Projects

Things I have built

ESP32 Open-Source Wi-Fi MAC

A Wi-Fi MAC layer for the ESP32 written in C on reverse-engineered hardware registers, extending the open-source esp32-open-mac project.

Rewrote the upstream Rust 802.11 MAC (STA/AP, beacon, auth, assoc) in C, then added multi-client AP, intra-BSS forwarding, and runtime SSID and channel changes.
Replaced boolean TX-slot tracking with a mutex-guarded slot state machine, collision retry with random backoff, and a watchdog that reclaims stuck DMA slots. Fixed wrong TX-error register addresses along the way.
Built a PTP-style UDP multicast time-sync service and PTP-scheduled channel hopping with PHY-only fast switching. Result: nodes hop channels on a shared schedule and drive synchronized LEDs.

Source code not public

My M.S. thesis. A system that collects driving data from a car, protects it with post-quantum cryptography, and keeps a verifiable chain of custody.

Raspberry Pi 4 collector reading OBD-II through an ELM327 bridge, 14 PIDs per query loop of about 1.5 s.
NTRU encryption and FALCON signatures on driving data, about 0.525 s for 20 PIDs on the Pi. RabbitMQ to an evidence server with MongoDB, and Hyperledger Fabric chaincode for chain of custody.
Isolation Forest anomaly detection on RPM data at 90.4% accuracy.

github.com/jason19970210/vehicleforensics — Proof-of-concept data logger from the thesis work

A search platform for live streams across YouTube, Twitch and Facebook. It reached 10,000 monthly active users within its first month.

Led an 8-person team and designed the full architecture: crawlers, a Flask API in front of Elasticsearch, MongoDB, and a Node.js frontend on GCP, with crawl jobs scheduled across distributed IoT devices.
Elasticsearch cluster of five nodes plus a master node, with field-boosted relevance (tag and host above title), language detection, and phrase matching with slop for Chinese queries.
Background jobs removed offline streams by comparing each stream's thumbnail with the platform's offline image.

Not public

A robot service system built from scratch on the Android-based Temi robot, with a 4-person team I led as architect and developer.

Collects handicapped parking locations from Taipei and New Taipei open data and syncs them to a Google Maps saved list.

Reads shapefile and paged CSV sources, detects WGS84 or TWD97 coordinates, and converts with pyproj. Polygon zones are reduced to their centroids.
Syncs locations to Google Maps with Playwright, scheduled weekly in GitHub Actions.

A small Python tool that scans the local network and reports each host's operating system and MAC address.

Personalized music recommendation using deep reinforcement learning on user behavior.

Not public