Uploaded March 2026 | Updated September 2026, 2 weeks ago

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In this episode of Founder Firesides, YC General Partner Aaron Epstein talks to Sherwood Callaway, founder of Sazabi (P26), who exited his first YC company and is coming back through YC for a second time. Sazabi is an AI-native observability platform that replaces tools like Datadog, letting engineers ask plain-English questions about their production systems instead of digging through dashboards. They discuss why logs are the only telemetry you need, lessons from building a company that didn't play to his strengths, and why maintaining software is AI's biggest untapped opportunity.

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Chapters:
00:00 — Back to YC for a second time
00:24 — The AI tool fixing production bugs
01:36 — “Logs are all you need?”
03:43 — Inside observability at Brex
07:42 — Starting a healthcare startup
12:21 — When the first startup unraveled
17:02 — The insight behind Sazabi
22:51 — Returning to YC
27:00 — Lessons for founders + hiring