `);
+});
diff --git a/e2e/global-object-identification/package.json b/e2e/global-object-identification/package.json
new file mode 100644
index 000000000..686278497
--- /dev/null
+++ b/e2e/global-object-identification/package.json
@@ -0,0 +1,7 @@
+{
+  "name": "@e2e/global-object-identification",
+  "private": true,
+  "dependencies": {
+    "graphql-relay": "^0.10.2"
+  }
+}
diff --git a/e2e/relay-additional-resolvers/gateway.config.ts b/e2e/relay-additional-resolvers/gateway.config.ts
deleted file mode 100644
index 669a03551..000000000
--- a/e2e/relay-additional-resolvers/gateway.config.ts
+++ /dev/null
@@ -1,43 +0,0 @@
-import { defineConfig } from '@graphql-hive/gateway';
-import { decodeGlobalID } from './id';
-
-export const gatewayConfig = defineConfig({
-  additionalTypeDefs: /* GraphQL */ `
-    type Query {
-      node(id: ID!): Node
-      nodes(ids: [ID!]!): [Node]!
-    }
-  `,
-  additionalResolvers: {
-    Query: {
-      node(_source: any, args: { id: string }, _context: any, _info: any) {
-        const { type, localID } = decodeGlobalID(args.id);
-        return {
-          __typename: type,
-          id: localID,
-        };
-      },
-      nodes(_source: any, args: { ids: string[] }, _context: any, _info: any) {
-        return args.ids.map((id) => {
-          const { type, localID } = decodeGlobalID(id);
-          return {
-            __typename: type,
-            id: localID,
-          };
-        });
-      },
-      _entities: (_: any, { representations }: any) => {
-        return representations.map((ref) => {
-          // Since all our entities just need id, we can return the reference as is
-          // The __typename is already included in the reference
-          return ref;
-        });
-      },
-    },
-    Node: {
-      __resolveType(source: { __typename: string }) {
-        return source.__typename;
-      },
-    },
-  },
-});
diff --git a/e2e/relay-additional-resolvers/gw.out b/e2e/relay-additional-resolvers/gw.out
deleted file mode 100644
index 16295a523..000000000
--- a/e2e/relay-additional-resolvers/gw.out
+++ /dev/null
@@ -1,173 +0,0 @@
-[2025-05-26T14:55:36.564Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fshFt7ol/supergraph.graphql 
-[2025-05-26T14:55:36.566Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fshFt7ol/supergraph.graphql 
-[2025-05-26T14:55:36.566Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fshFt7ol/supergraph.graphql for changes 
-[2025-05-26T14:55:36.569Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fshFt7ol/supergraph.graphql 
-[2025-05-26T14:55:36.579Z] INFO   Listening on http://localhost:60575 
-[2025-05-26T14:56:42.380Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
-[2025-05-26T14:56:42.387Z] INFO   Loaded config 
-[2025-05-26T14:56:42.387Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsdxRzJ4/supergraph.graphql 
-[2025-05-26T14:56:42.388Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsdxRzJ4/supergraph.graphql 
-[2025-05-26T14:56:42.388Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsdxRzJ4/supergraph.graphql for changes 
-[2025-05-26T14:56:42.390Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsdxRzJ4/supergraph.graphql 
-[2025-05-26T14:56:42.397Z] INFO   Listening on http://localhost:60714 
-[2025-05-26T14:56:42.610Z] ERROR  Error: Query.node defined in resolvers, but not in schema
-    at addResolversToSchema (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/schema/esm/addResolversToSchema.js:80:39)
-    at stitchSchemas (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/stitch/src/stitchSchemas.ts:136:12)
-    at getStitchedSchemaFromSupergraphSdl (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/federation/src/supergraph.ts:1524:26)
-    at UnifiedGraphManager.handleFederationSupergraph (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/fusion-runtime/src/federation/supergraph.ts:188:32)
-    at UnifiedGraphManager.handleLoadedUnifiedGraph (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/fusion-runtime/src/unifiedGraphManager.ts:302:16)
-    at <anonymous> (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/fusion-runtime/src/unifiedGraphManager.ts:388:14) 
-[2025-05-26T14:56:42.614Z] ERROR  Error: Query.node defined in resolvers, but not in schema
-    at addResolversToSchema (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/schema/esm/addResolversToSchema.js:80:39)
-    at stitchSchemas (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/stitch/src/stitchSchemas.ts:136:12)
-    at getStitchedSchemaFromSupergraphSdl (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/federation/src/supergraph.ts:1524:26)
-    at UnifiedGraphManager.handleFederationSupergraph (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/fusion-runtime/src/federation/supergraph.ts:188:32)
-    at UnifiedGraphManager.handleLoadedUnifiedGraph (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/fusion-runtime/src/unifiedGraphManager.ts:302:16)
-    at <anonymous> (/Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/packages/fusion-runtime/src/unifiedGraphManager.ts:388:14) 
-[2025-05-26T14:57:52.746Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
-[2025-05-26T14:57:52.753Z] INFO   Loaded config 
-[2025-05-26T14:57:52.753Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsYpodCQ/supergraph.graphql 
-[2025-05-26T14:57:52.754Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsYpodCQ/supergraph.graphql 
-[2025-05-26T14:57:52.754Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsYpodCQ/supergraph.graphql for changes 
-[2025-05-26T14:57:52.756Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsYpodCQ/supergraph.graphql 
-[2025-05-26T14:57:52.762Z] INFO   Listening on http://localhost:60826 
-[2025-05-26T14:57:53.026Z] ERROR  Error: Cannot query field "node" on type "Query".
-    at Object.node (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts:13:15)
-    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:351:24)
-    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
-    at executeOperation (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:260:18)
-    at file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:64:37
-    at Promise.then (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@whatwg-node/promise-helpers/esm/index.js:34:40)
-    at handleMaybePromise (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@whatwg-node/promise-helpers/esm/index.js:10:33)
-    at executeImpl (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:64:12)
-    at execute (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:49:12)
-    at file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/normalizedExecutor.js:13:37 {
-  path: [ 'node' ],
-  locations: [ { line: 3, column: 11 } ],
-  extensions: [Object: null prototype] {}
-} 
-[2025-05-26T15:01:11.667Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
-[2025-05-26T15:01:11.674Z] INFO   Loaded config 
-[2025-05-26T15:01:11.674Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsJCufQu/supergraph.graphql 
-[2025-05-26T15:01:11.675Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsJCufQu/supergraph.graphql 
-[2025-05-26T15:01:11.675Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsJCufQu/supergraph.graphql for changes 
-[2025-05-26T15:01:11.678Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsJCufQu/supergraph.graphql 
-[2025-05-26T15:01:11.685Z] INFO   Listening on http://localhost:61090 
-[2025-05-26T15:02:08.930Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
-[2025-05-26T15:02:08.939Z] INFO   Loaded config 
-[2025-05-26T15:02:08.939Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fs9Hcusc/supergraph.graphql 
-[2025-05-26T15:02:08.940Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fs9Hcusc/supergraph.graphql 
-[2025-05-26T15:02:08.940Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fs9Hcusc/supergraph.graphql for changes 
-[2025-05-26T15:02:08.942Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fs9Hcusc/supergraph.graphql 
-[2025-05-26T15:02:08.948Z] INFO   Listening on http://localhost:61194 
-[2025-05-26T15:02:30.927Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
-[2025-05-26T15:02:30.935Z] INFO   Loaded config 
-[2025-05-26T15:02:30.935Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfZc8xM/supergraph.graphql 
-[2025-05-26T15:02:30.936Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfZc8xM/supergraph.graphql 
-[2025-05-26T15:02:30.936Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfZc8xM/supergraph.graphql for changes 
-[2025-05-26T15:02:30.938Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfZc8xM/supergraph.graphql 
-[2025-05-26T15:02:30.944Z] INFO   Listening on http://localhost:61257 
-{ id: 'VXNlcjp1c2VyLTI=' }
-[2025-05-26T15:02:31.187Z] ERROR  Error: Cannot query field "node" on type "Query".
-    at Object.node (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts:14:15)
-    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:351:24)
-    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
-    at executeOperation (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:260:18)
-    at file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:64:37
-    at Promise.then (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@whatwg-node/promise-helpers/esm/index.js:34:40)
-    at handleMaybePromise (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@whatwg-node/promise-helpers/esm/index.js:10:33)
-    at executeImpl (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:64:12)
-    at execute (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:49:12)
-    at file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/normalizedExecutor.js:13:37 {
-  path: [ 'node' ],
-  locations: [ { line: 3, column: 11 } ],
-  extensions: [Object: null prototype] {}
-} 
-[2025-05-26T15:04:08.181Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
-[2025-05-26T15:04:08.191Z] INFO   Loaded config 
-[2025-05-26T15:04:08.191Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fstEv1aL/supergraph.graphql 
-[2025-05-26T15:04:08.191Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fstEv1aL/supergraph.graphql 
-[2025-05-26T15:04:08.191Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fstEv1aL/supergraph.graphql for changes 
-[2025-05-26T15:04:08.194Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fstEv1aL/supergraph.graphql 
-[2025-05-26T15:04:08.200Z] INFO   Listening on http://localhost:61412 
-[2025-05-26T15:04:08.458Z] ERROR  Error: Cannot return null for non-nullable field User.name.
-    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:467:19)
-    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
-    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
-    at collectAndExecuteSubfields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:736:23)
-    at completeObjectValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:726:12)
-    at completeAbstractValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:675:12)
-    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:487:16)
-    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
-    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
-    at executeOperation (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:260:18) {
-  path: [ 'node', 'name' ],
-  locations: [ { line: 5, column: 15 } ],
-  extensions: [Object: null prototype] {}
-} 
-[2025-05-26T15:05:46.728Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
-[2025-05-26T15:05:46.738Z] INFO   Loaded config 
-[2025-05-26T15:05:46.738Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fskLgGRP/supergraph.graphql 
-[2025-05-26T15:05:46.739Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fskLgGRP/supergraph.graphql 
-[2025-05-26T15:05:46.739Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fskLgGRP/supergraph.graphql for changes 
-[2025-05-26T15:05:46.741Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fskLgGRP/supergraph.graphql 
-[2025-05-26T15:05:46.747Z] INFO   Listening on http://localhost:61572 
-[2025-05-26T15:05:47.016Z] ERROR  Error: Cannot return null for non-nullable field User.name.
-    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:467:19)
-    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
-    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
-    at collectAndExecuteSubfields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:736:23)
-    at completeObjectValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:726:12)
-    at completeAbstractValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:675:12)
-    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:487:16)
-    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
-    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
-    at executeOperation (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:260:18) {
-  path: [ 'node', 'name' ],
-  locations: [ { line: 5, column: 15 } ],
-  extensions: [Object: null prototype] {}
-} 
-[2025-05-26T15:09:42.499Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
-[2025-05-26T15:09:42.508Z] INFO   Loaded config 
-[2025-05-26T15:09:42.508Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsOwxhFd/supergraph.graphql 
-[2025-05-26T15:09:42.509Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsOwxhFd/supergraph.graphql 
-[2025-05-26T15:09:42.509Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsOwxhFd/supergraph.graphql for changes 
-[2025-05-26T15:09:42.511Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsOwxhFd/supergraph.graphql 
-[2025-05-26T15:09:42.517Z] INFO   Listening on http://localhost:61887 
-[2025-05-26T15:09:42.786Z] ERROR  Error: Cannot return null for non-nullable field User.name.
-    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:467:19)
-    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
-    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
-    at collectAndExecuteSubfields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:736:23)
-    at completeObjectValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:726:12)
-    at completeAbstractValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:675:12)
-    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:487:16)
-    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
-    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
-    at executeOperation (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:260:18) {
-  path: [ 'node', 'name' ],
-  locations: [ { line: 5, column: 15 } ],
-  extensions: [Object: null prototype] {}
-} 
-[2025-05-26T15:12:09.330Z] INFO   Found default config file /Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/e2e/relay-additional-resolvers/gateway.config.ts 
-[2025-05-26T15:12:09.342Z] INFO   Loaded config 
-[2025-05-26T15:12:09.343Z] INFO   Supergraph will be loaded from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfAkQmK/supergraph.graphql 
-[2025-05-26T15:12:09.343Z] INFO   Reading supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfAkQmK/supergraph.graphql 
-[2025-05-26T15:12:09.343Z] INFO   Watching /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfAkQmK/supergraph.graphql for changes 
-[2025-05-26T15:12:09.346Z] INFO   Serving local supergraph from /var/folders/x_/ly8bj5d97ks505gzsxc49_vr0000gn/T/hive-gateway_e2e_fsfAkQmK/supergraph.graphql 
-[2025-05-26T15:12:09.352Z] INFO   Listening on http://localhost:62107 
-[2025-05-26T15:12:09.626Z] ERROR  Error: Cannot return null for non-nullable field User.name.
-    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:467:19)
-    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
-    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
-    at collectAndExecuteSubfields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:736:23)
-    at completeObjectValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:726:12)
-    at completeAbstractValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:675:12)
-    at completeValue (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:487:16)
-    at executeField (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:357:25)
-    at executeFields (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:296:28)
-    at executeOperation (file:///Users/enisdenjo/Develop/src/github.com/graphql-hive/gateway/node_modules/@graphql-tools/executor/esm/execution/execute.js:260:18) {
-  path: [ 'node', 'name' ],
-  locations: [ { line: 5, column: 15 } ],
-  extensions: [Object: null prototype] {}
-} 
diff --git a/e2e/relay-additional-resolvers/id.ts b/e2e/relay-additional-resolvers/id.ts
deleted file mode 100644
index 79c91eb09..000000000
--- a/e2e/relay-additional-resolvers/id.ts
+++ /dev/null
@@ -1,20 +0,0 @@
-/**
- * Encodes a type and local ID into a global ID
- * @param type - The type of the entity (e.g., "Person", "Story")
- * @param localID - The local ID of the entity
- * @returns Base64 encoded global ID
- */
-export function encodeGlobalID(type: string, localID: string) {
-  return Buffer.from(JSON.stringify([type, localID])).toString('base64');
-}
-
-/**
- * Decodes a global ID into its type and local ID components
- * @param globalID - The base64 encoded global ID
- * @returns Object containing type and local ID
- */
-export function decodeGlobalID(globalID: string) {
-  const decoded = Buffer.from(globalID, 'base64').toString('utf-8');
-  const [type, localID] = JSON.parse(decoded) as [string, string];
-  return { type, localID };
-}
diff --git a/e2e/relay-additional-resolvers/package.json b/e2e/relay-additional-resolvers/package.json
deleted file mode 100644
index e5b4dfb9e..000000000
--- a/e2e/relay-additional-resolvers/package.json
+++ /dev/null
@@ -1,9 +0,0 @@
-{
-  "name": "@e2e/relay-additional-resolvers",
-  "private": true,
-  "dependencies": {
-    "@apollo/subgraph": "^2.10.0",
-    "graphql": "^16.9.0",
-    "graphql-sse": "^2.5.3"
-  }
-}
diff --git a/e2e/relay-additional-resolvers/relay-additional-resolvers.e2e.ts b/e2e/relay-additional-resolvers/relay-additional-resolvers.e2e.ts
deleted file mode 100644
index b9e90fb2e..000000000
--- a/e2e/relay-additional-resolvers/relay-additional-resolvers.e2e.ts
+++ /dev/null
@@ -1,53 +0,0 @@
-import { createTenv } from '@internal/e2e';
-import { expect, it } from 'vitest';
-import { encodeGlobalID } from './id';
-
-const { gateway, service } = createTenv(__dirname);
-
-it('should resolve the data behind the node', async () => {
-  const { execute } = await gateway({
-    pipeLogs: 'gw.out',
-    supergraph: {
-      with: 'apollo',
-      services: [await service('users'), await service('posts')],
-    },
-  });
-
-  await expect(
-    execute({
-      query: /* GraphQL */ `
-        query ($id: ID!) {
-          node(id: $id) {
-            ... on User {
-              name
-              posts {
-                title
-                content
-              }
-            }
-          }
-        }
-      `,
-      variables: {
-        id: encodeGlobalID('User', 'user-2'),
-      },
-    }),
-  ).resolves.toMatchInlineSnapshot(`
-    {
-      "errors": [
-        {
-          "extensions": {
-            "code": "GRAPHQL_VALIDATION_FAILED",
-          },
-          "locations": [
-            {
-              "column": 11,
-              "line": 3,
-            },
-          ],
-          "message": "Cannot query field "node" on type "Query".",
-        },
-      ],
-    }
-  `);
-});
diff --git a/e2e/relay-additional-resolvers/services/posts.ts b/e2e/relay-additional-resolvers/services/posts.ts
deleted file mode 100644
index fd3557053..000000000
--- a/e2e/relay-additional-resolvers/services/posts.ts
+++ /dev/null
@@ -1,56 +0,0 @@
-import { createServer } from 'http';
-import { buildSubgraphSchema } from '@apollo/subgraph';
-import { Opts } from '@internal/testing';
-import { parse } from 'graphql';
-import { createYoga } from 'graphql-yoga';
-
-const posts: { id: string; title: string; content: string }[] = [
-  {
-    id: 'post-1',
-    title: 'Hello world',
-    content: 'This is a post',
-  },
-  {
-    id: 'post-2',
-    title: 'Hello again',
-    content: 'This is another post',
-  },
-  {
-    id: 'post-3',
-    title: 'Hello again again',
-    content: 'This is another post again',
-  },
-];
-
-const typeDefs = parse(/* GraphQL */ `
-  type Query {
-    hello: String!
-  }
-  interface Node {
-    id: ID!
-  }
-  type Post implements Node @key(fields: "id") {
-    id: ID!
-    title: String!
-    content: String!
-  }
-`);
-
-const resolvers = {
-  Query: {
-    hello: () => 'world',
-  },
-  Post: {
-    __resolveReference(post: { id: string }) {
-      return posts.find((p) => p.id === post.id);
-    },
-  },
-};
-
-const yoga = createYoga({
-  schema: buildSubgraphSchema([{ typeDefs, resolvers }]),
-});
-
-const opts = Opts(process.argv);
-
-createServer(yoga).listen(opts.getServicePort('posts'));
diff --git a/e2e/relay-additional-resolvers/services/users.ts b/e2e/relay-additional-resolvers/services/users.ts
deleted file mode 100644
index dbcf214ff..000000000
--- a/e2e/relay-additional-resolvers/services/users.ts
+++ /dev/null
@@ -1,54 +0,0 @@
-import { createServer } from 'http';
-import { buildSubgraphSchema } from '@apollo/subgraph';
-import { Opts } from '@internal/testing';
-import { parse } from 'graphql';
-import { createYoga } from 'graphql-yoga';
-
-const users: { id: string; name: string; posts: { id: string }[] }[] = [
-  {
-    id: 'user-1',
-    name: 'John Doe',
-    posts: [{ id: 'post-2' }],
-  },
-  {
-    id: 'user-2',
-    name: 'Jane Doe',
-    posts: [{ id: 'post-3' }, { id: 'post-1' }],
-  },
-];
-
-const typeDefs = parse(/* GraphQL */ `
-  type Query {
-    hello: String!
-  }
-  interface Node {
-    id: ID!
-  }
-  type User implements Node @key(fields: "id") {
-    id: ID!
-    name: String!
-    posts: [Post!]!
-  }
-  type Post implements Node {
-    id: ID!
-  }
-`);
-
-const resolvers = {
-  Query: {
-    hello: () => 'world',
-  },
-  User: {
-    __resolveReference(user: { id: string }) {
-      return users.find((u) => u.id === user.id);
-    },
-  },
-};
-
-const yoga = createYoga({
-  schema: buildSubgraphSchema([{ typeDefs, resolvers }]),
-});
-
-const opts = Opts(process.argv);
-
-createServer(yoga).listen(opts.getServicePort('users'));
diff --git a/yarn.lock b/yarn.lock
index 2b86aefea..70c38ad14 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -397,7 +397,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@apollo/subgraph@npm:^2.10.0, @apollo/subgraph@npm:^2.11.0":
+"@apollo/subgraph@npm:^2.11.0":
   version: 2.11.0
   resolution: "@apollo/subgraph@npm:2.11.0"
   dependencies:
@@ -3062,6 +3062,14 @@ __metadata:
   languageName: unknown
   linkType: soft
 
