Cardinal is a free and open-source virtual modular synthesizer plugin,
available as CLAP, LV2, VST2 and VST3 audio plugin for FreeBSD, Linux,
macOS and Windows. Plus AU and JACK or Native audio standalone for
some systems. It is based on the popular VCV Rack but with a focus on
being a fully self-contained plugin version.

More specifically, this is a DPF-based plugin wrapper around VCV Rack,
using its code directly instead of forking the project, with the target
of having a proper, self-contained, fully free and open-source plugin
version of Rack. Cardinal contains Rack, some 3rd-party modules and a
few internal utilities all in a single binary. All "Core" modules from
Rack have been replaced by Cardinal equivalents, simplified to better
work for an audio plugin.