{ "policy": { "version": 5, "patterns": { "version": 1, "method": "CURATED_PRACTICE_TOPIC", "notice": "Pattern topics identify design choices to practice. Read the ticket's acceptance criteria and justify the simplest suitable approach. Tags are not capability or ownership evidence; an untagged ticket has no curated pattern topic assigned." }, "fieldMix": { "version": 1, "method": "CURATED_ESTIMATE", "notice": "Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence." }, "contentStatus": "PRACTICE_BRIEF", "assessmentStatus": "NOT_QUALIFIED", "evidenceUse": "NONE", "aiPolicy": "AI tools are welcome during implementation. Record assumptions, review the result, and verify its behavior.", "notice": "Fictional engineering practice briefs. Starter repositories, fixtures, automated grading, and verified ownership are not included.", "outcomeEvidence": "Tests, patches, and runbooks are requested deliverables. They become Outcome Evidence only through a qualified Mission and immutable Evidence IDs.", "ownershipEvidence": "Independent adaptation must be observed under a declared verification policy and cite immutable Evidence IDs. Completing a planning ticket establishes no Ownership Evidence." }, "patternTopics": [ { "id": "factory-method", "label": "Factory Method", "group": "Creational" }, { "id": "abstract-factory", "label": "Abstract Factory", "group": "Creational" }, { "id": "builder", "label": "Builder", "group": "Creational" }, { "id": "prototype", "label": "Prototype", "group": "Creational" }, { "id": "singleton", "label": "Singleton", "group": "Creational" }, { "id": "adapter", "label": "Adapter", "group": "Structural" }, { "id": "bridge", "label": "Bridge", "group": "Structural" }, { "id": "composite", "label": "Composite", "group": "Structural" }, { "id": "decorator", "label": "Decorator", "group": "Structural" }, { "id": "facade", "label": "Facade", "group": "Structural" }, { "id": "flyweight", "label": "Flyweight", "group": "Structural" }, { "id": "proxy", "label": "Proxy", "group": "Structural" }, { "id": "chain-of-responsibility", "label": "Chain of Responsibility", "group": "Behavioral" }, { "id": "command", "label": "Command", "group": "Behavioral" }, { "id": "interpreter", "label": "Interpreter", "group": "Behavioral" }, { "id": "iterator", "label": "Iterator", "group": "Behavioral" }, { "id": "mediator", "label": "Mediator", "group": "Behavioral" }, { "id": "memento", "label": "Memento", "group": "Behavioral" }, { "id": "observer", "label": "Observer", "group": "Behavioral" }, { "id": "state", "label": "State", "group": "Behavioral" }, { "id": "strategy", "label": "Strategy", "group": "Behavioral" }, { "id": "template-method", "label": "Template Method", "group": "Behavioral" }, { "id": "visitor", "label": "Visitor", "group": "Behavioral" }, { "id": "ports-and-adapters", "label": "Ports and Adapters", "group": "Architectural" }, { "id": "cqrs", "label": "CQRS", "group": "Architectural" }, { "id": "strangler-fig", "label": "Strangler Fig", "group": "Architectural" }, { "id": "saga", "label": "Saga", "group": "Distributed and reliability" }, { "id": "transactional-outbox", "label": "Transactional Outbox", "group": "Distributed and reliability" }, { "id": "circuit-breaker", "label": "Circuit Breaker", "group": "Distributed and reliability" }, { "id": "bulkhead", "label": "Bulkhead", "group": "Distributed and reliability" } ], "projects": [ { "id": "3ca4922d-a6d3-4d7b-880d-85ebffbd7f85", "key": "ABATCH", "title": "Aggregate parallel risk checks without losing partial outcomes", "field": "Distributed systems", "summary": "Coordinate independent document checks into a bounded, reproducible aggregate result.", "context": "A fictional vendor portal runs format, policy and duplicate checks in parallel. A slow checker blocks completion, while duplicate callbacks can produce contradictory final summaries.", "stack": [ "TypeScript", "PostgreSQL", "Provider interfaces" ], "prerequisites": [ "Create synthetic document identities and three fake check providers.", "No real risk scoring, hiring decisions or candidate execution is included." ], "developerValue": "Practice fan-out/fan-in, deadline policies and immutable aggregation.", "companyValue": "Review trustworthy partial-result handling and controllable parallel work.", "delivery": "Ten scoped tickets across three phases. Build a synthetic