+"@e2e/global-object-identification@workspace:e2e/global-object-identification":
+  version: 0.0.0-use.local
+  resolution: "@e2e/global-object-identification@workspace:e2e/global-object-identification"
+  dependencies:
+    graphql-relay: "npm:^0.10.2"
+  languageName: unknown
+  linkType: soft
+
 "@e2e/graceful-shutdown@workspace:e2e/graceful-shutdown":
   version: 0.0.0-use.local
   resolution: "@e2e/graceful-shutdown@workspace:e2e/graceful-shutdown"
@@ -3356,16 +3364,6 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@e2e/relay-additional-resolvers@workspace:e2e/relay-additional-resolvers":
-  version: 0.0.0-use.local
-  resolution: "@e2e/relay-additional-resolvers@workspace:e2e/relay-additional-resolvers"
-  dependencies:
-    "@apollo/subgraph": "npm:^2.10.0"
-    graphql: "npm:^16.9.0"
-    graphql-sse: "npm:^2.5.3"
-  languageName: unknown
-  linkType: soft
-
 "@e2e/retry-timeout@workspace:e2e/retry-timeout":
   version: 0.0.0-use.local
   resolution: "@e2e/retry-timeout@workspace:e2e/retry-timeout"

From c77d0ea27c55be1f6a6ce02efec5f2854cf757b4 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Wed, 11 Jun 2025 17:47:32 +0200
Subject: [PATCH 25/44] specify return type

---
 packages/federation/src/globalObjectIdentification.ts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/packages/federation/src/globalObjectIdentification.ts b/packages/federation/src/globalObjectIdentification.ts
index 44749a738..315804925 100644
--- a/packages/federation/src/globalObjectIdentification.ts
+++ b/packages/federation/src/globalObjectIdentification.ts
@@ -4,6 +4,7 @@ import { IResolvers } from '@graphql-tools/utils';
 import {
   DefinitionNode,
   FieldDefinitionNode,
+  GraphQLObjectType,
   InterfaceTypeDefinitionNode,
   Kind,
   ObjectTypeExtensionNode,
@@ -198,6 +199,9 @@ export function createResolvers({
           info,
           context,
           schema: type.subschema,
+          returnType: type.subschema.schema.getType(typeName) as
+            | GraphQLObjectType
+            | undefined, // shouldnt ever be undefined
           selectionSet: undefined, // selectionSet is not needed here
           key: { ...keyFields, __typename: typeName }, // we already have all the necessary keys
           valuesFromResults: (results) =>

From c3c5449a1ef56ee324e2f3db8093b2de799c1889 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Thu, 12 Jun 2025 10:24:55 +0200
Subject: [PATCH 26/44] resolve from other subgraphs too

---
 .../tests/globalObjectIdentification.test.ts  | 64 +++++++++++++++++++
 1 file changed, 64 insertions(+)

diff --git a/packages/federation/tests/globalObjectIdentification.test.ts b/packages/federation/tests/globalObjectIdentification.test.ts
index 14cc6a7ef..67588426a 100644
--- a/packages/federation/tests/globalObjectIdentification.test.ts
+++ b/packages/federation/tests/globalObjectIdentification.test.ts
@@ -15,6 +15,12 @@ describe('Global Object Identification', () => {
         email: 'john@doe.com',
       },
     ],
+    auth: [
+      {
+        id: 'a1',
+        isVerified: true,
+      },
+    ],
     people: [
       {
         firstName: 'John',
@@ -50,6 +56,20 @@ describe('Global Object Identification', () => {
     },
   });
 
+  const auth = buildSubgraphSchema({
+    typeDefs: parse(/* GraphQL */ `
+      type Account @key(fields: "id") {
+        id: ID!
+        isVerified: Boolean!
+      }
+    `),
+    resolvers: {
+      Account: {
+        __resolveReference: (ref) => data.auth.find((a) => a.id === ref.id),
+      },
+    },
+  });
+
   const people = buildSubgraphSchema({
     typeDefs: parse(/* GraphQL */ `
       type Query {
@@ -115,11 +135,53 @@ describe('Global Object Identification', () => {
     `);
   });
 
+  it('should resolve without node as usual', async () => {
+    const schema = await getStitchedSchemaFromLocalSchemas({
+      globalObjectIdentification: true,
+      localSchemas: {
+        accounts,
+        auth,
+      },
+    });
+
+    await expect(
+      Promise.resolve(
+        normalizedExecutor({
+          schema,
+          document: parse(/* GraphQL */ `
+            {
+              accounts {
+                id
+                name
+                email
+                isVerified
+              }
+            }
+          `),
+        }),
+      ),
+    ).resolves.toMatchInlineSnapshot(`
+      {
+        "data": {
+          "accounts": [
+            {
+              "email": "john@doe.com",
+              "id": "a1",
+              "isVerified": true,
+              "name": "John Doe",
+            },
+          ],
+        },
+      }
+    `);
+  });
+
   it('should resolve single field key object from globally unique node', async () => {
     const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,
       localSchemas: {
         accounts,
+        auth,
       },
     });
 
@@ -135,6 +197,7 @@ describe('Global Object Identification', () => {
               id
               name
               email
+              isVerified
             }
           }
         }
@@ -147,6 +210,7 @@ describe('Global Object Identification', () => {
           "node": {
             "email": "john@doe.com",
             "id": "a1",
+            "isVerified": true,
             "name": "John Doe",
             "nodeId": "QWNjb3VudDphMQ==",
           },

From d9d5509da191439847dd12ceda5dba24377b3e10 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Thu, 12 Jun 2025 13:46:32 +0200
Subject: [PATCH 27/44] correct returntype

