Edge Cache and CDN Platform · View 04 of 29 · 2 · People and journeys
The trough, and the answer
- Validation rejects /account because its responses differ between two test users, and the declared key has no identity in it. The owner is annoyed for an afternoon. Without the check, the platform would have served one reader's account page to another, with no error anywhere.
- Canary hit ratio of 71% against a 96% target is usually an allow-list gap: a marketing parameter such as utm_source left in the key. The per-path hit ratio names the pattern, and explain shows the parameter.
Decisions it forces
- Nothing is cacheable until the owner says so. The first merge request caches the static assets only, which already takes most of the bytes.
- The explain tool runs the production key library, not a copy of its logic (ADR-02).
- Ring rollout halts itself on a hit-ratio regression, not only on errors, because a bad key usually shows up as a lower hit ratio before it shows up as an error.
Numbers
- Median onboarding target of two working days from first merge request to global, most of it the owner's own testing.
- Canary bake of 10 minutes on one PoP, then 20 minutes on one continent.
