diff --git a/git.zig b/git.zig
index aff4e73c553c50bf931a78e6c775f9be9e085c59..6a6635b644a4a516e3a02efeb54b9e0a99934f53 100644
--- a/git.zig
+++ b/git.zig
@@ -139,6 +139,7 @@ pub const Tree = struct {
         pub const Id = union(enum) {
             blob: BlobId,
             tree: TreeId,
+            commit: CommitId,
 
             pub const Tag = std.meta.Tag(@This());
         };