diff --git a/lib/compiler/scope_analysis.ml b/lib/compiler/scope_analysis.ml
index 7b59bf1..b3cc8a0 100644
--- a/lib/compiler/scope_analysis.ml
+++ b/lib/compiler/scope_analysis.ml
@@ -59,7 +59,8 @@ let default_global_table =
   SymbolTable.of_list [
       ("PRINT", (0, Native 0));
       ("+", (1, Native 1));
-      ("-", (2, Native 2))
+      ("-", (2, Native 2));
+      ("*", (3, Native 3))
     ]
 
 (* extract all defined global symbols, given the top-level expressions
diff --git a/lib/vm/native.ml b/lib/vm/native.ml
index 9072e71..a4d6297 100644
--- a/lib/vm/native.ml
+++ b/lib/vm/native.ml
@@ -16,20 +16,18 @@ let to_numeric = function
 let of_numeric = function
   | NInt x -> Int x
   | NDouble x -> Double x
-let numeric_add = function
+
+let numeric_generic fi fd = function
   | NInt x -> (function
-               | NInt y -> NInt (x+y)
-               | NDouble y -> NDouble ((float_of_int x) +. y))
+               | NInt y -> NInt (fi x y)
+               | NDouble y -> NDouble (fd (float_of_int x) y))
   | NDouble x -> (function
-                  | NInt y -> NDouble (x+.(float_of_int y))
-                  | NDouble y -> NDouble (x+.y))
-let numeric_sub = function
-  | NInt x -> (function
-               | NInt y -> NInt (x - y)
-               | NDouble y -> NDouble ((float_of_int x) -. y))
-  | NDouble x -> (function
-                  | NInt y -> NDouble (x-.(float_of_int y))
-                  | NDouble y -> NDouble (x-.y))
+                  | NInt y -> NDouble (fd x (float_of_int y))
+                  | NDouble y -> NDouble (fd x y)) 
+let numeric_add = numeric_generic (+) (+.)
+let numeric_sub = numeric_generic (-) (-.)
+let numeric_mul = numeric_generic ( * ) ( *. )
+let numeric_div = numeric_generic ( / ) ( /. )
 
 let builtin_print (v : Types.value ref list) =
   List.iter (fun r -> print_endline (print_value !r)) v;
@@ -39,14 +37,22 @@ let builtin_add (vs : Types.value ref list) =
   of_numeric (List.fold_left numeric_add (NInt 0) (List.map (fun r -> to_numeric !r) vs))
 let builtin_sub (vs : Types.value ref list) =
   match vs with
+  | f :: [] -> of_numeric (match (to_numeric !f) with
+               | NInt x -> NInt (Int.neg x)
+               | NDouble x -> NDouble (Float.neg x))
   | f :: rest -> of_numeric (List.fold_left numeric_sub (to_numeric !f) (List.map (fun r -> to_numeric !r) rest))
   | [] -> failwith "invalid number of arguments for subtraction"
 
+let builtin_mul vs =
+  of_numeric (List.fold_left numeric_mul (NInt 1) (List.map (fun r -> to_numeric !r) vs))
+
+
 
 let table = [|
     builtin_print;
     builtin_add;
-    builtin_sub
+    builtin_sub;
+    builtin_mul
   |]