diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a03b48bfd..e009a7ecc 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -322,3 +322,5 @@ jobs:
     secrets:
       ALGOLIA_API_KEY: ${{ secrets.ALGOLIA_API_KEY }}
       VERCEL_TOKEN: ${{ secrets.VERCEL_TOKEN }}
+      VERCEL_ORG_ID: ${{ secrets.VERCEL_ORG_ID }}
+      VERCEL_PROJECT_ID: ${{ secrets.VERCEL_PROJECT_ID }}
diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index c0e7f23e4..a80bd4d73 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -15,7 +15,12 @@ on:
       VERCEL_TOKEN:
         required: false
         description: The Vercel token. Required if 'publish_target' is set.
-
+      VERCEL_ORG_ID:
+        required: false
+        description: The Vercel token. Required if 'publish_target' is set.
+      VERCEL_PROJECT_ID:
+        required: false
+        description: The Vercel token. Required if 'publish_target' is set.
 env:
   GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
@@ -62,10 +67,11 @@ jobs:
 
       - name: Publish docs
         if: ${{ inputs.publish_target }}
+        env:
+          VERCEL_ORG_ID: ${{ secrets.VERCEL_ORG_ID }}
+          VERCEL_PROJECT_ID: ${{ secrets.VERCEL_PROJECT_ID }}
         run: |
           npx vercel deploy packages/docs/build \
             -t '${{ secrets.VERCEL_TOKEN }}' \
-            --name typescript \
-            --scope temporal \
             --yes \
             ${{ inputs.publish_target == 'prod' && '--prod' || '' }}
diff --git a/packages/common/src/internal-non-workflow/codec-types.ts b/packages/common/src/internal-non-workflow/codec-types.ts
index 1e866c480..3fe4d6313 100644
--- a/packages/common/src/internal-non-workflow/codec-types.ts
+++ b/packages/common/src/internal-non-workflow/codec-types.ts
@@ -23,12 +23,14 @@ export type ReplaceNested<T, ToReplace, ReplaceWith> = T extends (...args: any[]
   ? T
   : [keyof T] extends [never]
     ? T
-    : T extends { [k: string]: ToReplace }
-      ? {
-          [P in keyof T]: ReplaceNested<T[P], ToReplace, ReplaceWith>;
-        }
-      : T extends ToReplace
-        ? ReplaceWith | Exclude<T, ToReplace>
-        : {
+    : T extends Record<string, string> // Special exception for nexusHeader.
+      ? T
+      : T extends { [k: string]: ToReplace }
+        ? {
             [P in keyof T]: ReplaceNested<T[P], ToReplace, ReplaceWith>;
-          };
+          }
+        : T extends ToReplace
+          ? ReplaceWith | Exclude<T, ToReplace>
+          : {
+              [P in keyof T]: ReplaceNested<T[P], ToReplace, ReplaceWith>;
+            };
diff --git a/packages/core-bridge/Cargo.lock b/packages/core-bridge/Cargo.lock
index 395bf3c3b..111edac79 100644
--- a/packages/core-bridge/Cargo.lock
+++ b/packages/core-bridge/Cargo.lock
@@ -480,18 +480,18 @@ dependencies = [
 
 [[package]]
 name = "derive_more"
-version = "1.0.0"
+version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4a9b99b9cbbe49445b21764dc0625032a89b145a2642e67603e1c936f5458d05"
+checksum = "093242cf7570c207c83073cf82f79706fe7b8317e98620a47d5be7c3d8497678"
 dependencies = [
  "derive_more-impl",
 ]
 
 [[package]]
 name = "derive_more-impl"
-version = "1.0.0"
+version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cb7330aeadfbe296029522e6c40f315320aba36fc43a5b3632f3795348f3bd22"
+checksum = "bda628edc44c4bb645fbe0f758797143e4e07926f7ebf4e9bdfbd3d2ce621df3"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -809,23 +809,25 @@ checksum = "a8d1add55171497b4705a648c6b583acafb01d58050a51727785f0b2c8e0a2b2"
 
