Your CI Docker build reruns every layer on every push. With the right layer ordering, BuildKit cache mounts, and remote caching, you can cut a 4-minute build to under 30 seconds. Here is exactly how.
The dev environment that works on your machine but not on your teammates costs hours of setup time and silently diverges until production breaks. Here is the VS Code Dev Containers setup that gives every engineer the same Node.js version, Postgres port, and system dependencies from a single JSON file.
Your orchestrator does not know your container is broken until a user hits it. Docker HEALTHCHECK fills that gap with a three-parameter config and a deliberately boring HTTP endpoint that separates startup, liveness, and readiness into distinct states.
A practical guide to running Node.js containers with least privilege: dropping Linux capabilities, switching to a non-root user, enabling read-only root filesystems, and applying seccomp profiles so a container breakout is significantly harder.
Your M2 Mac builds a working Docker image. Your AMD64 production server crashes with "exec format error" or segfaults on a native addon. Here is the buildx setup, QEMU binfmt registration, platform-specific dependency handling, and GitHub Actions workflow that makes one Dockerfile produce images for arm64 and amd64 that actually work.
The Docker Compose setup that worked on day one is broken by day thirty: stale volumes, mismatched bind mounts, services that start before the database is ready. Here is the pattern for local dev environments that survive a team of ten without every other developer running a different setup.
A step-by-step optimization of a real Node.js Docker image, from a 1.2GB monster to a 78MB production container. Each technique is benchmarked, copy-paste ready, and explained with the trade-offs.