Simon Willison — Week of 2026-06-06 to 2026-06-12#

Highlight of the Week#

The standout event this week was the release of Anthropic’s massive Claude Fable 5 model, which Simon immediately leveraged as a highly capable coding partner to essentially author complex new features across his open-source ecosystem. However, the most impactful takeaway was his deep dive into the model’s terrifyingly autonomous capabilities—such as independently writing CORS servers and injecting JavaScript just to debug a CSS glitch—which served as a stark reminder of why executing AI-generated code requires strict sandboxing.

Simon Willison — 2026-06-08#

Highlight#

Simon takes a cautious approach to Apple’s WWDC 2026 AI announcements, but notes that their screen-reading vision LLM strategy and new PyTorch integration for local models look highly promising for developers.

Posts#

Siri AI at WWDC 2026 · Source Reflecting on WWDC 2026, Simon adopts an “I’ll believe it when I see it” stance regarding Apple Intelligence, given the overpromises of the 2024 rollout. However, he points out that the latest Siri AI features appear technically viable, powered by a custom Gemini-derived model on Private Cloud Compute and vision LLMs that extract on-screen data without requiring third-party app updates. He is particularly interested in the new Core AI library and its coreai-torch Python package, which provides a straightforward bridge for developers to export PyTorch models into native programs optimized for Apple hardware.