diff --git a/expr/build.go b/expr/build.go
new file mode 100644
index 0000000..92a08a7
--- /dev/null
+++ b/expr/build.go
@@ -0,0 +1,28 @@
+package expr
+
+import "llvm.org/llvm/bindings/go/llvm"
+
+type LLVMCtx struct {
+	B llvm.Builder
+	M llvm.Module
+}
+
+func Build(ctx *Ctx, lctx LLVMCtx, stmts []Expr) {
+	for _, stmt := range stmts {
+		BuildStmt(ctx, lctx, stmt)
+	}
+}
+
+func BuildStmt(ctx *Ctx, lctx LLVMCtx, stmtE Expr) {
+	s := stmtE.Actual.(Statement)
+	m := s.Op.Actual.(Macro)
+
+	fn := ctx.GetMacro(m)
+	if fn == nil {
+		panicf("unknown macro: %q", m)
+	}
+	lv, ok := fn(ctx, lctx, s.Arg)
+	if ok {
+		ctx.LastVal = lv
+	}
+}
diff --git a/expr/ctx.go b/expr/ctx.go
index 67592a8..ac5ae14 100644
--- a/expr/ctx.go
+++ b/expr/ctx.go
@@ -1,17 +1,23 @@
 package expr
 
+import "llvm.org/llvm/bindings/go/llvm"
+
+type MacroFn func(*Ctx, LLVMCtx, Expr) (llvm.Value, bool)
+
 // Ctx contains all the Macros and Identifiers available. A Ctx is based on the
 // parent it was created from. If the current Ctx doesn't have a particular key
 // being looked up, the parent is called instead, and so on. A consequence of
 // this is that keys in the children take precedence over the parent's
 type Ctx struct {
 	Parent *Ctx
-	Macros map[Macro]func(Expr) (Expr, error)
+	Macros map[Macro]MacroFn
+
+	LastVal llvm.Value
 }
 
 // GetMacro returns the first instance of the given of the given Macro found. If
 // not found nil is returned.
-func (c *Ctx) GetMacro(m Macro) func(Expr) (Expr, error) {
+func (c *Ctx) GetMacro(m Macro) MacroFn {
 	if c.Macros != nil {
 		if fn, ok := c.Macros[m]; ok {
 			return fn
diff --git a/expr/expr.go b/expr/expr.go
index 42ee4dc..84f4e53 100644
--- a/expr/expr.go
+++ b/expr/expr.go
@@ -2,7 +2,6 @@ package expr
 
 import (
 	"fmt"
-	"strings"
 
 	"llvm.org/llvm/bindings/go/llvm"
 
@@ -13,25 +12,11 @@ import (
 // TODO empty parenthesis
 // TODO need to figure out how to test LLVMVal stuff
 // TODO once we're a bit more confident, make ActualFunc
-// TODO LLVMVal -> LLVMBuild?
 
-type LLVMCtx struct {
-	B llvm.Builder
-	M llvm.Module
-}
-
-// Actual represents the actual expression in question, and has certain
-// properties. It is wrapped by Expr which also holds onto contextual
-// information, like the token to which Actual was originally parsed from
+// Actual represents the actual expression in question. It is wrapped by Expr
+// which also holds onto contextual information, like the token to which Actual
+// was originally parsed from
 type Actual interface {
-	// Returns the llvm.Type which the expression accepts as an input, if any
-	LLVMInType(ctx *Ctx) llvm.Type
-
-	// Returns the llvm.Type which the expressions outputs
-	LLVMOutType(ctx *Ctx) llvm.Type
-
-	// Initializes an llvm.Value and returns it.
-	LLVMVal(*Ctx, LLVMCtx) llvm.Value
 }
 
 // equaler is used to compare two expressions. The comparison should not take
@@ -52,27 +37,6 @@ type Expr struct {
 	val *llvm.Value
 }
 
