In ascending order of effort:
We greatly appreciate donated data from existing forums to improve the migration and its testing (using partial, anonymized records). A complete database dump is best way to do this. We protect privacy, but you're welcome to anonymize personally-identifiable information first. Willing to sign an extremely narrow NDA for the purpose if necessary. Contact lincoln@icrontic.com.
Start a discussion if you've hit a problem, including as much detail as possible and any error message or logs available. We don't currently maintain a formal issue tracker.
Did you successfully use Nitro Porter? Start a discussion to tell us all about it! What platforms were you migrating between and how much data was involved? Was it confusing at all?
Send a pull request with a proposed fix! It's greatly appreciated. Please document your understanding of the change, it makes review much easier! Try using conventional commits for a nicer changelog.
Check the developer guide for info on extending Nitro Porter to support a new source or target. It's pretty straightforward! We'll help clean it up if you run into challenges, just get the first draft up in a PR.
Check the maintainer guide for doing advanced work on the core of this project. It currently needs integration tests setup and could use a number of additional database connectors configured. More aspirations are articulated in the informal roadmap. If you're taking on this level of work there are higher expectations, but Linc is happy to help guide.