diff --git a/.gitmodules b/.gitmodules
deleted file mode 100644
index 0fd9eca03999..000000000000
--- a/.gitmodules
+++ /dev/null
@@ -1,3 +0,0 @@
-[submodule "safe_duration_cast"]
-	path = safe_duration_cast
-	url = https://github.com/pauldreik/safe_duration_cast.git
diff --git a/safe_duration_cast b/safe_duration_cast
deleted file mode 160000
index 9309beb24b65..000000000000
--- a/safe_duration_cast
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 9309beb24b65f10860f0045635ac27d031b4e9a9