dockerfile-cache-xp

Push BuildKit layer-cache reuse to the limit: turn a CI Dockerfile into a Dockerfile.local that survives source-only edits in minutes instead of rebuilding from scratch — and hand over the nerdctl command that runs it.

The CI Dockerfile is built for reproducibility from a clean state, not for iteration. A local build pays that full cost every time. The local version keeps the CI stage structure and rewrites each RUN to ride cache mounts across builds.

Output

Two artifacts, placed next to the original:

1. <name>.local — the optimized Dockerfile (same directory as the source, .local suffix). Preserves the original's stage structure; only changes how each stage caches.
2. The nerdctl build command — printed to the user, ready to run.