I collected a couple of these solutions a while ago, There's [https://github.com/mratsim/trace-of-radiance/blob/99f7d85d/trace_of_radiance/support/emulate_classes_with_ADTs.nim](https://github.com/mratsim/trace-of-radiance/blob/99f7d85d/trace_of_radiance/support/emulate_classes_with_ADTs.nim)
Then on nimble [https://nimble.directory/pkg/interfaced](https://nimble.directory/pkg/interfaced) [https://nimble.directory/pkg/shene](https://nimble.directory/pkg/shene) And [https://nimble.directory/pkg/protocoled](https://nimble.directory/pkg/protocoled)
