diff --git a/wharrgarbl-strobe/src/lib.rs b/wharrgarbl-strobe/src/lib.rs
index 6108fca..cd4f461 100644
--- a/wharrgarbl-strobe/src/lib.rs
+++ b/wharrgarbl-strobe/src/lib.rs
@@ -1,3 +1,6 @@
+#![no_std]
+#![forbid(unsafe_code)]
+
 mod keccakf;
 mod opflags;
 mod ops;
diff --git a/wharrgarbl-utils/src/lib.rs b/wharrgarbl-utils/src/lib.rs
index 962f969..cb0a330 100644
--- a/wharrgarbl-utils/src/lib.rs
+++ b/wharrgarbl-utils/src/lib.rs
@@ -1,4 +1,5 @@
 #![no_std]
+#![forbid(unsafe_code)]
 
 #[derive(Debug)]
 pub struct BufferSlice<'slice> {