---
 packages/batch-delegate/src/getLoader.ts      |  5 +++-
 .../src/globalObjectIdentification.ts         | 27 ++++++++++++-------
 2 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/packages/batch-delegate/src/getLoader.ts b/packages/batch-delegate/src/getLoader.ts
index 655be63b7..b5558f225 100644
--- a/packages/batch-delegate/src/getLoader.ts
+++ b/packages/batch-delegate/src/getLoader.ts
@@ -21,7 +21,10 @@ function createBatchFn<K = any>(options: BatchDelegateOptions) {
       .then(() =>
         delegateToSchema({
           returnType: new GraphQLList(
-            getNamedType(options.returnType || options.info.returnType),
+            getNamedType(
+              // options.returnType || // if the returnType is provided by options, it'll override this property because of the spread below. it was like this since forever, so lets keep it for backwards compatibility
+              options.info.returnType,
+            ),
           ),
           onLocatedError: (originalError) => {
             if (originalError.path == null) {
diff --git a/packages/federation/src/globalObjectIdentification.ts b/packages/federation/src/globalObjectIdentification.ts
index 315804925..8b6d30d42 100644
--- a/packages/federation/src/globalObjectIdentification.ts
+++ b/packages/federation/src/globalObjectIdentification.ts
@@ -1,9 +1,10 @@
 import { batchDelegateToSchema } from '@graphql-tools/batch-delegate';
-import { SubschemaConfig } from '@graphql-tools/delegate';
+import { StitchingInfo, SubschemaConfig } from '@graphql-tools/delegate';
 import { IResolvers } from '@graphql-tools/utils';
 import {
   DefinitionNode,
   FieldDefinitionNode,
+  GraphQLList,
   GraphQLObjectType,
   InterfaceTypeDefinitionNode,
   Kind,
@@ -171,6 +172,18 @@ export function createResolvers({
     ),
     Query: {
       node(_source, { nodeId }, context, info) {
+        const stitchingInfo = info.schema.extensions?.['stitchingInfo'] as
+          | StitchingInfo
+          | undefined;
+        if (!stitchingInfo) {
+          return null; // no stitching info, something went wrong // TODO: throw instead?
+        }
+
+        // we must use otherwise different schema
+        const types = getDistinctResolvableTypes(
+          stitchingInfo.subschemaMap.values(),
+        );
+
         const { id: idOrFields, type: typeName } = fromGlobalId(nodeId);
         const type = types.find((t) => t.typeName === typeName);
         if (!type) {
@@ -199,16 +212,12 @@ export function createResolvers({
           info,
           context,
           schema: type.subschema,
-          returnType: type.subschema.schema.getType(typeName) as
-            | GraphQLObjectType
-            | undefined, // shouldnt ever be undefined
+          returnType: new GraphQLList(
+            // wont ever be undefined, we ensured the subschema has the type above
+            type.subschema.schema.getType(typeName) as GraphQLObjectType,
+          ),
           selectionSet: undefined, // selectionSet is not needed here
           key: { ...keyFields, __typename: typeName }, // we already have all the necessary keys
-          valuesFromResults: (results) =>
-            // add the nodeId field to the results
-            results.map((r: any) =>
-              !r ? null : { ...r, [nodeIdField]: nodeId },
-            ),
         });
       },
     },

From 6f0c11a5189af7d18b48156ff81facddba2c34f8 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Thu, 12 Jun 2025 13:52:05 +0200
Subject: [PATCH 28/44] changeseet

---
 .changeset/rare-pants-develop.md | 47 ++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)
 create mode 100644 .changeset/rare-pants-develop.md

diff --git a/.changeset/rare-pants-develop.md b/.changeset/rare-pants-develop.md
new file mode 100644
index 000000000..24ffba25b
--- /dev/null
+++ b/.changeset/rare-pants-develop.md
@@ -0,0 +1,47 @@
+---
+'@graphql-mesh/fusion-runtime': minor
+'@graphql-tools/federation': minor
+'@graphql-hive/gateway-runtime': minor
+---
+
+Automatic Global Object Identification
+
+Setting the `globalObjectIdentification` option to true will automatically implement the
+GraphQL Global Object Identification Specification by adding a `Node` interface, `node(id: ID!): Node`
+and `nodes(ids: [ID!]!): [Node!]!` fields to the `Query` type.
+
+The `Node` interface will have a `nodeId` (not `id`!) field used as the global identifier. It
+is intentionally not `id` to avoid collisions with existing `id` fields in subgraphs.
+
+```graphql
+"""
+An object with a globally unique `ID`.
+"""
+interface Node {
+  """
+  A globally unique identifier. Can be used in various places throughout the system to identify this single value.
+  """
+  nodeId: ID!
+}
+
+extend type Query {
+  """
+  Fetches an object given its globally unique `ID`.
+  """
+  node(
+    """
+    The globally unique `ID`.
+    """
+    nodeId: ID!
+  ): Node
+  """
+  Fetches objects given their globally unique `ID`s.
+  """
+  nodes(
+    """
+    The globally unique `ID`s.
+    """
+    nodeIds: [ID!]!
+  ): [Node!]!
+}
+```

From 64f381761a95e50cd3b178bbd9df3a68a2e6da03 Mon Sep 17 00:00:00 2001
From: "github-actions[bot]" <github-actions[bot]@users.noreply.github.com>
Date: Thu, 12 Jun 2025 11:58:53 +0000
Subject: [PATCH 29/44] chore(dependencies): updated changesets for modified
 dependencies

---
 .changeset/@graphql-tools_federation-1232-dependencies.md | 8 ++++++++
 1 file changed, 8 insertions(+)
 create mode 100644 .changeset/@graphql-tools_federation-1232-dependencies.md

diff --git a/.changeset/@graphql-tools_federation-1232-dependencies.md b/.changeset/@graphql-tools_federation-1232-dependencies.md
new file mode 100644
index 000000000..5dceff497
--- /dev/null
+++ b/.changeset/@graphql-tools_federation-1232-dependencies.md
@@ -0,0 +1,8 @@
+---
+'@graphql-tools/federation': patch
+---
+
+dependencies updates: 
+
+- Added dependency [`@graphql-tools/batch-delegate@workspace:^` ↗︎](https://www.npmjs.com/package/@graphql-tools/batch-delegate/v/workspace:^) (to `dependencies`)
+- Added dependency [`graphql-relay@^0.10.2` ↗︎](https://www.npmjs.com/package/graphql-relay/v/0.10.2) (to `dependencies`)

From b35033b78fdcef5cd600346361bd3a389447297c Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Thu, 12 Jun 2025 14:36:50 +0200
Subject: [PATCH 30/44] resolve func

---
 .../src/globalObjectIdentification.ts         | 26 ++++++++++---------
 1 file changed, 14 insertions(+), 12 deletions(-)

diff --git a/packages/federation/src/globalObjectIdentification.ts b/packages/federation/src/globalObjectIdentification.ts
index 8b6d30d42..c32b73706 100644
--- a/packages/federation/src/globalObjectIdentification.ts
+++ b/packages/federation/src/globalObjectIdentification.ts
@@ -153,18 +153,20 @@ export function createResolvers({
       (resolvers, { typeName, keyFieldNames }) => ({
         ...resolvers,
         [typeName]: {
-          [nodeIdField](source) {
-            if (keyFieldNames.length === 1) {
-              // single field key
-              return toGlobalId(typeName, source[keyFieldNames[0]!]);
-            }
-            // multiple fields key
-            const keyFields: Record<string, unknown> = {};
-            for (const fieldName of keyFieldNames) {
-              // loop is faster than reduce
-              keyFields[fieldName] = source[fieldName];
-            }
-            return toGlobalId(typeName, JSON.stringify(keyFields));
+          [nodeIdField]: {
+            resolve(source) {
+              if (keyFieldNames.length === 1) {
+                // single field key
+                return toGlobalId(typeName, source[keyFieldNames[0]!]);
+              }
+              // multiple fields key
+              const keyFields: Record<string, unknown> = {};
+              for (const fieldName of keyFieldNames) {
+                // loop is faster than reduce
+                keyFields[fieldName] = source[fieldName];
+              }
+              return toGlobalId(typeName, JSON.stringify(keyFields));
+            },
           },
         },
       }),

From b5cbb77dda9dd265d855bec9eb3e347080f9c675 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Thu, 12 Jun 2025 14:37:34 +0200
Subject: [PATCH 31/44] node id without dependant fields

---
 .../src/globalObjectIdentification.ts         |  1 +
 .../tests/globalObjectIdentification.test.ts  | 71 +++++++++++++++++++
 2 files changed, 72 insertions(+)

diff --git a/packages/federation/src/globalObjectIdentification.ts b/packages/federation/src/globalObjectIdentification.ts
index c32b73706..108107900 100644
--- a/packages/federation/src/globalObjectIdentification.ts
+++ b/packages/federation/src/globalObjectIdentification.ts
@@ -154,6 +154,7 @@ export function createResolvers({
         ...resolvers,
         [typeName]: {
           [nodeIdField]: {
+            selectionSet: `{ ${keyFieldNames.join(' ')} }`,
             resolve(source) {
               if (keyFieldNames.length === 1) {
                 // single field key
diff --git a/packages/federation/tests/globalObjectIdentification.test.ts b/packages/federation/tests/globalObjectIdentification.test.ts
index 67588426a..125381bf1 100644
--- a/packages/federation/tests/globalObjectIdentification.test.ts
+++ b/packages/federation/tests/globalObjectIdentification.test.ts
@@ -219,6 +219,40 @@ describe('Global Object Identification', () => {
     `);
   });
 
+  it('should resolve node id without requesting key fields in client query', async () => {
+    const schema = await getStitchedSchemaFromLocalSchemas({
+      globalObjectIdentification: true,
+      localSchemas: {
+        accounts,
+      },
+    });
+
+    await expect(
+      Promise.resolve(
+        normalizedExecutor({
+          schema,
+          document: parse(/* GraphQL */ `
+            {
+              accounts {
+                nodeId
+              }
+            }
+          `),
+        }),
+      ),
+    ).resolves.toMatchInlineSnapshot(`
+      {
+        "data": {
+          "accounts": [
+            {
+              "nodeId": "QWNjb3VudDphMQ==",
+            },
+          ],
+        },
+      }
+    `);
+  });
+
   it('should not resolve single field key object from globally unique node when doesnt exist', async () => {
     const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,
@@ -292,6 +326,43 @@ describe('Global Object Identification', () => {
     `);
   });
 
+  it('should resolve node id without requesting key fields in client query', async () => {
+    const schema = await getStitchedSchemaFromLocalSchemas({
+      globalObjectIdentification: true,
+      localSchemas: {
+        people,
+      },
+    });
+
+    await expect(
+      Promise.resolve(
+        normalizedExecutor({
+          schema,
+          document: parse(/* GraphQL */ `
+            {
+              people {
+                nodeId
+              }
+            }
+          `),
+        }),
+      ),
+    ).resolves.toMatchInlineSnapshot(`
+      {
+        "data": {
+          "people": [
+            {
+              "nodeId": "UGVyc29uOnsiZmlyc3ROYW1lIjoiSm9obiIsImxhc3ROYW1lIjoiRG9lIn0=",
+            },
+            {
+              "nodeId": "UGVyc29uOnsiZmlyc3ROYW1lIjoiSmFuZSIsImxhc3ROYW1lIjoiRG9lIn0=",
+            },
+          ],
+        },
+      }
+    `);
+  });
+
   it('should resolve node id from object', async () => {
     const schema = await getStitchedSchemaFromLocalSchemas({
       globalObjectIdentification: true,

From 44f4a9ae6ba0cf06fe4c985c6b597e99ad1c2c3d Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Thu, 12 Jun 2025 14:40:23 +0200
Subject: [PATCH 32/44] add graphl

---
 e2e/global-object-identification/package.json | 1 +
 yarn.lock                                     | 1 +
 2 files changed, 2 insertions(+)

diff --git a/e2e/global-object-identification/package.json b/e2e/global-object-identification/package.json
index 686278497..15748fd9c 100644
--- a/e2e/global-object-identification/package.json
+++ b/e2e/global-object-identification/package.json
@@ -2,6 +2,7 @@
   "name": "@e2e/global-object-identification",
   "private": true,
   "dependencies": {
+    "graphql": "^16.11.0",
     "graphql-relay": "^0.10.2"
   }
 }
diff --git a/yarn.lock b/yarn.lock
index 70c38ad14..d5c4c422c 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3066,6 +3066,7 @@ __metadata:
   version: 0.0.0-use.local
   resolution: "@e2e/global-object-identification@workspace:e2e/global-object-identification"
   dependencies:
+    graphql: "npm:^16.11.0"
     graphql-relay: "npm:^0.10.2"
   languageName: unknown
   linkType: soft

From db46408d83f063eb88770bd004f35c7a76416718 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Thu, 12 Jun 2025 14:48:13 +0200
Subject: [PATCH 33/44] no generator

---
 .../src/globalObjectIdentification.ts         | 25 +++++++++++++------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/packages/federation/src/globalObjectIdentification.ts b/packages/federation/src/globalObjectIdentification.ts
index 108107900..e04131398 100644
--- a/packages/federation/src/globalObjectIdentification.ts
+++ b/packages/federation/src/globalObjectIdentification.ts
@@ -147,7 +147,7 @@ export function createResolvers({
   nodeIdField,
   subschemas,
 }: GlobalObjectIdentificationOptions): IResolvers {
-  const types = getDistinctResolvableTypes(subschemas).toArray();
+  const types = getDistinctResolvableTypes(subschemas);
   return {
     ...types.reduce(
       (resolvers, { typeName, keyFieldNames }) => ({
@@ -227,8 +227,18 @@ export function createResolvers({
   };
 }
 
