Help the Watthr fish fill his tank. $1 = 1 liter of water. A sales exercise disguised as a joke.
1d
to build the product
3
major pivots (NFT, narrative, UX)
36
Solidity tests written then discarded
The problem
A developer can ship a product in a day with AI. The real missing skill is knowing how to sell. I set myself a goal: learn to sell through practice. Hardest case chosen: convince people to buy something useless. If that works, selling a real product becomes a simpler problem.
The approach
Minimalist PWA with an animated fish in an aquarium that fills with each purchase. $1 = 1 liter. The level rises in real time for all visitors via Upstash Redis. The product was built in one day. The real work: finding the right narrative angle, the right copywriting, the right purchase mechanic.
Key decisions
NFT on Base blockchain, then completely abandoned
The project started in Solidity with WalletConnect, Crossmint, a bonding curve and 36 Foundry tests. Abandoned in favor of Stripe: less friction, accessible to everyone, zero wallet required.
Narrative pivot: drinking water → AI footprint
Originally the concept was charitable (funding water access). Pivoted to an educational angle: AI consumes up to 700,000 liters to be trained, the fish represents this cost. More legally honest, more viral.
Counter removed, visual aquarium instead
The water level rises visually with purchases, no number displayed. The fish swims freely. More immersive, more engaging than a liter dashboard.
Stack
What I learned
The real skill for a SaaS dev in 2025 is no longer coding fast, it's distributing. This project taught me more about copywriting and purchase psychology than any course. And sometimes the best technical decision is to throw everything away and restart with something simpler.