Last Updated: November 21, 2025
Optimization Focus
| Feature | Why use it |
|---|---|
Cache mounts
|
Mount type=cache for package downloads and tools. |
Secret mounts
|
Keep credentials out of images with RUN --mount=type=secret. |
Multi-stage builds
|
Separate builder dependencies from runtime artifacts. |
Concurrent steps
|
BuildKit executes independent steps in parallel. |
Build Commands
DOCKER_BUILDKIT=1 docker build --secret id=npmrc,src=.npmrc .
Provide private registry credentials securely.
docker buildx build --cache-from=type=registry,ref=repo:cache --cache-to=type=inline
Push caches for CI reuse.
RUN --mount=type=cache,target=/root/.cache/pip pip install -r requirements.txt
Speed up Python builds.
docker buildx du --progress=plain
Inspect cache layers and size.
Summary
BuildKit speeds up builds by caching downloads, isolating secrets, and running independent steps simultaneously.
💡 Pro Tip:
Enable BuildKit by default with DOCKER_BUILDKIT=1 and monitor docker buildx du for cache usage.