Vaše Docker image má 5 GB? Tady je jak ji dostat na 50 MB.

Krok 1: Změřte¶

docker images myapp
docker history myapp:latest

Krok 2: Alpine base¶

FROM node:20 → 1.1 GB¶

FROM node:20-alpine # → 180 MB

Krok 3: Multi-stage build¶

FROM node:20-alpine AS build
WORKDIR /app
COPY package*.json ./
RUN npm ci –production
COPY . .
RUN npm run build

FROM node:20-alpine
COPY –from=build /app/dist ./dist
COPY –from=build /app/node_modules ./node_modules
CMD [“node”, “dist/index.js”]

Krok 4: Distroless¶

FROM gcr.io/distroless/nodejs20-debian12
COPY –from=build /app/dist /app
CMD [“/app/index.js”]

Krok 5: .dockerignore¶

node_modules .git *.md Dockerfile tests

Krok 6: Minimalizujte vrstvy¶

RUN apt-get update && apt-get install -y curl && rm -rf /var/lib/apt/lists/*

Výsledky¶

• node:20 = 1.1 GB
• node:20-alpine = 180 MB
• Multi-stage + alpine = 80 MB
• Distroless = 50 MB
• Go static binary + scratch = 10 MB

Tip¶

Menší image = rychlejší deploy, méně attack surface, méně storage. Vždy se vyplatí.