{ "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": "992e2b16-9300-45f2-bc00-b0b78f58aaa9", "key": "CJOUR", "title": "A power-loss-tolerant edge event journal", "field": "Embedded and edge", "summary": "Persist synthetic gateway events in a bounded software flash emulator.", "context": "Fictional edge display gateway stores noncritical synthetic readings while disconnected. Implement a byte-array flash emulator with explicit erase/write behavior and injected power cuts; no physical storage device is required.", "stack": [ "TypeScript", "Flash-storage emulator", "Vitest" ], "prerequisites": [ "Specify emulator page size write rules and erase behavior.", "Generate synthetic records and deterministic power-cut schedules." ], "developerValue": "Practice torn writes, wear-aware batching and acknowledged durability.", "companyValue": "Inspect whether offline device records remain recoverable within stated constraints.", "delivery": "Emulator guarantees are explicit; real flash endurance and device qualification remain separate.", "phases": [ { "id": "records", "title": "Define durable records", "goal": "Encode and validate journal entries." }, { "id": "power", "title": "Recover interrupted writes", "goal": "Handle commits and page boundaries." }, { "id": "capacity", "title": "Manage finite storage", "goal": "Reclaim acknowledged records safely." } ], "tickets": [ { "id": "62abe268-a5d9-4eec-a600-cfe72915d90e", "key": "CJOUR-101", "title": "Model edge-journal flash writes with explicit emulator constraints", "type": "TASK", "priority": "MEDIUM", "difficulty": "FOUNDATIONAL", "estimateMinutes": 90, "phaseId": "records", "dependsOn": [], "scenario": "The byte-array stub permits writes that real flash-like storage would reject. Declare and enforce the chosen emulator model.", "acceptanceCriteria": [ "Page boundaries are explicit", "Forbidden bit transitions fail", "Erase resets one selected page" ], "implementationNotes": [ "This models selected behavior and does not certify real hardware." ], "verification": [ "Write allowed transition", "Attempt forbidden transition without erase" ], "deliverables": [ "Flash emulator contract and cases" ], "rollout": "Stop journal writes when adapter behavior violates the declared model.", "skills": [ "Emulation", "Storage" ], "fieldMix": [ { "field": "Embedded and edge", "percentage": 60 }, { "field": "Storage systems", "percentage": 40 } ], "patterns": [] }, { "id": "2c45d8f3-059d-459f-b5f5-a8ece8f02786", "key": "CJOUR-102", "title": "Encode edge-journal records with bounded length and checksum", "type": "TASK", "priority": "HIGH", "difficulty": "FOUNDATIONAL", "estimateMinutes": 90, "phaseId": "records", "dependsOn": [ "CJOUR-101" ], "scenario": "Truncated synthetic records are indistinguishable from valid short payloads. Add explicit length and integrity fields.", "acceptanceCriteria": [ "Payload bytes round-trip", "Length is bounded", "Checksum mismatch rejects record" ], "implementationNotes": [ "Checksum is corruption detection, not authentication." ], "verification": [ "Encode valid record", "Flip one stored byte" ], "deliverables": [ "Record codec and corruption cases" ], "rollout": "Keep affected pages read-only for inspection.", "skills": [ "Binary formats", "Integrity" ], "fieldMix": [ { "field": "Embedded and edge", "percentage": 50 }, { "field": "Storage systems", "percentage": 50 } ], "patterns": [] }, { "id": "4f788f4f-fe84-4a29-a5b9-04cd9f8a072f", "key": "CJOUR-103", "title": "Assign edge-journal event identities independently from delivery attempts", "type": "BUG", "priority": "MEDIUM", "difficulty": "INTERMEDIATE", "estimateMinutes": 105, "phaseId": "records", "dependsOn": [ "CJOUR-102" ], "scenario": "Retried uploads mint new event IDs and duplicate accepted readings. Persist identity with the original record.", "acceptanceCriteria": [ "Retry preserves identity", "New records get distinct identity", "Restart retains stored identity" ], "implementationNotes": [ "IDs must not