 [[package]]
 name = "governor"
-version = "0.7.0"
+version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0746aa765db78b521451ef74221663b57ba595bf83f75d0ce23cc09447c8139f"
+checksum = "be93b4ec2e4710b04d9264c0c7350cdd62a8c20e5e4ac732552ebb8f0debe8eb"
 dependencies = [
  "cfg-if",
  "dashmap",
  "futures-sink",
  "futures-timer",
  "futures-util",
+ "getrandom 0.3.2",
  "no-std-compat",
  "nonzero_ext",
  "parking_lot",
  "portable-atomic",
  "quanta",
- "rand 0.8.5",
+ "rand 0.9.1",
  "smallvec",
  "spinning_top",
+ "web-time",
 ]
 
 [[package]]
@@ -1201,15 +1203,6 @@ version = "2.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "469fb0b9cefa57e3ef31275ee7cacb78f2fdca44e4765491884a2b119d4eb130"
 
-[[package]]
-name = "itertools"
-version = "0.13.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "413ee7dfc52ee1a4949ceeb7dbc8a33f2d6c088194d9f922fb8318faf1f01186"
-dependencies = [
- "either",
-]
-
 [[package]]
 name = "itertools"
 version = "0.14.0"
@@ -1308,9 +1301,9 @@ checksum = "13dc2df351e3202783a1fe0d44375f7295ffb4049267b0f3018346dc122a1d94"
 
 [[package]]
 name = "lru"
-version = "0.12.5"
+version = "0.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "234cf4f4a04dc1f57e24b96cc0cd600cf2af460d4161ac5ecdd0af8e1f3b2a38"
+checksum = "227748d55f2f0ab4735d87fd623798cb6b664512fe979705f829c9f81c934465"
 dependencies = [
  "hashbrown 0.15.2",
 ]
@@ -1522,19 +1515,48 @@ dependencies = [
  "thiserror 1.0.69",
 ]
 
+[[package]]
+name = "opentelemetry"
+version = "0.26.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "570074cc999d1a58184080966e5bd3bf3a9a4af650c3b05047c2621e7405cd17"
+dependencies = [
+ "futures-core",
+ "futures-sink",
+ "js-sys",
+ "once_cell",
+ "pin-project-lite",
+ "thiserror 1.0.69",
+]
+
+[[package]]
+name = "opentelemetry-http"
+version = "0.26.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6351496aeaa49d7c267fb480678d85d1cd30c5edb20b497c48c56f62a8c14b99"
+dependencies = [
+ "async-trait",
+ "bytes",
+ "http",
+ "opentelemetry 0.26.0",
+ "reqwest",
+]
+
 [[package]]
 name = "opentelemetry-otlp"
-version = "0.17.0"
+version = "0.26.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6b925a602ffb916fb7421276b86756027b37ee708f9dce2dbdcc51739f07e727"
+checksum = "29e1f9c8b032d4f635c730c0efcf731d5e2530ea13fa8bef7939ddc8420696bd"
 dependencies = [
  "async-trait",
  "futures-core",
  "http",
- "opentelemetry",
+ "opentelemetry 0.26.0",
+ "opentelemetry-http",
  "opentelemetry-proto",
  "opentelemetry_sdk",
  "prost",
+ "reqwest",
  "thiserror 1.0.69",
  "tokio",
  "tonic",
@@ -1543,11 +1565,10 @@ dependencies = [
 [[package]]
 name = "opentelemetry-prometheus"
 version = "0.17.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cc4191ce34aa274621861a7a9d68dbcf618d5b6c66b10081631b61fd81fbc015"
+source = "git+https://github.com/open-telemetry/opentelemetry-rust.git?rev=e911383#e91138351a689cd21923c15eb48f5fbc95ded807"
 dependencies = [
  "once_cell",
- "opentelemetry",
+ "opentelemetry 0.26.0",
  "opentelemetry_sdk",
  "prometheus",
  "protobuf",
@@ -1555,11 +1576,11 @@ dependencies = [
 
