Background
Devcon[nect] uses Pretix for ticketing, along with the pretix-eth-payment-plugin to accept Ethereum payments.
This plugin has gone through many iterations, most recently using 3cities for Devcon 7; see DIP-37. However, 3cities has been discontinued, so we need a new solution.
Meanwhile, Ethereum is rapidly improving. We have one-cent, one-second transactions. Stablecoins are a key instrument of global permissionless commerce. Friction between the growing set of apps, chains, and coins remains a challenge.
We’ve built Daimo Pay, an open source SDK to accept any chain on any coin. We would like to integrate Daimo Pay into Pretix to provide universal checkout.
Our goals for this proposal are twofold:
- Make it as easy as possible for attendees to buy a ticket. In our ideal world, everyone attending Devconnect this year would buy a ticket on Ethereum rather than fiat rails.
- Raise the bar for real-world Ethereum UX.
Finally, we want to provide a system that’s simple and operationally robust for event organizers.
Proposed solution
In the spirit of “rough consensus and running code,” we’ve built a prototype Pretix integration. See the code here.
40 second demo: Pretix x Daimo Pay | Loom
The Daimo Pay SDK and contracts are open source under BSD and GPLv3, respectively.
Pay uses Intent Addresses to accept payment from any chain, non-custodially, in a single transfer. This allows for a clean user experience that’s also operationally clean for organizers. Funds arrive immediately in a single rollup address, no manual collecting and swapping required.
The underlying intent contracts ensure that any funds sent to a CREATE2 intent address will be swapped, bridged, and forwarded correctly to a specific destination. For bridging, the contracts rely on a combination of CCTP, Across and Axelar.
Pay supports all liquid tokens on major EVM bytecode-compatible rollups, plus Polygon. Users can also pay directly from custodial apps including Coinbase and Binance.
We want to offer a faster and more widely compatible on-chain payment flow than any past Devcon. Our mission is an Ethereum-native checkout that meets or exceeds the experience set by fiat checkouts like Apple Pay or Google Pay. Ethereum is a universal settlement system, so people should be able to pay from anywhere.
Deliverables
We’ll deliver:
- A fully integrated, open source Pretix plugin. See our Github repo.
- Engineering support for setup, validation, and testing
- Technical support before and during the event
- Built-in support for refunds using the open source Peanut Protocol
Cost
Free for users
The goal-state Ethereum checkout is precisely 1:1 for stablecoin payments.
For example, if an item costs $100, then you can pay in a stablecoin such as DAI, USDC or USDT on any rollup by transferring exactly $100.00. Swapping, bridging and associated gas costs are paid by the merchant. This is much less than the ~3% merchants pay on fiat checkout, illustrating Ethereum’s superior properties as a substrate for commerce. Users get a clean, 1:1 experience.
Paying from L1 is not 1:1 — the gas can be far higher, in some cases $5+. Thus, paying a $100 checkout might cost $105 DAI on L1.
The future of Ethereum is rollups. Daimo Pay supports a wide range of chains including L1 (and, optionally at Devcon’s discretion, even Bitcoin and Solana), but the destination is always an Ethereum L2 and the system is optimized for goal-state UX when paying from L2.
Flat rate for Devcon
Daimo Pay charges 1% on payments. This covers integration, running fast relayers, and all swap/bridge/gas costs described above.
There will be no additional costs. Engineering and technical support are included for free.
Timeline
We can have a production-ready plugin ready this month (February 2025). We have an end-to-end working prototype already. See repo above.
We plan to integrate our plugin with other events using Pretix for ticketing. (If you are running such an event, please reach out!) This will ensure production test mileage ahead of the Devconnect ticket launch.
Conclusion
If this collaboration is successful, we will see:
- A delightful and robust ticketing system for Devconnect
- A clean and operationally smooth payment solution for future Devcons
- Proven success, freeing future events to run entirely on-chain
Links and additional information
Pretix website pretix – Reinventing ticket sales for conferences, festivals, exhibitions, ...
Previous payment plugin GitHub - FreePay/pretix-eth-payment-plugin at switch-to-3cities
Prototype Daimo Pay plugin GitHub - daimo-eth/pretix-eth-payment-plugin: An Ethereum payment plugin for Pretix
Daimo Pay https://pay.daimo.com
Daimo Pay SDK codebase GitHub - daimo-eth/paykit: One-click crypto
Intent Addresses Intent Addresses - HackMD