diff --git a/connection.go b/connection.go
index c4a36c5cb..65f6a407e 100644
--- a/connection.go
+++ b/connection.go
@@ -144,7 +144,7 @@ type connection struct {
 	sentPacketHandler     ackhandler.SentPacketHandler
 	receivedPacketHandler ackhandler.ReceivedPacketHandler
 	retransmissionQueue   *retransmissionQueue
-	framer                framer
+	framer                *framer
 	windowUpdateQueue     *windowUpdateQueue
 	connFlowController    flowcontrol.ConnectionFlowController
 	tokenStoreKey         string                    // only set for the client
diff --git a/framer.go b/framer.go
index 5eef65372..452dc1322 100644
--- a/framer.go
+++ b/framer.go
@@ -11,31 +11,12 @@ import (
 	"github.com/quic-go/quic-go/quicvarint"
 )
 
-type framer interface {
-	HasData() bool
-
-	QueueControlFrame(wire.Frame)
-	AppendControlFrames([]ackhandler.Frame, protocol.ByteCount, protocol.Version) ([]ackhandler.Frame, protocol.ByteCount)
-
-	AddActiveStream(protocol.StreamID)
-	AppendStreamFrames([]ackhandler.StreamFrame, protocol.ByteCount, protocol.Version) ([]ackhandler.StreamFrame, protocol.ByteCount)
-
-	Handle0RTTRejection() error
-
-	// QueuedTooManyControlFrames says if the control frame queue exceeded its maximum queue length.
-	// This is a hack.
-	// It is easier to implement than propagating an error return value in QueueControlFrame.
-	// The correct solution would be to queue frames with their respective structs.
-	// See https://github.com/quic-go/quic-go/issues/4271 for the queueing of stream-related control frames.
-	QueuedTooManyControlFrames() bool
-}
-
 const (
 	maxPathResponses = 256
 	maxControlFrames = 16 << 10
 )
 
-type framerI struct {
+type framer struct {
 	mutex sync.Mutex
 
 	streamGetter streamGetter
@@ -49,16 +30,14 @@ type framerI struct {
 	queuedTooManyControlFrames bool
 }
 
-var _ framer = &framerI{}
-
-func newFramer(streamGetter streamGetter) framer {
-	return &framerI{
+func newFramer(streamGetter streamGetter) *framer {
+	return &framer{
 		streamGetter:  streamGetter,
 		activeStreams: make(map[protocol.StreamID]struct{}),
 	}
 }
 
-func (f *framerI) HasData() bool {
+func (f *framer) HasData() bool {
 	f.mutex.Lock()
 	hasData := !f.streamQueue.Empty()
 	f.mutex.Unlock()
@@ -70,7 +49,7 @@ func (f *framerI) HasData() bool {
 	return len(f.controlFrames) > 0 || len(f.pathResponses) > 0
 }
 
-func (f *framerI) QueueControlFrame(frame wire.Frame) {
+func (f *framer) QueueControlFrame(frame wire.Frame) {
 	f.controlFrameMutex.Lock()
 	defer f.controlFrameMutex.Unlock()
 
@@ -92,7 +71,7 @@ func (f *framerI) QueueControlFrame(frame wire.Frame) {
 	f.controlFrames = append(f.controlFrames, frame)
 }
 
-func (f *framerI) AppendControlFrames(frames []ackhandler.Frame, maxLen protocol.ByteCount, v protocol.Version) ([]ackhandler.Frame, protocol.ByteCount) {
+func (f *framer) AppendControlFrames(frames []ackhandler.Frame, maxLen protocol.ByteCount, v protocol.Version) ([]ackhandler.Frame, protocol.ByteCount) {
 	f.controlFrameMutex.Lock()
 	defer f.controlFrameMutex.Unlock()
 
@@ -121,11 +100,16 @@ func (f *framerI) AppendControlFrames(frames []ackhandler.Frame, maxLen protocol
 	return frames, length
 }
 
-func (f *framerI) QueuedTooManyControlFrames() bool {
+// QueuedTooManyControlFrames says if the control frame queue exceeded its maximum queue length.
+// This is a hack.
+// It is easier to implement than propagating an error return value in QueueControlFrame.
+// The correct solution would be to queue frames with their respective structs.
+// See https://github.com/quic-go/quic-go/issues/4271 for the queueing of stream-related control frames.
+func (f *framer) QueuedTooManyControlFrames() bool {
 	return f.queuedTooManyControlFrames
 }
 
-func (f *framerI) AddActiveStream(id protocol.StreamID) {
+func (f *framer) AddActiveStream(id protocol.StreamID) {
 	f.mutex.Lock()
 	if _, ok := f.activeStreams[id]; !ok {
 		f.streamQueue.PushBack(id)
@@ -134,7 +118,7 @@ func (f *framerI) AddActiveStream(id protocol.StreamID) {
 	f.mutex.Unlock()
 }
 
-func (f *framerI) AppendStreamFrames(frames []ackhandler.StreamFrame, maxLen protocol.ByteCount, v protocol.Version) ([]ackhandler.StreamFrame, protocol.ByteCount) {
+func (f *framer) AppendStreamFrames(frames []ackhandler.StreamFrame, maxLen protocol.ByteCount, v protocol.Version) ([]ackhandler.StreamFrame, protocol.ByteCount) {
 	startLen := len(frames)
 	var length protocol.ByteCount
 	f.mutex.Lock()
@@ -183,7 +167,7 @@ func (f *framerI) AppendStreamFrames(frames []ackhandler.StreamFrame, maxLen pro
 	return frames, length
 }
 
-func (f *framerI) Handle0RTTRejection() error {
+func (f *framer) Handle0RTTRejection() error {
 	f.mutex.Lock()
 	defer f.mutex.Unlock()
 
diff --git a/framer_test.go b/framer_test.go
index 6d364423c..89f11df87 100644
--- a/framer_test.go
+++ b/framer_test.go
@@ -21,7 +21,7 @@ var _ = Describe("Framer", func() {
 	)
 
 	var (
-		framer           framer
+		framer           *framer
 		stream1, stream2 *MockSendStreamI
 		streamGetter     *MockStreamGetter
 		version          protocol.Version
@@ -117,14 +117,14 @@ var _ = Describe("Framer", func() {
 				Expect(framer.QueuedTooManyControlFrames()).To(BeFalse())
 				frames, _ := framer.AppendControlFrames([]ackhandler.Frame{}, 1, protocol.Version1)
 				Expect(frames).To(HaveLen(1))
-				Expect(framer.(*framerI).controlFrames).To(HaveLen(i + 1))
+				Expect(framer.controlFrames).To(HaveLen(i + 1))
 			}
 			framer.QueueControlFrame(&wire.PingFrame{})
 			Expect(framer.QueuedTooManyControlFrames()).To(BeFalse())
-			Expect(framer.(*framerI).controlFrames).To(HaveLen(maxControlFrames))
+			Expect(framer.controlFrames).To(HaveLen(maxControlFrames))
 			framer.QueueControlFrame(&wire.PingFrame{})
 			Expect(framer.QueuedTooManyControlFrames()).To(BeTrue())
-			Expect(framer.(*framerI).controlFrames).To(HaveLen(maxControlFrames))
+			Expect(framer.controlFrames).To(HaveLen(maxControlFrames))
 		})
 	})