A full-stack developer activity platform turning the editor into a logbook — pace, splits, streaks, and leaderboards as rituals of a real sport, applied to code. A VSCode extension captures editor activity in real time; a Hono API ingests and aggregates sessions; a React web app surfaces session detail, streaks, leaderboards, and shareable keyboard heatmap cards.

The extension captures key labels — never key content — across three configurable privacy modes. The API aggregates raw events into session records with pace, line delta, and per-language breakdowns. The Canvas heatmap layer renders per-session key frequency as a transparent PNG exportable in three aspect ratios (9:16, 1:1, 16:9) for social sharing. Redis sorted sets back real-time weekly, monthly, and all-time leaderboards filterable by language.

A production-grade central limit order book matching engine written in Rust, architected for sub-microsecond execution in high-frequency trading environments. Designed around zero-cost abstractions, lock-free concurrency primitives, and memory-mapped persistence with crash recovery guarantees.

Built to match or exceed the performance profile of institutional-grade matching engines. The design eliminates all dynamic memory allocation on the critical execution path, using a pre-allocated arena and stack-pinned message passing throughout. The WAL layer guarantees durability without sacrificing microsecond-level recovery windows, verified end-to-end via HdrHistogram latency measurement under Criterion benchmarks.

A high-performance LLM routing gateway written in Go that cuts inference costs by 91.6% without degrading output quality. Routes requests dynamically using real-time Shannon entropy analysis of token logprobabilities, executes speculative drafts via goroutines, and serves repeated semantic queries from a vector-backed cache layer under 50ms.

The entropy router evaluates token-level confidence distributions from the drafter model before deciding whether to escalate to a capable and expensive model. The semantic cache layer uses vector search to detect repeated queries above a cosine similarity threshold, eliminating redundant inference on cache-accepted responses entirely. Full observability via Prometheus and Grafana covers routing decisions, cache hit rates, and per-model cost attribution.

A multi-agent AI assistant for software engineering workflows, built on a LangGraph orchestration backbone with a FastAPI runtime and ChromaDB vector memory. Handles the full spectrum of developer requests through a 7-agent pipeline with 100ms median response time and 100% test coverage across 245+ cases.

Each agent in the pipeline is scoped to a discrete responsibility: intent classification, repository context retrieval, code analysis, diff generation, review synthesis, test suggestion, and response formatting. LangGraph manages state transitions and conditional routing between agents, enabling complex multi-hop workflows without brittle prompt chaining.

A production-deployed AI branding platform written in Go, generating brand identities through high-concurrency API orchestration. Integrates Google Gemini AI for creative generation with a trust score engine and browser fingerprinting for session security, delivering complete brand packages under 200ms via concurrent goroutine execution. Validated under 2,300+ requests/day via k6 stress testing.

The fan-out architecture dispatches all generative API calls simultaneously at request ingestion, collapsing serial latency chains into a single parallel wait window. Trust scoring evaluates session signals in real time, gating generation behind lightweight anomaly detection before touching paid API quota. Ent ORM enforces strict type safety on the PostgreSQL layer, enabling reliable large-scale brand data synchronization across distributed API sources.

A real-time peer study matching platform serving 400+ active users at FPT University, built on a Socket.IO event bus with PostgreSQL persistence and Redis caching. Engineered to sustain 1,700+ requests per minute under concurrent session load with p50 response times under 400ms.

The Redis layer serves presence state and match candidates from memory, keeping the hot path away from PostgreSQL except for durable writes. Socket.IO manages bidirectional session state across the matching lifecycle, from availability broadcast through confirmation handshake to session teardown. Led 6 engineers through sprint planning and code reviews across the full product lifecycle.

A privacy-first journaling application with end-to-end encryption — thoughts are encrypted on-device before leaving the client, ensuring the server never has access to plaintext content. Daily writing prompts eliminate the blank-page problem and drive consistent engagement.

The encryption model ensures that even a full database compromise exposes no user content — all plaintext remains on the client. The daily prompt system is designed to reduce activation energy for writing, routing prompts through Resend at scheduled intervals to nudge users back into the habit loop.

A brutalist-by-design S3 file storage platform for sharing files and environment configs between machines. Private by default, public on demand — files stay locked to the owner until explicitly toggled, with share links available for public files only.

Files are private by default on upload — private files are owner-only for preview and management, while public files are downloadable by anyone with the file ID. Share links are generated only for public files, keeping accidental exposure impossible by design.