Build backend inside docker multi-stage build

api/Dockerfile

@@ -1,3 +1,17 @@
+FROM maven:3.6.3-jdk-13 as builder
+
+WORKDIR /tmp
+
+# Cache dependencies
+COPY pom.xml .
+RUN mvn verify clean --fail-never
+
+COPY resources resources
+COPY src src
+COPY test test
+
+RUN mvn package
+
 FROM openjdk:13-alpine
 
 ENV APPLICATION_USER ktor
@@ -8,7 +22,7 @@ RUN chown -R $APPLICATION_USER /app
 
 USER $APPLICATION_USER
 
-COPY ./target/api-0.0.1-jar-with-dependencies.jar /app/notes-api.jar
+COPY --from=builder /tmp/target/api-*-jar-with-dependencies.jar /app/notes-api.jar
 WORKDIR /app
 
 CMD ["java", "-server", "-XX:+UnlockExperimentalVMOptions", "-XX:InitialRAMFraction=2", "-XX:MinRAMFraction=2", "-XX:MaxRAMFraction=2", "-XX:+UseG1GC", "-XX:MaxGCPauseMillis=100", "-XX:+UseStringDeduplication", "-jar", "notes-api.jar"]