Ticket
Login latency regression on EU homepage after deploy 2026-04-21. Acceptance < 220ms.
Substrate
Closes the loop
Login latency regression on EU homepage after deploy 2026-04-21. Acceptance < 220ms.
Decision: roll forward with edge fix, not rollback. Cost trade accepted, infra + product.
edge/cache.ts owns the surface. Pattern: stale-while-revalidate. Owners: @rin, @lev.
Issue #4012 same shape, fixed by widening the cache key in 2025-11. Avoid re-introducing the regression.
Substrate holds all of them and retrieves the right slice for the work in front of it.
None are nice-to-have. All are reached for by default.
The base loop reorganizes its roster for the problem in front of it: Curator, Planner, Executor, Evaluator.
Substrate
Click to release
FROM SUBJECTIVE TO DETERMINISTIC
Behavioral coverage. Did the change exercise the surfaces it was meant to the paths, the edge cases, the regressions worth catching?
Spec adherence. Does the output meet the solution definition the Planner authored? Judgments 'idiomatic,' 'meets the spec' made concrete.
Code quality. Idiomatic, legible, conventions-respecting against the customer's repo. The Harness reads it the way a senior reviewer would.
Reasoning-trace integrity. Is the Executor's chain of reasoning sound, or did it shortcut to an output that happens to pass shallow checks?
shape Substrate can pick up
id · scope · acceptanceconventions Substrate stays legible against
CODEOWNERS · ADRssegmentable + retrievable
speakers · decisionsretrieval-optimized
chunked · addressableOur AI engineers can ship your use cases to production.