Agent Substrate
High-density runtime that multiplexes many stateful agents onto few Kubernetes workers.
Agent Substrate is an Apache-2.0 runtime that suspends idle agent 'actors' and resumes them in under a second, letting it multiplex roughly 250 stateful agents onto 8 Kubernetes pods; Google states it achieves about 10x higher density than standard container runtimes.
Caveat: Google open-sourced it but states it is not an officially supported Google product and was in early development (not production-ready) at verification time.
Key facts
| Category | Execution Sandbox |
|---|---|
| License | Apache-2.0 |
| Language | Go |
| Self-hosted | Yes |
| GitHub stars | 4,248 (2026-10-04) |
| Last push | 2026-10-03 |
| Last verified | 2026-10-04 |
| Repository | https://github.com/agent-substrate/substrate |
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