Multi-stage builds · Knowledge & Memory Center

Steps

STEP 1 OF 7

Start a build stage with the full SDK: FROM <sdk-image> AS build

Example: Spring Boot

Dockerfile

DOCKERFILE

1FROM maven:3.9-eclipse-temurin-21 AS build

2WORKDIR /src

3COPY pom.xml .

4RUN mvn -q dependency:go-offline

5COPY src ./src

6RUN mvn -q package -DskipTests

7

8FROM eclipse-temurin:21-jre-alpine

9WORKDIR /app

10COPY --from=build /src/target/*.jar app.jar

11USER 1000

12EXPOSE 8080

13ENTRYPOINT ["java", "-jar", "app.jar"]

Example: React / static site

Dockerfile

DOCKERFILE

1FROM node:20-alpine AS build

2WORKDIR /app

3COPY package*.json ./

4RUN npm ci

5COPY . .

6RUN npm run build

7

8FROM nginx:1.27-alpine

9COPY --from=build /app/dist /usr/share/nginx/html

10EXPOSE 80

Tip

Build a single stage for testing with docker build --target build -t myapp:build .. Stages that the final stage does not depend on are skipped automatically by BuildKit.