The EffectStream presale launchpad already handles Cardano L1 payments. This post covers what comes next: a commitment-based presale that settles on Midnight - a Cardano Partner Chain where every block is validated by Cardano SPOs - and lets buyers reserve a spot in multiple campaigns at the same time without locking their funds for any of them.
This is part two of a two-part series on building a presale on Cardano. Part one covered the on-chain contract - how a purchase receipt is enforced so a participation is only recorded if the buyer really paid. This post is about the app on top of it.
Standing up a presale used to mean wiring a sale contract, an indexer, a payment flow, and a UI before you could take a single order. With the EffectStream preorder launchpad, creating a campaign on Cardano comes down to two steps: clone and publish. This post walks through the app built on top of that contract - and the piece that makes the Cardano side genuinely fast: UTxORPC.
A presale (a launchpad / preorder) sells a catalog of items before they exist: a buyer commits funds now, and the project records who bought what so it can fulfil later. The thing you actually want to guarantee is simple to say and surprisingly subtle to enforce: a participation should only be recorded if the buyer really paid for it — the right amount, to the right address, while the sale is open, and (optionally) crediting whoever referred them.
This post is about doing that guarantee on-chain on Cardano, with a small Aiken minting-policy validator that issues a "purchase receipt" only when the payment rules are met — and about where the rest of the presale logic (catalog, prices, conversion rates) lives so the whole thing stays deterministic. The same app also runs the EVM flow, and the Cardano contract is built to be compatible with that EVM presale — same catalog, same referral model, same recorded state — which we'll come back to once the Cardano picture is clear.
NFT launches are complicated. Creators need smart contracts for the sale, a UI for buyers, multi-chain payment support, proof of participation, and fulfillment tracking. We built a full launchpad platform that handles all of this, with EffectStream powering the backend state management and cross-chain payment processing.