What were the biggest development challenges?
The biggest challenge wasn't so much the development at all, but the interactions with Lightning tools. When I was trying to implement WebLN (a web standard for browser plugin lightning payments), I had a hard time finding things that supported c-lightning. Seems like a lot of tools/wallets in this space support LND instead of c-lightning. I was about to give up on trying to implement WebLN until fiatjaf (another hackathon participant) pointed out that he made a c-lightning WebLN compliant plugin (kWh), which worked out really well.
What operational challenges have you run into since launch?
I've never been the strongest at design and frontend in general, but I'd have to say that Lighting Channel management has been pretty challenging since launching. Luckily, with BTCPayServer, setting up a production level Lightning Node was easy, but since I am using c-lightning instead of LND, I miss out on a lot of channel management features like Loop Out. I have some ideas to bring more liquidity channels to my Lightning Node, without relying on people to open channels with me directly (though there have been a couple kind souls that have already!), but in general it hasn't as easy to deal with so far.
What are your plans for the project post hackathon?