npm ERR ERESOLVE Fix

ERESOLVE means npm cannot produce a dependency tree that satisfies peer dependency constraints. Read the conflicting packages before forcing install.

Symptoms

  • npm install fails with ERESOLVE unable to resolve dependency tree.
  • The error mentions peer dependency conflicts.
  • A package upgrade breaks installation.

Likely causes

  • Package versions require incompatible peer dependencies.
  • Lock file and package.json drifted.
  • A framework plugin expects a different major version.

Fix steps

  1. Read the peer dependency lines and identify the incompatible package.
  2. Upgrade or downgrade the package pair intentionally.
  3. Avoid --force unless you accept runtime risk.

Verify the fix

  • Delete node_modules only after understanding the conflict.
  • Run npm install and npm test/build.
  • Commit lock file changes intentionally.

FAQ

Should I use --legacy-peer-deps?

Only as a temporary compatibility workaround after reviewing the conflict.

Is deleting package-lock enough?

Not usually. It may hide the version conflict rather than fix it.

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Last updated: May 18, 2026