{ "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": "ad1d2a4c-4a0a-4163-b967-e66fda0e3ab0", "key": "BCALENDAR", "title": "Calendar availability synchronization", "field": "Integrations", "summary": "Reconcile availability and event changes across a scheduling app and a local calendar provider.", "context": "A fictional booking service supports consultants in multiple time zones. Recurring events, revoked access, and delayed callbacks cause missed conflicts.", "stack": [ "TypeScript", "iCalendar", "HTTP" ], "prerequisites": [ "Author synthetic calendars and a local provider double with recurrence, timezone, and access-revocation cases." ], "developerValue": "Practice temporal modeling, synchronization lifecycles, and privacy-preserving projections.", "companyValue": "Reduce scheduling ambiguity through explicit availability contracts and recoverable synchronization.", "delivery": "Deliver local availability calculations and sync behavior; send no invitations or calendar writes externally.", "phases": [ { "id": "time", "title": "Define temporal semantics", "goal": "Model instants, zones, and recurrence." }, { "id": "sync", "title": "Synchronize availability", "goal": "Handle event updates and provider failures." }, { "id": "release", "title": "Rehearse edge cases", "goal": "Verify privacy, cutover, and recovery." } ], "tickets": [ { "id": "62dacf22-0cf9-45d2-9a55-afa5c7c606aa", "key": "BCALENDAR-101", "title": "Distinguish all-day events from timed calendar intervals", "type": "TASK", "priority": "MEDIUM", "difficulty": "FOUNDATIONAL", "estimateMinutes": 60, "phaseId": "time", "dependsOn": [], "scenario": "An all-day absence becomes a twenty-four-hour UTC interval and shifts across local dates.", "acceptanceCriteria": [ "Represent all-day dates separately from instants.", "Declare exclusive end semantics.", "Preserve the event's timezone context." ], "implementationNotes": [ "Do not infer an event zone from the server timezone." ], "verification": [ "Render a timed event and all-day absence correctly.", "Reject missing timezone context for ambiguous local times." ], "deliverables": [ "Temporal data contract." ], "rollout": "Version the contract before importing calendar records.", "skills": [ "Time modeling" ], "fieldMix": [ { "field": "Integrations", "percentage": 60 }, { "field": "Backend", "percentage": 40 } ], "patterns": [] }, { "id": "9cb30c75-0c33-4e96-9c10-35f15f6e15f9", "key": "BCALENDAR-102", "title": "Resolve daylight-saving gaps and repeated local times", "type": "TASK", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 180, "phaseId": "time", "dependsOn": [ "BCALENDAR-101" ], "scenario": "A recurring appointment lands in a nonexistent local hour during a timezone transition.", "acceptanceCriteria": [ "Define explicit gap and overlap policies.", "Keep original local time and selected offset.", "Return ambiguity when policy cannot resolve the occurrence." ], "implementationNotes": [ "Use a maintained timezone database available locally." ], "verification": [ "Exercise a spring gap and autumn repeated hour.", "Reject a silently guessed offset." ], "deliverables": [ "Timezone resolution tests." ], "rollout": "Keep affected appointments unresolved until policy is applied.", "skills": [ "Time zones" ], "fieldMix": [ { "field": "Backend", "percentage": 60 }, { "field": "Integrations", "percentage": 40 } ], "patterns": [] }, { "id": "5e1871f5-fbed-4eee-b3d6-e74066dfeebd", "key": "BCALENDAR-103", "title": "Expand recurrence within a bounded availability window", "type": "TASK", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 210, "phaseId": "time", "dependsOn": [ "BCALENDAR-102" ], "scenario": "An unbounded recurrence rule exhausts the availability request.", "acceptanceCriteria": [ "Require finite query start and end.", "Limit emitted occurrences and processing work.", "Honor exclusions and changed single occurrences." ], "implementationNotes": [ "Reject unsupported recurrence forms explicitly." ], "verification": [ "Expand a weekly rule with an exception.", "Bound an excessive recurrence and reject unsupported