-// LLVMInType passes through to the method on the underlying Actual
-func (e Expr) LLVMInType(ctx *Ctx) llvm.Type {
-	return e.Actual.LLVMInType(ctx)
-}
-
-// LLVMOutType passes through to the method on the underlying Actual
-func (e Expr) LLVMOutType(ctx *Ctx) llvm.Type {
-	return e.Actual.LLVMOutType(ctx)
-}
-
-// LLVMVal passes its arguments to the underlying Actual instance. It caches the
-// result, so if this is called multiple times the underlying one is only called
-// the first time.
-func (e Expr) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
-	if e.val == nil {
-		v := e.Actual.LLVMVal(ctx, lctx)
-		e.val = &v
-	}
-	return *e.val
-}
-
 // will panic if either Expr's Actual doesn't implement equaler
 func (e Expr) equal(e2 Expr) bool {
 	eq1, ok1 := e.Actual.(equaler)
@@ -88,21 +52,9 @@ func (e Expr) equal(e2 Expr) bool {
 // Void represents no data (size = 0)
 type Void struct{}
 
-// LLVMInType implements the Actual interface method
-func (v Void) LLVMInType(ctx *Ctx) llvm.Type {
-	panic("Void has no InType")
-}
-
-// LLVMOutType implements the Actual interface method
-func (v Void) LLVMOutType(ctx *Ctx) llvm.Type {
-	return llvm.VoidType()
-}
-
-// LLVMVal implements the Actual interface method
-func (v Void) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
-	// Kind of weird that this only works for return type, but I guess makes
-	// sense
-	return lctx.B.CreateRetVoid()
+func (v Void) equal(e equaler) bool {
+	_, ok := e.(Void)
+	return ok
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -110,21 +62,6 @@ func (v Void) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
 // Bool represents a true or false value
 type Bool bool
 
-// LLVMInType implements the Actual interface method
-func (b Bool) LLVMInType(ctx *Ctx) llvm.Type {
-	panic("Bool has no InType")
-}
-
-// LLVMOutType implements the Actual interface method
-func (b Bool) LLVMOutType(ctx *Ctx) llvm.Type {
-	return llvm.IntType(1)
-}
-
-// LLVMVal implements the Actual interface method
-func (b Bool) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
-	return llvm.Value{}
-}
-
 func (b Bool) equal(e equaler) bool {
 	bb, ok := e.(Bool)
 	if !ok {
@@ -138,18 +75,7 @@ func (b Bool) equal(e equaler) bool {
 // Int represents an integer value
 type Int int64
 
-// LLVMInType implements the Actual interface method
-func (i Int) LLVMInType(ctx *Ctx) llvm.Type {
-	panic("Int has no InType")
-}
-
-// LLVMOutType implements the Actual interface method
-func (i Int) LLVMOutType(ctx *Ctx) llvm.Type {
-	return llvm.Int64Type()
-}
-
-// LLVMVal implements the Actual interface method
-func (i Int) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
+func (i Int) build(lctx LLVMCtx) llvm.Value {
 	v := lctx.B.CreateAlloca(llvm.Int64Type(), "")
 	lctx.B.CreateStore(llvm.ConstInt(llvm.Int64Type(), uint64(i), false), v)
 	return v
@@ -157,10 +83,7 @@ func (i Int) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
 
 func (i Int) equal(e equaler) bool {
 	ii, ok := e.(Int)
-	if !ok {
-		return false
-	}
-	return ii == i
+	return ok && ii == i
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -168,21 +91,6 @@ func (i Int) equal(e equaler) bool {
 // String represents a string value
 type String string
 
-// LLVMInType implements the Actual interface method
-func (s String) LLVMInType(ctx *Ctx) llvm.Type {
-	panic("String has no InType")
-}
-
-// LLVMOutType implements the Actual interface method
-func (s String) LLVMOutType(ctx *Ctx) llvm.Type {
-	panic("TODO")
-}
-
-// LLVMVal implements the Actual interface method
-func (s String) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
-	panic("TODO")
-}
-
 func (s String) equal(e equaler) bool {
 	ss, ok := e.(String)
 	if !ok {
@@ -197,27 +105,9 @@ func (s String) equal(e equaler) bool {
 // name
 type Identifier string
 
