Anthropic $45B Nscale deal, OpenAI on GCP — AI News Oct 21

- Anthropic is reportedly negotiating a second ~$45B Nscale compute deal (460MW, Nvidia Vera Rubin chips) days after Microsoft walked away from the same West Virginia site — while Anthropic has signed $517B in compute in 11 months and awaits its IPO. - OpenAI's models and Codex tools are now available through Google Cloud's Model Garden and Marketplace, ending the Microsoft-only distribution era. - Meta pauses Muse after private AI chats leak online, a day after Fortune reported a pre-release hack exposed user addresses. - NVIDIA's new Nemotron 3.5 Embed, Rerank and Parse open-weight models bring self-hostable RAG infrastructure with training recipes. - Plus: WorkOS on agent-to-agent SSO, Gemini for government services, a Claude Code sandbox warning, and why open models still trail on accounting consistency. Follow AI Engineering Briefing and leave a rating — it's how new listeners find the show.