syntax." ], "deliverables": [ "Bounded recurrence engine." ], "rollout": "Start with declared supported rules; preserve unsupported events as unavailable context.", "skills": [ "Recurrence", "Resource bounds" ], "fieldMix": [ { "field": "Integrations", "percentage": 40 }, { "field": "Performance engineering", "percentage": 40 }, { "field": "Backend", "percentage": 20 } ], "patterns": [] }, { "id": "78089c42-aaa5-4b14-8cd2-8b6714f691fe", "key": "BCALENDAR-104", "title": "Apply event revisions without reviving cancelled occurrences", "type": "BUG", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 180, "phaseId": "sync", "dependsOn": [ "BCALENDAR-103" ], "scenario": "An old series update recreates a cancelled individual appointment.", "acceptanceCriteria": [ "Track series and occurrence revisions separately.", "Preserve cancellation tombstones.", "Ignore stale updates with an observable reason." ], "implementationNotes": [ "Arrival order is not event version authority." ], "verification": [ "Update one occurrence in a series.", "Replay an older series update after cancellation." ], "deliverables": [ "Revision-aware event importer." ], "rollout": "Adopt on synthetic calendars first; reconcile before enabling booking decisions.", "skills": [ "Event ordering" ], "fieldMix": [ { "field": "Distributed systems", "percentage": 50 }, { "field": "Integrations", "percentage": 50 } ], "patterns": [] }, { "id": "867f52a6-2787-491a-87c8-ad055a0d5980", "key": "BCALENDAR-105", "title": "Use incremental sync tokens without losing full-resync coverage", "type": "TASK", "priority": "HIGH", "difficulty": "INTERMEDIATE", "estimateMinutes": 150, "phaseId": "sync", "dependsOn": [ "BCALENDAR-104" ], "scenario": "The provider invalidates a sync token, and the app interprets it as an empty calendar.", "acceptanceCriteria": [ "Distinguish token invalidation from no changes.", "Start a bounded full sync on invalidation.", "Keep existing availability marked stale until replacement completes." ], "implementationNotes": [ "Never clear events because a provider request failed." ], "verification": [ "Apply a normal incremental page.", "Invalidate the token and preserve stale records during recovery." ], "deliverables": [ "Sync-token recovery." ], "rollout": "Pause definitive availability claims while full sync is incomplete.", "skills": [ "Synchronization" ], "fieldMix": [ { "field": "Integrations", "percentage": 60 }, { "field": "Site reliability", "percentage": 40 } ], "patterns": [] }, { "id": "9a37b006-7826-4fd0-bf6e-ee6b851125e8", "key": "BCALENDAR-106", "title": "Project busy intervals without exposing event descriptions", "type": "TASK", "priority": "HIGH", "difficulty": "INTERMEDIATE", "estimateMinutes": 150, "phaseId": "sync", "dependsOn": [ "BCALENDAR-104" ], "scenario": "Availability responses leak private appointment titles to bookers.", "acceptanceCriteria": [ "Expose only necessary busy intervals.", "Scope calendars by current access grants.", "Exclude titles, attendees, and notes from public projections." ], "implementationNotes": [ "Private provider fields remain outside scheduling responses." ], "verification": [ "Compute availability from authorized events.", "Seed sensitive markers and verify they never appear in outputs." ], "deliverables": [ "Privacy-preserving availability projection." ], "rollout": "Replace detailed projections before public availability is enabled.", "skills": [ "Privacy", "API projections" ], "fieldMix": [ { "field": "Privacy engineering", "percentage": 60 }, { "field": "API design", "percentage": 40 } ], "patterns": [] }, { "id": "47fe39d9-47d3-465e-9042-cb7dadb918a1", "key": "BCALENDAR-107", "title": "Stop provider calls immediately after access revocation", "type": "BUG", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 180, "phaseId": "sync", "dependsOn": [ "BCALENDAR-105", "BCALENDAR-106" ], "scenario": "Revoked calendars remain cached and continue receiving background refreshes.", "acceptanceCriteria": [ "Invalidate active grants and queued refresh authority.", "Suppress cached private availability after