diff --git a/emulator/director.go b/emulator/director.go
index 6eba51a5..9c911e54 100644
--- a/emulator/director.go
+++ b/emulator/director.go
@@ -9,21 +9,23 @@ import (
 	// "github.com/gordonklaus/portaudio"
 )
 
+// Director is the nes emulator
 type Director struct {
 	// audio        *Audio
 	view         *GameView
 	timestamp    float64
-	imageChannel chan *image.RGBA
-	audioChannel chan float32
-	inputChannel chan int
+	imageChannel chan<- *image.RGBA
+	audioChannel chan<- float32
+	inputChannel <-chan int
 	Done         chan struct{}
 
 	roomID string
 }
 
-const FPS = 60
+const fps = 60
 
-func NewDirector(roomID string, imageChannel chan *image.RGBA, audioChannel chan float32, inputChannel chan int) *Director {
+// NewDirector returns a new director
+func NewDirector(roomID string, imageChannel chan<- *image.RGBA, audioChannel chan<- float32, inputChannel <-chan int) *Director {
 	// TODO: return image channel from where it write
 	director := Director{}
 	director.Done = make(chan struct{})
@@ -34,6 +36,7 @@ func NewDirector(roomID string, imageChannel chan *image.RGBA, audioChannel chan
 	return &director
 }
 
+// SetView ...
 func (d *Director) SetView(view *GameView) {
 	if d.view != nil {
 		d.view.Exit()
@@ -49,6 +52,7 @@ func (d *Director) SetView(view *GameView) {
 //d.view.UpdateInput(input)
 //}
 
+// Step ...
 func (d *Director) Step() {
 	timestamp := float64(time.Now().Nanosecond()) / float64(time.Second)
 	dt := timestamp - d.timestamp
@@ -58,6 +62,7 @@ func (d *Director) Step() {
 	}
 }
 
+// Start ...
 func (d *Director) Start(paths []string) {
 	// portaudio.Initialize()
 	// defer portaudio.Terminate()
@@ -73,8 +78,9 @@ func (d *Director) Start(paths []string) {
 	d.Run()
 }
 
+// Run ...
 func (d *Director) Run() {
-	c := time.Tick(time.Second / FPS)
+	c := time.Tick(time.Second / fps)
 L:
 	for range c {
 		// for {
@@ -96,6 +102,7 @@ L:
 	log.Println("Closed Director")
 }
 
+// PalyGame starts a game given a rom path
 func (d *Director) PlayGame(path string) {
 	console, err := nes.NewConsole(path)
 	if err != nil {
diff --git a/emulator/gameview.go b/emulator/gameview.go
index 5a4c270f..0be6c22b 100644
--- a/emulator/gameview.go
+++ b/emulator/gameview.go
@@ -49,9 +49,9 @@ type GameView struct {
 	savingJob  *job
 	loadingJob *job
 
-	imageChannel chan *image.RGBA
-	audioChannel chan float32
-	inputChannel chan int
+	imageChannel chan<- *image.RGBA
+	audioChannel chan<- float32
+	inputChannel <-chan int
 }
 
 type job struct {
@@ -59,7 +59,7 @@ type job struct {
 	extraFunc func() error
 }
 
-func NewGameView(console *nes.Console, title, saveFile string, imageChannel chan *image.RGBA, audioChannel chan float32, inputChannel chan int) *GameView {
+func NewGameView(console *nes.Console, title, saveFile string, imageChannel chan<- *image.RGBA, audioChannel chan<- float32, inputChannel <-chan int) *GameView {
 	gameview := &GameView{
 		console:      console,
 		title:        title,
diff --git a/emulator/nes/apu.go b/emulator/nes/apu.go
index 33b10578..8a1a2aff 100644
--- a/emulator/nes/apu.go
+++ b/emulator/nes/apu.go
@@ -45,7 +45,7 @@ func init() {
 
 type APU struct {
 	console     *Console
-	channel     chan float32
+	channel     chan<- float32
 	sampleRate  float64
 	pulse1      Pulse
 	pulse2      Pulse
diff --git a/emulator/nes/console.go b/emulator/nes/console.go
index 2dbd0d11..d884a865 100644
--- a/emulator/nes/console.go
+++ b/emulator/nes/console.go
@@ -89,7 +89,7 @@ func (console *Console) SetButtons2(buttons [8]bool) {
 	console.Controller2.SetButtons(buttons)
 }
 
-func (console *Console) SetAudioChannel(channel chan float32) {
+func (console *Console) SetAudioChannel(channel chan<- float32) {
 	console.APU.channel = channel
 }
 
diff --git a/worker/room/room.go b/worker/room/room.go
index 7047078a..8e855a17 100644
--- a/worker/room/room.go
+++ b/worker/room/room.go
@@ -19,12 +19,12 @@ import (
 type Room struct {
 	ID string
 
-	// imageChannel is image stream from director
-	imageChannel chan *image.RGBA
-	// audioChannel is audio stream from director
-	audioChannel chan float32
-	// inputChannel is input stream from websocket to room
-	inputChannel chan int
+	// imageChannel is image stream received from director
+	imageChannel <-chan *image.RGBA
+	// audioChannel is audio stream received from director
+	audioChannel <-chan float32
+	// inputChannel is input stream from websocket send to room
+	inputChannel chan<- int
 	// State of room
 	IsRunning bool
 	// Done channel is to fire exit event when room is closed