Dockerfile Linter runs lightweight heuristics on pasted Dockerfiles: floating latest tags, missing USER, apt-get without cleanup, and ENV lines that look like secrets. Use it for quick reviews before a deeper Hadolint pass.
What Dockerfile Linter does
Reports warning-level findings.
- FROM ...:latest detection
- Missing USER instruction
- apt without rm lists cleanup
- ENV keys that look like secrets
Who Dockerfile Linter is for
- Container developers
- Reviewers scanning PRs
- Students learning Docker hygiene
- Platform engineers drafting base images
How to use Dockerfile Linter
1. Paste your Dockerfile.
2. Click Lint.
3. Read warnings with line numbers.
4. Copy the report into a review note.
Features
- Client-side only
- Line-oriented messages
- Related nginx and env tools
- Honest best-effort scope
Examples
- Flag FROM node:latest.
- Note a missing non-root USER.
- Warn on ENV AWS_SECRET_ACCESS_KEY=...
Tips and limits
- Not a substitute for Hadolint or Trivy.
- Multi-stage files may need manual judgment.
- False positives are possible on unusual patterns.
- Secrets should use build secrets, not ENV.
Related tools
FAQ
Is this Hadolint?
No. It is a smaller heuristic checker for common issues.
Is my Dockerfile uploaded?
No. Linting is local.
Extra notes
Dockerfile Linter runs entirely in your browser so drafts and secrets never need to leave your device for processing. Keep a backup of long outputs in your own notes if you rely on them for production servers or live events. Accessibility friendly labels come from the module UI strings, and the layout follows the shared BeeForge .bf-tool shell for consistent spacing and buttons.
Support for developers, marketers, and everyday users is the same client-side model: open the page, configure options, copy or download, then paste into your workflow. BeeForge related links on the tool page point to companion utilities so you can move between related generators without hunting the hub.
When you share results with a teammate, paste into a ticket or gist rather than screenshotting alone, so the text remains searchable. If a browser privacy mode blocks clipboard helpers, select the output manually. Local processing also means the tool works offline after the page and scripts have loaded once.
Validate generated configs or hashes in a staging environment before production use. Prefer regenerating secrets after any accidental paste into chat. For teaching sessions, walk through one sample input end to end so students see how live updates and copy buttons behave together.