diff --git a/wgtester/wgtester.go b/wgtester/wgtester.go
index 0035f05..26988f6 100644
--- a/wgtester/wgtester.go
+++ b/wgtester/wgtester.go
@@ -126,7 +126,7 @@ func (s *Server) Stop() {
 		s.conn.Close()
 	}
 	s.isRunning = false
-	logger.Info(s.outputPrefix + "Server stopped")
+	logger.Info("%sServer stopped", s.outputPrefix)
 }
 
 // RestartWithNetstack stops the current server and restarts it with netstack
@@ -161,7 +161,7 @@ func (s *Server) handleConnections() {
 			// Set read deadline to avoid blocking forever
 			err := s.conn.SetReadDeadline(time.Now().Add(1 * time.Second))
 			if err != nil {
-				logger.Error(s.outputPrefix+"Error setting read deadline: %v", err)
+				logger.Error("%sError setting read deadline: %v", s.outputPrefix, err)
 				continue
 			}
 
@@ -187,7 +187,7 @@ func (s *Server) handleConnections() {
 				case <-s.shutdownCh:
 					return // Don't log error if we're shutting down
 				default:
-					logger.Error(s.outputPrefix+"Error reading from UDP: %v", err)
+					logger.Error("%sError reading from UDP: %v", s.outputPrefix, err)
 				}
 				continue
 			}
@@ -219,7 +219,7 @@ func (s *Server) handleConnections() {
 			copy(responsePacket[5:13], buffer[5:13])
 
 			// Log response being sent for debugging
-			logger.Debug(s.outputPrefix+"Sending response to %s", addr.String())
+			logger.Debug("%sSending response to %s", s.outputPrefix, addr.String())
 
 			// Send the response packet - handle both regular UDP and netstack UDP
 			if s.useNetstack {
@@ -233,9 +233,9 @@ func (s *Server) handleConnections() {
 			}
 
 			if err != nil {
-				logger.Error(s.outputPrefix+"Error sending response: %v", err)
+				logger.Error("%sError sending response: %v", s.outputPrefix, err)
 			} else {
-				logger.Debug(s.outputPrefix + "Response sent successfully")
+				logger.Debug("%sResponse sent successfully", s.outputPrefix)
 			}
 		}
 	}