Yuhan Li · Portfolio
Backend and LLM application developer, and a contributor to Apache APISIX. I work mainly in Go and Rust, with a focus on API gateways, microservices and observability, and on the engineering of LLM applications.
Technical Skills
- Languages
Go Rust TypeScript C Lua Python- Backend and Infrastructure
gRPC Protocol Buffers Redis PostgreSQL SQLite Qdrant etcd Docker Compose Tokio Axum WebSocket SSE- Observability
OpenTelemetry Prometheus Grafana Tempo- LLM Applications
OpenAI-compatible APIs Semantic caching RAG MCP Tool calling Speech-to-text Text-to-speech Vision input- Frontend
React Cytoscape.js
Open Source Contributions
33 pull requests merged · View all pull requests
The management console for Apache APISIX. My changes fix form submission and data conversion paths that dropped or corrupted configuration, and redact plugin secrets in read-only views. They add contract tests that check the resource schemas against the gateway and run the unit tests in CI, improve internationalisation and accessibility, and add features such as a per-route test request and links between related resources.
1 pull request merged · View all pull requests
Fixed standalone mode so that environment variables are resolved before YAML parsing, which preserves the types of configuration values.
2 pull requests merged · View all pull requests
Restored the container padding and the mobile documentation navigation, and pointed each entry of the version picker to that version's landing page.
Projects
Go · gRPC · Qdrant · Redis · etcd · OpenTelemetry · Prometheus
An OpenAI-compatible API gateway for LLMs; existing clients connect by changing only the base URL. Semantic caching over vector similarity (Qdrant or Redis HNSW) answers semantically equivalent requests from the cache, and retrieval-augmented generation can inject knowledge-base context into prompts. Embedding, caching, completion, authentication and RAG run as separate gRPC services with etcd service discovery; the completion service routes across weighted upstream pools with retries and circuit breaking, and is instrumented with OpenTelemetry tracing and Prometheus metrics.
Go · OpenAI API · MCP · bbolt · Bubble Tea
A Telegram chatbot built on LLMs, with streaming replies, multi-turn context and automatic relevance detection in group chats. Long conversations are retained through a sliding window with rolling summaries; the bot calls local tools and remote MCP servers (Streamable HTTP, SSE and stdio) and loads tool schemas on demand to reduce token usage. It accepts voice, image and document input, enforces daily usage quotas per user and per chat with cost tracking, and provides a terminal administration interface over SSH.
Rust · Axum · PostgreSQL · TypeScript · React
A graph explorer for following funds on Ethereum, expanding counterparties step by step from an address, an ENS name or a transaction hash. Transactions open into a fund-flow graph, their token transfers and the full call tree; calls through proxy contracts are decoded with the implementation's ABI, and tokens impersonating listed ones are flagged. The backend runs on the free Etherscan and Blockscout APIs through a rate-limited job queue and a PostgreSQL cache, with Ethereum wallet sign-in and per-user quotas.
Rust · Tokio · Lua 5.4 · mlua
Middleware for Minecraft servers that extends them by managing the server process's standard input and output. Built on the Tokio runtime, it matches log output against precompiled regular expressions and dispatches events to plugins written in Lua 5.4, each isolated in its own sandboxed environment within a single Lua virtual machine. Published on crates.io as mcrstw.
Other Projects
- phoenix Rust
A stack-based programming language in Reverse Polish notation, with compile-time checks, an opcode interpreter and machine-readable diagnostics. - E-ee Go · WebSocket · Protocol Buffers · SQLite
A backend and command-line client for an end-to-end encrypted chat service; the server only relays ciphertext, and all cryptography runs on the client (Ed25519, X25519, ChaCha20-Poly1305).