Set (sub)domain name via environment
diff --git a/nginx/Dockerfile b/nginx/Dockerfile
index 18cbc8e..9809c58 100644
--- a/nginx/Dockerfile
+++ b/nginx/Dockerfile
@@ -23,3 +23,9 @@
 
 
 FROM nginx_${SSL_VARIANT}
+
+COPY nginx/Dockerfile.entrypoint /nginx-entrypoint
+RUN chmod 544 /nginx-entrypoint
+
+ENTRYPOINT ["/bin/sh", "/nginx-entrypoint"]
+CMD ["nginx", "-g", "daemon off;"]