-function* getDistinctResolvableTypes(subschemas: Iterable<SubschemaConfig>) {
-  const yieldedTypes = new Set<string>();
+interface DistinctResolvableType {
+  typeName: string;
+  subschema: SubschemaConfig;
+  merge: MergedTypeConfigFromEntities;
+  keyFieldNames: string[];
+}
+
+function getDistinctResolvableTypes(
+  subschemas: Iterable<SubschemaConfig>,
+): DistinctResolvableType[] {
+  const visitedTypeNames = new Set<string>();
+  const types: DistinctResolvableType[] = [];
   for (const subschema of subschemas) {
     // TODO: respect canonical types
     for (const [typeName, merge] of Object.entries(subschema.merge || {})
@@ -240,7 +250,7 @@ function* getDistinctResolvableTypes(subschemas: Iterable<SubschemaConfig>) {
         // sort by shortest keys first
         ([, a], [, b]) => a.selectionSet!.length - b.selectionSet!.length,
       )) {
-      if (yieldedTypes.has(typeName)) {
+      if (visitedTypeNames.has(typeName)) {
         // already yielded this type, all types can only have one resolution
         continue;
       }
@@ -272,13 +282,14 @@ function* getDistinctResolvableTypes(subschemas: Iterable<SubschemaConfig>) {
       }
       // what we're left in the "key" are simple field(s) like "id" or "email"
 
-      yieldedTypes.add(typeName);
-      yield {
+      visitedTypeNames.add(typeName);
+      types.push({
         typeName,
         subschema,
         merge: merge as MergedTypeConfigFromEntities,
         keyFieldNames: key.trim().split(/\s+/),
-      };
+      });
     }
   }
+  return types;
 }

From d8658039f275a2d55e85e8cf983b29eb9f8814c2 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Thu, 12 Jun 2025 15:28:39 +0200
Subject: [PATCH 34/44] properly merge resolvers

---
 packages/fusion-runtime/src/federation/supergraph.ts | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/packages/fusion-runtime/src/federation/supergraph.ts b/packages/fusion-runtime/src/federation/supergraph.ts
index c6698e184..448953685 100644
--- a/packages/fusion-runtime/src/federation/supergraph.ts
+++ b/packages/fusion-runtime/src/federation/supergraph.ts
@@ -10,7 +10,7 @@ import type {
   SubschemaConfig,
 } from '@graphql-tools/delegate';
 import { getStitchedSchemaFromSupergraphSdl } from '@graphql-tools/federation';
-import { mergeResolvers, mergeTypeDefs } from '@graphql-tools/merge';
+import { mergeTypeDefs } from '@graphql-tools/merge';
 import { createMergedTypeResolver } from '@graphql-tools/stitch';
 import { stitchingDirectives } from '@graphql-tools/stitching-directives';
 import {
@@ -212,7 +212,11 @@ export const handleFederationSupergraph: UnifiedGraphHandler = function ({
         additionalResolvers,
       );
       // @ts-expect-error - Typings are wrong
-      opts.resolvers = mergeResolvers(opts.resolvers, additionalResolvers);
+      opts.resolvers =
+        opts.resolvers && additionalResolvers
+          ? [opts.resolvers, ...additionalResolvers]
+          : additionalResolvers;
+      // opts.resolvers = additionalResolvers;
       // @ts-expect-error - Typings are wrong
       opts.inheritResolversFromInterfaces = true;
 

From bd7834d4aa93266d878c9766b3ad0c784e747f13 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Thu, 12 Jun 2025 15:42:31 +0200
Subject: [PATCH 35/44] simpler lol

---
 packages/fusion-runtime/src/federation/supergraph.ts | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/packages/fusion-runtime/src/federation/supergraph.ts b/packages/fusion-runtime/src/federation/supergraph.ts
index 448953685..35c42aeef 100644
--- a/packages/fusion-runtime/src/federation/supergraph.ts
+++ b/packages/fusion-runtime/src/federation/supergraph.ts
@@ -212,10 +212,9 @@ export const handleFederationSupergraph: UnifiedGraphHandler = function ({
         additionalResolvers,
       );
       // @ts-expect-error - Typings are wrong
-      opts.resolvers =
-        opts.resolvers && additionalResolvers
-          ? [opts.resolvers, ...additionalResolvers]
-          : additionalResolvers;
+      opts.resolvers = opts.resolvers
+        ? [opts.resolvers, ...additionalResolvers]
+        : additionalResolvers;
       // opts.resolvers = additionalResolvers;
       // @ts-expect-error - Typings are wrong
       opts.inheritResolversFromInterfaces = true;

From e7e9e644d114ebee38dfcd99d6af5b08ae8cef54 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Thu, 12 Jun 2025 18:06:46 +0200
Subject: [PATCH 36/44] improve tests

---
 .../tests/globalObjectIdentification.test.ts  | 631 +++++++++++-------
 1 file changed, 373 insertions(+), 258 deletions(-)

diff --git a/packages/federation/tests/globalObjectIdentification.test.ts b/packages/federation/tests/globalObjectIdentification.test.ts
index 125381bf1..cd7d99999 100644
--- a/packages/federation/tests/globalObjectIdentification.test.ts
+++ b/packages/federation/tests/globalObjectIdentification.test.ts
@@ -1,106 +1,14 @@
 import { buildSubgraphSchema } from '@apollo/subgraph';
 import { normalizedExecutor } from '@graphql-tools/executor';
 import { printSchemaWithDirectives } from '@graphql-tools/utils';
-import { parse } from 'graphql';
+import { parse, validate } from 'graphql';
 import { toGlobalId } from 'graphql-relay';
 import { describe, expect, it } from 'vitest';
 import { getStitchedSchemaFromLocalSchemas } from './getStitchedSchemaFromLocalSchemas';
 
 describe('Global Object Identification', () => {
-  const data = {
-    accounts: [
-      {
-        id: 'a1',
-        name: 'John Doe',
-        email: 'john@doe.com',
-      },
-    ],
-    auth: [
-      {
-        id: 'a1',
-        isVerified: true,
-      },
-    ],
-    people: [
-      {
-        firstName: 'John',
-        lastName: 'Doe',
-        email: 'john@doe.com',
-      },
-      {
-        firstName: 'Jane',
-        lastName: 'Doe',
-        email: 'jane@doe.com',
-      },
-    ],
-  };
-
-  const accounts = buildSubgraphSchema({
-    typeDefs: parse(/* GraphQL */ `
-      type Query {
-        accounts: [Account!]!
-      }
-      type Account @key(fields: "id") {
-        id: ID!
-        name: String!
-        email: String!
-      }
-    `),
-    resolvers: {
-      Query: {
-        accounts: () => data.accounts,
-      },
-      Account: {
-        __resolveReference: (ref) => data.accounts.find((a) => a.id === ref.id),
-      },
-    },
-  });
-
-  const auth = buildSubgraphSchema({
-    typeDefs: parse(/* GraphQL */ `
-      type Account @key(fields: "id") {
-        id: ID!
-        isVerified: Boolean!
-      }
-    `),
-    resolvers: {
-      Account: {
-        __resolveReference: (ref) => data.auth.find((a) => a.id === ref.id),
-      },
-    },
-  });
-
-  const people = buildSubgraphSchema({
-    typeDefs: parse(/* GraphQL */ `
-      type Query {
-        people: [Person!]!
-      }
-      type Person @key(fields: "firstName lastName") {
-        firstName: String!
-        lastName: String!
-        email: String!
-      }
-    `),
-    resolvers: {
-      Query: {
-        people: () => data.people,
-      },
-      Person: {
-        __resolveReference: (ref) =>
-          data.people.find(
-            (a) => a.firstName === ref.firstName && a.lastName === ref.lastName,
-          ),
-      },
-    },
-  });
-
   it('should generate stitched schema with node interface', async () => {
-    const schema = await getStitchedSchemaFromLocalSchemas({
-      globalObjectIdentification: true,
-      localSchemas: {
-        accounts,
-      },
-    });
+    const { schema } = await getSchema();
 
     expect(printSchemaWithDirectives(schema)).toMatchInlineSnapshot(`
       "schema {
@@ -108,7 +16,9 @@ describe('Global Object Identification', () => {
       }
 
       type Query {
-        accounts: [Account!]!
+        feed: [Story!]!
+        people: [Person!]!
+        organizations: [Organization!]!
         """Fetches an object given its globally unique \`ID\`."""
         node(
           """The globally unique \`ID\`."""
@@ -116,10 +26,36 @@ describe('Global Object Identification', () => {
         ): Node
       }
 
-      type Account implements Node {
+      interface Actor {
         id: ID!
         name: String!
-        email: String!
+      }
+
+      type Organization implements Actor & Node {
+        id: ID!
+        name: String!
+        foundingDate: String!
+        """
+        A globally unique identifier. Can be used in various places throughout the system to identify this single value.
+        """
+        nodeId: ID!
+      }
+
+      type Person implements Actor & Node {
+        id: ID!
+        name: String!
+        dateOfBirth: String!
+        """
+        A globally unique identifier. Can be used in various places throughout the system to identify this single value.
+        """
+        nodeId: ID!
+      }
+
+      type Story implements Node {
+        title: String!
+        publishedAt: String!
+        actor: Actor!
+        content: String!
         """
         A globally unique identifier. Can be used in various places throughout the system to identify this single value.
         """
@@ -136,39 +72,55 @@ describe('Global Object Identification', () => {
   });
 
   it('should resolve without node as usual', async () => {
-    const schema = await getStitchedSchemaFromLocalSchemas({
-      globalObjectIdentification: true,
-      localSchemas: {
-        accounts,
-        auth,
-      },
-    });
+    const { execute } = await getSchema();
 
     await expect(
-      Promise.resolve(
-        normalizedExecutor({
-          schema,
-          document: parse(/* GraphQL */ `
-            {
-              accounts {
-                id
+      execute({
+        query: /* GraphQL */ `
+          {
+            feed {
+              title
+              content
+              actor {
                 name
-                email
-                isVerified
+                ... on Person {
+                  dateOfBirth
+                }
+                ... on Organization {
+                  foundingDate
+                }
               }
             }
-          `),
-        }),
-      ),
+          }
+        `,
+      }),
     ).resolves.toMatchInlineSnapshot(`
       {
         "data": {
-          "accounts": [
+          "feed": [
             {
-              "email": "john@doe.com",
-              "id": "a1",
-              "isVerified": true,
-              "name": "John Doe",
+              "actor": {
+                "dateOfBirth": "2001-01-01",
+                "name": "John Doe",
+              },
+              "content": "Lorem ipsum dolor sit amet.",
+              "title": "Personal Story 1",
+            },
+            {
+              "actor": {
+                "dateOfBirth": "2002-02-02",
+                "name": "Jane Doe",
+              },
+              "content": "Lorem ipsum dolor sit amet.",
+              "title": "Personal Story 2",
+            },
+            {
+              "actor": {
+                "foundingDate": "1993-03-03",
+                "name": "Foo Inc.",
+              },
+              "content": "Lorem ipsum dolor sit amet.",
+              "title": "Corporate Story 3",
             },
           ],
         },
@@ -176,200 +128,161 @@ describe('Global Object Identification', () => {
     `);
   });
 
-  it('should resolve single field key object from globally unique node', async () => {
-    const schema = await getStitchedSchemaFromLocalSchemas({
-      globalObjectIdentification: true,
-      localSchemas: {
-        accounts,
-        auth,
-      },
-    });
+  it('should resolve single field key object', async () => {
+    const { data, execute } = await getSchema();
 
     await expect(
-      Promise.resolve(
-        normalizedExecutor({
-          schema,
-          document: parse(/* GraphQL */ `
+      execute({
+        query: /* GraphQL */ `
         {
-          node(nodeId: "${toGlobalId('Account', 'a1')}") {
+          node(nodeId: "${toGlobalId('Person', data.people[0].id)}") {
             nodeId
-            ... on Account {
-              id
+            ... on Person {
               name
-              email
-              isVerified
+              dateOfBirth
             }
           }
         }
-      `),
-        }),
-      ),
+      `,
+      }),
     ).resolves.toMatchInlineSnapshot(`
       {
         "data": {
           "node": {
-            "email": "john@doe.com",
-            "id": "a1",
-            "isVerified": true,
+            "dateOfBirth": "2001-01-01",
             "name": "John Doe",
-            "nodeId": "QWNjb3VudDphMQ==",
+            "nodeId": "UGVyc29uOnAx",
           },
         },
       }
     `);
   });
 
-  it('should resolve node id without requesting key fields in client query', async () => {
-    const schema = await getStitchedSchemaFromLocalSchemas({
-      globalObjectIdentification: true,
-      localSchemas: {
-        accounts,
-      },
-    });
+  it('should resolve multiple fields key object', async () => {
+    const { data, execute } = await getSchema();
 
     await expect(
-      Promise.resolve(
-        normalizedExecutor({
-          schema,
-          document: parse(/* GraphQL */ `
-            {
-              accounts {
-                nodeId
-              }
+      execute({
+        query: /* GraphQL */ `
+        {
+          node(nodeId: "${toGlobalId('Story', JSON.stringify(data.stories[1]))}") {
+            ... on Story {
+              nodeId
+              title
+              content
             }
-          `),
-        }),
-      ),
+          }
+        }
+      `,
+      }),
     ).resolves.toMatchInlineSnapshot(`
       {
         "data": {
-          "accounts": [
-            {
-              "nodeId": "QWNjb3VudDphMQ==",
-            },
-          ],
+          "node": {
+            "content": "Lorem ipsum dolor sit amet.",
+            "nodeId": "U3Rvcnk6eyJ0aXRsZSI6IlBlcnNvbmFsIFN0b3J5IDIiLCJwdWJsaXNoZWRBdCI6IjIwMTItMDItMDIifQ==",
+            "title": "Personal Story 2",
+          },
         },
       }
     `);
   });
 
