diff --git a/creature_test.go b/creature_test.go
index 20f3940..a7055f9 100644
--- a/creature_test.go
+++ b/creature_test.go
@@ -2,12 +2,8 @@ package creature
 
 import "testing"
 
-func TestPush(test *testing.T) {
-	machine := Machine {
-		Program: []int {
-			0x0, 654,
-		},
-	}
+func runMachineTest(program []int, test *testing.T) (machine *Machine) {
+	machine = &Machine { Program: program }
 
 	err := machine.Execute(0)
 	if err != nil {
@@ -15,6 +11,14 @@ func TestPush(test *testing.T) {
 		test.Fail()
 	}
 
+	return
+}
+
+func TestPush(test *testing.T) {
+	machine := runMachineTest ([]int {
+		0x0, 654,
+	}, test)
+	
 	result := machine.Pop()
 	test.Log("popped:", result)
 
@@ -25,31 +29,23 @@ func TestPush(test *testing.T) {
 }
 
 func TestArithmetic(test *testing.T) {
-	machine := Machine {
-		Program: []int {
-			0x0, 2,
-			0x0, 3,
-			0x4,
-			
-			0x0, 10,
-			0x0, 4,
-			0x5,
-			
-			0x0, 7,
-			0x0, 2,
-			0x6,
-			
-			0x0, 12,
-			0x0, 3,
-			0x7,
-		},
-	}
-
-	err := machine.Execute(0)
-	if err != nil {
-		test.Log("machine exited with error:", err)
-		test.Fail()
-	}
+	machine := runMachineTest([]int {
+		0x0, 2,
+		0x0, 3,
+		0x4,
+		
+		0x0, 10,
+		0x0, 4,
+		0x5,
+		
+		0x0, 7,
+		0x0, 2,
+		0x6,
+		
+		0x0, 12,
+		0x0, 3,
+		0x7,
+	}, test)
 
 	addResult := machine.Pop()
 	subResult := machine.Pop()