diff --git a/Dockerfile b/Dockerfile
index 2cafcd6..090e6d5 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,10 +1,10 @@
-FROM golang:1.13.5-alpine3.10 as builder
+FROM golang:1.15.3-alpine3.12 as builder
 RUN apk add --update --no-cache ca-certificates git tzdata
 WORKDIR /tmp/dnsupdater
 COPY go.mod go.sum ./
 RUN go mod download
 COPY ./ ./
-RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o dnsupdater .
+RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o dnsupdater ./cmd/dnsupdater
 
 FROM busybox:glibc
 COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt