# noCV engineering task library Content version 5 Fictional engineering practice briefs. Starter repositories, fixtures, automated grading, and verified ownership are not included. Tests, patches, and runbooks are requested deliverables. They become Outcome Evidence only through a qualified Mission and immutable Evidence IDs. Independent adaptation must be observed under a declared verification policy and cite immutable Evidence IDs. Completing a planning ticket establishes no Ownership Evidence. ## CLIVE — A live incident board with recoverable updates Fictional internal status team Harbor updates operational incident cards. Build a local event log and SSE adapter; incidents and service names are invented. **Field:** Real-time systems. **Suggested stack:** TypeScript, Server-sent events, PostgreSQL adapter, React. **Engineer value:** Practice event projection, replay and freshness communication. **Company value:** Inspect whether dashboards remain trustworthy through network interruptions. **Delivery agreement:** Use local fixtures; this board is not an emergency-response system. ### Setup prerequisites - Create synthetic incident revisions and a local append-only event stub. - Provide controllable disconnect, replay and retention fixtures. ### Specify live events Define event identity and projection. #### CLIVE-101 — Give live incident events stable opaque identifiers **Task · Medium priority · Foundational** noCV practice brief v5 · CLIVE-101 · A live incident board with recoverable updates Fictional engineering practice briefs. Starter repositories, fixtures, automated grading, and verified ownership are not included. Phase: Specify live events. Depends on: No preceding ticket. Difficulty: Foundational. Estimated focused work: 75 minutes; setup and prerequisite tickets are additional. Estimated field mix: Real-time systems 60% · Data engineering 40%. Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence. Reconnecting clients cannot distinguish replay from new events because IDs change on delivery. Persist event identity. Acceptance criteria - Replay preserves IDs - Distinct events have unique IDs - IDs contain no incident text Implementation constraints - Delivery attempts must not mint new event IDs. Verification - Replay one event twice - Append two equal payloads as distinct events Deliverables - Event identity contract Rollout and recovery: Disable replay until stable IDs exist. Project prerequisites: Create synthetic incident revisions and a local append-only event stub. Provide controllable disconnect, replay and retention fixtures. Engineer value: Practice event projection, replay and freshness communication. Company value: Inspect whether dashboards remain trustworthy through network interruptions. AI tools are welcome during implementation. Record assumptions, review the result, and verify its behavior. Planning status does not create Outcome Evidence or Ownership Evidence. #### CLIVE-102 — Render incident status text independently of severity color **Bug · Medium priority · Foundational** noCV practice brief v5 · CLIVE-102 · A live incident board with recoverable updates Fictional engineering practice briefs. Starter repositories, fixtures, automated grading, and verified ownership are not included. Phase: Specify live events. Depends on: No preceding ticket. Difficulty: Foundational. Estimated focused work: 60 minutes; setup and prerequisite tickets are additional. Estimated field mix: Accessibility 70% · Frontend 30%. Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence. Color-only status blocks hide the distinction between investigating and monitoring. Add visible status labels. Acceptance criteria - Every status has text - Unknown status renders explicit fallback - Color is optional reinforcement Implementation constraints - Do not infer severity from color tokens. Verification - Render all fixture statuses - Render unsupported status Deliverables - Status presenter and cases Rollout and recovery: Use text-only presentation if color mapping is wrong. Project prerequisites: Create synthetic incident revisions and a local append-only event stub. Provide controllable disconnect, replay and retention fixtures. Engineer value: Practice event projection, replay and freshness communication. Company value: Inspect whether dashboards remain trustworthy through network interruptions. AI tools are welcome during implementation. Record assumptions, review the result, and verify its behavior. Planning status does not create Outcome Evidence or Ownership Evidence. #### CLIVE-103 — Apply live incident updates only to newer revisions **Bug · High priority · Intermediate** noCV practice brief v5 · CLIVE-103 · A live incident board with recoverable updates Fictional engineering practice briefs. Starter repositories, fixtures, automated grading, and verified ownership are not included. Phase: Specify live events. Depends on: CLIVE-101, CLIVE-102. Difficulty: Intermediate. Estimated focused work: 120 minutes; setup and prerequisite tickets are additional. Estimated field mix: Real-time systems 60% · Distributed systems 40%. Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence. A delayed update reopens a resolved incident. Compare revisions before changing the projected card. Acceptance criteria - Newer revisions apply - Equal replay is harmless - Older revisions cannot overwrite Implementation constraints - Revision scope is per incident. Verification - Apply revisions in order - Deliver earlier revision after resolution Deliverables - Revision projector and ordering cases Rollout and recovery: Refresh full cards if ordering cannot be established. Project prerequisites: Create synthetic incident revisions and a local append-only event stub. Provide controllable disconnect, replay and retention fixtures. Engineer value: Practice event projection, replay and freshness communication. Company value: Inspect whether dashboards remain trustworthy through network interruptions. AI tools are welcome during implementation. Record assumptions, review the result, and verify its behavior. Planning status does not create Outcome Evidence or Ownership Evidence. ### Recover transport gaps Make replay and mutation coherent. #### CLIVE-104 — Resume incident streams from the last applied event **Story · High priority · Advanced** noCV practice brief v5 · CLIVE-104 · A live incident board with recoverable updates Fictional engineering practice briefs. Starter repositories, fixtures, automated grading, and verified ownership are not included. Phase: Recover transport gaps. Depends on: CLIVE-103. Difficulty: Advanced. Estimated focused work: 180 minutes; setup and prerequisite tickets are additional. Estimated field mix: Real-time systems 60% · Networking 20% · Distributed systems 20%. Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence. A reconnect misses changes made during disconnection. Send the last applied event ID and replay retained updates. Acceptance criteria - Resume begins after acknowledged ID - Replay preserves event order - Cursor advances after successful projection Implementation constraints - Received is not equivalent to applied. Verification - Reconnect after two missed events - Fail projection before cursor advancement Deliverables - Resume coordinator and replay cases Rollout and recovery: Force snapshot reload instead of uncertain replay. Project prerequisites: Create synthetic incident revisions and a local append-only event stub. Provide controllable disconnect, replay and retention fixtures. Engineer value: Practice event projection, replay and freshness communication. Company value: Inspect whether dashboards remain trustworthy through network interruptions. AI tools are welcome during implementation. Record assumptions, review the result, and verify its behavior. Planning status does not create Outcome Evidence or Ownership Evidence. #### CLIVE-105 — Return a reset contract when incident replay history expired **Task · High priority · Intermediate** noCV practice brief v5 · CLIVE-105 · A live incident board with recoverable updates Fictional engineering practice briefs. Starter repositories, fixtures, automated grading, and verified ownership are not included. Phase: Recover transport gaps. Depends on: CLIVE-104. Difficulty: Intermediate. Estimated focused work: 135 minutes; setup and prerequisite tickets are additional. Estimated field mix: API design 50% · Real-time systems 30% · Storage systems 20%. Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence. Old clients request a cursor outside retention and appear current with missing changes. Make replay expiry explicit. Acceptance criteria - Expired cursor requests fresh snapshot - Client clears old cursor - Reset has an observable reason Implementation constraints - Do not silently start at the newest event. Verification - Resume retained cursor - Resume expired cursor Deliverables - Replay reset contract Rollout and recovery: Require full reload if reset handling fails. Project prerequisites: Create synthetic incident revisions and a local append-only event stub. Provide controllable disconnect, replay and retention fixtures. Engineer value: Practice event projection, replay and freshness communication. Company value: Inspect whether dashboards remain trustworthy through network interruptions. AI tools are welcome during implementation. Record assumptions, review the result, and verify its behavior. Planning status does not create Outcome Evidence or Ownership Evidence. #### CLIVE-106 — Join incident snapshots and streams at one watermark **Bug · High priority · Expert** noCV practice brief v5 · CLIVE-106 · A live incident board with recoverable updates Fictional engineering practice briefs. Starter repositories, fixtures, automated grading, and verified ownership are not included. Phase: Recover transport gaps. Depends on: CLIVE-104, CLIVE-105. Difficulty: Expert. Estimated focused work: 240 minutes; setup and prerequisite tickets are additional. Estimated field mix: Distributed systems 50% · Real-time systems 30% · Database engineering 20%. Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence. An update between snapshot fetch and stream connect disappears. Establish a snapshot watermark for replay. Acceptance criteria - Snapshot declares its watermark - Stream replays later events - Boundary duplicates remain harmless Implementation constraints - Define transaction or adapter ordering explicitly. Verification - Update before snapshot - Update between snapshot and subscription Deliverables - Snapshot-stream handoff and race cases Rollout and recovery: Use periodic full snapshots while handoff is repaired. Project prerequisites: Create synthetic incident revisions and a local append-only event stub. Provide controllable disconnect, replay and retention fixtures. Engineer value: Practice event projection, replay and freshness communication. Company value: Inspect whether dashboards remain trustworthy through network interruptions. AI tools are welcome during implementation. Record assumptions, review the result, and verify its behavior. Planning status does not create Outcome Evidence or Ownership Evidence. #### CLIVE-107 — Reconcile local incident edits with streamed acknowledgements **Story · Medium priority · Advanced** noCV practice brief v5 · CLIVE-107 · A live incident board with recoverable updates Fictional engineering practice briefs. Starter repositories, fixtures, automated grading, and verified ownership are not included. Phase: Recover transport gaps. Depends on: CLIVE-103, CLIVE-106. Difficulty: Advanced. Estimated focused work: 180 minutes; setup and prerequisite tickets are additional. Estimated field mix: Frontend 60% · Real-time systems 40%. Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence. Saving an incident and receiving its stream event produces duplicate activity rows. Correlate the committed operation. Acceptance criteria - One committed activity row appears - Rejected edits remain actionable - Unrelated remote events still apply Implementation constraints - Do not suppress all events while saving. Verification - Save and receive acknowledgement - Reject save while another user updates Deliverables - Mutation-stream reconciliation Rollout and recovery: Remove optimistic activity until correlation is correct. Project prerequisites: Create synthetic incident revisions and a local append-only event stub. Provide controllable disconnect, replay and retention fixtures. Engineer value: Practice event projection, replay and freshness communication. Company value: Inspect whether dashboards remain trustworthy through network interruptions. AI tools are welcome during implementation. Record assumptions, review the result, and verify its behavior. Planning status does not create Outcome Evidence or Ownership Evidence. ### Operate bounded streams Handle slow clients and explain freshness. #### CLIVE-108 — Bound each incident subscriber buffer **Task · Medium priority · Advanced** noCV practice brief v5 · CLIVE-108 · A live incident board with recoverable updates Fictional engineering practice briefs. Starter repositories, fixtures, automated grading, and verified ownership are not included. Phase: Operate bounded streams. Depends on: CLIVE-106. Difficulty: Advanced. Estimated focused work: 180 minutes; setup and prerequisite tickets are additional. Estimated field mix: Performance engineering 50% · Real-time systems 30% · Site reliability 20%. Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence. A slow status screen accumulates unbounded events. Cap its queue and require reset when it cannot keep up. Acceptance criteria - Queue respects configured bound - Overflow terminates with reset guidance - Other subscribers remain independent Implementation constraints - Never silently discard ordered events. Verification - Stream to healthy client - Stall client beyond queue capacity Deliverables - Subscriber backpressure policy Rollout and recovery: Disconnect slow subscribers and require fresh snapshots. Project prerequisites: Create synthetic incident revisions and a local append-only event stub. Provide controllable disconnect, replay and retention fixtures. Engineer value: Practice event projection, replay and freshness communication. Company value: Inspect whether dashboards remain trustworthy through network interruptions. AI tools are welcome during implementation. Record assumptions, review the result, and verify its behavior. Planning status does not create Outcome Evidence or Ownership Evidence. #### CLIVE-109 — Show incident-board freshness independently from incident status **Story · Medium priority · Intermediate** noCV practice brief v5 · CLIVE-109 · A live incident board with recoverable updates Fictional engineering practice briefs. Starter repositories, fixtures, automated grading, and verified ownership are not included. Phase: Operate bounded streams. Depends on: CLIVE-105, CLIVE-108. Difficulty: Intermediate. Estimated focused work: 105 minutes; setup and prerequisite tickets are additional. Estimated field mix: Frontend 60% · Real-time systems 40%. Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence. A disconnected screen says All systems normal because incident cards retain their last values. Add transport freshness. Acceptance criteria - Last applied time is visible - Disconnect shows stale state - Reconnect clears stale only after catch-up Implementation constraints - Use synthetic clock values in tests. Verification - Disconnect resolved board - Reconnect with missed open incident Deliverables - Freshness banner and recovery cases Rollout and recovery: Hide aggregate healthy claim while freshness is uncertain. Project prerequisites: Create synthetic incident revisions and a local append-only event stub. Provide controllable disconnect, replay and retention fixtures. Engineer value: Practice event projection, replay and freshness communication. Company value: Inspect whether dashboards remain trustworthy through network interruptions. AI tools are welcome during implementation. Record assumptions, review the result, and verify its behavior. Planning status does not create Outcome Evidence or Ownership Evidence. #### CLIVE-110 — Record incident-stream recovery reasons without payload logging **Chore · Low priority · Intermediate** noCV practice brief v5 · CLIVE-110 · A live incident board with recoverable updates Fictional engineering practice briefs. Starter repositories, fixtures, automated grading, and verified ownership are not included. Phase: Operate bounded streams. Depends on: CLIVE-109. Difficulty: Intermediate. Estimated focused work: 90 minutes; setup and prerequisite tickets are additional. Estimated field mix: Privacy engineering 60% · Real-time systems 20% · Site reliability 20%. Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence. Investigating replay failures currently logs full incident descriptions. Add an allowlisted recovery event schema. Acceptance criteria - Includes reset reason and cursor category - Omits descriptions and author names - Malformed IDs are bounded Implementation constraints - Correlation identifiers cannot carry user text. Verification - Capture successful resume - Reject secret-like malformed cursor Deliverables - Recovery diagnostics and exclusion checks Rollout and recovery: Disable stream logging if payload fields appear. Project prerequisites: Create synthetic incident revisions and a local append-only event stub. Provide controllable disconnect, replay and retention fixtures. Engineer value: Practice event projection, replay and freshness communication. Company value: Inspect whether dashboards remain trustworthy through network interruptions. AI tools are welcome during implementation. Record assumptions, review the result, and verify its behavior. Planning status does not create Outcome Evidence or Ownership Evidence.