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Node.js (basic)
Node.js (multi-stage)
Python + Poetry
Go (scratch)
Your own
Dockerfile
read-only1 stage2 total layers
Stage 1
FROM node:latestlatestfinalWORKDIR
/app
metadataCOPY
. .
layerRUN
npm install
layerEXPOSE
3000
metadataCMD
npm start
metadata2 layers5 instructions
Best Practices
2 warnings2 hintsStage 1 uses "node:latest" without a pinned tag. Pin a specific version for reproducible builds.
Copying all files before installing dependencies busts the cache on every code change. Copy dependency manifests first, install, then copy the rest.
L4No USER instruction in the final stage. The container will run as root by default.
No HEALTHCHECK in the final stage. Adding one helps orchestrators detect unhealthy containers.