-// LLVMInType implements the Actual interface method
-func (id Identifier) LLVMInType(ctx *Ctx) llvm.Type {
-	panic("TODO")
-}
-
-// LLVMOutType implements the Actual interface method
-func (id Identifier) LLVMOutType(ctx *Ctx) llvm.Type {
-	panic("TODO")
-}
-
-// LLVMVal implements the Actual interface method
-func (id Identifier) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
-	panic("TODO")
-}
-
 func (id Identifier) equal(e equaler) bool {
 	idid, ok := e.(Identifier)
-	if !ok {
-		return false
-	}
-	return idid == id
+	return ok && idid == id
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -232,27 +122,9 @@ func (m Macro) String() string {
 	return "%" + string(m)
 }
 
-// LLVMInType implements the Actual interface method
-func (m Macro) LLVMInType(ctx *Ctx) llvm.Type {
-	panic("Macro has no InType")
-}
-
-// LLVMOutType implements the Actual interface method
-func (m Macro) LLVMOutType(ctx *Ctx) llvm.Type {
-	panic("Macro has no OutType")
-}
-
-// LLVMVal implements the Actual interface method
-func (m Macro) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
-	panic("Macro has no Val")
-}
-
 func (m Macro) equal(e equaler) bool {
 	mm, ok := e.(Macro)
-	if !ok {
-		return false
-	}
-	return m == mm
+	return ok && m == mm
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -262,39 +134,12 @@ func (m Macro) equal(e equaler) bool {
 type Tuple []Expr
 
 func (tup Tuple) String() string {
-	strs := make([]string, len(tup))
-	for i := range tup {
-		strs[i] = fmt.Sprint(tup[i].Actual)
-	}
-	return "(" + strings.Join(strs, ", ") + ")"
-}
-
-// LLVMInType implements the Actual interface method
-func (tup Tuple) LLVMInType(ctx *Ctx) llvm.Type {
-	panic("TODO")
-}
-
-// LLVMOutType implements the Actual interface method
-func (tup Tuple) LLVMOutType(ctx *Ctx) llvm.Type {
-	panic("TODO")
-}
-
-// LLVMVal implements the Actual interface method
-func (tup Tuple) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
-	panic("TODO")
+	return "(" + exprsJoin(tup) + ")"
 }
 
 func (tup Tuple) equal(e equaler) bool {
 	tuptup, ok := e.(Tuple)
-	if !ok || len(tuptup) != len(tup) {
-		return false
-	}
-	for i := range tup {
-		if !tup[i].equal(tuptup[i]) {
-			return false
-		}
-	}
-	return true
+	return ok && exprsEqual(tup, tuptup)
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -303,89 +148,39 @@ func (tup Tuple) equal(e equaler) bool {
 // used as the input to the pipe, and the output of the pipe is the output of
 // the statement
 type Statement struct {
-	// TODO change to Op and Arg
-	In Expr
-	To Expr
+	Op, Arg Expr
 }
 
 func (s Statement) String() string {
-	return fmt.Sprintf("(%v > %s)", s.In.Actual, s.To.Actual)
-}
-
-func (s Statement) maybeMacro(ctx *Ctx) (Expr, bool) {
-	m, ok := s.To.Actual.(Macro)
-	if !ok {
-		return Expr{}, false
-	}
-
-	fn := ctx.GetMacro(m)
-	if fn == nil {
-		return Expr{}, false
-	}
-	newe, err := fn(s.In)
-	if err != nil {
-		// TODO proper error
-		panic(err)
-	}
-	return newe, true
-}
-
-// LLVMInType implements the Actual interface method
-func (s Statement) LLVMInType(ctx *Ctx) llvm.Type {
-	if newe, ok := s.maybeMacro(ctx); ok {
-		return newe.LLVMInType(ctx)
-	}
-	// TODO futures
-	panic("unknown Statement.To")
-}
-
-// LLVMOutType implements the Actual interface method
-func (s Statement) LLVMOutType(ctx *Ctx) llvm.Type {
-	if newe, ok := s.maybeMacro(ctx); ok {
-		return newe.LLVMOutType(ctx)
-	}
-	panic("unknown Statement.To")
-}
-
-// LLVMVal implements the Actual interface method
-func (s Statement) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
-	if newe, ok := s.maybeMacro(ctx); ok {
-		return newe.LLVMVal(ctx, lctx)
-	}
-	panic("unknown Statement.To")
+	return fmt.Sprintf("(%v %s)", s.Op.Actual, s.Arg.Actual)
 }
 
