diff --git a/nixos/modules/services/continuous-integration/buildbot/master.nix b/nixos/modules/services/continuous-integration/buildbot/master.nix
index 595374ea1e5..b4b997201c8 100644
--- a/nixos/modules/services/continuous-integration/buildbot/master.nix
+++ b/nixos/modules/services/continuous-integration/buildbot/master.nix
@@ -272,7 +272,13 @@ in {
         Group = cfg.group;
         WorkingDirectory = cfg.home;
         # NOTE: call twistd directly with stdout logging for systemd
-        ExecStart = "${python.pkgs.twisted}/bin/twistd -o --nodaemon --pidfile= --logfile - --python ${tacFile}";
+        ExecStart = "${python.pkgs.twisted}/bin/twistd -o --nodaemon --pidfile= --logfile - --python ${cfg.buildbotDir}/buildbot.tac";
+        # To reload on upgrade, set the following in your configuration:
+        # systemd.services.buildbot-master.reloadIfChanged = true;
+        ExecReload = [
+          "${pkgs.coreutils}/bin/ln -sf ${tacFile} ${cfg.buildbotDir}/buildbot.tac"
+          "${pkgs.coreutils}/bin/kill -HUP $MAINPID"
+        ];
       };
     };
   };