diff --git a/src/core/Evaluate.go b/src/core/Evaluate.go
index 216e480..81ffac0 100644
--- a/src/core/Evaluate.go
+++ b/src/core/Evaluate.go
@@ -27,8 +27,14 @@ func (f *Function) Evaluate(expr *expression.Expression) (ssa.Value, error) {
 				}
 
 				f.Dependencies.Add(function)
-				v := f.AppendFunction(function.UniqueName, function.Type, function.IsExtern())
-				v.SetSource(expr.Source)
+
+				v := f.Append(&ssa.Function{
+					UniqueName: function.UniqueName,
+					Typ:        function.Type,
+					IsExtern:   function.IsExtern(),
+					Source:     ssa.Source(expr.Source),
+				})
+
 				return v, nil
 			}
 
@@ -41,26 +47,33 @@ func (f *Function) Evaluate(expr *expression.Expression) (ssa.Value, error) {
 				return nil, err
 			}
 
-			v := f.AppendInt(number)
-			v.SetSource(expr.Source)
+			v := f.Append(&ssa.Int{
+				Int:    number,
+				Source: ssa.Source(expr.Source),
+			})
+
 			return v, nil
 
 		case token.String:
 			data := expr.Token.Bytes(f.File.Bytes)
 			data = Unescape(data)
 
-			length := f.AppendInt(len(data))
-			length.SetSource(expr.Source)
+			length := f.Append(&ssa.Int{
+				Int:    len(data),
+				Source: ssa.Source(expr.Source),
+			})
 
-			pointer := f.AppendBytes(data)
-			pointer.SetSource(expr.Source)
+			pointer := f.Append(&ssa.Bytes{
+				Bytes:  data,
+				Source: ssa.Source(expr.Source),
+			})
 
 			v := f.Append(&ssa.Struct{
 				Arguments: []ssa.Value{pointer, length},
 				Typ:       types.String,
+				Source:    ssa.Source(expr.Source),
 			})
 
-			v.SetSource(expr.Source)
 			return v, nil
 		}
 
@@ -75,17 +88,6 @@ func (f *Function) Evaluate(expr *expression.Expression) (ssa.Value, error) {
 		if children[0].Token.Kind == token.Identifier {
 			funcName := children[0].String(f.File.Bytes)
 
-			if funcName == "len" {
-				identifier := children[1].String(f.File.Bytes)
-				length, exists := f.Identifiers[identifier+".len"]
-
-				if !exists {
-					return nil, errors.New(&UnknownIdentifier{Name: identifier + ".len"}, f.File, expr.Token.Position)
-				}
-
-				return length, nil
-			}
-
 			if funcName == "syscall" {
 				children = children[1:]
 				isSyscall = true
@@ -111,47 +113,57 @@ func (f *Function) Evaluate(expr *expression.Expression) (ssa.Value, error) {
 			}
 
 			return f.Append(syscall), nil
-		} else {
-			name := args[0].(*ssa.Function).UniqueName
-			fn := f.All.Functions[name]
-			parameters := args[1:]
+		}
 
-			if len(parameters) != len(fn.Input) {
-				return nil, errors.New(&ParameterCountMismatch{Function: name, Count: len(parameters), ExpectedCount: len(fn.Input)}, f.File, expr.Source[0].Position)
-			}
+		name := args[0].(*ssa.Function).UniqueName
+		fn := f.All.Functions[name]
+		parameters := args[1:]
 
-			for i, param := range slices.Backward(parameters) {
-				if !types.Is(param.Type(), fn.Input[i].Typ) {
-					_, isPointer := fn.Input[i].Typ.(*types.Pointer)
+		if len(parameters) != len(fn.Input) {
+			return nil, errors.New(&ParameterCountMismatch{Function: name, Count: len(parameters), ExpectedCount: len(fn.Input)}, f.File, expr.Source[0].Position)
+		}
 
-					if isPointer {
-						number, isInt := param.(*ssa.Int)
+		for i, param := range slices.Backward(parameters) {
+			if !types.Is(param.Type(), fn.Input[i].Typ) {
+				_, isPointer := fn.Input[i].Typ.(*types.Pointer)
 
-						if isInt && number.Int == 0 {
-							continue
-						}
-					}
+				if isPointer {
+					number, isInt := param.(*ssa.Int)
 
