Define and run multi-target builds with docker buildx bake

Steps

1. Create a docker-bake.hcl (or docker-bake.json) file at the repository root; define a group and multiple targets, each with its own context, dockerfile, tags, and platforms
2. Define shared configuration in a variable block or by using inherits to avoid repeating platform or cache settings across targets; example: target 'base' { ... } then target 'app' { inherits = ['base']; ... }
3. Add cache-from and cache-to inside each target block using the same type= syntax as buildx: cache-to = ["type=registry,ref=YOUR_REGISTRY/myapp-TARGET:cache,mode=max"]
4. Run all targets in parallel with docker buildx bake --push; add --print first to validate the resolved bake definition without building
5. Override individual target values from the CLI without editing the file: docker buildx bake --set target.tags=myapp:dev-SHA to inject a dynamic tag in CI
6. Use a matrix strategy in GitHub Actions to run docker buildx bake across multiple bake files or target subsets if the full bake graph is too large to run in one job