diff --git a/.gitmodules b/.gitmodules
index e55c450..19f0e34 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,13 +1,3 @@
-[submodule "zto"]
-	path = zto
-	url = https://github.com/zerotier/ZeroTierOne.git
-	branch = dev
-[submodule "ext/lwip"]
-	path = ext/lwip
-	url = https://git.savannah.nongnu.org/git/lwip.git
-[submodule "ext/lwip-contrib"]
-	path = ext/lwip-contrib
-	url = https://git.savannah.nongnu.org/git/lwip/lwip-contrib.git
 [submodule "ext/ZeroTierOne"]
 	path = ext/ZeroTierOne
 	url = https://github.com/zerotier/ZeroTierOne.git
diff --git a/ext/lwip b/ext/lwip
deleted file mode 160000
index 159e31b..0000000
--- a/ext/lwip
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 159e31b689577dbf69cf0683bbaffbd71fa5ee10
diff --git a/ext/lwip-contrib b/ext/lwip-contrib
deleted file mode 160000
index 35b011d..0000000
--- a/ext/lwip-contrib
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 35b011d4cf4c4b480f8859c456587a884ec9d287