iPlug2/iPlug2

iPlug2 is a simple-to-use C++ framework for developing cross-platform audio plug-ins and applications. It abstracts audio plug-in logic (IPlug) and a drawing engine/GUI toolkit (IGraphics) to target multiple plug-in APIs with minimalistic code. IGraphics provides a collection of common controls for audio plug-ins using bitmap or vector graphics, with support for NanoVG or Skia backends (including GPU acceleration and HiDPI/scaling). iPlug2 supports CLAP, VST2, VST3, AUv2, AUv3, AAX (Native), Web Audio Module (WAM v1), standalone win32/macOS apps with audio/MIDI I/O, and Reaper extensions. It can compile to WebAssembly via emscripten and targets Windows 8+, macOS 10.13+, iOS 15+, and visionOS 26+. The framework is licensed under a permissive zlib-like license, free for closed-source projects, and is actively maintained with community support via forums and Discord.