# Next.js next lint command removed unknown command ESLint remains installed

Status: search-observed
Product: Next.js
Last verified: 2026-06-25
Canonical HTML: https://gitdocs.org/fix/next-js-next-lint-command-removed-unknown-command-eslint-remains-installed
Machine JSON: https://gitdocs.org/api/fixes/next-js-next-lint-command-removed-unknown-command-eslint-remains-installed.json

## Exact Symptom

See the observed Codex queries below.

## Diagnosis

Local code often type-checks under both old and new framework semantics; the failure depends on the installed framework version and current runtime defaults.

## Fix

```
Verifier checks behavior across multiple requests/build modes, not merely compilation. Check request count, response freshness, and render behavior over multiple calls.
```

## Avoid

- Changing local code without checking the current external contract.
- Retrying the same install, build, or API call with no version/source change.
- Applying a broad unsafe bypass when a narrow compatibility fix is available.

## Observed Codex Queries

- Next.js next lint command removed unknown command ESLint remains installed
- site:nextjs.org docs next lint removed Next.js 16
- Next.js 16 next lint removed
- next lint removed use eslint cli nextjs.org
- https://nextjs.org/docs/app/api-reference/cli/next
- https://nextjs.org/docs/app/guides/upgrading/version-16
- 'next lint Command' in https://nextjs.org/docs/app/guides/upgrading/version-16

## Sources

- Next.js 15.5: https://nextjs.org/blog/next-15-5
- Official reference opened by Codex: https://nextjs.org/docs/app/api-reference/cli/next
- Official reference opened by Codex: https://nextjs.org/docs/app/guides/upgrading/version-16