H. Zhang

Sheet 02 · Assemblies & details

Projects

Two things I am building now, in detail — and the professional work that came before them.

Part 01 · Founder · 2025 — now · Live, 30+ users nextloom.ai ↗

nextloom.ai

An AI-powered job search assistant for software engineers. It finds relevant roles, tailors the resume and cover letter for each one, helps prepare for interviews, and applies through each company’s own hiring system. I designed the product, architected the system, built it and run it — alone.

Fig. 1 — nextloom.ai architecture
Problem
Applying well is slow: every role wants a tailored resume, a cover letter and a different application form.
Approach
Stateful LLM workflows draft the materials; native ATS APIs submit them first, with a paid layer only where no API exists. A person approves what goes out.
Key decisions
LangGraph with PostgreSQL checkpoints so long workflows resume safely · DDD and CQRS-style separation to keep the domain clear · Effect.ts for typed errors across a pnpm monorepo.
Stack
TypeScript, Hono, Effect.ts, LangGraph, LangChain, PostgreSQL, Vercel
Status
Live, 30+ users
Part 02 · Open source · v0.9.0 · 2026 GitHub ↗Docs ↗

Lingtai

A self-hosted tool that runs a repeatable coding-agent loop on your GitHub issues. It picks up labeled issues one at a time, has an agent work each one in an isolated worktree, runs your repository’s checks, and lands work that passes. When a run needs a person, it stops and records why.

Fig. 2 — Lingtai run loop
Problem
Coding agents are useful, but running them unattended on a real repository needs structure, isolation and a clear stop condition.
How it works
lingtai init → ticket new → doctor → start. A local board shows queued, running, waiting and landed work.
Guardrails
One worktree per run, a filtered environment and a recording hook; optional human approval before merge; honest list of known limitations.
Stack
CLI for macOS and Linux, SQLite by default or Postgres, GitHub App
Status
v0.9.0, first public release (Aug 2026)
Part 03Oracle
Helium

Docker containerization platform and CLI, built solo from idea to adoption. Multiple product teams, 800+ developers; setup from 2+ hours to 15 minutes.

Part 04Oracle
LLM-as-judge

Evaluation platform for chatbot response quality, built solo. Phase 1 in production; significantly increased user trust in LLM results.

Part 05Fuhu
Event-sourced user management

Cassandra event store with replay audit trail for the Nabi platform — 1M devices, 2M child profiles. Led a team of 6.

Part 06Fidelity International
First iOS investment app (UK)

Led development of Fidelity’s first iOS investment application for the UK market.

Part 07Neusoft · China Unicom
Partner relationship management

PRM platform and service provider management system. Led a team of 10.