diff --git a/asm/assemble.go b/asm/assemble.go
index ae83928..ec9bd8f 100644
--- a/asm/assemble.go
+++ b/asm/assemble.go
@@ -7,20 +7,6 @@ import "strings"
 import "github.com/firestuff/subcoding/vm"
 import "github.com/pkg/errors"
 
-var opCodeByName = map[string]vm.OpCodeType{
-	"add":  vm.OpAdd,
-	"call": vm.OpCall,
-	"ltu":  vm.OpLTU,
-	"jmpt": vm.OpJmpT,
-}
-
-var operandsByOpCode = map[vm.OpCodeType]int{
-	vm.OpAdd:  2,
-	vm.OpCall: 1,
-	vm.OpLTU:  2,
-	vm.OpJmpT: 1,
-}
-
 func Assemble(src []byte) ([][]*vm.Instruction, error) {
 	prog, err := parse(src)
 	if err != nil {
@@ -67,7 +53,7 @@ func assembleInstruction(in instruction) (*vm.Instruction, error) {
 
 	instr := &vm.Instruction{}
 
-	opCode, found := opCodeByName[in[0]]
+	opCode, found := opCodeByName[strings.ToLower(in[0])]
 	if !found {
 		return nil, fmt.Errorf("Invalid op name: %s\n", in[0])
 	}
@@ -101,6 +87,7 @@ func assembleInstruction(in instruction) (*vm.Instruction, error) {
 }
 
 func assembleOperand(op string) (vm.Operand, error) {
+	op = strings.ToLower(op)
 	ret := vm.Operand{}
 	numStr := ""
 
diff --git a/asm/opcodes.go b/asm/opcodes.go
new file mode 100644
index 0000000..46c8be8
--- /dev/null
+++ b/asm/opcodes.go
@@ -0,0 +1,78 @@
+package asm
+
+import "github.com/firestuff/subcoding/vm"
+
+var opCodeByName = map[string]vm.OpCodeType{
+	"noop":   vm.OpNoOp,
+	"nop":    vm.OpNop,
+	"call":   vm.OpCall,
+	"cal":    vm.OpCal,
+	"return": vm.OpReturn,
+	"ret":    vm.OpRet,
+
+	"move": vm.OpMove,
+	"mov":  vm.OpMov,
+
+	"add":            vm.OpAdd,
+	"subtract":       vm.OpSubtract,
+	"sub":            vm.OpSub,
+	"multiply":       vm.OpMultiply,
+	"mul":            vm.OpMul,
+	"divideunsigned": vm.OpDivideUnsigned,
+	"divu":           vm.OpDivU,
+	"dividesigned":   vm.OpDivideSigned,
+	"divs":           vm.OpDivS,
+
+	"isequal":                      vm.OpIsEqual,
+	"eq":                           vm.OpEq,
+	"islessthanunsigned":           vm.OpIsLessThanUnsigned,
+	"ltu":                          vm.OpLTU,
+	"islessthansigned":             vm.OpIsLessThanSigned,
+	"lts":                          vm.OpLTS,
+	"isgreaterthanunsigned":        vm.OpIsGreaterThanUnsigned,
+	"gtu":                          vm.OpGTU,
+	"isgreaterthansigned":          vm.OpIsGreaterThanSigned,
+	"gts":                          vm.OpGTS,
+	"islessthanorequalunsigned":    vm.OpIsLessThanOrEqualUnsigned,
+	"lteu":                         vm.OpLTEU,
+	"islessthanorequalsigned":      vm.OpIsLessThanOrEqualSigned,
+	"ltes":                         vm.OpLTES,
+	"isgreaterthanorequalunsigned": vm.OpIsGreaterThanOrEqualUnsigned,
+	"gteu":                         vm.OpGTEU,
+	"isgreaterthanorequalsigned":   vm.OpIsGreaterThanOrEqualSigned,
+	"gtes":                         vm.OpGTES,
+
+	"jump":        vm.OpJump,
+	"jmp":         vm.OpJmp,
+	"jumpiftrue":  vm.OpJumpIfTrue,
+	"jmpt":        vm.OpJmpT,
+	"jumpiffalse": vm.OpJumpIfFalse,
+	"jmpf":        vm.OpJmpF,
+}
+
+var operandsByOpCode = map[vm.OpCodeType]int{
+	vm.OpNop: 0,
+	vm.OpCal: 1,
+	vm.OpRet: 0,
+
+	vm.OpMov:  2,
+	vm.OpAdd:  2,
+	vm.OpSub:  2,
+	vm.OpMul:  2,
+	vm.OpDivU: 2,
+	vm.OpDivS: 2,
+
+	vm.OpEq:   2,
+	vm.OpLTU:  2,
+	vm.OpLTS:  2,
+	vm.OpGTU:  2,
+	vm.OpGTS:  2,
+	vm.OpLTEU: 2,
+	vm.OpLTES: 2,
+	vm.OpGTEU: 2,
+	vm.OpGTES: 2,
+
+	vm.OpJmp:  1,
+	vm.OpJmpT: 1,
+	vm.OpJmpF: 1,
+}