diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..d3cda9d
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "spec"]
+	path = spec
+	url = https://tildegit.org/forge/endpoints
diff --git a/spec b/spec
new file mode 160000
index 0000000..e81a3b4
--- /dev/null
+++ b/spec
@@ -0,0 +1 @@
+Subproject commit e81a3b4b25c6f549e67954f0eafbd7b421832e15