Migrate to Yarn 4

.yarnrc.yml

@@ -1,7 +1,7 @@
-nodeLinker: node-modules
+compressionLevel: mixed
+
+enableGlobalCache: false
 
-plugins:
-  - path: .yarn/plugins/@yarnpkg/plugin-typescript.cjs
-    spec: "@yarnpkg/plugin-typescript"
+nodeLinker: node-modules
 
-yarnPath: .yarn/releases/yarn-3.5.1.cjs
+yarnPath: .yarn/releases/yarn-4.9.1.cjs

CONTRIBUTING.md

@@ -78,7 +78,7 @@ Full example: `yarn release @langchain/langgraph --bump-deps --tag beta`.
 This project uses the following tools, which are worth getting familiar
 with if you plan to contribute:
 
-- **[yarn](https://yarnpkg.com/) (v3.4.1)** - dependency management
+- **[yarn](https://yarnpkg.com/) (v4.9.1)** - dependency management
 - **[eslint](https://eslint.org/)** - enforcing standard lint rules
 - **[prettier](https://prettier.io/)** - enforcing standard code formatting
 - **[jest](https://jestjs.io/)** - testing code

libs/checkpoint/package.json

@@ -86,4 +86,4 @@
     "index.d.ts",
     "index.d.cts"
   ]
-}
+}

libs/langgraph-supervisor/package.json

@@ -92,4 +92,4 @@
   "resolutions": {
     "typescript": "4.9.5"
   }
-}
+}

libs/langgraph/package.json

@@ -184,4 +184,4 @@
     "zod/schema.d.ts",
     "zod/schema.d.cts"
   ]
-}
+}

package.json

@@ -3,7 +3,7 @@
   "private": true,
   "description": "LangGraph",
   "type": "module",
-  "packageManager": "yarn@3.5.1",
+  "packageManager": "yarn@4.9.1",
   "engines": {
     "node": ">=18"
   },