// the find
juce-framework/JUCE
JUCE is an open-source cross-platform C++ application framework for desktop and mobile applications, including VST, VST3, AU, AUv3, LV2 and AAX audio plug-ins.
JUCE is the de facto C++ framework for building cross-platform audio plugins (VST3, AU, AUv3, AAX, LV2) and their hosts, plus general desktop/mobile GUI apps. It's for C++ developers building audio software professionally, not hobbyists dabbling in DSP for a weekend.
Single codebase targets every major plugin format and host platform (macOS, Windows, Linux, iOS, Android) — that's normally months of platform glue code avoided. The juce_dsp module ships real building blocks (FFT, convolution, IIR/FIR filters, oscillators) instead of leaving you to reimplement them. CMake support is now first-class, not bolted on, so you're not forced into the Projucer GUI tool to manage a build. It's genuinely battle-tested — this is what a huge share of commercial plugins in the wild are actually built on.
Dual-licensed AGPLv3/commercial, and AGPL is a non-starter for any closed-source plugin, so most real users end up needing a paid commercial license whose pricing isn't disclosed anywhere in the repo. The framework is large and compile times are genuinely rough, especially for someone's first plugin project. AAX support requires going through Avid's developer program and PACE's signing process — a bureaucratic chain that has nothing to do with code quality but will stall anyone wanting Pro Tools compatibility. There's no prebuilt Projucer binary in the repo, so step one for newcomers is building JUCE's own tooling before you can build anything else.