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.

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Examples

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