#docker

depends_on alone is not enough - healthchecks change everything: a tour of the Compose tricks that make a dev stack reliable - startup order, profiles, overrides and the !override tag, include, YAML anchors, watch mode, lifecycle hooks, parallel stacks, and tmpfs test databases.

Layer ordering, .dockerignore, multi-stage builds, cache mounts, non-root users: the techniques that turn a naive Dockerfile into a lightweight image, fast to rebuild and sound in production.