local service or select a ticket after recreating its prerequisites; estimates exclude setup.", "phases": [ { "id": "contract", "title": "Define independent check facts", "goal": "Specify input identity, required checks and result states." }, { "id": "aggregate", "title": "Coordinate parallel outcomes", "goal": "Dispatch, deduplicate and finalize with explicit deadlines." }, { "id": "recover", "title": "Recover incomplete runs", "goal": "Replay work and explain aggregate provenance." } ], "tickets": [ { "id": "f59d8645-6321-475b-8dc1-1425d0c1e432", "key": "ABATCH-101", "title": "Freeze the required check set when a document review run starts", "type": "TASK", "priority": "MEDIUM", "difficulty": "FOUNDATIONAL", "estimateMinutes": 90, "phaseId": "contract", "dependsOn": [], "scenario": "A configuration change adds a checker while a run is in progress, so the completion predicate changes halfway through.", "acceptanceCriteria": [ "Record exact checker identities and versions per run.", "Bind the set to immutable document input identity.", "New configuration affects only new runs." ], "implementationNotes": [ "Use three deterministic fake checks with no capability scoring." ], "verification": [ "Start runs before and after a check-set change.", "Finish the older run using its original required set." ], "deliverables": [ "Review-run manifest" ], "rollout": "Publish frozen manifests before parallel dispatch; retain prior checker versions for replay.", "skills": [ "Immutability", "Workflow contracts" ], "fieldMix": [ { "field": "Distributed systems", "percentage": 60 }, { "field": "Backend", "percentage": 40 } ], "patterns": [] }, { "id": "a4876a91-5370-4caf-971c-8a022482ef24", "key": "ABATCH-102", "title": "Define pass, fail, unavailable and not-applicable check outcomes", "type": "TASK", "priority": "MEDIUM", "difficulty": "INTERMEDIATE", "estimateMinutes": 150, "phaseId": "contract", "dependsOn": [ "ABATCH-101" ], "scenario": "A timed-out policy checker returns an empty findings list, which the aggregator interprets as passed.", "acceptanceCriteria": [ "Use explicit outcome states with bounded structured details.", "Require justification for not-applicable under the declared contract.", "Keep unavailable distinct from an empty successful result." ], "implementationNotes": [ "Reject unsupported fields and prohibit demographic or personality inferences." ], "verification": [ "Accept a valid empty successful check.", "Timeout a checker and retain unavailable rather than pass." ], "deliverables": [ "Check-result schema and semantic cases" ], "rollout": "Deploy result validation before aggregate updates; quarantine incompatible provider output.", "skills": [ "Structured validation", "Uncertainty" ], "fieldMix": [ { "field": "Distributed systems", "percentage": 60 }, { "field": "API design", "percentage": 40 } ], "patterns": [] }, { "id": "857f056b-1cea-4504-9955-31fa5d39657b", "key": "ABATCH-103", "title": "Bound parallel check fan-out per organization and run", "type": "TASK", "priority": "MEDIUM", "difficulty": "FOUNDATIONAL", "estimateMinutes": 90, "phaseId": "contract", "dependsOn": [ "ABATCH-101", "ABATCH-102" ], "scenario": "One tenant submits many documents and the coordinator starts every check immediately, exhausting provider slots.", "acceptanceCriteria": [ "Set explicit per-run and per-tenant in-flight limits.", "Persist queued attempts instead of dropping them.", "Return admission status separate from check completion." ], "implementationNotes": [ "Use documented synthetic limits and a fake provider counter." ], "verification": [ "Dispatch a permitted number of synthetic checks.", "Exceed the tenant limit and verify excess work remains queued without provider calls." ], "deliverables": [ "Fan-out admission guard" ], "rollout": "Canary conservative limits; pause admission when provider capacity is unknown.", "skills": [ "Concurrency budgets", "Admission control" ], "fieldMix": [ { "field": "Distributed systems", "percentage": 50 }, { "field": "Performance engineering", "percentage": 30 }, { "field": "Platform engineering", "percentage": 20 } ], "patterns": [] }, { "id": "097f7552-8b65-4d3e-9704-273063d6eb46", "key": "ABATCH-104", "title": "Dispatch each check through a durable deterministic attempt identity", "type": "STORY", "priority": "MEDIUM", "difficulty": "ADVANCED", "estimateMinutes": 