Using multistage build for Dockerfile

Dockerfile

@@ -1,11 +1,17 @@
-FROM golang:1.16-alpine
+FROM golang:1.16 AS builder
 
 WORKDIR /go/src/app
 COPY . .
 
-RUN go get -d -v ./...
-RUN go install -v ./...
+RUN CGO_ENABLED=0 GOOS=linux go get -d -v . && \
+	go build -a -tags netgo -o b56
+
+FROM alpine:3.14
+
+WORKDIR /app
+COPY --from=builder /go/src/app/b56 .
+COPY ./static ./static
 
 EXPOSE 80
 
-CMD ["b56"]
+CMD ["/app/b56"]