I'd been using Venmo with my friends for a while, but the lack of good support for phones without Google Play Services and eventual removal of their web app lead me to stop using it altogether. My alternative solution was to start paying people back for things using crypto, proxying through the ever-patient Justin Torre for anyone who didn't have time to put up with my bizarre technology choices (i.e. literally everyone else).
Eventually Justin had had enough, so I presented an ultimatimum - we could solve all the problems with cryptocurrency UX so that our friends could finally be convinced to use it, or I would reject society and embrace financial freedom on my own out in the wilderness.
Somehow we ended up with the first option (yes, I'm surprised too).
So, together with him and Inga Wei - a talented electrical engineer who happens to also be amazing at designing user interfaces - we began building out a proof of concept. We've all worked together in the past with great success, so I knew this would turn out great.
Flutter seemed like the best way to build a cross-platform UI without touching any JavaScript. Solana is a lightning fast blockchain with basically negligible transaction fees. And... you know how much I love Rust already. Thus, our tech stack was born.
Also, there happened to be a Solana hackathon going on at the time, which was a neat opportunity to get a bit more exposure and maybe win some prizes.
We got the solana-client crate working on mobile platforms for the first time, tried a whole bunch of Flutter to Rust binding template projects (and made some improvements of our own), and filed even more issues with the Solana Pay spec (of which we made an alternate implementation, too!).
We squashed a whole bunch of chaotic rapid prototyping, but the rest is (git) history.
We invested a ton of time into this project, and I'm super pleased with the result. Solstice Pay is now a real, usable social payments app that you can use instead of Venmo on any desktop or mobile platform.
If you're curious about the mission behind Solstice Pay, I've done plenty of writing about it on the project's website. We also produced a really neat pitch and demo video to submit to the hackathon judges. I highly recommend giving it a watch if you have a spare three minutes; you won't be disappointed.
I'd really like to see a decentralized, interoperable payments system get some mass adoption. Solstice Pay might be our best way to make that happen. It's totally free to use, there's no analytics, you don't need to make an account (we don't even have servers!), and the code is GPLv3 so it'll be open source forever. If this sounds like a future you'd like to be a part of, I'd love to have your feedback on the app!