240, "phaseId": "aggregate", "dependsOn": [ "ABATCH-101", "ABATCH-103" ], "scenario": "The coordinator crashes after dispatching one checker and cannot tell which of the three still needs to start.", "acceptanceCriteria": [ "Persist check-attempt identity and outbox dispatch per required checker.", "Keep dispatch retries bound to the same input and checker version.", "Reject contradictory reuse of an attempt identity." ], "implementationNotes": [ "Call providers outside the database transaction." ], "verification": [ "Crash after one dispatched check and resume remaining work.", "Replay an outbox fact and keep one logical provider attempt." ], "deliverables": [ "Check dispatch transaction and crash probe" ], "rollout": "Prototype with fake providers; stop new runs if attempt identity cannot be persisted.", "skills": [ "Outbox", "Idempotency" ], "fieldMix": [ { "field": "Distributed systems", "percentage": 60 }, { "field": "Database engineering", "percentage": 40 } ], "patterns": [] }, { "id": "62416955-f6e2-4604-95e7-cd775dee0e35", "key": "ABATCH-105", "title": "Deduplicate callbacks without accepting contradictory check results", "type": "TASK", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 210, "phaseId": "aggregate", "dependsOn": [ "ABATCH-102", "ABATCH-104" ], "scenario": "A provider retries its callback and later sends a changed result for the same attempt ID.", "acceptanceCriteria": [ "Identical callback retries resolve one recorded result.", "Different terminal content for the same attempt creates a conflict.", "Validate run, input and checker identities before recording." ], "implementationNotes": [ "Use canonical result hashes and authenticated fixture callbacks." ], "verification": [ "Deliver the same terminal callback twice.", "Alter a terminal result or input hash and keep the accepted result plus a visible conflict." ], "deliverables": [ "Callback ingestion guard" ], "rollout": "Canary callback handling; quarantine contradictory provider output without rewriting terminal facts.", "skills": [ "Deduplication", "Integrity" ], "fieldMix": [ { "field": "Distributed systems", "percentage": 60 }, { "field": "Integrations", "percentage": 40 } ], "patterns": [] }, { "id": "3cc493da-b992-4048-b617-2c9aa3b66538", "key": "ABATCH-106", "title": "Finalize aggregates only from the frozen required check set", "type": "TASK", "priority": "HIGH", "difficulty": "EXPERT", "estimateMinutes": 300, "phaseId": "aggregate", "dependsOn": [ "ABATCH-101", "ABATCH-102", "ABATCH-105" ], "scenario": "An optional checker finishes quickly and accidentally satisfies a counter-based completion condition while a required checker is missing.", "acceptanceCriteria": [ "Evaluate completeness by exact required identities.", "Compute aggregate state from validated immutable check facts.", "Reject finalization when required results are missing or conflicting." ], "implementationNotes": [ "Define aggregate output as review status, never an opaque hire/reject score." ], "verification": [ "Finish all required checks and produce the expected status.", "Complete extra optional checks while omitting one required check and block completion." ], "deliverables": [ "Aggregate reducer and completeness tests" ], "rollout": "Enable guarded finalization before publishing results; retain pending state on missing authority.", "skills": [ "Aggregation", "Set invariants" ], "fieldMix": [ { "field": "Distributed systems", "percentage": 60 }, { "field": "Backend", "percentage": 40 } ], "patterns": [] }, { "id": "bc74ab32-c7a1-4bf4-ae2a-eef6c6c91bb1", "key": "ABATCH-107", "title": "Apply a run deadline without rewriting late check facts", "type": "STORY", "priority": "MEDIUM", "difficulty": "INTERMEDIATE", "estimateMinutes": 180, "phaseId": "aggregate", "dependsOn": [ "ABATCH-102", "ABATCH-106" ], "scenario": "A slow checker returns after the review deadline and overwrites a summary already shown to the user.", "acceptanceCriteria": [ "Define a deadline terminal state with explicit incomplete checks.", "Preserve late results as appended facts without mutating the frozen summary.", "Allow a new run or reviewed amendment under an explicit policy." ], "implementationNotes": [ "Use an injected clock and exact boundary cases." ], "verification": [ "Complete required checks before deadline.", "Return one check after deadline and retain the