A library that lets Eurorack modules built around Arduino OLED screens run inside VCV Rack with almost no code changes.
The example plugin cycling through drawing demos on a simulated SSD1306.
Firmware for those modules draws to the display through u8g2, which expects a real screen wired to a real microcontroller. This gives it one that is not there. The same drawing code runs against a software renderer instead.
What that buys is one codebase with two destinations. A module can be built as hardware and as a VCV Rack plugin in parallel, from the same source, rather than the plugin being a separate reimplementation that quietly drifts out of step. It also works the other way around: an existing physical module can be ported into the rack without rewriting its interface from scratch.
It is the same instinct as the day job, really, just pointed at synthesizers instead of studios. One codebase, more than one place for it to end up, and no second version to keep in sync.
Here’s a working example.