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Software Engineer · AI Agents & Backend Systems

Longchang Liu

I build reliable AI workflows, backend services, and developer tools, with an interest in the systems beneath them.

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Primary focus AI Agent Engineering
Foundation Java & Backend Systems
Working style Clarity, resilience, iteration
01 / Selected work

One project, end to end.

A system-level experiment in visual perception, action, reflection, and context management.

Project record
Lavis green mascot Watch demo

Lavis: macOS Multimodal AI Agent

A desktop agent that sees the screen, controls mouse and keyboard, and supports voice interaction. The execution loop combines visual perception, autonomous actions, reflection, and context compression.

  • Spring Boot
  • React
  • Electron
  • TypeScript
  • Java
Project detail GitHub
02 / Writing

Notes from the work.

Selected writing on agent infrastructure, operating systems, and production engineering.

Browse all records
2025.07 · AI Agents Prompt Caching: Architecting Low-Latency AI Agents A practical look at latency, inference cost, and cache-aware agent architecture. 2025.03 · Systems OS Internals: The Mechanics of Page Tables Address translation, hardware isolation, and process address spaces in xv6. 2026.01 · Research AI Paper Cuts: mHC A concise reading of recent research, focused on core contributions and engineering implications.

Let’s build something useful.

For engineering roles, open-source collaboration, or a thoughtful conversation about systems and AI tooling.

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