diff --git a/nixbot.toml b/nixbot.toml
index 90a447ec..df14aa74 100644
--- a/nixbot.toml
+++ b/nixbot.toml
@@ -1 +1,4 @@
 attribute = "ci.nixbot"
+# Additional branches to build on push.
+# The default branch and merge-queue branches always build.
+build_branches = ["nixos-*"]