Caching and artifacts · Knowledge & Memory Center

Cache vs artifact

	Cache	Artifact
Purpose	Speed: reuse dependencies across runs	Output: pass files between jobs / download
Typical content	`~/.m2`, `~/.npm`, Docker layers	JAR, `dist/`, test reports, coverage
Lifetime	Evicted after ~7 days unused, 10 GB per repo	Retention 1-90 days (default 90)
Keyed by	`key:` (usually a lockfile hash)	`name:`

Built-in caching (easiest)

setup-* actions cache for you

YAML

1- uses: actions/setup-node@v7

2 with: { node-version: '22', cache: npm } # keyed on package-lock.json

3

4- uses: actions/setup-java@v6

5 with: { distribution: temurin, java-version: '25', cache: maven } # keyed on pom.xml

6

7# Docker layers: see build-push-action cache-from/cache-to type=gha

Artifacts between jobs

upload in build, download in deploy

YAML

1build:

2 runs-on: ubuntu-latest

3 steps:

4 - uses: actions/checkout@v7

5 - run: mvn -B package -DskipTests

6 - uses: actions/upload-artifact@v7

7 with:

8 name: app-jar # handle for download

9 path: target/*.jar

10 retention-days: 5 # keep storage small

11

12deploy:

13 needs: build

14 runs-on: ubuntu-latest

15 steps:

16 - uses: actions/download-artifact@v8

17 with:

18 name: app-jar

19 path: dist/

20 - run: ls -la dist/

!

Upload and download artifact actions must use matching major versions. Check the action README for the current pair when upgrading.

Tip

Test reports: upload with if: always() so you get them even when tests fail. Keep caches keyed on lockfiles, not on branch names, so every branch benefits.