diff --git a/README.md b/README.md
index 21e825d..4b46328 100644
--- a/README.md
+++ b/README.md
@@ -28,4 +28,4 @@ MIT
 [tlstunnel]: https://sr.ht/~emersion/tlstunnel/
 [PROXY protocol]: https://www.haproxy.org/download/2.3/doc/proxy-protocol.txt
 [mailing list]: https://lists.sr.ht/~emersion/public-inbox
-[issue tracker]: https://git.sr.ht/~emersion/tlstunnel
+[issue tracker]: https://todo.sr.ht/~emersion/tlstunnel
diff --git a/server.go b/server.go
index fd2d7c8..e910889 100644
--- a/server.go
+++ b/server.go
@@ -15,6 +15,10 @@ import (
 	"github.com/pires/go-proxyproto/tlvparse"
 )
 
+type conn struct {
+	downstream, upstream net.Conn
+}
+
 type Server struct {
 	Listeners map[string]*Listener // indexed by listening address
 	Frontends []*Frontend
@@ -24,6 +28,8 @@ type Server struct {
 
 	ACMEManager *certmagic.ACMEManager
 	ACMEConfig  *certmagic.Config
+
+	conns map[*conn]struct{}
 }
 
 func NewServer() *Server {
@@ -76,10 +82,16 @@ func (srv *Server) Start() error {
 	return nil
 }
 
+func (srv *Server) Close() error {
+	
+}
+
 type Listener struct {
 	Address   string
 	Server    *Server
 	Frontends map[string]*Frontend // indexed by server name
+
+	ln net.Listener
 }
 
 func newListener(srv *Server, addr string) *Listener {
@@ -105,6 +117,8 @@ func (ln *Listener) Start() error {
 	}
 	log.Printf("listening on %q", ln.Address)
 
+	ln.ln = netLn
+
 	go func() {
 		if err := ln.serve(netLn); err != nil {
 			log.Fatalf("listener %q: %v", ln.Address, err)
@@ -114,6 +128,10 @@ func (ln *Listener) Start() error {
 	return nil
 }
 
+func (ln *Listener) Close() error {
+	return ln.ln.Close()
+}
+
 func (ln *Listener) serve(netLn net.Listener) error {
 	for {
 		conn, err := netLn.Accept()