Node.js4 min read2026-03-01

npm Dependency Conflict: ERESOLVE unable to resolve dependency tree

Troubleshoot npm peer dependency conflicts, conflicting version constraints, and package-lock issues.

Error Code / Stack Trace

npm ERR! code ERESOLVE
npm ERR! ERESOLVE unable to resolve dependency tree

Two packages in your dependency tree require incompatible peer dependency versions of the same library (e.g. React 18 vs React 19).

Upgraded a root package while third-party plugins still specify an older peerDependency range.
npm v7+ strict peer dependency enforcement algorithm.

Bypass strict peer dependency locking if the package functions properly.

bash

npm install --legacy-peer-deps

Force all child dependencies to accept a specific unified version of the conflicting package.

json

{
  "dependencies": {
    "react": "^19.0.0"
  },
  "overrides": {
    "react": "^19.0.0"
  }
}

•Deleting package-lock.json and running npm install, which can pull breaking minor/patch updates across all dependencies.

dependencies are installed privately inside a library. peerDependencies require the consumer application to provide the shared dependency instance.