Fork OpenUtau and develop a new editor

Overview

This page describes the minimum set of changes required when forking OpenUtau and distributing a new editor.

Several OpenUtau-based editors have recently been released without modifying application identifiers, installer settings, update sources, or configuration storage locations. As a result, users have encountered issues such as:

OpenUtau settings being overwritten by a forked editor OpenUtau becoming unable to start due to incompatible configuration files Installation and uninstallation information being overwritten File associations being unexpectedly changed Forked editors updating from the official OpenUtau release channel

The purpose of this document is to help developers avoid these conflicts and ensure that forked editors can coexist safely with the official OpenUtau installation.

This page focuses on identifying the locations that should be reviewed and modified before distributing a forked editor. Some items are required to prevent conflicts, while others are recommended to improve identification, branding, and user experience.

This document assumes the following coexistence model:

Voicebanks may be shared with OpenUtau. External tools and dependencies may be shared with OpenUtau. User preferences, application settings, installer identifiers, and update channels must not be shared with OpenUtau.

Following the recommendations in this document helps prevent user environment corruption and reduces support issues caused by conflicts between OpenUtau and forked editors.

Modification Procedures

Modification List

Category	Modification Target	Priority	Reason
Settings Storage	PrefsFilePath in PathManager.cs	Mandatory	To prevent corruption and startup failure caused by sharing configuration files
Installer Product Name	PRODUCT_NAME in OpenUtau.nsi	Mandatory	To prevent overwriting uninstallation information
Uninstall Key	PRODUCT_UNINST_KEY	Mandatory	To prevent Windows Registry conflicts
Installation Directory	InstallDir "$PROGRAMFILES64\OpenUtau"	Mandatory	To prevent overwriting the original application's installation directory
Shortcut Name	OpenUtau.lnk	Mandatory	To prevent overwriting Start Menu / Desktop shortcuts
Executable Reference	OpenUtau.exe	Mandatory	To prevent launching the wrong application
Updater	UpdaterViewModel.cs	Mandatory	To prevent risks of updating to the original version by referencing original GitHub Releases
.ustx Association	HKCR ".ustx" / OpenUtauFile	Recommended	If not changed, it will hijack the original's file association. Not mandatory as users can change it later
USTX Version	kUstxVersion in USTx.cs	Conditionally Recommended	Only needs modification if the USTX format itself is customized
File Picker Filter	Patterns in FilePicker.cs	Conditionally Recommended	Only needs modification if handling unique extensions or formats
GitHub / Web Links	Wiki / WebSite URL	Recommended	To avoid misleading users to the original project's information
Crowdin workflow	.github/workflows/crowdin.yml	Recommended	To prevent malfunctions in translation synchronization and bot settings
Translation Sync Script	Misc/sync_strings.py	Recommended	Change if managing translation assets independently
Splash Window	Logos and icons in SplashWindow.axaml	Recommended	For visual distinction from the original version
Icon	open-utau.ico	Recommended	For visual distinction from the original version
App Display Name	Assembly Name in OpenUtau.csproj etc.	Recommended	To ensure users do not mistake it for the original version