Anthropic
Every AI Founder Weekly story on Anthropic, newest first. 11 stories since September 2026.
- Marc Lou says the Opus 5.5 gap over OpenAI keeps widening
One founder's side by side on a non coding task, and the complaint is hedging rather than accuracy.
- Opus 5.5 takes half of all T3 Code prompts
Two teams report the same swing toward Anthropic in the same week.
- Anthropic ships Claude Sonnet 5.5, 30% faster
The cheap tier just moved, but every number so far is Anthropic's own.
- Theo says a $200 Claude sub bought $9,000 of Opus a month
Three accounts drained to zero, and the metered value of what came out was roughly 45 times the sticker price.
- Opus 5.5 built a 277k-gate computer in one 30-hour run
One prompt, no supervision, and a machine you can actually run in the browser.
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- Codex user says his $200 plan now lasts two days
calle bought a $200 Claude plan out of frustration and says Opus 5.5 feels like five times the usage.
- Rauch says Anthropic fell from 69% to 40% of Vercel spend
Two months of gateway spend data shows developer dollars moving fast, and open models taking about half of the difference.
- Opus 5.5 cut Arvid Kahl's test suite to 6m27s
He says the model found an inactive cache setting in his PHP runtime and refactored several thousand serial tests to run in parallel.
- Opus 5.5 ported HAProxy to Rust in 9.5 hours, Anthropic says
Anthropic's own head to head has the new model finishing a real port faster and cheaper, which is exactly why it needs an outside run.
- Anthropic merges Claude Cowork and chat into one Claude
Hand over a task, close the laptop, and Claude keeps going, with Docs, Slides and Design now inside every conversation.
- Founders split three ways over Dario Amodei's AI letter
Capture, liability and open access are the three camps forming in the replies, and none of them agree on what happens to open weights.
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