diff --git a/agents/parse_agent.go b/agents/parse_agent.go
index 289ce06..0a808a8 100644
--- a/agents/parse_agent.go
+++ b/agents/parse_agent.go
@@ -2,7 +2,6 @@ package agents
 
 import (
 	. "github.com/QUIC-Tracker/quic-tracker"
-	. "github.com/QUIC-Tracker/quic-tracker/lib"
 	"unsafe"
 	"bytes"
 )
@@ -78,9 +77,9 @@ func (a *ParsingAgent) Run(conn *Connection) {
 							break packetSelect
 						}
 
-						payload, err := cryptoState.Read.Open(nil, EncodeArgs(header.PacketNumber()), ciphertext[hLen:hLen+pLen], ciphertext[:hLen])
-						if err != nil {
-							a.Logger.Printf("Could not decrypt packet {type=%s, number=%d}: %s\n", header.PacketType().String(), header.PacketNumber(), err.Error())
+						payload := cryptoState.Read.Decrypt(ciphertext[hLen:hLen+pLen], uint64(header.PacketNumber()), ciphertext[:hLen])
+						if payload == nil {
+							a.Logger.Printf("Could not decrypt packet {type=%s, number=%d}\n", header.PacketType().String(), header.PacketNumber())
 							break packetSelect
 						}
 
@@ -94,9 +93,9 @@ func (a *ParsingAgent) Run(conn *Connection) {
 
 						off += hLen + pLen
 					case ShortHeaderPacket: // Packets with a short header always include a 1-RTT protected payload.
-						payload, err := cryptoState.Read.Open(nil, EncodeArgs(header.PacketNumber()), ciphertext[hLen:], ciphertext[:hLen])
-						if err != nil {
-							a.Logger.Printf("Could not decrypt packet {type=%s, number=%d}: %s\n", header.PacketType().String(), header.PacketNumber(), err.Error())
+						payload := cryptoState.Read.Decrypt(ciphertext[hLen:], uint64(header.PacketNumber()), ciphertext[:hLen])
+						if payload == nil {
+							a.Logger.Printf("Could not decrypt packet {type=%s, number=%d}\n", header.PacketType().String(), header.PacketNumber())
 							break packetSelect
 						}
 						cleartext = append(append(cleartext, udpPayload[off:off+hLen]...), payload...)
diff --git a/connection.go b/connection.go
index 18d9874..255c857 100644
--- a/connection.go
+++ b/connection.go
@@ -77,7 +77,7 @@ func (c *Connection) SendPacket(packet Packet, level EncryptionLevel) {
 		}
 
 		header := packet.EncodeHeader()
-		protectedPayload := cryptoState.Write.Seal(nil, EncodeArgs(packet.Header().PacketNumber()), payload, header)
+		protectedPayload := cryptoState.Write.Encrypt(payload, uint64(packet.Header().PacketNumber()), header)
 		packetBytes := append(header, protectedPayload...)
 
 		sample, pnOffset := GetPacketSample(packet.Header(), packetBytes)
diff --git a/crypto.go b/crypto.go
index 74e0a90..bcbe0a2 100644
--- a/crypto.go
+++ b/crypto.go
@@ -1,9 +1,7 @@
 package quictracker
 
 import (
-	"crypto/cipher"
 	"github.com/mpiraux/pigotls"
-	. "github.com/QUIC-Tracker/quic-tracker/lib"
 )
 
 var quicVersionSalt = []byte{  // See https://tools.ietf.org/html/draft-ietf-quic-tls-10#section-5.2.2
@@ -62,19 +60,19 @@ type DirectionalEncryptionLevel struct {
 }
 
 type CryptoState struct {
-	Read  cipher.AEAD
-	Write cipher.AEAD
+	Read  *pigotls.AEAD
+	Write *pigotls.AEAD
 	PacketRead *pigotls.Cipher
 	PacketWrite *pigotls.Cipher
 }
 
 func (s *CryptoState) InitRead(tls *pigotls.Connection, readSecret []byte) {
-	s.Read = newProtectedAead(tls, readSecret)
+	s.Read = tls.NewAEAD(readSecret, false)
 	s.PacketRead = tls.NewCipher(tls.HkdfExpandLabel(readSecret, "pn", nil, tls.AEADKeySize()))
 }
 
 func (s *CryptoState) InitWrite(tls *pigotls.Connection, writeSecret []byte) {
-	s.Write = newProtectedAead(tls, writeSecret)
+	s.Write = tls.NewAEAD(writeSecret, true)
 	s.PacketWrite = tls.NewCipher(tls.HkdfExpandLabel(writeSecret, "pn", nil, tls.AEADKeySize()))
 }
 
@@ -96,17 +94,6 @@ func NewProtectedCryptoState(tls *pigotls.Connection, readSecret []byte, writeSe
 	return s
 }
 
-func newProtectedAead(tls *pigotls.Connection, secret []byte) cipher.AEAD {
-	k := tls.HkdfExpandLabel(secret, "key", nil, tls.AEADKeySize())
-	iv := tls.HkdfExpandLabel(secret, "iv", nil, tls.AEADIvSize())
-
-	aead, err := NewWrappedAESGCM(k, iv)
-	if err != nil {
-		panic(err)
-	}
-	return aead
-}
-
 func GetPacketSample(header Header, packetBytes []byte) ([]byte, int) {
 	var pnOffset int
 	sampleLength := 16