About Warren de Leon
I'm Warren de Leon, a Software Engineering Manager. I lead mobile teams and I still work in the codebase, mostly React Native.
Everything I write is below. It comes out of work I have actually done: React Native architecture, testing, mobile security, state management, Module Federation, and how to run a hiring process that doesn't waste everyone's time. Build-alongs and post-mortems, not think-pieces.
18 posts 4 series 159 min of reading
Everything I've written
18 posts, newest first.
2026
- 27 July Who owns what: boundaries, teams and coupling in a federated React Native app 16 min read
- 20 July One shared store: server state across federated remotes in React Native 15 min read
- 13 July Tags vs query keys: a small API difference that changes how teams coordinate 5 min read
- 6 July Server state and client state: why React apps need two libraries 5 min read
- 29 June The contract package: a versioned seam between federated remotes in React Native 12 min read
- 22 June The host shell: federated remotes as tabs in React Native 7 min read
- 15 June The shared-singleton contract in React Native Module Federation 7 min read
- 8 June Your first federated remote in React Native 7 min read
- 1 June Why Module Federation in React Native 7 min read
- 25 May Why I use feature-first project structure in React Native 8 min read
- 18 May Detox + Cucumber BDD for React Native E2E testing 10 min read
- 11 May React Native token storage: AsyncStorage vs SecureStore 7 min read
- 4 May Setting up MSW v2 in React Native 10 min read
- 27 April I built an app the hiring panel will never open 9 min read
- 20 April How to write a take-home tech test that candidates actually want to do 8 min read
- 13 April How I designed a tech test scorecard that works from Graduate to Senior 9 min read
- 6 April How to pass a React Native tech test 8 min read
- 29 March Why I redesigned our React Native tech test in my first week 9 min read