diff --git a/out.go b/out.go
index f771ebc..9479e01 100644
--- a/out.go
+++ b/out.go
@@ -78,7 +78,8 @@ func emptyOutData(outpath string) error {
 }
 
 func CopyOut(roomFolders []RoomFolder, outpath string, splash1len, splash2len int) error {
-	inistr := fmt.Sprintf(`[SETTINGS]
+	var inistr strings.Builder
+	fmt.Fprintf(&inistr, `[SETTINGS]
 Sensitivity=6
 Splash1len=%d
 Splash2len=%d
@@ -89,13 +90,13 @@ Splash2len=%d
 		if err != nil {
 			return fmt.Errorf("error copying folder %s: %+v", roomFolder.Path, err)
 		}
-		inistr += roomFolder.Cfg.ToIni()
+		inistr.WriteString(roomFolder.Cfg.ToIni())
 	}
 
 	outini := filepath.Join(outpath, "CF.ini")
 	log.Println("INFO:")
 	log.Printf("INFO: Writing %s", outini)
-	return os.WriteFile(outini, []byte(inistr), FILEPERM)
+	return os.WriteFile(outini, []byte(inistr.String()), FILEPERM)
 }
 
 func copyFolder(roomFolder RoomFolder, outpath string) error {