Volodymyr was tired of getting soaked. In his home country, if you checked the weather you knew what the next hours would bring. If it was gonna rain you took rain gear. If it was sunny you could enjoy it. Nice and consistent. Reliable. In his new country it was chaos. You could walk out the door into blazing sun and five minutes later you’d get drenched. The locals, the cool locals, managed to look cool getting drenched. He’d never get that. There are RainRadar apps which give an approximation. But they aren’t granular enough. Sometimes there’d be no precipitation in the scan and he’d still come into work dripping. After showing up at a few meetings looking bedraggled, eliciting comments from comedian colleagues, Volodymyr decided that he had an itch to scratch. He knew that the weather service provided realtime data and he figured he only needed two parameters: nearby precipitation and wind direction. When he accessed the weather site he found a list of data feeds. They were all realtime and geofenced with minute frequencies. Volodymyr’s spine tingled. This was high quality data.

As a civil servant Fritz prided himself on being up to speed. In his research department he was responsible for the finances. They had a lot of obligations and subscriptions. The researchers accessed data every day, often in real-time, and most of the sources cost money. This was particularly true of the streaming data. The entities that offered the data never did it gratis because of the freerider problem. Students, data dilettants and the public would overwhelm the servers, many just letting the data flow. So all the data providers charged something for the data streams, even if it was a minor amount, just to act as a filter. Fritz would setup steaming payments to pay for the streaming data. He coupled each payment to the data flow. If for some reason the data stopped the payment would stop too. Likewise, when researchers went home for the day and stopped using an app, they would turn off the stream so as not to waste bandwidth. The payment would stop too. His department used Superfluid for payments. In order to start a stream it was necessary to post a buffer bond, equal to four hours of stream time. Each subscription also had to have a reserve of currency available for the stream. As a result the reserves added up to a sizable amount. All that cash was sitting in a wallet, doing nothing, when it could be deposited in a DeFi protocol and earn double digit compounding interest.

Kazumi liked to be efficient. At the software company where s/he worked they were known for their efficient code. But they were most concerned about efficiency with time. They had important things to do. There was this Virtual YouTuber... Everyday they took a tram to the office, and twice a day they didn’t want to wait. The tram company provided an app where you could see what time a tram was supposed to arrive. But that didn’t mean it would. Kazumi liked it when they walked out the door and the tram was pulling up when they arrived at the stop. When an update to the tram app arrived they noticed that the tram company, which viewed itself as a public good, announced real-time tram telemetrics from each tram’s GPS. The data was available via an API. Nice. It was time to scratch that itch. Kazumi decided to make a little app so they could always catch the tram with no waiting. The first thing they discovered was that the real-time data wasn’t free. It cost half a cent per hour, which wasn’t much, but they hated subscriptions. They were an endless cash drain. Every time they looked in their crypto wallet they noted the money trickling out. For some of the streams, like their insurance and electricity, they didn’t mind because they were necessities. But the subscriptions for niceties, like music, were really irking.

The ETH[City] conferences are Gatherings. They’re where the urban Guilds and rural Tribes of Ethereum assemble to exchange knowledge. In the after hours they’re festivals, giddy celebrations of the success of the ecosystem. Coincidentally I was on a team that just completed the ETHOnline hackathon (with @tgrykias @eurvin and @bidah). Our project, Streaming Collateral, won the “Most Futuristic Hack” prize from sponsor Superfluid. That garnered a lot of attention so the timing of ETHLisbon was auspicious. Most of the action happens in the side events. The main event is a hackathon but – as I discovered – if you’re not hacking you’re understandably not welcome. There are thousands of people milling about so the organizers need a filter. On Thursday morning I went for a run along the Lisbon waterfront. Splendid views. There’s UNESCO world heritage architecture everywhere. There was also a LISCON before the main conf which required a ticket and was sold out. But on Thursday I took an Uber to the PieDAO loft and one of the guys gave me his badge so I could get in. Francesco Renzi, the CEO of Superfluid, was at LISCON (with a t-shirt for me) and I wanted to meet him and see the event. It was swarming with devgens. There were booths with known names like 1inch exchange and various protocols. Superfluid didn’t have a booth and Fran wasn’t feeling well. He headed back to his hotel and I missed him. We were messaging via Telegram.

ETHOnline-2021 Project User Story This story has three roles: The Employer is an established company which pays salaries in streaming cryptocurrency. The Employee, Emmy, received an NFT from her company which acts as the anchor for her incoming salary. She stores it in her hardware wallet. The DeFi Site is a Dapp that offers various services, including bridge loans. Suddenly Emmy needed some liquidity. It wasn’t a surprise, she’d been waiting for a specific opportunity. Of course, it arrived right at the moment that most of her savings were locked up in high-yield lending protocols. If she prematurely withdrew she’d pay a penalty.

HackFS-2021 Project User Story In the third decade of the 21^st^ century the global financial system went through a cataclysm. Inflation had gone negative. People had to pay a bank to hold their savings. Money had gone digital. People began storing their cash in their own digital wallets and managing their investments themselves. This is how it worked. This story has four roles: The Employer is a big tech company that pays salaries in cryptocurrency. The Employee, Emmy, is a worker, barely scraping by, but has some savings. The Lender is a somewhat nefarious service that provides bridge loans. The DeFi Site is a nimble startup pushing the envelope of finance.