The goal is indeed to open-source it soon. This is mostly a one-person side-project at the moment, like the rest of Pijul (including the library, the binary, the backend Sanakirja, among others). It isn’t really funded at the moment.
If it were open-sourced, in whatever state, that could help build a community around its development, so that it’s no longer a one-person side project!
As I see it, open-sourcing the Nest would very much allow it to become more than a side project, as it allows more people to work on it and improve it.
It’s would be very nice to see this open sourced and allow people to self-host a pijul nest instance.