diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..797affe
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,6 @@
+[submodule "external/libds"]
+	path = external/libds
+	url = http://dev.danilafe.com/Experiments/libds.git
+[submodule "external/liblex"]
+	path = external/liblex
+	url = http://dev.danilafe.com/Experiments/liblex.git
diff --git a/external/libds b/external/libds
new file mode 160000
index 0000000..276d38a
--- /dev/null
+++ b/external/libds
@@ -0,0 +1 @@
+Subproject commit 276d38a292bc03939e854deac077b7d71b21eb8e
diff --git a/external/liblex b/external/liblex
new file mode 160000
index 0000000..bb07382
--- /dev/null
+++ b/external/liblex
@@ -0,0 +1 @@
+Subproject commit bb07382b5986ccd1ee6ba76717316d87a9808b99