-					// Temporary hack to allow int64 -> uint32 conversion
-					if types.Is(param.Type(), types.AnyInt) && types.Is(fn.Input[i].Typ, types.AnyInt) {
+					if isInt && number.Int == 0 {
 						continue
 					}
-
-					return nil, errors.New(&TypeMismatch{
-						Encountered:   param.Type().Name(),
-						Expected:      fn.Input[i].Typ.Name(),
-						ParameterName: fn.Input[i].Name,
-					}, f.File, param.Start())
 				}
-			}
 
-			if fn.IsExtern() {
-				return f.Append(&ssa.CallExtern{Arguments: args, Source: ssa.Source(expr.Source)}), nil
-			}
+				// Temporary hack to allow int64 -> uint32 conversion
+				if types.Is(param.Type(), types.AnyInt) && types.Is(fn.Input[i].Typ, types.AnyInt) {
+					continue
+				}
 
-			return f.Append(&ssa.Call{Arguments: args, Source: ssa.Source(expr.Source)}), nil
+				return nil, errors.New(&TypeMismatch{
+					Encountered:   param.Type().Name(),
+					Expected:      fn.Input[i].Typ.Name(),
+					ParameterName: fn.Input[i].Name,
+				}, f.File, param.Start())
+			}
 		}
 
+		if fn.IsExtern() {
+			v := f.Append(&ssa.CallExtern{
+				Arguments: args,
+				Source:    ssa.Source(expr.Source),
+			})
+
+			return v, nil
+		}
+
+		v := f.Append(&ssa.Call{
+			Arguments: args,
+			Source:    ssa.Source(expr.Source),
+		})
+
+		return v, nil
+
 	case token.Dot:
 		left := expr.Children[0]
 		right := expr.Children[1]
@@ -167,8 +179,12 @@ func (f *Function) Evaluate(expr *expression.Expression) (ssa.Value, error) {
 				return nil, errors.New(&UnknownStructField{StructName: structure.Name(), FieldName: rightText}, f.File, right.Token.Position)
 			}
 
-			v := f.Append(&ssa.StructField{Struct: identifier, Field: field})
-			v.SetSource(expr.Source)
+			v := f.Append(&ssa.StructField{
+				Struct: identifier,
+				Field:  field,
+				Source: ssa.Source(expr.Source),
+			})
+
 			return v, nil
 		}
 
@@ -182,13 +198,19 @@ func (f *Function) Evaluate(expr *expression.Expression) (ssa.Value, error) {
 				f.Dependencies.Add(function)
 			}
 
-			v := f.AppendFunction(function.UniqueName, function.Type, function.IsExtern())
-			v.SetSource(expr.Source)
+			v := f.Append(&ssa.Function{
+				UniqueName: function.UniqueName,
+				Typ:        function.Type,
+				IsExtern:   function.IsExtern(),
+				Source:     ssa.Source(expr.Source),
+			})
+
 			return v, nil
 		}
 
 		return nil, errors.New(&UnknownIdentifier{Name: label}, f.File, left.Token.Position)
-	}
 
-	return nil, nil
+	default:
+		panic("not implemented")
+	}
 }
\ No newline at end of file
diff --git a/src/ssa/BinaryOp_test.go b/src/ssa/BinaryOp_test.go
index 5994058..2eab37e 100644
--- a/src/ssa/BinaryOp_test.go
+++ b/src/ssa/BinaryOp_test.go
@@ -11,12 +11,12 @@ import (
 
 func TestBinaryOp(t *testing.T) {
 	fn := ssa.IR{}
-	a := fn.AppendInt(1)
-	b := fn.AppendInt(2)
+	a := fn.Append(&ssa.Int{Int: 1})
+	b := fn.Append(&ssa.Int{Int: 2})
 	c := fn.Append(&ssa.BinaryOp{Op: token.Add, Left: a, Right: b})
 	fn.AddBlock()
-	d := fn.AppendInt(3)
-	e := fn.AppendInt(4)
+	d := fn.Append(&ssa.Int{Int: 3})
+	e := fn.Append(&ssa.Int{Int: 4})
 	f := fn.Append(&ssa.BinaryOp{Op: token.Add, Left: d, Right: e})
 