-  it('should not resolve single field key object from globally unique node when doesnt exist', async () => {
-    const schema = await getStitchedSchemaFromLocalSchemas({
-      globalObjectIdentification: true,
-      localSchemas: {
-        accounts,
-      },
-    });
+  it('should resolve node id from object', async () => {
+    const { execute } = await getSchema();
 
     await expect(
-      Promise.resolve(
-        normalizedExecutor({
-          schema,
-          document: parse(/* GraphQL */ `
-        {
-          node(nodeId: "${toGlobalId('Account', 'dontexist1')}") {
-            nodeId
-            ... on Account {
-              id
+      execute({
+        query: /* GraphQL */ `
+          {
+            people {
+              nodeId # we omit the "id" key field making sure it's resolved internally
               name
-              email
+              dateOfBirth
             }
           }
-        }
-      `),
-        }),
-      ),
+        `,
+      }),
     ).resolves.toMatchInlineSnapshot(`
       {
         "data": {
-          "node": null,
+          "people": [
+            {
+              "dateOfBirth": "2001-01-01",
+              "name": "John Doe",
+              "nodeId": "UGVyc29uOnAx",
+            },
+            {
+              "dateOfBirth": "2002-02-02",
+              "name": "Jane Doe",
+              "nodeId": "UGVyc29uOnAy",
+            },
+          ],
         },
       }
     `);
-  });
-
-  it('should resolve multiple fields key object from globally unique node', async () => {
-    const schema = await getStitchedSchemaFromLocalSchemas({
-      globalObjectIdentification: true,
-      localSchemas: {
-        people,
-      },
-    });
 
     await expect(
-      Promise.resolve(
-        normalizedExecutor({
-          schema,
-          document: parse(/* GraphQL */ `
-        {
-          node(nodeId: "${toGlobalId('Person', JSON.stringify({ firstName: 'John', lastName: 'Doe' }))}") {
-            nodeId
-            ... on Person {
-              firstName
-              lastName
+      execute({
+        query: /* GraphQL */ `
+          {
+            feed {
+              nodeId # we omit the "title" and "publishedAt" key fields making sure it's resolved internally
             }
           }
-        }
-      `),
-        }),
-      ),
+        `,
+      }),
     ).resolves.toMatchInlineSnapshot(`
       {
         "data": {
-          "node": {
-            "firstName": "John",
-            "lastName": "Doe",
-            "nodeId": "UGVyc29uOnsiZmlyc3ROYW1lIjoiSm9obiIsImxhc3ROYW1lIjoiRG9lIn0=",
-          },
+          "feed": [
+            {
+              "nodeId": "U3Rvcnk6eyJ0aXRsZSI6IlBlcnNvbmFsIFN0b3J5IDEiLCJwdWJsaXNoZWRBdCI6IjIwMTEtMDEtMDEifQ==",
+            },
+            {
+              "nodeId": "U3Rvcnk6eyJ0aXRsZSI6IlBlcnNvbmFsIFN0b3J5IDIiLCJwdWJsaXNoZWRBdCI6IjIwMTItMDItMDIifQ==",
+            },
+            {
+              "nodeId": "U3Rvcnk6eyJ0aXRsZSI6IkNvcnBvcmF0ZSBTdG9yeSAzIiwicHVibGlzaGVkQXQiOiIyMDEzLTAzLTAzIn0=",
+            },
+          ],
         },
       }
     `);
   });
 
-  it('should resolve node id without requesting key fields in client query', async () => {
-    const schema = await getStitchedSchemaFromLocalSchemas({
-      globalObjectIdentification: true,
-      localSchemas: {
-        people,
-      },
-    });
+  it('should not resolve when object doesnt exist', async () => {
+    const { schema } = await getSchema();
 
     await expect(
       Promise.resolve(
         normalizedExecutor({
           schema,
           document: parse(/* GraphQL */ `
-            {
-              people {
-                nodeId
-              }
+        {
+          node(nodeId: "${toGlobalId('Person', 'IDontExist')}") {
+            ... on Person {
+              nodeId
+              id
+              name
+              dateOfBirth
             }
-          `),
+          }
+        }
+      `),
         }),
       ),
     ).resolves.toMatchInlineSnapshot(`
       {
         "data": {
-          "people": [
-            {
-              "nodeId": "UGVyc29uOnsiZmlyc3ROYW1lIjoiSm9obiIsImxhc3ROYW1lIjoiRG9lIn0=",
-            },
-            {
-              "nodeId": "UGVyc29uOnsiZmlyc3ROYW1lIjoiSmFuZSIsImxhc3ROYW1lIjoiRG9lIn0=",
-            },
-          ],
+          "node": null,
         },
       }
     `);
   });
 
-  it('should resolve node id from object', async () => {
-    const schema = await getStitchedSchemaFromLocalSchemas({
-      globalObjectIdentification: true,
-      localSchemas: {
-        accounts,
-      },
-    });
+  it('should not resolve when invalid node id', async () => {
+    const { schema } = await getSchema();
 
     await expect(
       Promise.resolve(
@@ -377,11 +290,13 @@ describe('Global Object Identification', () => {
           schema,
           document: parse(/* GraphQL */ `
             {
-              accounts {
-                nodeId
-                id
-                name
-                email
+              node(nodeId: "gibberish") {
+                ... on Organization {
+                  nodeId
+                  id
+                  name
+                  foundingDate
+                }
               }
             }
           `),
@@ -390,16 +305,216 @@ describe('Global Object Identification', () => {
     ).resolves.toMatchInlineSnapshot(`
       {
         "data": {
-          "accounts": [
-            {
-              "email": "john@doe.com",
-              "id": "a1",
-              "name": "John Doe",
-              "nodeId": "QWNjb3VudDphMQ==",
-            },
-          ],
+          "node": null,
         },
       }
     `);
   });
 });
+
+async function getSchema() {
+  const data = {
+    people: [
+      {
+        id: 'p1',
+        name: 'John Doe',
+        dateOfBirth: '2001-01-01',
+      },
+      {
+        id: 'p2',
+        name: 'Jane Doe',
+        dateOfBirth: '2002-02-02',
+      },
+    ] as const,
+    organizations: [
+      {
+        id: 'o3',
+        name: 'Foo Inc.',
+        foundingDate: '1993-03-03',
+      },
+      {
+        id: 'o4',
+        name: 'Bar Inc.',
+        foundingDate: '1994-04-04',
+      },
+    ] as const,
+    stories: [
+      {
+        title: 'Personal Story 1',
+        publishedAt: '2011-01-01',
+        content: 'Lorem ipsum dolor sit amet.',
+        actor: {
+          id: 'p1',
+        },
+      },
+      {
+        title: 'Personal Story 2',
+        publishedAt: '2012-02-02',
+        content: 'Lorem ipsum dolor sit amet.',
+        actor: {
+          id: 'p2',
+        },
+      },
+      {
+        title: 'Corporate Story 3',
+        publishedAt: '2013-03-03',
+        content: 'Lorem ipsum dolor sit amet.',
+        actor: {
+          id: 'o3',
+        },
+      },
+    ] as const,
+  };
+
+  const users = buildSubgraphSchema({
+    typeDefs: parse(/* GraphQL */ `
+      type Query {
+        people: [Person!]!
+        organizations: [Organization!]!
+      }
+
+      type Person @key(fields: "id") {
+        id: ID!
+        dateOfBirth: String!
+      }
+
+      type Organization @key(fields: "id") {
+        id: ID!
+        foundingDate: String!
+      }
+    `),
+    resolvers: {
+      Query: {
+        people: () =>
+          data.people.map((p) => ({
+            id: p.id,
+            dateOfBirth: p.dateOfBirth,
+          })),
+        organizations: () =>
+          data.organizations.map((o) => ({
+            id: o.id,
+            foundingDate: o.foundingDate,
+          })),
+      },
+      Person: {
+        __resolveReference: (ref) => {
+          const person = data.people.find((p) => p.id === ref.id);
+          return person
+            ? { id: person.id, dateOfBirth: person.dateOfBirth }
+            : null;
+        },
+      },
+      Organization: {
+        __resolveReference: (ref) => {
+          const org = data.organizations.find((o) => o.id === ref.id);
+          return org ? { id: org.id, foundingDate: org.foundingDate } : null;
+        },
+      },
+    },
+  });
+
+  const stories = buildSubgraphSchema({
+    typeDefs: parse(/* GraphQL */ `
+      type Query {
+        feed: [Story!]!
+      }
+
+      type Story @key(fields: "title publishedAt") {
+        title: String!
+        publishedAt: String!
+        actor: Actor!
+        content: String!
+      }
+
+      interface Actor @key(fields: "id") {
+        id: ID!
+        name: String!
+      }
+
+      type Person implements Actor @key(fields: "id") {
+        id: ID!
+        name: String!
+      }
+
+      type Organization implements Actor @key(fields: "id") {
+        id: ID!
+        name: String!
+      }
+    `),
+    resolvers: {
+      Query: {
+        feed: () => data.stories,
+      },
+      Actor: {
+        __resolveType: (ref) => {
+          if (data.people.find((p) => p.id === ref.id)) {
+            return 'Person';
+          }
+          if (data.organizations.find((o) => o.id === ref.id)) {
+            return 'Organization';
+          }
+          return null;
+        },
+      },
+      Person: {
+        __resolveReference(ref) {
+          const person = data.people.find((p) => p.id === ref.id);
+          return person ? { id: person.id, name: person.name } : null;
+        },
+        name(source) {
+          const person = data.people.find((p) => p.id === source.id);
+          return person ? person.name : null;
+        },
+      },
+      Organization: {
+        __resolveReference: (ref) => {
+          const org = data.organizations.find((o) => o.id === ref.id);
+          return org ? { id: org.id, name: org.name } : null;
+        },
+        name(source) {
+          const org = data.organizations.find((o) => o.id === source.id);
+          return org ? org.name : null;
+        },
+      },
+      Story: {
+        __resolveReference: (ref) =>
+          data.stories.find(
+            (s) => s.title === ref.title && s.publishedAt === ref.publishedAt,
+          ),
+      },
+    },
+  });
+
+  const schema = await getStitchedSchemaFromLocalSchemas({
+    globalObjectIdentification: true,
+    localSchemas: {
+      users,
+      stories,
+    },
+  });
+
+  return {
+    data,
+    schema,
+    async execute({
+      query,
+      variables,
+    }: {
+      query: string;
+      variables?: Record<string, unknown>;
+    }) {
+      const document = parse(query);
+      const errs = validate(schema, document);
+      if (errs.length === 1) {
+        throw errs[0];
+      } else if (errs.length) {
+        throw new AggregateError(errs, errs.map((e) => e.message).join('; '));
+      }
+      return normalizedExecutor({
+        schema,
+        document,
+        variableValues: variables,
+      });
+    },
+  };
+}

From 3ecd0fab73d6c6bde4e56f44974507d0b15ccb06 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Thu, 12 Jun 2025 18:11:03 +0200
Subject: [PATCH 37/44] interfaces should implement node too

---
 .../tests/globalObjectIdentification.test.ts  | 34 ++++++++++++++++++-
 1 file changed, 33 insertions(+), 1 deletion(-)

diff --git a/packages/federation/tests/globalObjectIdentification.test.ts b/packages/federation/tests/globalObjectIdentification.test.ts
index cd7d99999..6a3644b07 100644
--- a/packages/federation/tests/globalObjectIdentification.test.ts
+++ b/packages/federation/tests/globalObjectIdentification.test.ts
@@ -26,9 +26,13 @@ describe('Global Object Identification', () => {
         ): Node
       }
 
-      interface Actor {
+      interface Actor implements Node {
         id: ID!
         name: String!
+        """
+        A globally unique identifier. Can be used in various places throughout the system to identify this single value.
+        """
+        nodeId: ID!
       }
 
       type Organization implements Actor & Node {
@@ -158,6 +162,34 @@ describe('Global Object Identification', () => {
     `);
   });
 
+  it('should resolve single field key interface', async () => {
+    const { data, execute } = await getSchema();
+
+    await expect(
+      execute({
+        query: /* GraphQL */ `
+        {
+          node(nodeId: "${toGlobalId('Organization', data.organizations[0].id)}") {
+            ... on Actor {
+              nodeId
+              name
+            }
+          }
+        }
+      `,
+      }),
+    ).resolves.toMatchInlineSnapshot(`
+      {
+        "data": {
+          "node": {
+            "name": "Foo Inc.",
+            "nodeId": "T3JnYW5pemF0aW9uOm8z",
+          },
+        },
+      }
+    `);
+  });
+
   it('should resolve multiple fields key object', async () => {
     const { data, execute } = await getSchema();
 

From 96e0a18f2d0bf8db8f4d2b7137a25af7e40d856d Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Fri, 13 Jun 2025 18:12:53 +0200
Subject: [PATCH 38/44] improvements

