diff --git a/common/auth_token.go b/common/auth_token.go
index a780e1e..85a0c42 100644
--- a/common/auth_token.go
+++ b/common/auth_token.go
@@ -85,8 +85,6 @@ func MarshalNASAuthToken(gamecd string, userid uint64, gsbrcd string, cfc uint64
 }
 
 func UnmarshalNASAuthToken(token string) (gamecd string, issuetime time.Time, userid uint64, gsbrcd string, cfc uint64, region byte, lang byte, ingamesn string, challenge string, unitcd byte, isLocalhost bool, err error) {
-	err = nil
-
 	if !strings.HasPrefix(token, "NDS") {
 		err = errors.New("invalid auth token prefix")
 		return
@@ -143,9 +141,8 @@ func MarshalGPCMLoginTicket(profileId uint32) string {
 }
 
 func UnmarshalGPCMLoginTicket(ticket string) (profileId uint32, issuetime time.Time, err error) {
-	err = nil
-
-	blob, err := Base64DwcEncoding.DecodeString(ticket)
+	var blob []byte
+	blob, err = Base64DwcEncoding.DecodeString(ticket)
 	if err != nil {
 		return
 	}
@@ -155,7 +152,8 @@ func UnmarshalGPCMLoginTicket(ticket string) (profileId uint32, issuetime time.T
 		return
 	}
 
-	block, err := aes.NewCipher(loginTicketKey)
+	var block cipher.Block
+	block, err = aes.NewCipher(loginTicketKey)
 	if err != nil {
 		panic(err)
 	}
diff --git a/common/match_command.go b/common/match_command.go
index 94c6e07..6402d6d 100644
--- a/common/match_command.go
+++ b/common/match_command.go
@@ -560,7 +560,8 @@ func EncodeMatchCommand(command byte, data MatchCommandData) ([]byte, bool) {
 		message = binary.BigEndian.AppendUint32(message, data.Reservation.PublicIP)
 		message = binary.LittleEndian.AppendUint32(message, uint32(data.Reservation.PublicPort))
 
-		if version == 11 {
+		switch version {
+		case 11:
 			isFriendInt := uint32(0)
 			if data.Reservation.IsFriend {
 				isFriendInt = 1
@@ -568,7 +569,7 @@ func EncodeMatchCommand(command byte, data MatchCommandData) ([]byte, bool) {
 			message = binary.LittleEndian.AppendUint32(message, isFriendInt)
 
 			message = binary.LittleEndian.AppendUint32(message, data.Reservation.LocalPlayerCount)
-		} else if version == 90 {
+		case 90:
 			message = binary.BigEndian.AppendUint32(message, data.Reservation.LocalIP)
 			message = binary.LittleEndian.AppendUint32(message, uint32(data.Reservation.LocalPort))
 			message = binary.LittleEndian.AppendUint32(message, data.Reservation.Unknown)
diff --git a/common/misc.go b/common/misc.go
index d640695..1403477 100644
--- a/common/misc.go
+++ b/common/misc.go
@@ -2,9 +2,19 @@ package common
 
 import "reflect"
 
-func MaybeUnused(v ...interface{}) {
+// MaybeUnused is a helper function to mark variables as used to avoid compiler warnings.
+func MaybeUnused(v ...interface{}) struct{} {
+	return struct{}{}
 }
 
+// ShouldNotError panics if the error is not nil.
+func ShouldNotError(err error) {
+	if err != nil {
+		panic(err)
+	}
+}
+
+// ReverseMap takes a map and returns a new map with the keys and values reversed.
 func ReverseMap(m interface{}) interface{} {
 	inputType := reflect.TypeOf(m)
 	inputValue := reflect.ValueOf(m)