 func (s Statement) equal(e equaler) bool {
 	ss, ok := e.(Statement)
-	return ok && s.In.equal(ss.In) && s.To.equal(ss.To)
+	return ok && s.Op.equal(ss.Op) && s.Arg.equal(ss.Arg)
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
 // Block represents a set of statements which share a scope, i.e. If one
 // statement binds a variable the rest of the statements in the block can use
-// that variable, including sub-blocks within this one.
-type Block []Expr
+// that variable
+type Block struct {
+	In    []Expr
+	Stmts []Expr
+	Out   []Expr
+}
 
 func (b Block) String() string {
-	strs := make([]string, len(b))
-	for i := range b {
-		strs[i] = b[i].Actual.(Statement).String()
-	}
-	return fmt.Sprintf("{ %s }", strings.Join(strs, " "))
+	return fmt.Sprintf(
+		"{[%s][%s][%s]}",
+		exprsJoin(b.In),
+		exprsJoin(b.Stmts),
+		exprsJoin(b.Out),
+	)
 }
 
-// LLVMInType implements the Actual interface method
-func (b Block) LLVMInType(ctx *Ctx) llvm.Type {
-	panic("TODO")
-}
-
-// LLVMOutType implements the Actual interface method
-func (b Block) LLVMOutType(ctx *Ctx) llvm.Type {
-	return b[len(b)-1].LLVMOutType(ctx)
-}
-
-// LLVMVal implements the Actual interface method
+/*
 func (b Block) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
 	name := randStr() // TODO make this based on token
 	// TODO make these based on actual statements
@@ -404,16 +199,12 @@ func (b Block) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
 	lctx.B.CreateRet(v)
 	return fn
 }
+*/
 
 func (b Block) equal(e equaler) bool {
 	bb, ok := e.(Block)
-	if !ok {
-		return false
-	}
-	for i := range b {
-		if !b[i].equal(bb[i]) {
-			return false
-		}
-	}
-	return true
+	return ok &&
+		exprsEqual(b.In, bb.In) &&
+		exprsEqual(b.Stmts, bb.Stmts) &&
+		exprsEqual(b.Out, bb.Out)
 }
diff --git a/expr/macros.go b/expr/macros.go
index 0e21dd1..3abeb14 100644
--- a/expr/macros.go
+++ b/expr/macros.go
@@ -1,45 +1,23 @@
 package expr
 
-import (
-	"errors"
-
-	"llvm.org/llvm/bindings/go/llvm"
-)
-
-type addActual []Expr
-
-func (aa addActual) LLVMInType(ctx *Ctx) llvm.Type {
-	panic("addActual has no InType")
-}
-
-func (aa addActual) LLVMOutType(ctx *Ctx) llvm.Type {
-	return aa[0].LLVMOutType(ctx)
-}
-
-func (aa addActual) LLVMVal(ctx *Ctx, lctx LLVMCtx) llvm.Value {
-	a := lctx.B.CreateLoad(aa[0].LLVMVal(ctx, lctx), "")
-	for i := range aa[1:] {
-		b := lctx.B.CreateLoad(aa[i+1].LLVMVal(ctx, lctx), "")
-		a = lctx.B.CreateAdd(a, b, "")
-	}
-	return a
-}
+import "llvm.org/llvm/bindings/go/llvm"
 
