diff --git a/x11/src/lib.rs b/x11/src/lib.rs
index a2cf2bd..aa1e7e0 100644
--- a/x11/src/lib.rs
+++ b/x11/src/lib.rs
@@ -1,3 +1,4 @@
+#[forbid(unsafe_code)]
 mod clipboard;
 mod error;