diff --git a/24.nix b/24.nix
new file mode 100644
index 0000000..438315d
--- /dev/null
+++ b/24.nix
@@ -0,0 +1,16 @@
+with import <nixpkgs> {};
+with lib;
+{
+  ex00 = isAttrs {};
+  ex01 = isAttrs {};
+  ex02 = isString "a"; 
+  ex03 = isInt (-3); 
+  ex04 = isFunction (x: x);
+  ex05 = isString (x:x);
+  ex06 = isString ("x");
+  ex07 = isNull null; 
+  ex08 = isFunction (y: y+1);
+  ex09 = isList [({z}: z) (x: x)];
+  ex10 = isAttrs {a=[];};
+  ex11 = isInt (-10); # oh, what is that?
+}
\ No newline at end of file