 // RootCtx describes what's available to *all* contexts, and is what all
 // contexts should have as the root parent in the tree
 var RootCtx = &Ctx{
-	Macros: map[Macro]func(Expr) (Expr, error){
-		"add": func(e Expr) (Expr, error) {
-			tup, ok := e.Actual.(Tuple)
-			if !ok {
-				// TODO proper error
-				return Expr{}, errors.New("add only accepts a tuple")
+	Macros: map[Macro]MacroFn{
+		"add": func(ctx *Ctx, lctx LLVMCtx, e Expr) (llvm.Value, bool) {
+			tup := e.Actual.(Tuple)
+			buildInt := func(e Expr) llvm.Value {
+				return lctx.B.CreateLoad(e.Actual.(Int).build(lctx), "")
 			}
-			// TODO check that it's a tuple of integers too
-			return Expr{
-				Actual: addActual(tup),
-				Token:  e.Token,
-			}, nil
+
+			a := buildInt(tup[0])
+			for i := range tup[1:] {
+				b := buildInt(tup[i+1])
+				a = lctx.B.CreateAdd(a, b, "")
+			}
+			return a, true
 		},
 	},
 }
diff --git a/expr/util.go b/expr/util.go
index 7648094..1cdc336 100644
--- a/expr/util.go
+++ b/expr/util.go
@@ -2,7 +2,9 @@ package expr
 
 import (
 	"encoding/hex"
+	"fmt"
 	"math/rand"
+	"strings"
 )
 
 func randStr() string {
@@ -12,3 +14,27 @@ func randStr() string {
 	}
 	return hex.EncodeToString(b)
 }
+
+func exprsJoin(ee []Expr) string {
+	strs := make([]string, len(ee))
+	for i := range ee {
+		strs[i] = fmt.Sprint(ee[i].Actual)
+	}
+	return strings.Join(strs, ", ")
+}
+
+func exprsEqual(ee1, ee2 []Expr) bool {
+	if len(ee1) != len(ee2) {
+		return false
+	}
+	for i := range ee1 {
+		if !ee1[i].equal(ee2[i]) {
+			return false
+		}
+	}
+	return true
+}
+
+func panicf(msg string, args ...interface{}) {
+	panic(fmt.Sprintf(msg, args...))
+}
diff --git a/main.go b/main.go
index ef3c819..2a6a852 100644
--- a/main.go
+++ b/main.go
@@ -33,17 +33,20 @@ func main() {
 	c := expr.Expr{Actual: expr.Int(3)}
 	tup := expr.Expr{Actual: expr.Tuple([]expr.Expr{a, b, c})}
 	addMacro := expr.Expr{Actual: expr.Macro("add")}
-	stmt := expr.Expr{Actual: expr.Statement{In: tup, To: addMacro}}
-	block := expr.Block([]expr.Expr{stmt})
-	fn := block.LLVMVal(expr.RootCtx, lctx)
+	stmt := expr.Expr{Actual: expr.Statement{Op: addMacro, Arg: tup}}
+
+	//block := expr.Block([]expr.Expr{stmt})
+	//fn := block.LLVMVal(expr.RootCtx, lctx)
 
 	// create main and call our function
 	mainFn := llvm.AddFunction(lctx.M, "main", llvm.FunctionType(llvm.Int64Type(), []llvm.Type{}, false))
 	mainBlock := llvm.AddBasicBlock(mainFn, "entry")
 	lctx.B.SetInsertPoint(mainBlock, mainBlock.FirstInstruction())
+	expr.BuildStmt(expr.RootCtx, lctx, stmt)
+	lctx.B.CreateRet(expr.RootCtx.LastVal)
 
-	ret := lctx.B.CreateCall(fn, []llvm.Value{}, "")
-	lctx.B.CreateRet(ret)
+	//ret := lctx.B.CreateCall(fn, []llvm.Value{}, "")
+	//lctx.B.CreateRet(ret)
 
 	// verify it's all good
 	if err := llvm.VerifyModule(lctx.M, llvm.ReturnStatusAction); err != nil {