 	assert.Equal(t, c.String(), "1 + 2")
@@ -26,11 +26,11 @@ func TestBinaryOp(t *testing.T) {
 
 func TestBinaryOpEquals(t *testing.T) {
 	fn := ssa.IR{}
-	one := fn.AppendInt(1)
-	two := fn.AppendInt(2)
+	one := fn.Append(&ssa.Int{Int: 1})
+	two := fn.Append(&ssa.Int{Int: 2})
 	binOp := fn.Append(&ssa.BinaryOp{Op: token.Add, Left: one, Right: two})
-	oneDup := fn.AppendInt(1)
-	twoDup := fn.AppendInt(2)
+	oneDup := fn.Append(&ssa.Int{Int: 1})
+	twoDup := fn.Append(&ssa.Int{Int: 2})
 	binOpDup := fn.Append(&ssa.BinaryOp{Op: token.Add, Left: oneDup, Right: twoDup})
 	binOpDiff := fn.Append(&ssa.BinaryOp{Op: token.Add, Left: oneDup, Right: oneDup})
 
diff --git a/src/ssa/Bytes_test.go b/src/ssa/Bytes_test.go
index eee39a1..941927a 100644
--- a/src/ssa/Bytes_test.go
+++ b/src/ssa/Bytes_test.go
@@ -13,7 +13,7 @@ func TestBytes(t *testing.T) {
 	hello := fn.Append(&ssa.Bytes{Bytes: []byte("Hello")})
 	world := fn.Append(&ssa.Bytes{Bytes: []byte("World")})
 	helloDup := fn.Append(&ssa.Bytes{Bytes: []byte("Hello")})
-	one := fn.AppendInt(1)
+	one := fn.Append(&ssa.Int{Int: 1})
 
 	assert.False(t, hello.Equals(world))
 	assert.False(t, hello.Equals(one))
diff --git a/src/ssa/Call_test.go b/src/ssa/Call_test.go
index 756e540..e77cff6 100644
--- a/src/ssa/Call_test.go
+++ b/src/ssa/Call_test.go
@@ -12,7 +12,7 @@ func TestCall(t *testing.T) {
 	fn := ssa.IR{}
 	myfunc := fn.Append(&ssa.Function{UniqueName: "myfunc", Typ: &types.Function{}})
 	call := fn.Append(&ssa.Call{Arguments: ssa.Arguments{myfunc}})
-	one := fn.AppendInt(1)
+	one := fn.Append(&ssa.Int{Int: 1})
 	call2 := fn.Append(&ssa.Call{Arguments: ssa.Arguments{myfunc, one}})
 
 	assert.True(t, call.Type() == types.Void)
@@ -31,8 +31,8 @@ func TestCallEquals(t *testing.T) {
 		},
 	})
 
-	one := fn.AppendInt(1)
-	two := fn.AppendInt(2)
+	one := fn.Append(&ssa.Int{Int: 1})
+	two := fn.Append(&ssa.Int{Int: 2})
 	call1 := fn.Append(&ssa.Call{Arguments: ssa.Arguments{sum, one, two}})
 	call2 := fn.Append(&ssa.Call{Arguments: ssa.Arguments{sum, one, two}})
 
@@ -51,8 +51,8 @@ func TestCallReturnType(t *testing.T) {
 		},
 	})
 
-	one := fn.AppendInt(1)
-	two := fn.AppendInt(2)
+	one := fn.Append(&ssa.Int{Int: 1})
+	two := fn.Append(&ssa.Int{Int: 2})
 	call := fn.Append(&ssa.Call{Arguments: ssa.Arguments{sum, one, two}})
 
 	assert.Equal(t, call.String(), "sum(1, 2)")
diff --git a/src/ssa/IR.go b/src/ssa/IR.go
index c2022d2..fea735d 100644
--- a/src/ssa/IR.go
+++ b/src/ssa/IR.go
@@ -1,9 +1,5 @@
 package ssa
 
-import (
-	"git.urbach.dev/cli/q/src/types"
-)
-
 // IR is a list of basic blocks.
 type IR struct {
 	Blocks []*Block
@@ -26,12 +22,10 @@ func (f *IR) Append(instr Value) Value {
 		f.AddBlock()
 	}
 
-	if instr.IsConst() {
-		for existing := range f.Values {
-			if existing.IsConst() && instr.Equals(existing) {
-				return existing
-			}
-		}
+	existing := f.FindExisting(instr)
+
+	if existing != nil {
+		return existing
 	}
 
 	instr.SetID(f.nextId)
@@ -39,24 +33,19 @@ func (f *IR) Append(instr Value) Value {
 	return f.Blocks[len(f.Blocks)-1].Append(instr)
 }
 
-// AppendInt adds a new integer value to the last block.
-func (f *IR) AppendInt(x int) Value {
-	return f.Append(&Int{Int: x})
-}
+// FindExisting returns an equal instruction that's already appended or `nil` if none could be found.
+func (f *IR) FindExisting(instr Value) Value {
+	if !instr.IsConst() {
+		return nil
+	}
 
-// AppendFunction adds a new function value to the last block.
-func (f *IR) AppendFunction(name string, typ *types.Function, extern bool) Value {
-	return f.Append(&Function{UniqueName: name, Typ: typ, IsExtern: extern})
-}
+	for existing := range f.Values {
+		if existing.IsConst() && instr.Equals(existing) {
+			return existing
+		}
+	}
 
-// AppendBytes adds a new byte slice value to the last block.
-func (f *IR) AppendBytes(s []byte) Value {
-	return f.Append(&Bytes{Bytes: s})
-}
-
-// AppendString adds a new string value to the last block.
-func (f *IR) AppendString(s string) Value {
-	return f.Append(&Bytes{Bytes: []byte(s)})
+	return nil
 }
 
 // Values yields on each value.
diff --git a/src/ssa/Int.go b/src/ssa/Int.go
index e07603c..0488f51 100644
--- a/src/ssa/Int.go
+++ b/src/ssa/Int.go
@@ -1,7 +1,7 @@
 package ssa
 
 import (
-	"fmt"
+	"strconv"
 
 	"git.urbach.dev/cli/q/src/types"
 )
@@ -36,7 +36,7 @@ func (v *Int) Debug(expand bool) string {
 }
 
 func (v *Int) String() string {
-	return fmt.Sprintf("%d", v.Int)
+	return strconv.Itoa(v.Int)
 }
 
 func (v *Int) Type() types.Type {
diff --git a/src/ssa/Return_test.go b/src/ssa/Return_test.go
index a789f83..3df47c8 100644
--- a/src/ssa/Return_test.go
+++ b/src/ssa/Return_test.go
@@ -11,9 +11,9 @@ import (
 func TestReturn(t *testing.T) {
 	fn := ssa.IR{}
 	ret := fn.Append(&ssa.Return{})
-	one := fn.AppendInt(1)
+	one := fn.Append(&ssa.Int{Int: 1})
 	ret2 := fn.Append(&ssa.Return{Arguments: ssa.Arguments{one}})
-	two := fn.AppendInt(2)
+	two := fn.Append(&ssa.Int{Int: 2})
 	ret3 := fn.Append(&ssa.Return{Arguments: ssa.Arguments{one, two}})
 	ret4 := fn.Append(&ssa.Return{Arguments: ssa.Arguments{two, one}})
 	ret5 := fn.Append(&ssa.Return{Arguments: ssa.Arguments{one, two}})
diff --git a/src/ssa/Syscall_test.go b/src/ssa/Syscall_test.go
index 63dab89..1f3bdb8 100644
--- a/src/ssa/Syscall_test.go
+++ b/src/ssa/Syscall_test.go
@@ -11,9 +11,9 @@ import (
 func TestSyscall(t *testing.T) {
 	fn := ssa.IR{}
 	syscall := fn.Append(&ssa.Syscall{})
-	one := fn.AppendInt(1)
+	one := fn.Append(&ssa.Int{Int: 1})
 	syscall2 := fn.Append(&ssa.Syscall{Arguments: ssa.Arguments{one}})
-	two := fn.AppendInt(2)
+	two := fn.Append(&ssa.Int{Int: 2})
 	syscall3 := fn.Append(&ssa.Syscall{Arguments: ssa.Arguments{one, two}})
 	syscall4 := fn.Append(&ssa.Syscall{Arguments: ssa.Arguments{one, two}})