diff --git a/.gitignore b/.gitignore
index 13c74945b..46446326b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,8 @@ devAssets
 
 .DS_Store
 .ideapackage-lock.json
+
+# Runtime config — managed directly on each deploy host, never committed.
+# Contains the GIF API key and homeserver list. git reset --hard won't touch
+# it but git clean would delete it without this entry.
+config.json