ESLint "Command failed with exit code 1" on lint errors in CI

By Daniel Zoghalchali·Latchkey

ESLint exits 1 whenever it reports at least one error-level problem. The job is not broken: the lint gate is working, and the fix is to resolve (or downgrade) the reported rule violations.

What this error means

The lint step prints a list of file:line errors and ends with "error Command failed with exit code 1." or "Process completed with exit code 1.". A clean run exits 0.

/home/runner/work/app/app/src/api.ts
  12:7  error  'data' is assigned a value but never used  @typescript-eslint/no-unused-vars

x 1 problem (1 error, 0 warnings)
error Command failed with exit code 1.

Common causes

Real error-level rule violations

One or more rules configured as error were triggered. ESLint returns exit code 1 for any error, which is the intended CI gate.

New code or stricter rules surfaced issues

A merged change introduced violations, or a rule was promoted from warn to error, so previously passing code now fails.

How to fix it

Read and fix the reported errors

1. Read the file:line and rule name in each error.
2. Fix the code, or auto-fix the fixable ones.
3. Re-run locally until ESLint exits 0.

npx eslint . --fix
npx eslint .   # confirm exit 0

Reclassify a rule deliberately if it is noise

If a rule should not block, set it to warn (or off) in config rather than ignoring exit code 1 globally.

// eslint.config.js
rules: { '@typescript-eslint/no-unused-vars': 'warn' }

How to prevent it

• Run ESLint locally or in a pre-commit hook before pushing.
• Promote rules to error intentionally and fix the backlog first.
• Keep the lint config in sync between local and CI.

Frequently asked questions

Related guides

References

• Node.js documentation
• npm CLI documentation
• GitHub Actions documentation