Haitian Liu
Someone with high agency.
Working on
I build 2 things at TikTok: Sites, TikTok's own internal tool where agents build anything from a quick demo page to a production back office, and the durable cloud agent our operations teams work with.
- Plans first, you approve
- Works in a cloud sandbox
- Survives a server restart
- Waits for you, then resumes
- Shows results as widgets
- Own agent
- Database
- File storage
- Scheduled tasks
- MCP/WebMCP
- Analytics
- Logs
- Env variables
- Test environments
- One-click rollback
- Members & roles
- Service accounts
- Employee sign-in
- Internal data
- Lark (TikTok's Slack)
- AI & video models
Like Lovable, but inside TikTok: anything from a quick HTML page for a demo to a production operations back office. Local agents such as Codex, Claude Code, and Doubao Work build Sites through the Sites plugin, and our cloud agent can build them too. Every Site is wired into TikTok's internal platform, including Lark (TikTok's Slack), and every Site is also a ChatGPT plugin: it serves its actions over MCP, and over WebMCP to agents in the browser.
The agent TikTok's operations teams work with, built to finish long runs: it plans before it acts, survives restarts, and waits for a person when it needs one. We took it from a LangChain prototype through CodeAct on OpenHands to production on Suna's framework.
Why I went all in on agents
In early 2025 I paid for Devin, and it changed how I saw AI: not just models, but agents that do the work. Agents were something a software engineer could build, so I left TikTok's campaign work and went all in, starting with a general-purpose agent. We shipped skills in it before the SKILL.md standard existed. By the spring of 2026 it was clear the race for the general agent had been decided: people start from ChatGPT, Claude, or Doubao Work. So I stopped competing for that entry point and started building what any agent can plug into.
Before agents
I spent 5 years on frontend and graphics: playable campaigns for TikTok events like the Olympics and Squid Game, virtual gifts for TikTok, and growth campaigns for Douyin.
Side projects
A desktop app that turns the AI accounts you already have — ChatGPT, Codex, OpenAI, Anthropic, OpenRouter — into one private, OpenAI-compatible API on your machine.
A Chrome extension that translates web articles and YouTube captions in context, with any OpenAI-compatible model you choose.
A media player for Tesla's in-car browser. Decodes with WebCodecs and draws to canvas, with an AudioWorklet as the playback clock.