Plebeian Market.
The code behind plebeian.market is older code. In the mean time we have transitioned everything to Nostr (NIP-15 for fixed price items, but also auctions - which is beyond NIP-15).
Working on some final touches now before we move plebeian.market to the new version (Nostr based), which is currently available in our staging environment!
All the code is in GitHub, BTW: https://github.com/PlebeianTech/plebeian-market
PS: I am one of the devs behind PM.