diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 000000000..393132806
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "ext/cppformat"]
+	path = ext/cppformat
+	url = https://github.com/cppformat/cppformat.git
diff --git a/ext/cppformat b/ext/cppformat
new file mode 160000
index 000000000..0b097da31
--- /dev/null
+++ b/ext/cppformat
@@ -0,0 +1 @@
+Subproject commit 0b097da31eae1642dd8132f2996e74f7fe354e46