Persisting Cache Directories

Persisting Cache Directories

Modern software development relies on countless dependencies

Filling caches takes time

BuildKit to the rescue

Cache directories can be persisted

Syntax is similar to mounting secrets

#syntax=docker/dockerfile:1.2
FROM ubuntu
RUN --mount=type=cache,target=/tmp/cache \
    ls -l /tmp/cache

Demo: Persisting Cache Directories

Enable BuildKit:

export DOCKER_BUILDKIT=1

Run build:

docker build \
    --progress plain \
    --file Dockerfile.cache-warm \
    .

Run build:

docker build \
    --progress plain \
    --file Dockerfile.cache-check \
    .