revocation.", "Make reconnect an explicit new authorization flow." ], "implementationNotes": [ "Do not retry authorization failures as transient errors." ], "verification": [ "Refresh an authorized calendar.", "Revoke access mid-queue and verify no further authorized reads occur." ], "deliverables": [ "Revocation handling." ], "rollout": "Fail closed on uncertain grants; retain only allowed operational metadata.", "skills": [ "Authorization", "Lifecycle" ], "fieldMix": [ { "field": "Security", "percentage": 50 }, { "field": "Privacy engineering", "percentage": 30 }, { "field": "Integrations", "percentage": 20 } ], "patterns": [] }, { "id": "cbef8f7e-533d-4d35-af78-6248144aa474", "key": "BCALENDAR-108", "title": "Detect overlapping booking attempts against one availability revision", "type": "TASK", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 210, "phaseId": "release", "dependsOn": [ "BCALENDAR-106", "BCALENDAR-107" ], "scenario": "Two bookers see the same open slot before either reservation is committed.", "acceptanceCriteria": [ "Bind booking checks to a declared availability revision.", "Serialize or atomically reject overlapping local reservations.", "Represent external confirmation as pending when unknown." ], "implementationNotes": [ "Use a local provider double; create no real events." ], "verification": [ "Race two bookings for one slot.", "Change provider availability during booking and expose the conflict." ], "deliverables": [ "Booking consistency checks." ], "rollout": "Keep short local reservations; reconcile unknown external outcomes before releasing them.", "skills": [ "Concurrency", "Scheduling" ], "fieldMix": [ { "field": "Database engineering", "percentage": 40 }, { "field": "Integrations", "percentage": 30 }, { "field": "Distributed systems", "percentage": 30 } ], "patterns": [] }, { "id": "8a13fb19-bb75-438d-9f93-6805759ac562", "key": "BCALENDAR-109", "title": "Assess polling versus callbacks for calendar freshness", "type": "TASK", "priority": "HIGH", "difficulty": "EXPERT", "estimateMinutes": 300, "phaseId": "release", "dependsOn": [ "BCALENDAR-105", "BCALENDAR-108" ], "scenario": "The provider's callbacks are delayed, but frequent polling consumes the request budget.", "acceptanceCriteria": [ "Compare bounded polling and callback-assisted approaches.", "Declare acceptable staleness and request-budget assumptions.", "Rehearse dropped callbacks, duplicates, and provider outages." ], "implementationNotes": [ "Local measurements do not establish a live provider's delivery guarantees." ], "verification": [ "Recover a missed callback through polling.", "Exhaust the budget and show stale availability explicitly." ], "deliverables": [ "Freshness tradeoff assessment." ], "rollout": "Adopt a conservative refresh policy with visible age and a manual recovery path.", "skills": [ "System tradeoffs", "Integration reliability" ], "fieldMix": [ { "field": "System design", "percentage": 40 }, { "field": "Integrations", "percentage": 30 }, { "field": "Site reliability", "percentage": 30 } ], "patterns": [] }, { "id": "193ed6f0-b1ad-454d-8e0c-934918b78f7c", "key": "BCALENDAR-110", "title": "Write the calendar recovery checklist for invalid sync state", "type": "CHORE", "priority": "LOW", "difficulty": "FOUNDATIONAL", "estimateMinutes": 60, "phaseId": "release", "dependsOn": [ "BCALENDAR-109" ], "scenario": "Support needs to recover a calendar without deleting local reservations.", "acceptanceCriteria": [ "Identify the calendar, grant, and sync revision.", "Show safe resync and status commands.", "Preserve local reservations while replacing imported events." ], "implementationNotes": [ "No direct lifecycle-state edits." ], "verification": [ "Recover an invalid token using the guide.", "Reject recovery for a revoked grant." ], "deliverables": [ "Calendar support runbook." ], "rollout": "Rehearse against synthetic calendars before enabling a support action.", "skills": [ "Runbooks" ], "fieldMix": [ { "field": "Site reliability", "percentage": 60 }, { "field": "Integrations", "percentage": 40 } ], "patterns": [] } ] } ] }