Garry Tan

President and CEO of Y Combinator; investor and builder focused on AI-native systems and agent architecture.

Last updated: 2026-04-12

Overview

Garry Tan is president and CEO of Y Combinator (YC). Previously co-founded Initialized Capital and Posterous. Increasingly writes and teaches about practical AI agent architecture, particularly the thin harness, fat skills pattern for building productive AI systems.

Key Ideas

• Thin harness, fat skills — the architecture pattern behind 100x productivity gains; see thin-harness-fat-skills
• Skills as permanent upgrades — codifying every repeated task into a skill file so the system compounds over time
• Self-improving skill loops — using diarization + feedback to rewrite skill files automatically
• References Claude Code source code (accidentally published to npm on 2026-03-31, 512,000 lines) as empirical evidence for the harness-first thesis

Connections

• thin-harness-fat-skills — his primary conceptual contribution in this wiki
• coding-agent — complementary technical framing by sebastian-raschka

Sources

• Thin Harness, Fat Skills — added 2026-04-12