6 min readcode.live
Dockerfile Best Practices: A Checklist, Not a Wall of Text
Layer caching, multi-stage builds, non-root users, .dockerignore — the practical checklist for a Dockerfile that builds fast and stays small.
Order matters more than people think
Docker caches layers top-down and invalidates everything below the first changed line. Copying dependency manifests (package.json, requirements.txt) and installing dependencies before copying the rest of your source code means code changes don't bust your dependency cache on every build.
The checklist
- Multi-stage builds to keep build tools out of the final image
- Pin base image versions — 'latest' silently changes underneath you
- Run as a non-root user in the final stage
- Add a .dockerignore so node_modules/.git don't bloat the build context
- Combine RUN commands where it reduces layer count without hurting cache granularity
- Use COPY --chown instead of a separate chown RUN step
Try it on code.live
code.live's Dockerfile Generator scaffolds a multi-stage Dockerfile for common stacks (Node, Python, Go) with these practices baked in, as a starting point instead of a blank file.
Key takeaways
- Apply one concrete change from this post before collecting more reading.
- Prefer browser-side tools when the work involves secrets, tokens, or PII.
- Document the why next to the how so the next reviewer inherits context.
FAQ
- Who is this guide on docker for?
- Working developers who need a practical take on dockerfile best practices: a checklist, not a wall of text — not a marketing overview. Skim the sections, apply one tip, then come back when you hit an edge case.
- Do I need an account to use the related tools?
- No. code.live tools run in your browser with no signup. Nothing you paste is uploaded to a server for the client-side utilities linked from this post.
- How often is this article updated?
- This post was published August 22, 2026. Fundamentals stay stable; check linked tool pages and official docs when version-specific behavior matters.