diff --git a/12.nix b/12.nix
new file mode 100644
index 0000000..8848e97
--- /dev/null
+++ b/12.nix
@@ -0,0 +1,14 @@
+let
+  b = 1;
+  fu0 = (x: x);
+  fu1 = (x: y: x + y) 4;
+  fu2 = (x: y: (2 * x) + y);
+in
+rec {
+  ex00 = fu0 4;     # must return 4
+  ex01 = (fu1) 1;   # must return 5
+  ex02 = (fu2 3 ) 1; # must return 7
+  ex03 = (fu2 3 );   # must return <LAMBDA>
+  ex04 = ex03 1;    # must return 7
+  ex05 = (n: x: (fu2 x n)) 1 3; # must return 7
+}
\ No newline at end of file