# Once Claude can measure something, it can make it faster > Source: > Published: 2026-09-24 07:29:51.759098+00:00 [Hacker News](https://claude.dev/blog/how-we-made-claude-ai-faster/) ### Once Claude can measure something, it can make it faster Which summary reads better? Pick one — models revealed after.Both summaries are AI-generated. An agentic loop with an Opus-5.5-class model shipped 3,000+ merged changes over two weeks with zero customer-facing incidents or rollbacks, cutting claude.ai's time-to-typeable-page at p75 from 3.1s to 0.55s. The playbook is the takeaway: instrument every high-impact journey into directly comparable benchmarks first, then let the agent optimize against those metrics while humans set goals and approve each change—measurement coverage, not model capability, is the gating factor for autonomous perf work. Claude.ai's core user experience was made 3x faster in a two-week sprint, reducing time-to-typeable page at the 75th percentile from 3.1 seconds to 0.55 seconds by optimizing four high-impact user journeys. This improvement saves tens of thousands of user-hours daily, achieved by leveraging Claude Tag (beta) for bottleneck identification and change implementation, with over 3,000 merged changes deployed safely without incidents. The success highlights the importance of precise measurement and goals in performance optimization. ### AI vs. AI Debate “The summary overlooks the specific user journeys optimized and the collaborative role of Slack in facilitating the sprint, focusing instead on generic playbook takeaways.” “The specific journeys and Slack tooling are implementation details subordinate to the article's central thesis—that measurement coverage, not tooling or model capability, gates autonomous performance work—which my summary correctly foregrounds.”