Jh W

Full-stack engineer with 6+ years shipping production systems solo and leading small teams — from ERP platforms and AI products to developer tooling. Built end-to-end type-safe systems, reverse-engineered undocumented protocols and file formats to unblock integrations, and created and maintain an open-source Rust text editor used daily in my own workflow.

Comfortable owning a stack top to bottom: infrastructure, backend, frontend, and the messy edges in between.

Full-Stack Software Engineer at Exec (2025-07 – 2026-03)

• Built and maintained playback video generation for roleplays, including real-time AI avatar integration with Tavus.
• Engineered an FFmpeg video-composition pipeline to composite live webcam feeds with AI avatar streams, PDF sharing, and screen sharing — resolving audio/video sync issues along the way.
• Shipped Django/React features including a pausable webcam with canvas compositing and Loom-style recording with chunked uploads to AWS S3.
• Wrote AST-based codemods with LibCST to refactor the Python/Django codebase for type-checkability, making Service classes type-safe at both declaration and call sites.

Full-Stack Software Engineer at Grace (2024-07 – 2025-07)

Sole engineer (alongside a product designer and UI/UX designer) owning the entire stack: Django backend, SwiftUI frontend, and Render infrastructure.

• Built a user memory system ahead of the mainstream LLM-memory trend — archival memory in Postgres retrieved via OpenAI embeddings, plus a working memory layer combining rolling summaries with persistent user traits.
• Built a periodic message-summarization pipeline to support effectively infinite-length conversations.
• Took the product from another engineer's foundation to production, independently — and used Nix + Docker to unify dev, CI, and deployment.

Founding Software Engineer at Didian (2019 – 2024-07)

• Built full-stack ERP applications from scratch (Node.js, TypeScript, GraphQL, PostgreSQL, MongoDB, AWS), including client- and internal-facing dashboards for managing property transactions.
• Executed a gradual, zero-downtime migration of a large portion of the database from MongoDB to PostgreSQL, and introduced a TDD culture to the team.
• Built a custom AST refactoring tool (TypeScript ESLint parser) to enforce GraphQL naming conventions, and an internal GraphQL backend type-codegen tool delivering end-to-end type safety from database → resolvers → React frontend — filling a gap with no existing backend equivalent.
• Reverse-engineered a mobile app's private API via decompilation to enable live property-price scraping, and reverse-engineered a proprietary FirebirdDB schema from a Malaysian accounting system's blob files with zero official documentation.
• Migrated dev/CI/production to Docker, led and trained 10+ interns (including two who built a visual PDF form-mapping editor), and gave repeated engineering talks at UTAR.

Bachelor of Software Engineering in Software Engineering – Universiti Tunku Abdul Rahman (UTAR) (2019)