HupTrade

I built HupTrade — sell an NFT inside a social post. I run Hup (hup.social), a small onchain social network, and selling an NFT I owned meant screenshotting it, linking an external marketplace, and hoping my followers followed the link — my audience is in my feed, but the transaction lived somewhere else. With HupTrade, the post is the point of sale. Pick an NFT from the composer, set a price, publish; followers see the artwork, traits, price, and a Buy button rendered in their timeline. One click settles everything in a single transaction: payment split, an optional referral share for the reposter who surfaced the listing, and the NFT transfer. It's non-custodial by construction — the token never leaves the seller's wallet; the contract only holds approval rights and re-verifies ownership at settlement, so a stale listing can never move a token. One Solidity contract supports ERC721 and LSP8 collections, priced in native coin, ERC20, or LSP7 tokens, with ERC2771 meta-transactions and burner session keys so listing feels like posting. Live on Monad mainnet, indexed by our open event indexer, running inside hup.social today. What I learned: making commerce feel native to a feed is mostly a latency problem — on Monad, list/buy/cancel confirm fast enough that selling an NFT genuinely feels like publishing a post. Referral shares turn distribution (reposts) into an incentive, which is exactly how a social feed should sell things. And on the way I learned Monad's gas model the hard way: wallets that give up on failed gas estimation hit Monad's strict per-transaction gas cap, so honest pre-flight simulation in the UI matters more here than on other EVM chains.