Spot Capacity Orchestrator  ·  View 31 of 32  ·  7 · Assurance

Spend Authority

Who may turn a capacity shortage into a bill, how their approval is proved, and how every step is recorded outside the telemetry pipeline.

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Fallback arbiter Spend ledger Incident platform Budget owner OpenBao Nova Audit log 1. deadline risk: needs €2,400 more 2. reserve against 24 h cap 3. cap exhausted 4. approval request · expires 15 min 5. page with priced options 6. approve €2,400 · OIDC + WebAuthn 7. approver named in contract? 8. reserve with approver id 9. fallback.approved by owner 10. provider credential 11. 1 h · sco projects only 12. launch guaranteed · tag sco:fallback 13. capacity.launch · policy + approver 14. no answer at 15 min: shortfall, no spend Spend Authority — Who May Turn a Shortage Into a Bill Restoring the floor never reaches step 4: it is pre-authorised by the tier and drawn from committed capacity already paid for. v 1.0 · owner Compute Platform Architecture · date 2026-09

Decisions

  • Moving work from reclaimable to guaranteed capacity is treated as spending money, because it is. The approver must be named in the contract, sign in with a phishing-resistant factor, and approve a priced option rather than a vague request.
  • Every capacity action records the identity that caused it: an operator, a policy, or a policy acting under a named approval. The record goes to the audit log service through an outbox, independent of Kafka and ClickHouse.

Separation of authority

  • Routine contract edits need the platform team's review. Floors, spend caps and fallback policy need a governance signature as well. Operators of the orchestrator cannot approve their own fallback spend.

Risk

  • A budget owner who never answers at night turns every broad shortage into a recorded shortfall. That is the chosen failure; the review after each one decides whether the cap was simply too low.