diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..6474c8d
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "vendor/callable"]
+	path = vendor/callable
+	url = forgejo@git.objectionable.solutions:Sara/cpp-callable.git
diff --git a/vendor/callable b/vendor/callable
new file mode 160000
index 0000000..64f1dda
--- /dev/null
+++ b/vendor/callable
@@ -0,0 +1 @@
+Subproject commit 64f1ddaa36ad8aa412173668995d7b3434ecc4e3