Viet Le

Full-stack engineer focused on React/TypeScript systems, specializing in local-first architecture and high-performance UIs. I build web apps that stay fast, work offline, and sync updates across devices.

Tech stack: TypeScript, Next.js (React), tRPC, PostgreSQL, Prisma, Zustand, IndexedDB, Service Workers (PWA), Server-Sent Events (SSE), Cloudflare R2

Featured Project: CardLedger

A local-first Pokémon card portfolio tracker where collectors search 21,000+ cards, manage their collections, and track real-time market value across devices — all with zero loading states and full offline support. What looks like a simple Pokédex-style catalog became an engineering challenge at scale: a 4.9M-row price history table, a custom sync engine, and a $2/month stack that outperforms $100+/month API-based competitors.

• Offline-First Data Integrity: Engineered full offline support and cross-device sync via Service Workers, SSE, and PostgreSQL NOTIFY. Uses LWW timestamps and tombstoned deletes to guarantee no mutation is ever silently lost during network drops. Read the sync engine deep dive ↗
• Zero-Latency Search: Updates results instantly on every keystroke with no pagination across 21,000+ items. Powered by a custom IndexedDB engine with inverted index and dictionary-compressed JSON, achieving ~0.3ms filter latency and sub-2ms full-text search.
• Cost-Optimized Infrastructure: Reduced infrastructure costs from $119–188/month to $2/month by building a dictionary-compression pipeline that shrinks 10MB payloads to ~400KB, publishing versioned static assets via GitHub Actions to Cloudflare R2, and pre-generating AVIF variants for 80,000+ images.