Scaling Frontend at Perk with Giorgio Polvara | Monolith to Microfrontends, Vite, Zod

What does it actually take to scale a frontend from 15 people in a converted flat to a 1,800-person unicorn, and then migrate the whole thing to microfrontends without breaking anyone's week?

In this episode, Dan sits down with Giorgio Polvara, Staff Engineer at Perk (formerly TravelPerk) and the original creator of @testing-library/user-event (1M+ weekly npm downloads). Giorgio joined TravelPerk as employee #15, set up the frontend foundations that still power the product today, left to try engineering management at Toptal, realized he missed building, and came back as Staff.

They get into the microfrontend migration that replaced a monolithic React app with vertically-split single-page apps served at the infrastructure layer, the rebrand that changed the name, domain, logo, and colors simultaneously, and the philosophy that ties it all together: you're not building features, you're improving a system that happens to produce features.

Key Topics:

- Scaling a frontend team from 7 engineers to a full platform tribe

- Why 20% refactoring time is the wrong model

- Monolith to microfrontends: SingleSPA vs the vertical-split architecture they built

- Managing shared dependencies with pnpm, Syncpack, and Vite plugin packages

- Contract testing with Pact vs runtime schema validation with Zod

- Rebranding an entire product behind a feature flag, without leaking the design

- Why Giorgio tried engineering management and went back to IC

- Staff engineer advice: propose five solutions, expect one to land

🔗 FOLLOW GIORGIO

💼 LinkedIn: https://www.linkedin.com/in/polvara

🐙 GitHub: https://github.com/Gpx

🌐 npm: https://www.npmjs.com/package/@testing-library/user-event

🎙️ FOLLOW & SUBSCRIBE

📸 Instagram: https://www.instagram.com/senorsatscale/

📸 Instagram: https://www.instagram.com/neciudev

🎙 Podcast URL: https://neciudan.dev/senors-at-scale

📬 Newsletter: https://neciudan.dev/subscribe

💼 LinkedIn: https://www.linkedin.com/in/neciudan

💼 LinkedIn: https://www.linkedin.com/company/senors-scale/

📚 ADDITIONAL RESOURCES

- A Philosophy of Software Design by John Ousterhout

- Out of the Tar Pit (Moseley & Marks)

- No Silver Bullet (Fred Brooks)

- @testing-library/user-event: https://www.npmjs.com/package/@testing-library/user-event

- SingleSPA: https://single-spa.js.org

- Vite: https://vitejs.dev

- Pact (contract testing): https://pact.io

- Zod: https://zod.dev

#staffengineer #microfrontends #frontendarchitecture #perk #travelperk #reactjs #softwarearchitecture #engineeringleadership #devtools #softwaredesign #senorsatscale

💬 How does your team handle the tension between shipping features and keeping the system healthy? Drop a comment 👇