Simon Willison: April 2026 Newsletter — Independent Analysis of Opus 4.7, GPT-5.5, and the State of AI Engineering

Simon Willison·low signal

Willison published his sponsors-only April 2026 newsletter covering Opus 4.7, GPT-5.5, and the broader state of AI engineering tools. As one of the most trusted independent voices in the AI developer space, his monthly synthesis typically surfaces under-discussed angles and practical implications that don't appear in mainstream coverage. The newsletter also covers developments in his datasette/LLM ecosystem.