diff --git a/pkgs/by-name/ws/wslay/package.nix b/pkgs/by-name/ws/wslay/package.nix
index e9111bbb7a3e..ed6c0c9b6735 100644
--- a/pkgs/by-name/ws/wslay/package.nix
+++ b/pkgs/by-name/ws/wslay/package.nix
@@ -11,11 +11,18 @@ stdenv.mkDerivation rec {
     hash = "sha256-xKQGZO5hNzMg+JYKeqOBsu73YO+ucBEOcNhG8iSNYvA=";
   };
 
-  checkInputs = [ cunit ];
-  doCheck = true;
+  strictDeps = true;
 
   nativeBuildInputs = [ cmake ];
 
+  cmakeFlags = [
+    (lib.cmakeBool "WSLAY_TESTS" true)
+  ];
+
+  doCheck = true;
+
+  checkInputs = [ cunit ];
+
   meta = with lib; {
     homepage = "https://tatsuhiro-t.github.io/wslay/";
     description = "The WebSocket library in C";