The documentation team does not maintain the NixOS Wiki. Here’s some information on that. It’s a community resource running on very outdated insecure software, and the admin is unresponsive. @Mic92 keeps backups just in case.
The source of truth for any documentation should be as close to the actual code as possible. If you want to contribute something and don’t know where to put it, the document linked above should provide some general guidance. Please reach out to the documentation team for details.
With NixOS the problem is that documentation doesn’t really have maintainers and it’s not very well structured overall, so it could be tricky to merge substantial changes. The documentation team unfortunately doesn’t have the capacity to deal with that right now, and our call for maintainers is still valid.