encode raw reading values." ], "verification": [ "Retry same record", "Restart and compare identities" ], "deliverables": [ "Event identity contract and cases" ], "rollout": "Pause replay if stored identity cannot be recovered.", "skills": [ "Idempotency", "Identity" ], "fieldMix": [ { "field": "Embedded and edge", "percentage": 50 }, { "field": "Distributed systems", "percentage": 30 }, { "field": "Storage systems", "percentage": 20 } ], "patterns": [] }, { "id": "30ca4175-6d9e-4ee7-8231-756f56fcff5b", "key": "CJOUR-104", "title": "Commit edge-journal records only after their marker is durable", "type": "TASK", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 180, "phaseId": "power", "dependsOn": [ "CJOUR-102", "CJOUR-103" ], "scenario": "A record appears readable before its body finishes writing. Introduce a commit-marker protocol compatible with the emulator.", "acceptanceCriteria": [ "Uncommitted bodies stay invisible", "Acknowledgement follows durable marker", "Invalid marker cannot authorize partial body" ], "implementationNotes": [ "Specify write and flush ordering explicitly." ], "verification": [ "Write committed fixture", "Cut power before marker" ], "deliverables": [ "Commit protocol and cut-point tests" ], "rollout": "Disable acknowledgement if the durability barrier fails.", "skills": [ "Durability", "Atomicity" ], "fieldMix": [ { "field": "Storage systems", "percentage": 60 }, { "field": "Embedded and edge", "percentage": 40 } ], "patterns": [] }, { "id": "6d2fd934-9c5a-4143-ae27-d07ab71d41bc", "key": "CJOUR-105", "title": "Recover edge-journal scanning after a torn final record", "type": "BUG", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 180, "phaseId": "power", "dependsOn": [ "CJOUR-104" ], "scenario": "Startup stops at partial data and loses earlier committed events. Scan the valid committed prefix conservatively.", "acceptanceCriteria": [ "Earlier committed records survive", "Incomplete tail is ignored with reason", "Middle corruption is not silently skipped" ], "implementationNotes": [ "Preserve damaged bytes for explicit local diagnosis." ], "verification": [ "Cut final body write", "Corrupt an earlier committed record" ], "deliverables": [ "Recovery scanner and fault cases" ], "rollout": "Open journal read-only when corruption is not a tail interruption.", "skills": [ "Recovery", "Integrity" ], "fieldMix": [ { "field": "Storage systems", "percentage": 60 }, { "field": "Embedded and edge", "percentage": 40 } ], "patterns": [] }, { "id": "12d922db-8d6c-46fc-977f-f6f300f4ec4f", "key": "CJOUR-106", "title": "Roll edge-journal writes onto a new page without overwriting unread events", "type": "TASK", "priority": "HIGH", "difficulty": "INTERMEDIATE", "estimateMinutes": 135, "phaseId": "power", "dependsOn": [ "CJOUR-101", "CJOUR-104", "CJOUR-105" ], "scenario": "Page wrap overwrites unacknowledged events. Separate writable capacity from reclaimable pages.", "acceptanceCriteria": [ "Active unread pages remain protected", "Full journal returns explicit capacity result", "New page starts with validated header" ], "implementationNotes": [ "Do not silently discard oldest readings." ], "verification": [ "Fill to page boundary", "Fill entire journal without acknowledgements" ], "deliverables": [ "Page allocator and full-capacity cases" ], "rollout": "Stop admission when no safe writable page exists.", "skills": [ "Ring buffers", "Resource limits" ], "fieldMix": [ { "field": "Embedded and edge", "percentage": 50 }, { "field": "Storage systems", "percentage": 50 } ], "patterns": [] }, { "id": "db01f212-a266-4994-9d1a-e0796993da8e", "key": "CJOUR-107", "title": "Recover edge-journal page generation selection after power loss", "type": "BUG", "priority": "HIGH", "difficulty": "EXPERT", "estimateMinutes": 240, "phaseId": "power", "dependsOn": [ "CJOUR-105", "CJOUR-106" ], "scenario": "A cut during page-header activation leaves two pages claiming to be newest. Resolve generations through a declared ordering rule.", "acceptanceCriteria": [ "Recovery chooses valid committed generation", "Incomplete header cannot supersede valid page", "Ambiguous generations fail visibly" ], "implementationNotes": [ "Include wrap behavior in generation comparison." ], "verification": [ "Cut header activation", "Exercise generation wrap fixture" ], "deliverables": [ "Generation selection and boundary tests" ], "rollout": "Preserve both pages and stop writes on unresolved ambiguity.", "skills": [ "Crash consistency", "Sequence arithmetic" ], "fieldMix": [ { "field": "Storage systems", "percentage": 60 }, { "field": "Embedded and edge", "percentage": 40 } ], "patterns": [] }, { "id": "e1024784-a659-4fc1-9426-f4426b8a7e8f", "key": "CJOUR-108", "title": "Reclaim edge-journal pages only after durable delivery acknowledgements", "type": "TASK", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 180, "phaseId": "capacity", "dependsOn": [ "CJOUR-103", "CJOUR-107" ], "scenario": "The gateway erases a page after sending bytes, before the receiver acknowledges them. Gate reclamation on durable acknowledgements.", "acceptanceCriteria": [ "Sent-only records remain protected", "Acknowledged complete page may erase", "Crash before acknowledgement persistence keeps page" ], "implementationNotes": [ "Receiver stub must support replay by stable event identity." ], "verification": [ "Acknowledge all page records", "Timeout after receiver acceptance" ], "deliverables": [ "Ack ledger and reclamation cases" ], "rollout": "Pause erasure if acknowledgement state is uncertain.", "skills": [ "Delivery semantics", "Storage" ], "fieldMix": [ { "field": "Storage systems", "percentage": 40 }, { "field": "Embedded and edge", "percentage": 30 }, { "field": "Distributed systems", "percentage": 30 } ], "patterns": [] }, { "id": "7710346a-76da-4620-98bc-ec0ad87291d2", "key": "CJOUR-109", "title": "Batch edge-journal metadata updates within a declared loss window", "type": "CHORE", "priority": "MEDIUM", "difficulty": "ADVANCED", "estimateMinutes": 165, "phaseId": "capacity", "dependsOn": [ "CJOUR-108" ], "scenario": "A metadata write for every status poll causes unnecessary emulated erase work. Batch only nonauthoritative counters.", "acceptanceCriteria": [ "Event commits remain durable", "Batching does not weaken acknowledgement protection", "Counter loss window is documented" ], "implementationNotes": [ "Do not batch safety-critical authority or claim real endurance improvement." ], "verification": [ "Compare emulator operation counts", "Cut power before counter flush" ], "deliverables": [ "Counter batching and measured local trace" ], "rollout": "Disable batching if authority depends on buffered counters.", "skills": [ "Performance", "Durability" ], "fieldMix": [ { "field": "Performance engineering", "percentage": 40 }, { "field": "Storage systems", "percentage": 30 }, { "field": "Embedded and edge", "percentage": 30 } ], "patterns": [] }, { "id": "4d5d951a-fa4c-4fb3-a5d1-8d53858ad443", "key": "CJOUR-110", "title": "Inspect edge-journal pages without modifying recovery state", "type": "STORY", "priority": "MEDIUM", "difficulty": "INTERMEDIATE", "estimateMinutes": 120, "phaseId": "capacity", "dependsOn": [ "CJOUR-107", "CJOUR-109" ], "scenario": "Debugging currently boots the journal and may erase pages. Add a read-only page inspector.", "acceptanceCriteria": [ "Reports generation and commit validity", "Does not erase or rewrite", "Payload display is opt-in" ], "implementationNotes": [ "Restrict input to explicit synthetic image files." ], "verification": [ "Inspect valid image", "Inspect torn and corrupt images" ], "deliverables": [ "Inspector and no-write assertions" ], "rollout": "Keep diagnostic mode read-only if recovery suggestions are uncertain.", "skills": [ "Diagnostics", "Emulation" ], "fieldMix": [ { "field": "Developer tooling", "percentage": 40 }, { "field": "Embedded and edge", "percentage": 30 }, { "field": "Storage systems", "percentage": 30 } ], "patterns": [] } ] } ] }