Switch from eslint to biome

.editorconfig

@@ -4,7 +4,8 @@ root = true
 charset=utf-8
 end_of_line = lf
 
-[*.{ts,tsx,css}]
+[*.{ts,tsx,cts,mts,js,cjs,mjs,css,json,graphql}]
+indent_style = space
 indent_size = 2
 insert_final_newline = true
 trim_trailing_whitespace = true

.github/dependabot.yml

@@ -55,12 +55,6 @@ updates:
       - "Z-Deps-Frontend"
     schedule:
       interval: "daily"
-    ignore:
-      # We don't want to migrate to eslint 9 for now
-      - dependency-name: "eslint"
-        update-types: ["version-update:semver-major"]
-      - dependency-name: "eslint-*"
-        update-types: ["version-update:semver-major"]
     groups:
       storybook:
         patterns:
@@ -94,10 +88,6 @@ updates:
         patterns:
           - "jotai"
           - "jotai-*"
-      eslint:
-        patterns:
-          - "eslint"
-          - "eslint-*"
       urql:
         patterns:
           - "urql"
@@ -127,11 +117,6 @@ updates:
       # Ignore @types/node until we can upgrade to Node 20
       - dependency-name: "@types/node"
         update-types: ["version-update:semver-major"]
-      # We don't want to migrate to eslint 9 for now
-      - dependency-name: "eslint"
-        update-types: ["version-update:semver-major"]
-      - dependency-name: "eslint-*"
-        update-types: ["version-update:semver-major"]
     groups:
       production:
         dependency-type: "production"

biome.json

@@ -0,0 +1,35 @@
+{
+  "$schema": "https://biomejs.dev/schemas/1.9.4/schema.json",
+  "organizeImports": {
+    "enabled": true
+  },
+  "vcs": {
+    "enabled": true,
+    "clientKind": "git",
+    "useIgnoreFile": true
+  },
+  "files": {
+    "ignore": [
+      ".devcontainer/**",
+      "docs/**",
+      "translations/**",
+      "policies/**",
+      "crates/**",
+      "frontend/src/gql/**",
+      "frontend/src/routeTree.gen.ts",
+      "**/coverage/**",
+      "**/dist/**"
+    ]
+  },
+  "formatter": {
+    "enabled": true,
+    "useEditorconfig": true,
+    "ignore": ["frontend/.storybook/locales.ts", "frontend/locales/*.json"]
+  },
+  "linter": {
+    "enabled": true,
+    "rules": {
+      "recommended": true
+    }
+  }
+}

frontend/.editorconfig

@@ -0,0 +1,11 @@
+root = true
+
+[*]
+charset=utf-8
+end_of_line = lf
+
+[*.{ts,tsx,js,cjs,mjs,css,json,graphql}]
+indent_style = space
+indent_size = 2
+insert_final_newline = true
+trim_trailing_whitespace = true

frontend/.storybook/preview.tsx

@@ -4,15 +4,20 @@
 // SPDX-License-Identifier: AGPL-3.0-only
 // Please see LICENSE in the repository root for full details.
 
-import { ArgTypes, Decorator, Parameters, Preview } from "@storybook/react";
-import { useLayoutEffect } from "react";
+import type {
+  ArgTypes,
+  Decorator,
+  Parameters,
+  Preview,
+} from "@storybook/react";
 import { TooltipProvider } from "@vector-im/compound-web";
+import { useLayoutEffect } from "react";
 
 import "../src/shared.css";
 import i18n from "../src/i18n";
 
-import localazyMetadata from "./locales";
 import { DummyRouter } from "../src/test-utils/router";
+import localazyMetadata from "./locales";
 
 export const parameters: Parameters = {
   controls: {

frontend/codegen.ts

@@ -4,14 +4,7 @@
 // SPDX-License-Identifier: AGPL-3.0-only
 // Please see LICENSE in the repository root for full details.
 
-import { CodegenConfig } from "@graphql-codegen/cli";
-
-// Adds a comment to the top of generated files to ignore linting and formatting
-const lintIgnore = {
-  add: {
-    content: "/* prettier-ignore */\n/* eslint-disable */",
-  },
-} as const;
+import type { CodegenConfig } from "@graphql-codegen/cli";
 
 const config: CodegenConfig = {
   schema: "./schema.graphql",
@@ -21,17 +14,14 @@ const config: CodegenConfig = {
     "./src/gql/": {
       preset: "client",
       config: {
+        useTypeImports: true,
         // By default, unknown scalars are generated as `any`. This is not ideal for catching potential bugs.
         defaultScalarType: "unknown",
         scalars: {
           DateTime: "string",
           Url: "string",
         },
       },
-      plugins: [lintIgnore],
-    },
-    "./src/gql/schema.ts": {
-      plugins: ["urql-introspection", lintIgnore],
     },
   },
 };