---
 .../src/globalObjectIdentification.ts         | 149 ++++++++++--------
 packages/federation/src/supergraph.ts         |  37 +++--
 2 files changed, 113 insertions(+), 73 deletions(-)

diff --git a/packages/federation/src/globalObjectIdentification.ts b/packages/federation/src/globalObjectIdentification.ts
index e04131398..221616759 100644
--- a/packages/federation/src/globalObjectIdentification.ts
+++ b/packages/federation/src/globalObjectIdentification.ts
@@ -1,17 +1,19 @@
 import { batchDelegateToSchema } from '@graphql-tools/batch-delegate';
 import { StitchingInfo, SubschemaConfig } from '@graphql-tools/delegate';
-import { IResolvers } from '@graphql-tools/utils';
+import { IResolvers, parseSelectionSet } from '@graphql-tools/utils';
 import {
   DefinitionNode,
   FieldDefinitionNode,
   GraphQLList,
   GraphQLObjectType,
   InterfaceTypeDefinitionNode,
+  isObjectType,
   Kind,
   ObjectTypeExtensionNode,
+  SelectionSetNode,
 } from 'graphql';
 import { fromGlobalId, toGlobalId } from 'graphql-relay';
-import { MergedTypeConfigFromEntities } from './supergraph';
+import { isMergedEntityConfig, MergedEntityConfig } from './supergraph';
 
 export interface GlobalObjectIdentificationOptions {
   nodeIdField: string;
@@ -64,7 +66,7 @@ export function createNodeDefinitions({
 
   // extend type X implements Node
 
-  for (const { typeName } of getDistinctResolvableTypes(subschemas)) {
+  for (const { typeName } of getDistinctEntities(subschemas)) {
     const typeExtensionDef: ObjectTypeExtensionNode = {
       kind: Kind.OBJECT_TYPE_EXTENSION,
       name: {
@@ -147,14 +149,14 @@ export function createResolvers({
   nodeIdField,
   subschemas,
 }: GlobalObjectIdentificationOptions): IResolvers {
-  const types = getDistinctResolvableTypes(subschemas);
+  const types = getDistinctEntities(subschemas);
   return {
     ...types.reduce(
-      (resolvers, { typeName, keyFieldNames }) => ({
+      (resolvers, { typeName, merge, keyFieldNames }) => ({
         ...resolvers,
         [typeName]: {
           [nodeIdField]: {
-            selectionSet: `{ ${keyFieldNames.join(' ')} }`,
+            selectionSet: merge.selectionSet,
             resolve(source) {
               if (keyFieldNames.length === 1) {
                 // single field key
@@ -183,9 +185,7 @@ export function createResolvers({
         }
 
         // we must use otherwise different schema
-        const types = getDistinctResolvableTypes(
-          stitchingInfo.subschemaMap.values(),
-        );
+        const types = getDistinctEntities(stitchingInfo.subschemaMap.values());
 
         const { id: idOrFields, type: typeName } = fromGlobalId(nodeId);
         const type = types.find((t) => t.typeName === typeName);
@@ -211,85 +211,106 @@ export function createResolvers({
         }
 
         return batchDelegateToSchema({
-          ...type.merge,
-          info,
           context,
+          info,
           schema: type.subschema,
+          fieldName: type.merge.fieldName,
+          argsFromKeys: type.merge.argsFromKeys,
+          key: { ...keyFields, __typename: typeName }, // we already have all the necessary keys
           returnType: new GraphQLList(
             // wont ever be undefined, we ensured the subschema has the type above
             type.subschema.schema.getType(typeName) as GraphQLObjectType,
           ),
-          selectionSet: undefined, // selectionSet is not needed here
-          key: { ...keyFields, __typename: typeName }, // we already have all the necessary keys
+          dataLoaderOptions: type.merge.dataLoaderOptions,
         });
       },
     },
   };
 }
 
-interface DistinctResolvableType {
+interface DistinctEntity {
   typeName: string;
   subschema: SubschemaConfig;
-  merge: MergedTypeConfigFromEntities;
+  merge: MergedEntityConfig;
   keyFieldNames: string[];
 }
 
-function getDistinctResolvableTypes(
-  subschemas: Iterable<SubschemaConfig>,
-): DistinctResolvableType[] {
-  const visitedTypeNames = new Set<string>();
-  const types: DistinctResolvableType[] = [];
-  for (const subschema of subschemas) {
-    // TODO: respect canonical types
-    for (const [typeName, merge] of Object.entries(subschema.merge || {})
-      .filter(
-        // make sure selectionset is defined for the sort to work
-        ([, merge]) => merge.selectionSet,
+function getDistinctEntities(
+  subschemasIter: Iterable<SubschemaConfig>,
+): DistinctEntity[] {
+  const distinctEntities: DistinctEntity[] = [];
+
+  const subschemas = Array.from(subschemasIter);
+  const types = subschemas.flatMap((subschema) =>
+    Object.values(subschema.schema.getTypeMap()),
+  );
+
+  const objects = types.filter(isObjectType);
+  for (const obj of objects) {
+    if (
+      distinctEntities.find(
+        (distinctType) => distinctType.typeName === obj.name,
       )
-      .sort(
-        // sort by shortest keys first
-        ([, a], [, b]) => a.selectionSet!.length - b.selectionSet!.length,
-      )) {
-      if (visitedTypeNames.has(typeName)) {
-        // already yielded this type, all types can only have one resolution
+    ) {
+      // already added this type
+      continue;
+    }
+    let candidate: {
+      subschema: SubschemaConfig;
+      merge: MergedEntityConfig;
+    } | null = null;
+    for (const subschema of subschemas) {
+      const merge = subschema.merge?.[obj.name];
+      if (!merge) {
+        // not resolvable from this subschema
         continue;
       }
-
-      if (
-        !merge.selectionSet ||
-        !merge.argsFromKeys ||
-        !merge.key ||
-        !merge.fieldName ||
-        !merge.dataLoaderOptions
-      ) {
-        // cannot be resolved globally
+      if (!isMergedEntityConfig(merge)) {
+        // not a merged entity config, cannot be resolved globally
         continue;
       }
-
-      // remove first and last characters from the selection set making up the key (curly braces, `{ id } -> id`)
-      const key = merge.selectionSet.trim().slice(1, -1).trim();
-      if (
-        // the key for fetching this object contains other objects
-        key.includes('{') ||
-        // the key for fetching this object contains arguments
-        key.includes('(') ||
-        // the key contains aliases
-        key.includes(':')
-      ) {
-        // it's too complex to use global object identification
-        // TODO: do it anyways when need arises
+      if (merge.canonical) {
+        // this subschema is canonical (owner) for this type, no need to check other schemas
+        candidate = { subschema, merge };
+        break;
+      }
+      if (!candidate) {
+        // first merge candidate
+        candidate = { subschema, merge };
         continue;
       }
-      // what we're left in the "key" are simple field(s) like "id" or "email"
-
-      visitedTypeNames.add(typeName);
-      types.push({
-        typeName,
-        subschema,
-        merge: merge as MergedTypeConfigFromEntities,
-        keyFieldNames: key.trim().split(/\s+/),
-      });
+      if (merge.selectionSet.length < candidate.merge.selectionSet.length) {
+        // found a better candidate
+        candidate = { subschema, merge };
+      }
+    }
+    if (!candidate) {
+      // no merge candidate found, cannot be resolved globally
+      continue;
     }
+    // is an entity that can efficiently be resolved globally
+    distinctEntities.push({
+      ...candidate,
+      typeName: obj.name,
+      keyFieldNames: (function getRootFieldNames(
+        selectionSet: SelectionSetNode,
+      ): string[] {
+        const fieldNames: string[] = [];
+        for (const sel of selectionSet.selections) {
+          if (sel.kind === Kind.FRAGMENT_SPREAD) {
+            throw new Error('Fragment spreads cannot appear in @key fields');
+          }
+          if (sel.kind === Kind.INLINE_FRAGMENT) {
+            fieldNames.push(...getRootFieldNames(sel.selectionSet));
+            continue;
+          }
+          // Kind.FIELD
+          fieldNames.push(sel.alias?.value || sel.name.value);
+        }
+        return fieldNames;
+      })(parseSelectionSet(candidate.merge.selectionSet)),
+    });
   }
-  return types;
+
+  return distinctEntities;
 }
diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index faa16cd97..a8347c43a 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -871,9 +871,7 @@ export function getStitchingOptionsFromSupergraphSdl(
           mergedTypeConfig.canonical = true;
         }
 
-        function getMergedTypeConfigFromKey(
-          key: string,
-        ): MergedTypeConfigFromEntities {
+        function getMergedTypeConfigFromKey(key: string): MergedEntityConfig {
           return {
             selectionSet: `{ ${key} }`,
             argsFromKeys: getArgsFromKeysForFederation,
@@ -1748,9 +1746,30 @@ function mergeResults(results: unknown[], getFieldNames: () => Set<string>) {
   return null;
 }
 
-export type MergedTypeConfigFromEntities = Required<
-  Pick<
-    MergedTypeConfig,
-    'selectionSet' | 'argsFromKeys' | 'key' | 'fieldName' | 'dataLoaderOptions'
-  >
->;
+/**
+ * A merge type configuration for resolving types that are Apollo Federation entities.
+ * @see https://www.apollographql.com/docs/graphos/schema-design/federated-schemas/entities/intro
+ */
+export type MergedEntityConfig = MergedTypeConfig &
+  Required<
+    Pick<
+      MergedTypeConfig,
+      | 'selectionSet'
+      | 'argsFromKeys'
+      | 'key'
+      | 'fieldName'
+      | 'dataLoaderOptions'
+    >
+  >;
+
+export function isMergedEntityConfig(
+  merge: MergedTypeConfig,
+): merge is MergedEntityConfig {
+  return (
+    'selectionSet' in merge &&
+    'argsFromKeys' in merge &&
+    'key' in merge &&
+    'fieldName' in merge &&
+    'dataLoaderOptions' in merge
+  );
+}

From 68b99cb7ad78bf7b63d22349fa79c1a749751114 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 23 Jun 2025 18:24:17 +0200
Subject: [PATCH 39/44] interface support

---
 .../src/globalObjectIdentification.ts         | 103 ++++++++++++++----
 .../tests/globalObjectIdentification.test.ts  |  35 +++++-
 2 files changed, 113 insertions(+), 25 deletions(-)

diff --git a/packages/federation/src/globalObjectIdentification.ts b/packages/federation/src/globalObjectIdentification.ts
index 221616759..fb478549f 100644
--- a/packages/federation/src/globalObjectIdentification.ts
+++ b/packages/federation/src/globalObjectIdentification.ts
@@ -7,6 +7,8 @@ import {
   GraphQLList,
   GraphQLObjectType,
   InterfaceTypeDefinitionNode,
+  InterfaceTypeExtensionNode,
+  isInterfaceType,
   isObjectType,
   Kind,
   ObjectTypeExtensionNode,
@@ -66,9 +68,14 @@ export function createNodeDefinitions({
 
   // extend type X implements Node
 
-  for (const { typeName } of getDistinctEntities(subschemas)) {
-    const typeExtensionDef: ObjectTypeExtensionNode = {
-      kind: Kind.OBJECT_TYPE_EXTENSION,
+  for (const { typeName, kind } of getDistinctEntities(subschemas)) {
+    const typeExtensionDef:
+      | ObjectTypeExtensionNode
+      | InterfaceTypeExtensionNode = {
+      kind:
+        kind === 'object'
+          ? Kind.OBJECT_TYPE_EXTENSION
+          : Kind.INTERFACE_TYPE_EXTENSION,
       name: {
         kind: Kind.NAME,
         value: typeName,
@@ -149,7 +156,13 @@ export function createResolvers({
   nodeIdField,
   subschemas,
 }: GlobalObjectIdentificationOptions): IResolvers {
-  const types = getDistinctEntities(subschemas);
+  // we can safely skip interfaces here because the concrete type will be known
+  // when resolving and the type will always be an object
+  //
+  // the nodeIdField will ALWAYS be the global ID identifying the concrete object
+  const types = getDistinctEntities(subschemas).filter(
+    (t) => t.kind === 'object',
+  );
   return {
     ...types.reduce(
       (resolvers, { typeName, merge, keyFieldNames }) => ({
@@ -184,24 +197,28 @@ export function createResolvers({
           return null; // no stitching info, something went wrong // TODO: throw instead?
         }
 
-        // we must use otherwise different schema
-        const types = getDistinctEntities(stitchingInfo.subschemaMap.values());
+        // TODO: potential performance bottleneck, memoize
+        const entities = getDistinctEntities(
+          // the stitchingInfo.subschemaMap.values() is different from subschemas. it
+          // contains the actual source of truth with all resolvers prepared - use it
+          stitchingInfo.subschemaMap.values(),
+        ).filter((t) => t.kind === 'object');
 
         const { id: idOrFields, type: typeName } = fromGlobalId(nodeId);
-        const type = types.find((t) => t.typeName === typeName);
-        if (!type) {
-          return null; // unknown type
+        const entity = entities.find((t) => t.typeName === typeName);
+        if (!entity) {
+          return null; // unknown object type
         }
 
         const keyFields: Record<string, unknown> = {};
-        if (type.keyFieldNames.length === 1) {
+        if (entity.keyFieldNames.length === 1) {
           // single field key
-          keyFields[type.keyFieldNames[0]!] = idOrFields;
+          keyFields[entity.keyFieldNames[0]!] = idOrFields;
         } else {
           // multiple fields key
           try {
             const idFields = JSON.parse(idOrFields);
-            for (const fieldName of type.keyFieldNames) {
+            for (const fieldName of entity.keyFieldNames) {
               // loop is faster than reduce
               keyFields[fieldName] = idFields[fieldName];
             }
@@ -213,32 +230,45 @@ export function createResolvers({
         return batchDelegateToSchema({
           context,
           info,
-          schema: type.subschema,
-          fieldName: type.merge.fieldName,
-          argsFromKeys: type.merge.argsFromKeys,
+          schema: entity.subschema,
+          fieldName: entity.merge.fieldName,
+          argsFromKeys: entity.merge.argsFromKeys,
           key: { ...keyFields, __typename: typeName }, // we already have all the necessary keys
           returnType: new GraphQLList(
             // wont ever be undefined, we ensured the subschema has the type above
-            type.subschema.schema.getType(typeName) as GraphQLObjectType,
+            entity.subschema.schema.getType(typeName) as GraphQLObjectType,
           ),
-          dataLoaderOptions: type.merge.dataLoaderOptions,
+          dataLoaderOptions: entity.merge.dataLoaderOptions,
         });
       },
     },
   };
 }
 
