diff --git a/Dockerfile b/Dockerfile
index 403016b..fe76573 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -7,7 +7,8 @@ WORKDIR /app
 
 COPY . .
 
-RUN apk add make git && make build VERSION=$VERSION
+RUN apk add make git upx && make build VERSION=$VERSION \
+    && upx --best --lzma whatismyip
 
 # Build final image
 FROM scratch
diff --git a/README.md b/README.md
index 539673b..c8cb1c3 100644
--- a/README.md
+++ b/README.md
@@ -138,7 +138,7 @@ Download the latest version from https://github.com/dcarrillo/whatismyip/release
 
 ## Docker
 
-An ultra-light (~12MB) image is available at [docker hub](https://hub.docker.com/r/dcarrillo/whatismyip).
+An ultra-light (~4MB) image is available on [docker hub](https://hub.docker.com/r/dcarrillo/whatismyip). Since version `2.1.2`, the binary is compressed using [upx](https://github.com/upx/upx).
 
 ### Run a container locally using test databases