 [[package]]
 name = "opentelemetry-proto"
-version = "0.7.0"
+version = "0.26.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "30ee9f20bff9c984511a02f082dc8ede839e4a9bf15cc2487c8d6fea5ad850d9"
+checksum = "c9d3968ce3aefdcca5c27e3c4ea4391b37547726a70893aab52d3de95d5f8b34"
 dependencies = [
- "opentelemetry",
+ "opentelemetry 0.26.0",
  "opentelemetry_sdk",
  "prost",
  "tonic",
@@ -1567,9 +1588,9 @@ dependencies = [
 
 [[package]]
 name = "opentelemetry_sdk"
-version = "0.24.1"
+version = "0.26.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "692eac490ec80f24a17828d49b40b60f5aeaccdfe6a503f939713afd22bc28df"
+checksum = "d2c627d9f4c9cdc1f21a29ee4bfbd6028fcb8bcf2a857b43f3abdf72c9c862f3"
 dependencies = [
  "async-trait",
  "futures-channel",
@@ -1577,7 +1598,7 @@ dependencies = [
  "futures-util",
  "glob",
  "once_cell",
- "opentelemetry",
+ "opentelemetry 0.26.0",
  "percent-encoding",
  "rand 0.8.5",
  "serde_json",
@@ -1795,7 +1816,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "be769465445e8c1474e9c5dac2018218498557af32d9ed057325ec9a41ae81bf"
 dependencies = [
  "heck",
- "itertools 0.14.0",
+ "itertools",
  "log",
  "multimap",
  "once_cell",
@@ -1815,7 +1836,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8a56d757972c98b346a9b766e3f02746cde6dd1cd1d1d563472929fdd74bec4d"
 dependencies = [
  "anyhow",
- "itertools 0.14.0",
+ "itertools",
  "proc-macro2",
  "quote",
  "syn",
@@ -2095,6 +2116,7 @@ checksum = "d19c46a6fdd48bc4dab94b6103fccc55d34c67cc0ad04653aad4ea2a07cd7bbb"
 dependencies = [
  "base64",
  "bytes",
+ "futures-channel",
  "futures-core",
  "futures-util",
  "http",
@@ -2519,9 +2541,9 @@ dependencies = [
 
 [[package]]
 name = "sysinfo"
-version = "0.32.1"
+version = "0.33.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4c33cd241af0f2e9e3b5c32163b873b29956890b5342e6745b917ce9d490f4af"
+checksum = "4fc858248ea01b66f19d8e8a6d55f41deaf91e9d495246fd01368d99935c6c01"
 dependencies = [
  "core-foundation-sys",
  "libc",
@@ -2571,11 +2593,10 @@ dependencies = [
  "hyper",
  "hyper-util",
  "parking_lot",
- "prost-types",
  "slotmap",
  "temporal-sdk-core-api",
  "temporal-sdk-core-protos",
- "thiserror 1.0.69",
+ "thiserror 2.0.12",
  "tokio",
  "tonic",
  "tower 0.5.2",
@@ -2605,10 +2626,10 @@ dependencies = [
  "http-body-util",
  "hyper",
  "hyper-util",
- "itertools 0.13.0",
+ "itertools",
  "lru",
  "mockall",
- "opentelemetry",
+ "opentelemetry 0.26.0",
  "opentelemetry-otlp",
  "opentelemetry-prometheus",
  "opentelemetry_sdk",
@@ -2618,7 +2639,7 @@ dependencies = [
  "prometheus",
  "prost",
  "prost-wkt-types",
- "rand 0.8.5",
+ "rand 0.9.1",
  "reqwest",
  "ringbuf",
  "rustfsm",
@@ -2631,12 +2652,11 @@ dependencies = [
  "temporal-client",
  "temporal-sdk-core-api",
  "temporal-sdk-core-protos",
- "thiserror 1.0.69",
+ "thiserror 2.0.12",
  "tokio",
  "tokio-stream",
  "tokio-util",
  "tonic",
- "tonic-build",
  "tracing",
  "tracing-subscriber",
  "url",
@@ -2651,12 +2671,11 @@ dependencies = [
  "async-trait",
  "derive_builder",
  "derive_more",
- "opentelemetry",
+ "opentelemetry 0.26.0",
  "prost",
- "prost-types",
  "serde_json",
  "temporal-sdk-core-protos",
- "thiserror 1.0.69",
+ "thiserror 2.0.12",
  "tonic",
  "tracing-core",
  "url",
@@ -2671,14 +2690,13 @@ dependencies = [
  "derive_more",
  "prost",
  "prost-build",
- "prost-types",
  "prost-wkt",
  "prost-wkt-build",
  "prost-wkt-types",
- "rand 0.8.5",
+ "rand 0.9.1",
  "serde",
  "serde_json",
- "thiserror 1.0.69",
+ "thiserror 2.0.12",
  "tonic",
  "tonic-build",
  "uuid",
@@ -2693,7 +2711,7 @@ dependencies = [
  "log",
  "neon",
  "once_cell",
- "opentelemetry",
+ "opentelemetry 0.24.0",
  "parking_lot",
  "prost",
  "prost-types",
@@ -2993,17 +3011,6 @@ dependencies = [
  "valuable",
 ]
 
