diff --git a/crypto_stream.go b/crypto_stream.go
index 7589cdc0d..fbf7324ce 100644
--- a/crypto_stream.go
+++ b/crypto_stream.go
@@ -5,6 +5,8 @@ import (
 	"encoding/binary"
 	"errors"
 	"sort"
+
+	"github.com/lucas-clemente/quic-go/utils"
 )
 
 // A Tag in the QUIC crypto
@@ -116,9 +118,9 @@ func ParseCryptoMessage(data []byte) (Tag, map[Tag][]byte, error) {
 
 // WriteCryptoMessage writes a crypto message
 func WriteCryptoMessage(b *bytes.Buffer, messageTag Tag, data map[Tag][]byte) {
-	writeUint32(b, uint32(messageTag))
-	writeUint16(b, uint16(len(data)))
-	writeUint16(b, 0)
+	utils.WriteUint32(b, uint32(messageTag))
+	utils.WriteUint16(b, uint16(len(data)))
+	utils.WriteUint16(b, 0)
 
 	// Save current position in the buffer, so that we can update the index in-place later
 	indexStart := b.Len()
@@ -133,7 +135,7 @@ func WriteCryptoMessage(b *bytes.Buffer, messageTag Tag, data map[Tag][]byte) {
 		tags[i] = uint32(t)
 		i++
 	}
-	sort.Sort(Uint32Slice(tags))
+	sort.Sort(utils.Uint32Slice(tags))
 
 	offset := uint32(0)
 	for i, t := range tags {
diff --git a/frame.go b/frame.go
index dd9f2abab..8ccf142c5 100644
--- a/frame.go
+++ b/frame.go
@@ -3,6 +3,8 @@ package quic
 import (
 	"bytes"
 	"io/ioutil"
+
+	"github.com/lucas-clemente/quic-go/utils"
 )
 
 // A StreamFrame of QUIC
@@ -29,20 +31,20 @@ func ParseStreamFrame(r *bytes.Reader) (*StreamFrame, error) {
 	}
 	streamIDLen := typeByte&0x03 + 1
 
-	sid, err := readUintN(r, streamIDLen)
+	sid, err := utils.ReadUintN(r, streamIDLen)
 	if err != nil {
 		return nil, err
 	}
 	frame.StreamID = uint32(sid)
 
-	frame.Offset, err = readUintN(r, offsetLen)
+	frame.Offset, err = utils.ReadUintN(r, offsetLen)
 	if err != nil {
 		return nil, err
 	}
 
 	var dataLen uint16
 	if dataLenPresent {
-		dataLen, err = readUint16(r)
+		dataLen, err = utils.ReadUint16(r)
 		if err != nil {
 			return nil, err
 		}
@@ -76,10 +78,10 @@ func WriteStreamFrame(b *bytes.Buffer, f *StreamFrame) {
 	}
 	typeByte ^= 0x03 // TODO: Send shorter stream ID if possible
 	b.WriteByte(typeByte)
-	writeUint32(b, f.StreamID)
+	utils.WriteUint32(b, f.StreamID)
 	if f.Offset != 0 {
-		writeUint64(b, f.Offset)
+		utils.WriteUint64(b, f.Offset)
 	}
-	writeUint16(b, uint16(len(f.Data)))
+	utils.WriteUint16(b, uint16(len(f.Data)))
 	b.Write(f.Data)
 }
diff --git a/public_header.go b/public_header.go
index cf2b08257..0c6c46157 100644
--- a/public_header.go
+++ b/public_header.go
@@ -3,6 +3,8 @@ package quic
 import (
 	"bytes"
 	"io"
+
+	"github.com/lucas-clemente/quic-go/utils"
 )
 
 // The PublicHeader of a QUIC packet
@@ -47,7 +49,7 @@ func ParsePublicHeader(b io.ByteReader) (*PublicHeader, error) {
 	}
 
 	// Connection ID
-	header.ConnectionID, err = readUintN(b, connectionIDLen)
+	header.ConnectionID, err = utils.ReadUintN(b, connectionIDLen)
 	if err != nil {
 		return nil, err
 	}
@@ -55,7 +57,7 @@ func ParsePublicHeader(b io.ByteReader) (*PublicHeader, error) {
 	// Version (optional)
 	if header.VersionFlag {
 		var v uint64
-		v, err = readUintN(b, 4)
+		v, err = utils.ReadUintN(b, 4)
 		if err != nil {
 			return nil, err
 		}
@@ -63,7 +65,7 @@ func ParsePublicHeader(b io.ByteReader) (*PublicHeader, error) {
 	}
 
 	// Packet number
-	header.PacketNumber, err = readUintN(b, packetNumberLen)
+	header.PacketNumber, err = utils.ReadUintN(b, packetNumberLen)
 	if err != nil {
 		return nil, err
 	}
diff --git a/utils.go b/utils/utils.go
similarity index 76%
rename from utils.go
rename to utils/utils.go
index e799b1b9d..acf8d28e6 100644
--- a/utils.go
+++ b/utils/utils.go
@@ -1,11 +1,12 @@
-package quic
+package utils
 
 import (
 	"bytes"
 	"io"
 )
 
-func readUintN(b io.ByteReader, length uint8) (uint64, error) {
+// ReadUintN reads N bytes
+func ReadUintN(b io.ByteReader, length uint8) (uint64, error) {
 	var res uint64
 	for i := uint8(0); i < length; i++ {
 		bt, err := b.ReadByte()
@@ -17,7 +18,8 @@ func readUintN(b io.ByteReader, length uint8) (uint64, error) {
 	return res, nil
 }
 
-func readUint32(b io.ByteReader) (uint32, error) {
+// ReadUint32 reads a uint32
+func ReadUint32(b io.ByteReader) (uint32, error) {
 	var b1, b2, b3, b4 uint8
 	var err error
 	if b1, err = b.ReadByte(); err != nil {
@@ -35,7 +37,8 @@ func readUint32(b io.ByteReader) (uint32, error) {
 	return uint32(b1) + uint32(b2)<<8 + uint32(b3)<<16 + uint32(b4)<<24, nil
 }
 
-func readUint16(b io.ByteReader) (uint16, error) {
+// ReadUint16 reads a uint16
+func ReadUint16(b io.ByteReader) (uint16, error) {
 	var b1, b2 uint8
 	var err error
 	if b1, err = b.ReadByte(); err != nil {
@@ -47,7 +50,8 @@ func readUint16(b io.ByteReader) (uint16, error) {
 	return uint16(b1) + uint16(b2)<<8, nil
 }
 
-func writeUint64(b *bytes.Buffer, i uint64) {
+// WriteUint64 writes a uint64
+func WriteUint64(b *bytes.Buffer, i uint64) {
 	b.WriteByte(uint8(i & 0xff))
 	b.WriteByte(uint8((i >> 8) & 0xff))
 	b.WriteByte(uint8((i >> 16) & 0xff))
@@ -58,14 +62,16 @@ func writeUint64(b *bytes.Buffer, i uint64) {
 	b.WriteByte(uint8((i >> 56) & 0xff))
 }
 
-func writeUint32(b *bytes.Buffer, i uint32) {
+// WriteUint32 writes a uint32
+func WriteUint32(b *bytes.Buffer, i uint32) {
 	b.WriteByte(uint8(i & 0xff))
 	b.WriteByte(uint8((i >> 8) & 0xff))
 	b.WriteByte(uint8((i >> 16) & 0xff))
 	b.WriteByte(uint8((i >> 24) & 0xff))
 }
 
-func writeUint16(b *bytes.Buffer, i uint16) {
+// WriteUint16 writes a uint16
+func WriteUint16(b *bytes.Buffer, i uint16) {
 	b.WriteByte(uint8(i & 0xff))
 	b.WriteByte(uint8((i >> 8) & 0xff))
 }