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Software engineer & engineering leader in Singapore. Senior Staff @ Meta, ex-Googler. Building and writing about AI agents.
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Senior Staff Software Engineer at Meta · since Apr 2026
Recent writing
All posts →- From Prompt to Context to Harness: Notes on the Agent OS2026-05-27
Coding with AI keeps shifting under us, from prompt engineering to context engineering to harness engineering. A working-through of what a harness actually is, two ways to build an operating system for agents, and a guess at how models might start writing their own skills.
- The Spec Is the Code: A Loop for Agent-Driven Development2026-05-23
When agents write the code, the spec becomes the artifact you actually review. This sketches a spec-exec-eval-bench-improve loop — the format, the agent swarm, and the self-improving harness it would take to make it real — while engaging the spec-driven camp that already named most of the pieces.
- Skills, Tools, MCP, Agents: How I Think About the Pieces2026-03-24
A working taxonomy of the agent stack — tools, MCP, skills, and agents — plus notes on the parts I find more interesting: subagents versus agent teams, and the context- and harness-engineering ideas that seem to decide how far a single setup can scale.