Docker Helper

Dockerfile Best Practices

Layer Caching and .dockerignore

Order instructions from least to most frequently changing. Copy dependency manifests before source code.

FROM node:20-alpine
WORKDIR /app
COPY package.json package-lock.json ./
RUN npm ci --omit=dev
COPY . .
CMD ["node", "server.js"]

Always include a .dockerignore to reduce build context and prevent secret leaks: