diff --git a/gbn/gbn_client.go b/gbn/gbn_client.go
index 6cb43b27..dff43545 100644
--- a/gbn/gbn_client.go
+++ b/gbn/gbn_client.go
@@ -41,13 +41,17 @@ func NewClientConn(ctx context.Context, n uint8, sendFunc sendBytesFunc,
 
 // clientHandshake initiates the client side GBN handshake.
 // The handshake sequence from the client side is as follows:
-// 1.  The client sends SYN to the server along with the N value that the
+//  1. The client sends SYN to the server along with the N value that the
 //     client wishes to use for the connection.
-// 2.  The client then waits for the server to respond with SYN.
+//  2. The client then waits for the server to respond with SYN.
+//
 // 3a. If the client receives SYN from the server then the client sends back
-//     SYNACK.
+//
+//	SYNACK.
+//
 // 3b. If the client does not receive SYN from the server within a given
-//     timeout, then the client restarts the handshake from step 1.
+//
+//	timeout, then the client restarts the handshake from step 1.
 func (g *GoBackNConn) clientHandshake() error {
 	// Spin off the recv function in a goroutine so that we can use
 	// a select to choose to timeout waiting for data from the receive
@@ -94,7 +98,10 @@ func (g *GoBackNConn) clientHandshake() error {
 		}
 	}()
 
-	var resp Message
+	var (
+		resp    Message
+		respSYN *PacketSYN
+	)
 handshake:
 	for {
 		// start Handshake
@@ -142,8 +149,10 @@ handshake:
 			}
 
 			log.Debugf("Client got %T", resp)
-			switch resp.(type) {
+			switch r := resp.(type) {
 			case *PacketSYN:
+				respSYN = r
+
 				break handshake
 			default:
 			}
@@ -155,7 +164,8 @@ handshake:
 	}
 
 	log.Debugf("Client got SYN")
-	if resp.(*PacketSYN).N != g.n {
+
+	if respSYN.N != g.n {
 		return io.EOF
 	}
 
diff --git a/gbn/gbn_conn.go b/gbn/gbn_conn.go
index ab52bd69..b6108053 100644
--- a/gbn/gbn_conn.go
+++ b/gbn/gbn_conn.go
@@ -97,7 +97,7 @@ type GoBackNConn struct {
 	pongTicker *IntervalAwareForceTicker
 	pongWait   chan struct{}
 
-	ctx    context.Context
+	ctx    context.Context //nolint:containedctx
 	cancel func()
 
 	// remoteClosed is closed if the remote party initiated the FIN sequence.
diff --git a/mailbox/server.go b/mailbox/server.go
index a0a820b0..f810fbc8 100644
--- a/mailbox/server.go
+++ b/mailbox/server.go
@@ -26,7 +26,7 @@ type Server struct {
 
 	sid [64]byte
 
-	ctx context.Context
+	ctx context.Context //nolint:containedctx
 
 	quit   chan struct{}
 	cancel func()