Layerfile Reference

CACHE [cached directories...]

The CACHE instruction makes specific files/directories be shared across runs, almost always as a performance improvement.

See the tuning performance documentation for more details.


  • Use CACHE /var/cache/apt to speed up RUN apt-get update
  • Use CACHE ~/.cache/go-build to speed up RUN go install
  • Use CACHE ~/.npm ~/.next/cache ~/.yarn/cache to speed up npm install and yarn install

Each account gets a fixed amount of cache storage, and we periodically delete old or inactive caches.