-interface DistinctEntity {
+interface DistinctEntityInterface {
+  kind: 'interface';
+  typeName: string;
+}
+
+interface DistinctEntityObject {
+  kind: 'object';
   typeName: string;
   subschema: SubschemaConfig;
   merge: MergedEntityConfig;
   keyFieldNames: string[];
 }
 
+type DistinctEntity = DistinctEntityObject | DistinctEntityInterface;
+
 function getDistinctEntities(
   subschemasIter: Iterable<SubschemaConfig>,
 ): DistinctEntity[] {
   const distinctEntities: DistinctEntity[] = [];
+  function entityExists(typeName: string): boolean {
+    return distinctEntities.some(
+      (distinctType) => distinctType.typeName === typeName,
+    );
+  }
 
   const subschemas = Array.from(subschemasIter);
   const types = subschemas.flatMap((subschema) =>
@@ -247,11 +277,7 @@ function getDistinctEntities(
 
   const objects = types.filter(isObjectType);
   for (const obj of objects) {
-    if (
-      distinctEntities.find(
-        (distinctType) => distinctType.typeName === obj.name,
-      )
-    ) {
+    if (entityExists(obj.name)) {
       // already added this type
       continue;
     }
@@ -291,6 +317,7 @@ function getDistinctEntities(
     // is an entity that can efficiently be resolved globally
     distinctEntities.push({
       ...candidate,
+      kind: 'object',
       typeName: obj.name,
       keyFieldNames: (function getRootFieldNames(
         selectionSet: SelectionSetNode,
@@ -312,5 +339,35 @@ function getDistinctEntities(
     });
   }
 
+  // object entities must exist in order to support interfaces
+  if (distinctEntities.length) {
+    const interfaces = types.filter(isInterfaceType);
+    Interfaces: for (const inter of interfaces) {
+      if (entityExists(inter.name)) {
+        // already added this interface
+        continue;
+      }
+      // check if this interface is implemented exclusively by the entity objects
+      for (const subschema of subschemas) {
+        const impls = subschema.schema.getImplementations(inter);
+        if (impls.interfaces.length) {
+          // this interface is implemented by other interfaces, we wont be handling those atm
+          // TODO: handle interfaces that implement other interfaces
+          continue Interfaces;
+        }
+        if (!impls.objects.every(({ name }) => entityExists(name))) {
+          // implementing objects of this interface are not all distinct entities
+          // i.e. some implementing objects don't have the node id field
+          continue Interfaces;
+        }
+      }
+      // all subschemas entities implement exclusively this interface
+      distinctEntities.push({
+        kind: 'interface',
+        typeName: inter.name,
+      });
+    }
+  }
+
   return distinctEntities;
 }
diff --git a/packages/federation/tests/globalObjectIdentification.test.ts b/packages/federation/tests/globalObjectIdentification.test.ts
index 6a3644b07..cfaf93a6f 100644
--- a/packages/federation/tests/globalObjectIdentification.test.ts
+++ b/packages/federation/tests/globalObjectIdentification.test.ts
@@ -162,7 +162,7 @@ describe('Global Object Identification', () => {
     `);
   });
 
-  it('should resolve single field key interface', async () => {
+  it('should resolve single field key interface with implementing object node id', async () => {
     const { data, execute } = await getSchema();
 
     await expect(
@@ -171,7 +171,7 @@ describe('Global Object Identification', () => {
         {
           node(nodeId: "${toGlobalId('Organization', data.organizations[0].id)}") {
             ... on Actor {
-              nodeId
+              nodeId # even though on Actor, the nodeId will be the global ID of the implementing type
               name
             }
           }
@@ -190,6 +190,37 @@ describe('Global Object Identification', () => {
     `);
   });
 
+  it('should not resolve single field key interface with interface node id', async () => {
+    const { data, execute } = await getSchema();
+
+    await expect(
+      execute({
+        query: /* GraphQL */ `
+        {
+          node(nodeId: "${toGlobalId('Actor', data.organizations[0].id)}") {
+            ... on Actor {
+              nodeId
+              name
+            }
+          }
+        }
+      `,
+      }),
+    ).resolves.toMatchInlineSnapshot(`
+      {
+        "data": {
+          "node": null,
+        },
+      }
+    `);
+
+    // the node here will be always null because Actor is an interface and we cannot resolve it by id
+    // we can only resolve it by the implementing type id, which is Organization or Person in this case.
+    //
+    // we can also safely assume that the nodeId in an interface will never be generated a global ID for
+    // the interface itself - it will always be the global ID of the implementing type that got resolved
+  });
+
   it('should resolve multiple fields key object', async () => {
     const { data, execute } = await getSchema();
 

From ac30464e56a069f358ad110d207883345dc037ed Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 23 Jun 2025 18:57:29 +0200
Subject: [PATCH 40/44] configurable

---
 .../src/globalObjectIdentification.ts         | 25 +++++++-----
 packages/federation/src/index.ts              |  1 +
 packages/federation/src/supergraph.ts         | 39 +++++++++++--------
 .../getStitchedSchemaFromLocalSchemas.ts      |  3 +-
 .../fusion-runtime/src/unifiedGraphManager.ts |  9 +++--
 packages/runtime/src/types.ts                 |  8 ++--
 6 files changed, 50 insertions(+), 35 deletions(-)

diff --git a/packages/federation/src/globalObjectIdentification.ts b/packages/federation/src/globalObjectIdentification.ts
index fb478549f..f05419abc 100644
--- a/packages/federation/src/globalObjectIdentification.ts
+++ b/packages/federation/src/globalObjectIdentification.ts
@@ -18,14 +18,21 @@ import { fromGlobalId, toGlobalId } from 'graphql-relay';
 import { isMergedEntityConfig, MergedEntityConfig } from './supergraph';
 
 export interface GlobalObjectIdentificationOptions {
+  /**
+   * The field name of the global ID on the Node interface.
+   *
+   * The `Node` interface defaults to `nodeId`, not `id`! It is intentionally not
+   * `id` to avoid collisions with existing `id` fields in subgraphs.
+   *
+   * @default nodeId
+   */
   nodeIdField: string;
-  subschemas: SubschemaConfig[];
 }
 
-export function createNodeDefinitions({
-  nodeIdField,
-  subschemas,
-}: GlobalObjectIdentificationOptions) {
+export function createNodeDefinitions(
+  subschemas: SubschemaConfig[],
+  { nodeIdField }: GlobalObjectIdentificationOptions,
+) {
   const defs: DefinitionNode[] = [];
 
   // nodeId: ID
@@ -152,10 +159,10 @@ export function createNodeDefinitions({
   return defs;
 }
 
-export function createResolvers({
-  nodeIdField,
-  subschemas,
-}: GlobalObjectIdentificationOptions): IResolvers {
+export function createResolvers(
+  subschemas: SubschemaConfig[],
+  { nodeIdField }: GlobalObjectIdentificationOptions,
+): IResolvers {
   // we can safely skip interfaces here because the concrete type will be known
   // when resolving and the type will always be an object
   //
diff --git a/packages/federation/src/index.ts b/packages/federation/src/index.ts
index 3192f9209..e8aae385e 100644
--- a/packages/federation/src/index.ts
+++ b/packages/federation/src/index.ts
@@ -1,3 +1,4 @@
 export * from './managed-federation.js';
 export * from './supergraph.js';
+export * from './globalObjectIdentification.js';
 export * from './utils.js';
diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index a8347c43a..3605a7e73 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -70,6 +70,7 @@ import {
 import {
   createNodeDefinitions,
   createResolvers,
+  GlobalObjectIdentificationOptions,
 } from './globalObjectIdentification.js';
 import {
   filterInternalFieldsAndTypes,
@@ -135,10 +136,7 @@ export interface GetStitchingOptionsFromSupergraphSdlOpts {
   batchDelegateOptions?: MergedTypeConfig['dataLoaderOptions'];
   /**
    * Add support for GraphQL Global Object Identification Specification  by adding a `Node`
-   * interface, `node(id: ID!): Node` and `nodes(ids: [ID!]!): [Node!]!` fields to the `Query` type.
-   *
-   * The `Node` interface will have a `nodeId` (not `id`!) field used as the global identifier. It
-   * is intentionally not `id` to avoid collisions with existing `id` fields in subgraphs.
+   * interface, `node(nodeId: ID!): Node` and `nodes(nodeIds: [ID!]!): [Node!]!` fields to the `Query` type.
    *
    * ```graphql
    * """An object with a globally unique `ID`."""
@@ -165,7 +163,7 @@ export interface GetStitchingOptionsFromSupergraphSdlOpts {
    *
    * @see https://graphql.org/learn/global-object-identification/
    */
-  globalObjectIdentification?: boolean;
+  globalObjectIdentification?: boolean | GlobalObjectIdentificationOptions;
 }
 
 export function getStitchingOptionsFromSupergraphSdl(
@@ -1548,30 +1546,37 @@ export function getStitchingOptionsFromSupergraphSdl(
       opts.onSubschemaConfig(subschema as FederationSubschemaConfig);
     }
   }
-  const shouldGlobalObjectIdent =
-    opts.globalObjectIdentification && typeNameKeysBySubgraphMap.size;
+  const globalObjectIdentification: GlobalObjectIdentificationOptions | null =
+    opts.globalObjectIdentification === true
+      ? // defaults
+        {
+          nodeIdField: 'nodeId',
+        }
+      : typeof opts.globalObjectIdentification === 'object'
+        ? // user configuration
+          opts.globalObjectIdentification
+        : null;
+  if (globalObjectIdentification && !typeNameKeysBySubgraphMap.size) {
+    throw new Error(
+      'Automatic Global Object Identification is enabled, but no subgraphs have entities defined with defined keys. Please ensure that at least one subgraph has a type with the `@key` directive making it an entity.',
+    );
+  }
   return {
     subschemas,
     typeDefs: {
       kind: Kind.DOCUMENT,
-      definitions: !shouldGlobalObjectIdent
+      definitions: !globalObjectIdentification
         ? extraDefinitions
         : [
             ...extraDefinitions,
-            ...createNodeDefinitions({
-              nodeIdField: 'nodeId',
-              subschemas,
-            }),
+            ...createNodeDefinitions(subschemas, globalObjectIdentification),
           ],
     } as DocumentNode,
     assumeValid: true,
     assumeValidSDL: true,
-    resolvers: !shouldGlobalObjectIdent
+    resolvers: !globalObjectIdentification
       ? undefined
-      : createResolvers({
-          nodeIdField: 'nodeId',
-          subschemas,
-        }),
+      : createResolvers(subschemas, globalObjectIdentification),
     typeMergingOptions: {
       useNonNullableFieldOnConflict: true,
       validationSettings: {
diff --git a/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts b/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
index 8f39045d4..dad4e2f30 100644
--- a/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
+++ b/packages/federation/tests/getStitchedSchemaFromLocalSchemas.ts
@@ -9,6 +9,7 @@ import { composeServices } from '@theguild/federation-composition';
 import { handleMaybePromise } from '@whatwg-node/promise-helpers';
 import { GraphQLSchema } from 'graphql';
 import { kebabCase } from 'lodash';
+import { GlobalObjectIdentificationOptions } from '../src/globalObjectIdentification';
 import { getStitchedSchemaFromSupergraphSdl } from '../src/supergraph';
 
 export interface LocalSchemaItem {
@@ -31,7 +32,7 @@ export async function getStitchedSchemaFromLocalSchemas({
   ) => void;
   composeWith?: 'apollo' | 'guild';
   ignoreRules?: string[];
-  globalObjectIdentification?: boolean;
+  globalObjectIdentification?: boolean | GlobalObjectIdentificationOptions;
 }): Promise<GraphQLSchema> {
   let supergraphSdl: string;
   if (composeWith === 'apollo') {
diff --git a/packages/fusion-runtime/src/unifiedGraphManager.ts b/packages/fusion-runtime/src/unifiedGraphManager.ts
index 9e31c3f60..7a8e53de2 100644
--- a/packages/fusion-runtime/src/unifiedGraphManager.ts
+++ b/packages/fusion-runtime/src/unifiedGraphManager.ts
@@ -5,6 +5,7 @@ import type {
 import type { Logger, OnDelegateHook } from '@graphql-mesh/types';
 import { dispose, isDisposable } from '@graphql-mesh/utils';
 import { CRITICAL_ERROR } from '@graphql-tools/executor';
+import type { GlobalObjectIdentificationOptions } from '@graphql-tools/federation';
 import type {
   ExecutionRequest,
   Executor,
@@ -68,7 +69,7 @@ export interface UnifiedGraphHandlerOpts {
   onDelegationPlanHooks?: OnDelegationPlanHook<any>[];
   onDelegationStageExecuteHooks?: OnDelegationStageExecuteHook<any>[];
   onDelegateHooks?: OnDelegateHook<unknown>[];
-  globalObjectIdentification?: boolean;
+  globalObjectIdentification?: boolean | GlobalObjectIdentificationOptions;
 
   logger?: Logger;
 }
@@ -109,7 +110,7 @@ export interface UnifiedGraphManagerOptions<TContext> {
 
   onUnifiedGraphChange?(newUnifiedGraph: GraphQLSchema): void;
 