-[[package]]
-name = "tracing-log"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ee855f1f400bd0e5c02d150ae5de3840039a3f54b025156404e34c23c03f47c3"
-dependencies = [
- "log",
- "once_cell",
- "tracing-core",
-]
-
 [[package]]
 name = "tracing-subscriber"
 version = "0.3.19"
@@ -3016,11 +3023,9 @@ dependencies = [
  "parking_lot",
  "regex",
  "sharded-slab",
- "smallvec",
  "thread_local",
  "tracing",
  "tracing-core",
- "tracing-log",
 ]
 
 [[package]]
diff --git a/packages/core-bridge/sdk-core b/packages/core-bridge/sdk-core
index dd37e2946..97093c5ea 160000
--- a/packages/core-bridge/sdk-core
+++ b/packages/core-bridge/sdk-core
@@ -1 +1 @@
-Subproject commit dd37e2946a385090ded0fc3312180027002d4b16
+Subproject commit 97093c5ea4b0d933513f4c8999f7960f0c16f05f
diff --git a/packages/core-bridge/src/conversions.rs b/packages/core-bridge/src/conversions.rs
index a60b716ef..4af913e62 100644
--- a/packages/core-bridge/src/conversions.rs
+++ b/packages/core-bridge/src/conversions.rs
@@ -504,6 +504,7 @@ impl ObjectHandleConversionsExt for Handle<'_, JsObject> {
                 temporal_sdk_core::ephemeral_server::EphemeralExe::CachedDownload {
                     version: exec_version,
                     dest_dir,
+                    ttl: None,
                 }
             }
             "existing-path" => {
diff --git a/packages/core-bridge/src/conversions/slot_supplier_bridge.rs b/packages/core-bridge/src/conversions/slot_supplier_bridge.rs
index 16748d97b..ae46a37c0 100644
--- a/packages/core-bridge/src/conversions/slot_supplier_bridge.rs
+++ b/packages/core-bridge/src/conversions/slot_supplier_bridge.rs
@@ -271,6 +271,10 @@ impl<SK: SlotKind> SlotSupplierBridge<SK> {
             SlotKindType::Workflow => "workflow",
             SlotKindType::Activity => "activity",
             SlotKindType::LocalActivity => "local-activity",
+            SlotKindType::Nexus => {
+                // This won't get hit as we'll not even try to run a Nexus poller
+                panic!("Nexus is not yet implemented");
+            }
         });
         context.set(cx, "slotType", slottype)?;
         let tq = cx.string(task_queue);
diff --git a/packages/core-bridge/src/worker.rs b/packages/core-bridge/src/worker.rs
index 8f58fcb08..d1cfc28f5 100644
--- a/packages/core-bridge/src/worker.rs
+++ b/packages/core-bridge/src/worker.rs
@@ -6,7 +6,7 @@ use std::{cell::RefCell, sync::Arc};
 use temporal_sdk_core::replay::HistoryForReplay;
 use temporal_sdk_core::{
     api::{
-        errors::{CompleteActivityError, CompleteWfError, PollActivityError, PollWfError},
+        errors::{CompleteActivityError, CompleteWfError, PollError},
         Worker as CoreWorkerTrait,
     },
     protos::{
@@ -181,8 +181,8 @@ async fn handle_poll_workflow_activation_request(
         }
         Err(err) => {
             send_error(channel, callback, move |cx| match err {
-                PollWfError::ShutDown => make_named_error_from_error(cx, SHUTDOWN_ERROR, err),
-                PollWfError::TonicError(_) => make_named_error_from_error(cx, TRANSPORT_ERROR, err),
+                PollError::ShutDown => make_named_error_from_error(cx, SHUTDOWN_ERROR, err),
+                PollError::TonicError(_) => make_named_error_from_error(cx, TRANSPORT_ERROR, err),
             });
         }
     }
@@ -208,10 +208,8 @@ pub async fn handle_poll_activity_task_request(
         }
         Err(err) => {
