David Freitag

I’m a senior product-minded engineer who ships TypeScript, React, and Next.js applications with ownership from idea through production. I blend frontend craft and design systems with AI-assisted development (Cursor) under real quality bars.

At Sinclair Digital, I’ve owned features and platform improvements in a large production TypeScript/React codebase—delivery, tests, CI, and design handoff from Figma. I led extensive Jest unit/component testing and Maestro end-to-end mobile testing, optimized CI by reducing test memory pressure, and ratcheted coverage from ~40% toward ~55% with drop-blocking gates. I also architected and built the company’s entire RTK Query infrastructure from scratch and migrated ESLint/Prettier to Biome, speeding up lint/format by 23x.

I rebuilt the company’s shared component system on Gluestack v3 as the org-wide default design system across React Native apps, including theming and consistent component APIs. I instrumented analytics with Google Analytics and ran experiments/gradual rollouts with LaunchDarkly, while leading accessibility fixes across screens and shared components.

Before that, as a founding mobile engineer at Walmart Health, I helped build Next.js / React Native Web prototypes that became core alpha and beta on walmarthealth.com. I shipped production appointment scheduling flows, authored shared React Native library components, and reduced accessibility errors by ~15% through end-to-end implementation.