This week's chart tracks lines of code merged per engineer, per quarter, at Anthropic. From 2021 through to early 2025, the bars sit flat, barely moving. Then they go near-vertical. By Q2 2026, Anthropic's engineers are merging eight times as much code per quarter as they did before 2025. More than 80% of it was written by Claude.
In May, when we covered Jack Clark's "perspiration principle": his argument that the routine, iterative work of AI research was becoming tractable enough for machines to take on. Clark, who co-authored Anthropic's paper published this week, put the probability of recursive self-improvement at 60% by 2028. Looking at that chart, we wonder whether even that estimate is now too conservative.
Anthropic is simultaneously publishing this data and calling for a verifiable global pause mechanism, a kind of arms-control treaty for frontier AI development. The tension in that position is the point. They can see, from their own internal numbers, exactly how fast this is moving. Detractors have countered that this is more pre-IPO theatre. Only time will tell.