ReplayChess
Chess history you play, not watch
About
Most chess sites give you a game database or a video. ReplayChess gives you the position. You pick a famous game, jump in at the moment where it was decided, and play the rest yourself against a friend through a private link, a rated opponent from the matchmaking queue, or Stockfish running in your browser. When it is over, the app lines your moves up against the grandmaster's and shows you the first place you went a different way.
Inside: 50+ legends from Morphy to Carlsen with playable famous positions; a 3,600-entry ECO openings encyclopedia, every line playable from its resulting position; real-time clocks, rating-based matchmaking and tournaments; Stockfish as WebAssembly at four strengths; a post-game match rate and divergence report with a practice mode. Installs as a PWA.
Free to play, no ads. The Player plan ($4.99/month or $50/year) unlocks the full catalogue. MIT-licensed on GitHub, built with Next.js 15, React 19, Prisma, Socket.IO and Stockfish WASM.
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FounderPlaybooks.
What other founders did to grow.
2722 dispatches from hundreds of founders, pulled from the week's best podcasts.
speed is becoming the moat right and I think that we kind of live by that... when small teams with driven product-minded engineers and founders fit together with this go fast and ship move then that's where you really start to get harmony and you can deliver bigger results
Speed is the moat: small teams plus founder-mindset engineers compound their edge
ElevenLabs' competitive edge is not just the voice model but the organizational structure that lets them ship improvements faster than any competitor can respond. Small teams, founder-mindset engineers, and a culture where speed is the explicit guiding principle combine into a compounding advantage: the company that learns fastest wins, and learning speed is a direct function of ship cadence. In AI, a quarter of stagnation can cost market leadership.
I started posting 'here's what I'm working on next' — not at launch but throughout the year. People started tagging their friends saying 'this is coming, you need this.' That sustained engagement carried me through dead periods where I had nothing actually ready to ship.
Teasing a coming feature before it ships — not just at launch — is what unlocked momentum
Duffett found that pre-announcing upcoming features (with screenshots or demos of in-progress work) drove more engagement than post-launch announcements. Users who anticipated a feature became advocates before it shipped, tagging others and amplifying reach. This created a predictable engagement cycle independent of release cadence — especially valuable for a solo developer whose shipping pace is irregular.
There's a play for whatever you're stuck on.
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