Currently midilink only supports Mixxx's non-standard MIDI note mapping and only in one direction (MIDI -> Link). It would be cool to support other MIDI clocks too, e.g. MIDI beat clock, ideally in both directions (would require us to generate a periodic beat output)

Windows does not support virtual MIDI ports (see Boddlnagg/midir#37), therefore users would have to install a custom MIDI loopback driver. We could e.g. add command-line options to configure custom MIDI input/output ports to connect to (instead of creating virtual ports). On Windows, these would be required, while on Unix-like platforms (macOS/Linux), they would be optional and default to the current behavior.

Currently we use a hardcoded quantum¹ of 1 (beat), which means that Mixxx may not be phase-aligned with other apps in the Link session. Therefore it would be cool either have a separate app or a way to trigger a downbeat here.

Just adding few notes, e.g. on how to configure Mixxx with the "MIDI for light" mapping or adding a link to a compatible Link-enabled app like Captivate might be useful.

It would be nice if we could deploy binaries for the supported platforms (macOS, Linux) to GitHub Releases.