-  globalObjectIdentification?: boolean;
+  globalObjectIdentification?: boolean | GlobalObjectIdentificationOptions;
 }
 
 export type Instrumentation = {
@@ -140,7 +141,9 @@ export class UnifiedGraphManager<TContext> implements AsyncDisposable {
   private lastLoadTime?: number;
   private executor?: Executor;
   private instrumentation: () => Instrumentation | undefined;
-  private globalObjectIdentification: boolean;
+  private globalObjectIdentification:
+    | boolean
+    | GlobalObjectIdentificationOptions;
 
   constructor(private opts: UnifiedGraphManagerOptions<TContext>) {
     this.batch = opts.batch ?? true;
diff --git a/packages/runtime/src/types.ts b/packages/runtime/src/types.ts
index 3f9d40fc7..0e4ac70d8 100644
--- a/packages/runtime/src/types.ts
+++ b/packages/runtime/src/types.ts
@@ -17,6 +17,7 @@ import type {
 } from '@graphql-mesh/types';
 import type { FetchInstrumentation, LogLevel } from '@graphql-mesh/utils';
 import type { HTTPExecutorOptions } from '@graphql-tools/executor-http';
+import type { GlobalObjectIdentificationOptions } from '@graphql-tools/federation';
 import type {
   IResolvers,
   MaybePromise,
@@ -195,10 +196,7 @@ export interface GatewayConfigSupergraph<
   pollingInterval?: number;
   /**
    * Add support for GraphQL Global Object Identification Specification  by adding a `Node`
-   * interface, `node(id: ID!): Node` and `nodes(ids: [ID!]!): [Node!]!` fields to the `Query` type.
-   *
-   * The `Node` interface will have a `nodeId` (not `id`!) field used as the global identifier. It
-   * is intentionally not `id` to avoid collisions with existing `id` fields in subgraphs.
+   * interface, `node(nodeId: ID!): Node` and `nodes(nodeIds: [ID!]!): [Node!]!` fields to the `Query` type.
    *
    * ```graphql
    * """An object with a globally unique `ID`."""
@@ -225,7 +223,7 @@ export interface GatewayConfigSupergraph<
    *
    * @see https://graphql.org/learn/global-object-identification/
    */
-  globalObjectIdentification?: boolean;
+  globalObjectIdentification?: boolean | GlobalObjectIdentificationOptions;
 }
 
 export interface GatewayConfigSubgraph<

From 156195254c55d95e225893056bb1fd08be2e6a62 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 23 Jun 2025 19:14:29 +0200
Subject: [PATCH 41/44] nodeidfield in args

---
 packages/federation/src/globalObjectIdentification.ts | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/packages/federation/src/globalObjectIdentification.ts b/packages/federation/src/globalObjectIdentification.ts
index f05419abc..8dc675cf4 100644
--- a/packages/federation/src/globalObjectIdentification.ts
+++ b/packages/federation/src/globalObjectIdentification.ts
@@ -196,7 +196,7 @@ export function createResolvers(
       {} as Record<string, IResolvers>,
     ),
     Query: {
-      node(_source, { nodeId }, context, info) {
+      node(_source, args, context, info) {
         const stitchingInfo = info.schema.extensions?.['stitchingInfo'] as
           | StitchingInfo
           | undefined;
@@ -211,7 +211,9 @@ export function createResolvers(
           stitchingInfo.subschemaMap.values(),
         ).filter((t) => t.kind === 'object');
 
-        const { id: idOrFields, type: typeName } = fromGlobalId(nodeId);
+        const { id: idOrFields, type: typeName } = fromGlobalId(
+          args[nodeIdField],
+        );
         const entity = entities.find((t) => t.typeName === typeName);
         if (!entity) {
           return null; // unknown object type

From 1cf5266edc5bb71dcfd6c1cfbdd6e13c2af0d75f Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 23 Jun 2025 19:17:56 +0200
Subject: [PATCH 42/44] no Query.nodes for now

---
 .changeset/rare-pants-develop.md      | 12 +-----------
 packages/federation/src/supergraph.ts |  9 ++-------
 packages/runtime/src/types.ts         |  9 ++-------
 3 files changed, 5 insertions(+), 25 deletions(-)

diff --git a/.changeset/rare-pants-develop.md b/.changeset/rare-pants-develop.md
index 24ffba25b..03a707a81 100644
--- a/.changeset/rare-pants-develop.md
+++ b/.changeset/rare-pants-develop.md
@@ -7,8 +7,7 @@
 Automatic Global Object Identification
 
 Setting the `globalObjectIdentification` option to true will automatically implement the
-GraphQL Global Object Identification Specification by adding a `Node` interface, `node(id: ID!): Node`
-and `nodes(ids: [ID!]!): [Node!]!` fields to the `Query` type.
+GraphQL Global Object Identification Specification by adding a `Node` interface and `node(id: ID!): Node` field to the `Query` type.
 
 The `Node` interface will have a `nodeId` (not `id`!) field used as the global identifier. It
 is intentionally not `id` to avoid collisions with existing `id` fields in subgraphs.
@@ -34,14 +33,5 @@ extend type Query {
     """
     nodeId: ID!
   ): Node
-  """
-  Fetches objects given their globally unique `ID`s.
-  """
-  nodes(
-    """
-    The globally unique `ID`s.
-    """
-    nodeIds: [ID!]!
-  ): [Node!]!
 }
 ```
diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index 3605a7e73..dd503e189 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -135,8 +135,8 @@ export interface GetStitchingOptionsFromSupergraphSdlOpts {
    */
   batchDelegateOptions?: MergedTypeConfig['dataLoaderOptions'];
   /**
-   * Add support for GraphQL Global Object Identification Specification  by adding a `Node`
-   * interface, `node(nodeId: ID!): Node` and `nodes(nodeIds: [ID!]!): [Node!]!` fields to the `Query` type.
+   * Add support for GraphQL Global Object Identification Specification by adding a `Node`
+   * interface and `node(nodeId: ID!): Node` field to the `Query` type.
    *
    * ```graphql
    * """An object with a globally unique `ID`."""
@@ -153,11 +153,6 @@ export interface GetStitchingOptionsFromSupergraphSdlOpts {
    *     """The globally unique `ID`."""
    *     nodeId: ID!
    *   ): Node
-   *   """Fetches objects given their globally unique `ID`s."""
-   *   nodes(
-   *     """The globally unique `ID`s."""
-   *     nodeIds: [ID!]!
-   *   ): [Node!]!
    * }
    * ```
    *
diff --git a/packages/runtime/src/types.ts b/packages/runtime/src/types.ts
index 0e4ac70d8..73493c219 100644
--- a/packages/runtime/src/types.ts
+++ b/packages/runtime/src/types.ts
@@ -195,8 +195,8 @@ export interface GatewayConfigSupergraph<
    */
   pollingInterval?: number;
   /**
-   * Add support for GraphQL Global Object Identification Specification  by adding a `Node`
-   * interface, `node(nodeId: ID!): Node` and `nodes(nodeIds: [ID!]!): [Node!]!` fields to the `Query` type.
+   * Add support for GraphQL Global Object Identification Specification by adding a `Node`
+   * interface and `node(nodeId: ID!): Node` field to the `Query` type.
    *
    * ```graphql
    * """An object with a globally unique `ID`."""
@@ -213,11 +213,6 @@ export interface GatewayConfigSupergraph<
    *     """The globally unique `ID`."""
    *     nodeId: ID!
    *   ): Node
-   *   """Fetches objects given their globally unique `ID`s."""
-   *   nodes(
-   *     """The globally unique `ID`s."""
-   *     nodeIds: [ID!]!
-   *   ): [Node!]!
    * }
    * ```
    *

From 2d32ff63f92d606ce9f49729627fa5bafed84067 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 23 Jun 2025 19:27:57 +0200
Subject: [PATCH 43/44] configurable from/to id

---
 .../src/globalObjectIdentification.ts         | 36 ++++++++++++++++---
 packages/federation/src/supergraph.ts         |  4 +--
 2 files changed, 33 insertions(+), 7 deletions(-)

diff --git a/packages/federation/src/globalObjectIdentification.ts b/packages/federation/src/globalObjectIdentification.ts
index 8dc675cf4..3aee79098 100644
--- a/packages/federation/src/globalObjectIdentification.ts
+++ b/packages/federation/src/globalObjectIdentification.ts
@@ -14,9 +14,16 @@ import {
   ObjectTypeExtensionNode,
   SelectionSetNode,
 } from 'graphql';
-import { fromGlobalId, toGlobalId } from 'graphql-relay';
+import * as graphqlRelay from 'graphql-relay';
 import { isMergedEntityConfig, MergedEntityConfig } from './supergraph';
 
+export interface ResolvedGlobalId {
+  /** The concrete type of the globally identifiable node. */
+  type: string;
+  /** The actual ID of the concrete type in the relevant source. */
+  id: string;
+}
+
 export interface GlobalObjectIdentificationOptions {
   /**
    * The field name of the global ID on the Node interface.
@@ -26,12 +33,29 @@ export interface GlobalObjectIdentificationOptions {
    *
    * @default nodeId
    */
-  nodeIdField: string;
+  nodeIdField?: string;
+  /**
+   * Takes a type name and an ID specific to that type name, and returns a
+   * "global ID" that is unique among all types.
+   *
+   * Note that the global ID can contain a JSON stringified object which
+   * contains multiple key fields needed to identify the object.
+   *
+   * @default import('graphql-relay').toGlobalId
+   */
+  toGlobalId?(type: string, id: string | number): string;
+  /**
+   * Takes the "global ID" created by toGlobalID, and returns the type name and ID
+   * used to create it.
+   *
+   * @default import('graphql-relay').fromGlobalId
+   */
+  fromGlobalId?(globalId: string): ResolvedGlobalId;
 }
 
 export function createNodeDefinitions(
   subschemas: SubschemaConfig[],
-  { nodeIdField }: GlobalObjectIdentificationOptions,
+  { nodeIdField = 'nodeId' }: GlobalObjectIdentificationOptions,
 ) {
   const defs: DefinitionNode[] = [];
 
@@ -161,7 +185,11 @@ export function createNodeDefinitions(
 
 export function createResolvers(
   subschemas: SubschemaConfig[],
-  { nodeIdField }: GlobalObjectIdentificationOptions,
+  {
+    nodeIdField = 'nodeId',
+    fromGlobalId = graphqlRelay.fromGlobalId,
+    toGlobalId = graphqlRelay.toGlobalId,
+  }: GlobalObjectIdentificationOptions,
 ): IResolvers {
   // we can safely skip interfaces here because the concrete type will be known
   // when resolving and the type will always be an object
diff --git a/packages/federation/src/supergraph.ts b/packages/federation/src/supergraph.ts
index dd503e189..812937819 100644
--- a/packages/federation/src/supergraph.ts
+++ b/packages/federation/src/supergraph.ts
@@ -1544,9 +1544,7 @@ export function getStitchingOptionsFromSupergraphSdl(
   const globalObjectIdentification: GlobalObjectIdentificationOptions | null =
     opts.globalObjectIdentification === true
       ? // defaults
-        {
-          nodeIdField: 'nodeId',
-        }
+        {}
       : typeof opts.globalObjectIdentification === 'object'
         ? // user configuration
           opts.globalObjectIdentification

From 528b9ad3ecc81ee9fc6444ab0046799f44e1cd10 Mon Sep 17 00:00:00 2001
From: Denis Badurina <denis@denelop.com>
Date: Mon, 23 Jun 2025 19:35:11 +0200
Subject: [PATCH 44/44] no node collision

---
 packages/federation/src/globalObjectIdentification.ts | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/packages/federation/src/globalObjectIdentification.ts b/packages/federation/src/globalObjectIdentification.ts
index 3aee79098..04ff4d96f 100644
--- a/packages/federation/src/globalObjectIdentification.ts
+++ b/packages/federation/src/globalObjectIdentification.ts
@@ -312,6 +312,17 @@ function getDistinctEntities(
     Object.values(subschema.schema.getTypeMap()),
   );
 
+  for (const type of types) {
+    if (type.name === 'Node') {
+      throw new Error(
+        `The "Node" interface is reserved for Automatic Global Object Identification and should not be defined in subgraphs. Interface is found in the following subgraphs: ${subschemas
+          .filter((s) => s.schema.getType('Node'))
+          .map((s) => `"${s.name!}"`)
+          .join(', ')}`,
+      );
+    }
+  }
+
   const objects = types.filter(isObjectType);
   for (const obj of objects) {
     if (entityExists(obj.name)) {