diff --git a/README.md b/README.md
index 05a9c48..f295fe6 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,9 @@
+# Tarball
+
+```bash
+nix build .#nixosConfigurations.matrix.config.system.build.image
+```
+
 # HTTP
 
 Configure `berlin.ccc.de` web server to send federation traffic to the matrix server: