diff --git a/.gitmodules b/.gitmodules
index 66f1c6f..eaef5e5 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -103,3 +103,6 @@
 [submodule "vendor/nim-poseidon2"]
 	path = vendor/nim-poseidon2
 	url = https://github.com/codex-storage/nim-poseidon2.git
+[submodule "vendor/constantine"]
+	path = vendor/constantine
+	url = https://github.com/mratsim/constantine.git
diff --git a/vendor/constantine b/vendor/constantine
new file mode 160000
index 0000000..8d6a6a3
--- /dev/null
+++ b/vendor/constantine
@@ -0,0 +1 @@
+Subproject commit 8d6a6a38b90fb8ee3ec2230839773e69aab36d80