GitHub rebuilt Copilot's runtime in Rust and shipped it as an SDK
Agents did most of the 430K-line port in 14.5 weeks; the same week, six Copilot models get a retirement date and ubuntu-latest jumps to 26.04.
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One engineer, an army of agents, one Rust runtime
GitHub ported ~430K lines of Copilot's TypeScript runtime to Rust in 14.5 weeks (May 12-Aug 21) - 832K lines of Rust plus 468K of unit tests across 128 merged PRs, with AI agents writing most of the code under a single supervising engineer. GitHub says the rebuilt runtime is now 'orders of magnitude' faster.
You can now embed the runtime in your own app
The Rust core ships as an in-process SDK for TypeScript, Python, Go, C#, Java, and Rust, all speaking one bidirectional JSON-RPC contract over language-native FFI. That means you can drop the Copilot agent runtime straight into your own tool instead of shelling out to a subprocess or a cloud round-trip.
Six Copilot models hit their retirement date
On October 19, Copilot drops Gemini 3.7 Flash, GPT-5.5, GPT-5.4, GPT-5.4 mini, GPT-5 mini, and Grok 4.5. Suggested swaps are Gemini 3.8 Flash, GPT-5.6 Sol, GPT-5.6 Luna, and Grok 4.6 - Business and Enterprise get them auto-enabled unless an admin opts out. If a workflow pins one of these, repoint it now.
ubuntu-latest becomes Ubuntu 26.04
Ubuntu 26.04 runners are GA on x64 and arm64, and the ubuntu-latest label starts migrating off 24.04 between October 19 and November 19. If your CI pins tool versions loosely, run a job on 26.04 now to catch breakage before the label flips under you.
AI Scan drops the CodeQL requirement
GitHub's code-scanning AI Scan now finds vulnerabilities without a CodeQL default setup, so you can switch on scanning for repos and languages CodeQL never covered. One less config step between you and a security baseline.
Elsewhere: an open-weight world model you can actually run
Zing-0.5 is a 5B real-time interactive world model - 832x480 at 24 fps for about $0.009 a stream-minute - with weights, inference code, and a serving stack released. Joint keyboard-plus-text control means you can build a playable, promptable environment this weekend.