Modularsamples has released version 0.7.1 of Oi, Grandad!, a free software synthesizer instrument currently available for Mac only.
Built with HISE, the synth features 4 independent granular voices with extensive controls, 12 modulation sequencers and tracking modulation. The granular synth includes a drone button for sustained playback, and per-voice delay.
Oi, Grandad! comes in VST3 and AU plugin formats for macOS. Windows and Linux versions may become available in future updates.
More information: Modularsamples