[alalonde]

There has been a proliferation of realtime collaboration within code editors because the underlying data model (a string!) is so simple. As you mentioned, you would need to define a sufficient protocol encapsulating the common functionality between code editors along with defining which aspects would be shared and broadcasted vs kept private (e.g. an independent vs "follow" mode).

The data model could easily be defined in Convergence. Implementation-wise, the primary limitation would be that at the moment we only offer a javascript/typescript client. I haven't explored the VSCode base but I know it was written in TS and provided as a "native app". We do have an example of Convergence running in node.js (NWJS).