diff --git a/pkg/types/orderbook.go b/pkg/types/orderbook.go
index 6f47bf19e..79c8a022d 100644
--- a/pkg/types/orderbook.go
+++ b/pkg/types/orderbook.go
@@ -40,6 +40,13 @@ func (slice PriceVolumeSlice) Copy() PriceVolumeSlice {
 	return append(slice[:0:0], slice...)
 }
 
+func (slice PriceVolumeSlice) First() (PriceVolume, bool) {
+	if len(slice) > 0 {
+		return slice[0], true
+	}
+	return PriceVolume{}, false
+}
+
 func (slice PriceVolumeSlice) IndexByVolumeDepth(requiredVolume fixedpoint.Value) int {
 	var tv int64 = 0
 	for x, el := range slice {
diff --git a/pkg/types/standardstream_callbacks.go b/pkg/types/standardstream_callbacks.go
index 967ae52e3..360e34651 100644
--- a/pkg/types/standardstream_callbacks.go
+++ b/pkg/types/standardstream_callbacks.go
@@ -2,18 +2,26 @@
 
 package types
 
-import ()
-
-func (stream *StandardStream) OnTrade(cb func(trade Trade)) {
-	stream.tradeCallbacks = append(stream.tradeCallbacks, cb)
+func (stream *StandardStream) OnTradeUpdate(cb func(trade Trade)) {
+	stream.tradeUpdateCallbacks = append(stream.tradeUpdateCallbacks, cb)
 }
 
-func (stream *StandardStream) EmitTrade(trade Trade) {
-	for _, cb := range stream.tradeCallbacks {
+func (stream *StandardStream) EmitTradeUpdate(trade Trade) {
+	for _, cb := range stream.tradeUpdateCallbacks {
 		cb(trade)
 	}
 }
 
+func (stream *StandardStream) OnOrderUpdate(cb func(order Order)) {
+	stream.orderUpdateCallbacks = append(stream.orderUpdateCallbacks, cb)
+}
+
+func (stream *StandardStream) EmitOrderUpdate(order Order) {
+	for _, cb := range stream.orderUpdateCallbacks {
+		cb(order)
+	}
+}
+
 func (stream *StandardStream) OnBalanceSnapshot(cb func(balances map[string]Balance)) {
 	stream.balanceSnapshotCallbacks = append(stream.balanceSnapshotCallbacks, cb)
 }
@@ -75,7 +83,9 @@ func (stream *StandardStream) EmitBookSnapshot(book OrderBook) {
 }
 
 type StandardStreamEventHub interface {
-	OnTrade(cb func(trade Trade))
+	OnTradeUpdate(cb func(trade Trade))
+
+	OnOrderUpdate(cb func(order Order))
 
 	OnBalanceSnapshot(cb func(balances map[string]Balance))
 
diff --git a/pkg/types/stream.go b/pkg/types/stream.go
index b55ffd009..3f3e59f96 100644
--- a/pkg/types/stream.go
+++ b/pkg/types/stream.go
@@ -22,8 +22,11 @@ var KLineChannel = Channel("kline")
 type StandardStream struct {
 	Subscriptions []Subscription
 
-	// private trade callbacks
-	tradeCallbacks []func(trade Trade)
+	// private trade update callbacks
+	tradeUpdateCallbacks []func(trade Trade)
+
+	// private order update callbacks
+	orderUpdateCallbacks []func(order Order)
 
 	// balance snapshot callbacks
 	balanceSnapshotCallbacks []func(balances map[string]Balance)