diff --git a/extra/random-tester/random/random.factor b/extra/random-tester/random/random.factor
index da9a5c26d8..7cd669becf 100755
--- a/extra/random-tester/random/random.factor
+++ b/extra/random-tester/random/random.factor
@@ -1,22 +1,12 @@
-USING: kernel math sequences namespaces errors hashtables words
-arrays parser compiler syntax io tools prettyprint optimizer
-inference ;
+USING: kernel math sequences namespaces hashtables words
+arrays parser compiler syntax io prettyprint optimizer
+random math.constants math.functions layouts random-tester.utils ;
 IN: random-tester
 
 ! Tweak me
 : max-length 15 ; inline
 : max-value 1000000000 ; inline
 
-: 10% ( -- bool ) 10 random 8 > ;
-: 20% ( -- bool ) 10 random 7 > ;
-: 30% ( -- bool ) 10 random 6 > ;
-: 40% ( -- bool ) 10 random 5 > ;
-: 50% ( -- bool ) 10 random 4 > ;
-: 60% ( -- bool ) 10 random 3 > ;
-: 70% ( -- bool ) 10 random 2 > ;
-: 80% ( -- bool ) 10 random 1 > ;
-: 90% ( -- bool ) 10 random 0 > ;
-
 ! varying bit-length random number
 : random-bits ( n -- int )
     random 2 swap ^ random ;
@@ -31,32 +21,29 @@ IN: random-tester
 SYMBOL: special-integers
 [ { -1 0 1 } % most-negative-fixnum , most-positive-fixnum , first-bignum , ] 
 { } make \ special-integers set-global
-: special-integers ( -- seq ) \ special-integers get ;
 SYMBOL: special-floats
 [ { 0.0 -0.0 } % e , pi , 1./0. , -1./0. , 0./0. , epsilon , epsilon neg , ]
 { } make \ special-floats set-global
-: special-floats ( -- seq ) \ special-floats get ;
 SYMBOL: special-complexes
 [ 
-    { -1 0 1 i -i } %
+    { -1 0 1 C{ 0 1 } C{ 0 -1 } } %
     e , e neg , pi , pi neg ,
     0 pi rect> , 0 pi neg rect> , pi neg 0 rect> , pi pi rect> ,
     pi pi neg rect> , pi neg pi rect> , pi neg pi neg rect> ,
     e neg e neg rect> , e e rect> ,
 ] { } make \ special-complexes set-global
-: special-complexes ( -- seq ) \ special-complexes get ;
 
 : random-fixnum ( -- fixnum )
-    most-positive-fixnum random 1+ coin-flip [ neg 1- ] when >fixnum ;
+    most-positive-fixnum random 1+ 50% [ neg 1- ] when >fixnum ;
 
 : random-bignum ( -- bignum )
-     400 random-bits first-bignum + coin-flip [ neg ] when ;
+     400 random-bits first-bignum + 50% [ neg ] when ;
     
 : random-integer ( -- n )
-    coin-flip [
+    50% [
         random-fixnum
     ] [
-        coin-flip [ random-bignum ] [ special-integers random ] if
+        50% [ random-bignum ] [ special-integers get random ] if
     ] if ;
 
 : random-positive-integer ( -- int )
@@ -67,12 +54,12 @@ SYMBOL: special-complexes
     ] if ;
 
 : random-ratio ( -- ratio )
-    1000000000 dup [ random ] 2apply 1+ / coin-flip [ neg ] when dup [ drop random-ratio ] unless 10% [ drop 0 ] when ;
+    1000000000 dup [ random ] 2apply 1+ / 50% [ neg ] when dup [ drop random-ratio ] unless 10% [ drop 0 ] when ;
 
 : random-float ( -- float )
-    coin-flip [ random-ratio ] [ special-floats random ] if
-    coin-flip 
-    [ .0000000000000000001 /f ] [ coin-flip [ .00000000000000001 * ] when ] if
+    50% [ random-ratio ] [ special-floats get random ] if
+    50%
+    [ .0000000000000000001 /f ] [ 50% [ .00000000000000001 * ] when ] if
     >float ;
 
 : random-number ( -- number )