Windhawk
The customization marketplace for Windows programs
...This makes it ideal for end users, power users, and developers who want to adapt apps to their needs — such as adding missing features, improving usability, or automating repetitive tasks — without waiting for the original developers to update the software. The framework provides a clear API for plugins, a friendly editor experience, configuration management, and controls for plugin loading order and dependencies. It also includes a curated repository of community-submitted plugins that add dozens of enhancements for popular applications, which fosters sharing and discovery of useful mods.