             send_error(channel, callback, move |cx| match err {
-                PollActivityError::ShutDown => make_named_error_from_error(cx, SHUTDOWN_ERROR, err),
-                PollActivityError::TonicError(_) => {
-                    make_named_error_from_error(cx, TRANSPORT_ERROR, err)
-                }
+                PollError::ShutDown => make_named_error_from_error(cx, SHUTDOWN_ERROR, err),
+                PollError::TonicError(_) => make_named_error_from_error(cx, TRANSPORT_ERROR, err),
             });
         }
     }
diff --git a/packages/worker/src/workflow-codec-runner.ts b/packages/worker/src/workflow-codec-runner.ts
index bc2b5ebbb..2fc43100b 100644
--- a/packages/worker/src/workflow-codec-runner.ts
+++ b/packages/worker/src/workflow-codec-runner.ts
@@ -72,7 +72,7 @@ export class WorkflowCodecRunner {
               cancelWorkflow: job.cancelWorkflow
                 ? {
                     ...job.cancelWorkflow,
-                    details: await decodeOptional(this.codecs, job.cancelWorkflow.details),
+                    details: null, // Not supported yet
                   }
                 : null,
               doUpdate: job.doUpdate
@@ -126,6 +126,16 @@ export class WorkflowCodecRunner {
                       : null,
                   }
                 : null,
+              resolveNexusOperationStart: job.resolveNexusOperationStart
+                ? ((() => {
+                    throw new Error('Nexus is not yet implemented');
+                  }) as any)
+                : null,
+              resolveNexusOperation: job.resolveNexusOperation
+                ? ((() => {
+                    throw new Error('Nexus is not yet implemented');
+                  }) as any)
+                : null,
               resolveChildWorkflowExecution: job.resolveChildWorkflowExecution
                 ? {
                     ...job.resolveChildWorkflowExecution,
@@ -316,6 +326,12 @@ export class WorkflowCodecRunner {
                               },
                             }
                           : undefined,
+                        scheduleNexusOperation: command.scheduleNexusOperation
+                          ? {
+                              ...command.scheduleNexusOperation,
+                              nexusHeader: command.scheduleNexusOperation.nexusHeader ?? undefined,
+                            }
+                          : undefined,
                       }
                   ) ?? []
                 )
diff --git a/packages/workflow/src/internals.ts b/packages/workflow/src/internals.ts
index 93f8fd598..c92f5e4f7 100644
--- a/packages/workflow/src/internals.ts
+++ b/packages/workflow/src/internals.ts
@@ -523,6 +523,16 @@ export class Activator implements ActivationHandler {
     }
   }
 
+  public resolveNexusOperationStart(_activation: coresdk.workflow_activation.IResolveNexusOperationStart): void {
+    // This will never be called as we can't produce Nexus-related commands anyway
+    throw new Error('Nexus is not yet implemented');
+  }
+
+  public resolveNexusOperation(_activation: coresdk.workflow_activation.IResolveNexusOperation): void {
+    // This will never be called as we can't produce Nexus-related commands anyway
+    throw new Error('Nexus is not yet implemented');
+  }
+
   public resolveChildWorkflowExecutionStart(
     activation: coresdk.workflow_activation.IResolveChildWorkflowExecutionStart
   ): void {