original summary plus late-result visibility." ], "deliverables": [ "Deadline finalization and late-result cases" ], "rollout": "Canary synthetic short deadlines; create new runs when a policy change requires reevaluation.", "skills": [ "Temporal workflows", "Append-only results" ], "fieldMix": [ { "field": "Distributed systems", "percentage": 60 }, { "field": "Backend", "percentage": 40 } ], "patterns": [] }, { "id": "d0fa630d-ba3f-430d-8f49-47d7310f2fca", "key": "ABATCH-108", "title": "Recover outstanding checks by querying provider attempt identity", "type": "TASK", "priority": "MEDIUM", "difficulty": "EXPERT", "estimateMinutes": 300, "phaseId": "recover", "dependsOn": [ "ABATCH-104", "ABATCH-105", "ABATCH-107" ], "scenario": "After a restart, several attempts are marked dispatched but have no callback; immediate resubmission may duplicate costly work.", "acceptanceCriteria": [ "Reconcile each unresolved attempt through its provider identity.", "Redispatch only under the adapter's declared idempotency contract.", "Keep unknown provider state visible and bounded." ], "implementationNotes": [ "Use fake providers that model lost callbacks and unavailable lookup." ], "verification": [ "Recover a completed check whose callback was lost.", "Make provider lookup unavailable and verify no unsupported success or duplicate attempt." ], "deliverables": [ "Outstanding-attempt reconciler" ], "rollout": "Start recovery with bounded batches; suspend affected adapters when identity guarantees fail.", "skills": [ "Reconciliation", "Distributed failure" ], "fieldMix": [ { "field": "Distributed systems", "percentage": 60 }, { "field": "Integrations", "percentage": 40 } ], "patterns": [] }, { "id": "3b6351c0-e4f7-4c2b-9259-9fdfc004e827", "key": "ABATCH-109", "title": "Produce a result provenance view that names missing and conflicting checks", "type": "STORY", "priority": "MEDIUM", "difficulty": "FOUNDATIONAL", "estimateMinutes": 90, "phaseId": "recover", "dependsOn": [ "ABATCH-105", "ABATCH-106", "ABATCH-107", "ABATCH-108" ], "scenario": "Users receive only a summary label and cannot inspect whether every required checker actually ran.", "acceptanceCriteria": [ "List frozen checker versions and input identity.", "Show outcome, unavailable and conflict states separately.", "Keep internal prompts, secrets and raw provider traces out of the view." ], "implementationNotes": [ "Use public practice facts only; this is not noCV assessment evidence." ], "verification": [ "Inspect a complete synthetic aggregate.", "Inspect a deadline result and clearly identify the missing checker." ], "deliverables": [ "Safe provenance projection" ], "rollout": "Publish read-only provenance with aggregate status; hide fields that fail schema review.", "skills": [ "Provenance", "Transparency" ], "fieldMix": [ { "field": "Distributed systems", "percentage": 40 }, { "field": "API design", "percentage": 30 }, { "field": "Privacy engineering", "percentage": 30 } ], "patterns": [] }, { "id": "f338a38a-afb2-4ec7-ae22-c806b4968617", "key": "ABATCH-110", "title": "Exercise the parallel-check coordinator under reordered failures", "type": "CHORE", "priority": "MEDIUM", "difficulty": "ADVANCED", "estimateMinutes": 240, "phaseId": "recover", "dependsOn": [ "ABATCH-105", "ABATCH-106", "ABATCH-107", "ABATCH-108", "ABATCH-109" ], "scenario": "Happy-path tests always complete checks in the same order and miss a race between deadline finalization and the last callback.", "acceptanceCriteria": [ "Run permutations of declared completion, timeout and conflict events.", "Assert one immutable summary and complete retained check history.", "Record any unsupported adapter guarantee as a failing readiness condition." ], "implementationNotes": [ "Use a deterministic event scheduler; no arbitrary sleeps." ], "verification": [ "Run all required checks in several completion orders with equal final semantics.", "Race final callback with deadline and verify the declared single outcome." ], "deliverables": [ "Deterministic coordinator fault harness" ], "rollout": "Require the harness before adapter changes; retain the prior coordinator version if invariants fail.", "skills": [ "Concurrency testing", "Fault injection" ], "fieldMix": [ { "field": "Quality engineering", "percentage": 50 }, { "field": "Distributed systems", "percentage": 50 } ], "patterns": [] } ] } ] }