diff --git a/test/test_crypto.ml b/test/test_crypto.ml
index 28c1e780..c26481f3 100644
--- a/test/test_crypto.ml
+++ b/test/test_crypto.ml
@@ -108,3 +108,16 @@ let () =
   assert (encode bmsg = blinded_message);
 
   ()
+
+let () = Mirage_crypto_rng_unix.use_default ()
+
+let () =
+  let open Crypto in
+  let priv, pub = RsaPrivateKey.generate ~bits:2048 () in
+  let bks = "deadbeaf" in
+  let msg = "uhuh." in
+  let sig_ = Fdh_rsa.sign ~priv ~pub ~bks ~msg in
+  let res = Fdh_rsa.verify pub ~msg ~sig_ in
+  assert (Result.is_ok res);
+
+  ()