Agent Substrate
The sandbox runtime under AX. It maps many actors (usually agents) onto a smaller pool
of ready workers, since agents are idle most of the time. It handles create, destroy, suspend and
resume, assigns actors to workers in real time, and routes traffic to them. It is built on
Kubernetes pods and pod autoscaling, and supports gVisor and microVM sandboxes. Apache 2.0;
repository created 2026-05-13 under the agent-substrate organization (google-ax-infoq).
Claims (its own README, not measured by anyone else)
- Sub-500 ms resume; over 500 suspend/resume activations per second.
- 10x higher density than standard container runtimes.
- A demo multiplexes about 250 stateful actors onto 8 pods ("30x+ oversubscription"), keeping memory and filesystem state across suspend.
Status
The README says it "is not an officially supported Google product" and is outside Google's open-source vulnerability reward programme. InfoQ presents the whole stack as Google's; the repository is more careful.
Related
google-ax · compute-sandbox · modal-1m-sandboxes · google-ax-infoq