Include git2/worktree.h in git2.h I'm not sure if worktree.h was intentionally left out of git2.h. Looks like an oversight since it is in fact documented.
diff --git a/include/git2.h b/include/git2.h
index bc4333c..5f6104e 100644
--- a/include/git2.h
+++ b/include/git2.h
@@ -62,5 +62,6 @@
#include "git2/tree.h"
#include "git2/types.h"
#include "git2/version.h"
+#include "git2/worktree.h"
#endif