diff --git a/ble_darwin.go b/ble_darwin.go
index 3d1e59c..fa499a2 100644
--- a/ble_darwin.go
+++ b/ble_darwin.go
@@ -10,6 +10,7 @@ import (
 	"time"
 	"unsafe"
 
+	"git.wow.st/gmp/ble/gatt"
 	"git.wow.st/gmp/ble/ns"
 )
 
@@ -29,6 +30,8 @@ type BLE struct {
 
 var cdLookup map[unsafe.Pointer]*BLE
 var pdLookup map[unsafe.Pointer]*BLE
+var pcache map[unsafe.Pointer]*Peripheral
+
 
 type State string
 
@@ -50,11 +53,20 @@ func peripheralName(p *ns.CBPeripheral) string {
 }
 
 func newPeripheral(x *ns.CBPeripheral) Peripheral {
-	return Peripheral{
+	if pcache == nil {
+		pcache = make(map[unsafe.Pointer]*Peripheral)
+	} else {
+		if ret,ok := pcache[x.Ptr()]; ok {
+			return *ret
+		}
+	}
+	ret := Peripheral{
 		Name:       peripheralName(x),
 		Identifier: x.Identifier().UUIDString().String(),
 		p:          x,
 	}
+	pcache[x.Ptr()] = &ret
+	return ret
 }
 
 type PeripheralListItem struct {
@@ -135,10 +147,23 @@ type UpdateStateEvent struct {
 	State string
 }
 
-type DiscoverEvent struct {
+type DiscoverPeripheralEvent struct {
 	Peripheral Peripheral
 }
 
+type DiscoverServiceEvent struct {
+	Peripheral Peripheral
+	Gatt gatt.Service
+	Service *ns.CBService
+}
+
+type DiscoverCharacteristicEvent struct {
+	Peripheral Peripheral
+	Gatt gatt.Characteristic
+	Service *ns.CBService
+	Characteristic *ns.CBCharacteristic
+}
+
 type ConnectEvent struct {
 	Peripheral Peripheral
 }
@@ -146,6 +171,11 @@ type ConnectTimeoutEvent struct {
 	Peripheral Peripheral
 }
 
+type UpdageValueEvent struct {
+	Peripheral Peripheral
+	Characteristic gatt.Characteristic
+}
+
 func (b *BLE) Events() chan interface{} {
 	return b.events
 }
@@ -298,7 +328,7 @@ func discoverPeripheral(c *ns.CBCentralManager, p *ns.CBPeripheral, d *ns.NSDict
 	}
 	if ok := b.peripherals.Add(peripheral); ok {
 		pdLookup[p.Ptr()] = b
-		b.events <- DiscoverEvent{Peripheral: peripheral}
+		b.events <- DiscoverPeripheralEvent{Peripheral: peripheral}
 	}
 }
 
@@ -335,7 +365,7 @@ func connectPeripheral(c *ns.CBCentralManager, p *ns.CBPeripheral) {
 	fmt.Printf("Go: connectPeripheral returning\n")
 }
 
-func DiscoverServices(x Peripheral) {
+func (x Peripheral) DiscoverServices() {
 	fmt.Printf("Discovering services on %s\n", x.Name)
 	p := x.p
 
@@ -345,19 +375,15 @@ func DiscoverServices(x Peripheral) {
 }
 
 func discoverServices(p *ns.CBPeripheral, e *ns.NSError) {
+	b := pdLookup[p.Ptr()]
 	fmt.Printf("Did discover services\n")
 	p.Services().ObjectEnumerator().ForIn(func(o *ns.Id) bool {
 		serv := o.CBService()
-		uuid := serv.UUID()
-		switch {
-		case uuid.IsEqualTo(hrm_uuid):
-			fmt.Printf("--heart rate monitor service\n")
-			p.DiscoverCharacteristics(nil, serv)
-		case uuid.IsEqualTo(info_uuid):
-			fmt.Printf("--device information service\n")
-			p.DiscoverCharacteristics(nil, serv)
-		default:
-			fmt.Printf("--unknown service\n")
+		uuid := serv.UUID().UUIDString().String()
+		b.events <-DiscoverServiceEvent{
+			Peripheral: newPeripheral(p),
+			Gatt: gatt.Service{uuid},
+			Service: serv,
 		}
 		return true
 	})
@@ -377,26 +403,32 @@ func hr(d *ns.NSData) int {
 	}
 }
 
+func (p Peripheral) DiscoverCharacteristics(serv *ns.CBService) {
+	p.p.DiscoverCharacteristics(nil, serv)
+}
+
 func discoverCharacteristics(p *ns.CBPeripheral, s *ns.CBService, e *ns.NSError) {
+	b := pdLookup[p.Ptr()]
 	fmt.Printf("Did discover characteristics\n")
-	uuid := s.UUID()
-	fmt.Printf("----%s\n", uuid.UUIDString())
-	if uuid.IsEqualTo(hrm_uuid) {
-		s.Characteristics().ObjectEnumerator().ForIn(func(o *ns.Id) bool {
-			chr := o.CBCharacteristic()
-			chuuid := chr.UUID()
-			fmt.Printf("------%s\n", chuuid.UUIDString())
-			if chuuid.IsEqualTo(hrv_uuid) {
-				p.SetNotifyValue(1, chr)
-				v := chr.Value()
-				fmt.Println(hr(v))
-			}
-			return true
-		})
-	}
+	s.Characteristics().ObjectEnumerator().ForIn(func(o *ns.Id) bool {
+		chr := o.CBCharacteristic()
+		chuuid := chr.UUID()
+		fmt.Printf("------%s\n", chuuid.UUIDString())
+		b.events <-DiscoverCharacteristicEvent{
+			Peripheral: newPeripheral(p),
+			Service: s,
+			Characteristic: chr,
+			Gatt: gatt.Characteristic{chuuid.UUIDString().String()},
+		}
+		return true
+	})
 	fmt.Printf("Go: discoverCharacteristics returning\n")
 }
 
+func (p Peripheral) SetNotifyValue(c *ns.CBCharacteristic) {
+	p.p.SetNotifyValue(1, c)
+}
+
 func updateValue(p *ns.CBPeripheral, chr *ns.CBCharacteristic, e *ns.NSError) {
 	//ble := pdLookup[p]
 	ble := gble
diff --git a/gatt/main.go b/gatt/main.go
new file mode 100644
index 0000000..a69e110
--- /dev/null
+++ b/gatt/main.go
@@ -0,0 +1,17 @@
+package gatt
+
+import (
+)
+
+type Service struct {
+	UUID string
+}
+
+type Descriptor struct {
+	UUID string
+}
+
+type Characteristic struct {
+	UUID string
+}
+