Episode 7 62 minutes

Open Source at Scale – With Erik Rasmussen

Key Takeaways from our conversation with Erik Rasmussen

Erik Rasmussen

Principal Product Engineer at Attio, Creator of Redux Form & React Final Form

In this episode of Señors @ Scale, host Neciu Dan sits down with Erik Rasmussen — creator of Redux Form and React Final Form, and now Principal Product Engineer at Attio — to talk about building open source at scale, developer experience, and the hidden lessons behind shipping tools other developers rely on.

Main Takeaways from my conversation with Erik:

CRUD never went away.
Underneath every shiny new tool, software often reduces to inputs, a database, and listing results back out.

🛠 Developer experience is the product.
At Attio, “time-to-first-app” is the north star — if you can’t ship a working button in 5 minutes, the SDK failed.

📚 Docs are for AIs now.
Modern documentation is written as much for LLMs as for humans, which means examples and verbosity matter more than polish.

💡 Bundle size is a hidden tax.
Redux Form bloated from feature creep. React Final Form fixed that by going modular and framework-agnostic.

🔒 Secure runtimes matter.
Third-party code runs in Wasm sandboxes, stripped of cookies and the DOM — protecting users while still letting devs build in React.

🧪 Testing unlocks trust.
From unit tests on pure functions to CLI init tests across npm/yarn/pnpm/bun, Erik shows how deep testing builds confidence in SDKs.

📈 Breaking changes break trust.
Deprecation windows aren’t optional — stability is the contract when thousands depend on your library.

👩‍💻 Open source is an on-ramp.
Contributing to libraries teaches not just code, but how to take feedback, communicate clearly, and be part of a developer community.

📚 Recommended Read:

  • Project Hail Mary by Andy Weir (also the author of The Martian)

🎤 Also in this episode:

  • Why React’s free-market chaos beat Angular’s strict framework rules
  • Lessons from XState adoption — and when to rip it out
  • Why Zod is now essential for runtime type safety
  • How Erik went from rejecting his first conference talk to becoming a regular speaker

Episode Length: 62 minutes of open source lessons, developer experience, and frontend scaling stories.

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