diff --git a/README.md b/README.md
index 060187f..c537b74 100644
--- a/README.md
+++ b/README.md
@@ -178,8 +178,7 @@ The entrypoint of the image is the `run` command.
 
 To build the image:
 ```
-cd docker
-docker build -t novnc/websockify .
+./docker/build.sh
 ```
 
 Once built you can just launch it with the same
diff --git a/docker/Dockerfile b/docker/Dockerfile
index f9cb72b..1ae078b 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -1,12 +1,9 @@
-FROM python:3.6
+FROM python
 
-ENV VERSION 0.10.0
+COPY websockify-*.tar.gz /
 
-RUN mkdir -p /opt/websockify \
-    && curl -SL https://github.com/novnc/websockify/archive/refs/tags/v$VERSION.tar.gz \
-    | tar xzC /opt/websockify
-
-RUN python -m pip install 'numpy<1.17' redis simplejson jwcrypto requests
+RUN python3 -m pip install websockify-*.tar.gz
+RUN rm -rf /websockify-* /root/.cache
 
 VOLUME /data
 
@@ -15,7 +12,5 @@ EXPOSE 443
 
 WORKDIR /opt/websockify
 
-COPY docker-entrypoint.sh /
-
-ENTRYPOINT ["/docker-entrypoint.sh"]
+ENTRYPOINT ["/usr/local/bin/websockify"]
 CMD ["--help"]
diff --git a/docker/build.sh b/docker/build.sh
new file mode 100755
index 0000000..1f85626
--- /dev/null
+++ b/docker/build.sh
@@ -0,0 +1,5 @@
+#!/usr/bin/env sh
+set -e -x
+cd "$(dirname "$0")"
+(cd .. && python3 setup.py sdist --dist-dir docker/)
+docker build -t novnc/websockify .
diff --git a/docker/docker-entrypoint.sh b/docker/docker-entrypoint.sh
deleted file mode 100755
index 1178553..0000000
--- a/docker/docker-entrypoint.sh
+++ /dev/null
@@ -1,6 +0,0 @@
-#!/bin/sh
-# vim: tabstop=4 shiftwidth=4 softtabstop=4
-
-set -e
-
-/opt/websockify/websockify-$VERSION/run "$@"