{ "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": "795f7fba-673b-44f3-9303-2bddca3f6ce8", "key": "ARULE", "title": "Ship a reviewable pricing-rule service", "field": "Backend", "summary": "Version promotional pricing rules and make every applied discount explainable.", "context": "A fictional parts supplier combines contract prices with promotions. Sales needs repeatable quotes when rules change during checkout.", "stack": [ "TypeScript", "PostgreSQL", "JSON Schema" ], "prerequisites": [ "Create synthetic products and integer minor-unit prices.", "Implement a small local quote API." ], "developerValue": "Practice deterministic rule evaluation, revision control and bounded execution.", "companyValue": "Review explainable commercial rules without trusting opaque price changes.", "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": "rules", "title": "Constrain rule input", "goal": "Define a safe, deterministic rule language." }, { "id": "quotes", "title": "Apply frozen rules", "goal": "Make quote decisions consistent and auditable." }, { "id": "release", "title": "Release rule versions", "goal": "Compare revisions and recover rejected releases." } ], "tickets": [ { "id": "fdee872f-bdf8-4d6e-99bd-5c2f4c61aaf1", "key": "ARULE-101", "title": "Define the supported promotion predicates without executable expressions", "type": "TASK", "priority": "MEDIUM", "difficulty": "FOUNDATIONAL", "estimateMinutes": 90, "phaseId": "rules", "dependsOn": [], "scenario": "Sales requested a formula textbox; evaluating arbitrary expressions would make quote behavior difficult to bound and audit.", "acceptanceCriteria": [ "Allow explicit product, quantity and date predicates.", "Reject unknown operators and excessive nesting.", "Publish a schema with accepted and rejected examples." ], "implementationNotes": [ "Treat rule documents as data; never evaluate source strings." ], "verification": [ "Parse a quantity-band promotion.", "Reject a function expression and a nesting-limit violation." ], "deliverables": [ "Promotion schema and parser cases" ], "rollout": "Accept drafts only initially; disable new drafts if parser compatibility fails.", "skills": [ "Schema design", "Input validation" ], "fieldMix": [ { "field": "Backend", "percentage": 60 }, { "field": "API design", "percentage": 20 }, { "field": "Security", "percentage": 20 } ], "patterns": [] }, { "id": "a5b0c45d-fef0-4c27-9c3a-b2c4e56e1027", "key": "ARULE-102", "title": "Resolve overlapping promotions with an explicit tie-break policy", "type": "TASK", "priority": "MEDIUM", "difficulty": "INTERMEDIATE", "estimateMinutes": 150, "phaseId": "rules", "dependsOn": [ "ARULE-101" ], "scenario": "Two promotions match the same part and the chosen discount depends on database return order.", "acceptanceCriteria": [ "Define priority and stable-ID tie breaking.", "Return the winning rule and losing-match reasons.", "Evaluation is independent of input array order." ], "implementationNotes": [ "Use integer arithmetic and a documented rounding boundary." ], "verification": [ "Shuffle matching rules and retain the same price.", "Exercise equal priorities and invalid discount bounds." ], "deliverables": [ "Deterministic resolver and ordering tests" ], "rollout": "Compare decisions on synthetic quotes; retain the previous resolver version for rollback.", "skills": [ "Determinism", "Business rules" ], "fieldMix": [ { "field": "Backend", "percentage": 100 } ], "patterns": [] }, { "id": "98375e52-586d-4fb2-a40e-1203e142ee70", "key": "ARULE-103", "title": "Validate promotion date ranges before publishing drafts", "type": "BUG", "priority": "MEDIUM", "difficulty": "FOUNDATIONAL", "estimateMinutes": 60, "phaseId": "rules", "dependsOn": [ "ARULE-101" ], "scenario": "A promotion with its end before its start passes draft review and can never apply.", "acceptanceCriteria": [ "Require offset-bearing UTC-normalizable dates.", "Reject empty and reversed ranges at publication.", "Display validation paths without raw rule documents in logs." ], "implementationNotes": [ "Use half-open intervals consistently." ], "verification": [ "Publish an adjacent pair of valid promotions.", "Reject reversed, missing-offset and empty intervals." ], "deliverables": [ "Publication date guard" ], "rollout": "Deploy guard for unpublished drafts; preserve existing published versions.", "skills": [ "Validation", "Temporal rules" ], "fieldMix": [ { "field": "Backend", "percentage": 100 } ], "patterns": [] }, { "id": "980cd226-b289-4740-a46d-d629c580c54e", "key": "ARULE-104", "title": "Freeze product and rule versions when a quote is accepted", "type": "STORY", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 240, "phaseId": "quotes", "dependsOn": [ "ARULE-102", "ARULE-103" ], "scenario": "A buyer accepts a quote after a promotion edit and receives a different total from the amount previously displayed.", "acceptanceCriteria": [ "Accepted quotes retain product and rule version identities.", "Acceptance checks expiry and expected quote revision.", "Retries resolve one accepted quote with an unchanged total." ], "implementationNotes": [ "Store a canonical calculation input hash with the quote." ], "verification": [ "Accept a quote after changing current rules and retain its frozen total.", "Attempt acceptance after expiry and create no order." ], "deliverables": [ "Quote acceptance command and frozen-input checks" ], "rollout": "Enable acceptance for synthetic accounts; suspend new acceptance while preserving accepted records.", "skills": [ "Immutability", "Transactions" ], "fieldMix": [ { "field": "Backend", "percentage": 60 }, { "field": "Database engineering", "percentage": 40 } ], "patterns": [] }, { "id": "7da5202d-9e8d-4340-9c2e-51b4a409328f", "key": "ARULE-105", "title": "Bound pricing work for a cart with many matching rules", "type": "TASK", "priority": "MEDIUM", "difficulty": "EXPERT", "estimateMinutes": 300, "phaseId": "quotes", "dependsOn": [ "ARULE-102" ], "scenario": "An unusually broad rule set makes checkout evaluate thousands of predicates per item and blocks unrelated quotes.", "acceptanceCriteria": [ "Set explicit cart, rule-count and predicate-work limits.", "Reject over-budget requests before partial quote publication.", "Return a bounded-work error distinct from invalid pricing." ], "implementationNotes": [ "Choose limits from a repeatable local synthetic workload and document conditions." ], "verification": [ "Measure work counters for 100 items and 200 rules.", "Exceed each limit and verify no accepted quote is created." ], "deliverables": [ "Evaluation budget and reproducible workload" ], "rollout": "Canary limits in observation mode; lower admitted work or restore prior limits on regressions.", "skills": [ "Resource budgets", "Complexity" ], "fieldMix": [ { "field": "Performance engineering", "percentage": 50 }, { "field": "Backend", "percentage": 50 } ], "patterns": [] }, { "id": "2c465eeb-5e2e-4fcf-b8f6-3b4bfe110afc", "key": "ARULE-106", "title": "Keep negotiated account prices outside shared quote caches", "type": "BUG", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 210, "phaseId": "quotes", "dependsOn": [ "ARULE-104" ], "scenario": "A shared cache returns one customer's negotiated rate to another account requesting the same product list.", "acceptanceCriteria": [ "Bind cache identity to organization, account and frozen price version.", "Authorize before cache lookup.", "Never cache an authorization failure as a valid quote." ], "implementationNotes": [ "Include all price-affecting inputs in canonical cache keys." ], "verification": [ "Quote identical carts for two negotiated-price accounts.", "Attempt cross-account access and inspect cache hits and response fields." ], "deliverables": [ "Scoped cache key and isolation regression" ], "rollout": "Invalidate the affected namespace before enabling the new key format.", "skills": [ "Caching", "Tenant isolation" ], "fieldMix": [ { "field": "Security", "percentage": 50 }, { "field": "Backend", "percentage": 50 } ], "patterns": [] }, { "id": "e2ec3343-d95f-4070-87c6-12d2be14835c", "key": "ARULE-107", "title": "Report why a cart missed a promotion without leaking contract terms", "type": "STORY", "priority": "MEDIUM", "difficulty": "INTERMEDIATE", "estimateMinutes": 150, "phaseId": "quotes", "dependsOn": [ "ARULE-102", "ARULE-106" ], "scenario": "Sales wants to explain an unmet minimum quantity, but the current debug endpoint exposes every account's price rules.", "acceptanceCriteria": [ "Explain only rules visible to the requesting account.", "Show failed predicate names with permitted thresholds.", "Omit internal contract identifiers and unrelated rule matches." ], "implementationNotes": [ "Build a dedicated explanation projection." ], "verification": [ "Explain a visible minimum-quantity miss.", "Request explanation for an inaccessible contract and receive no rule details." ], "deliverables": [ "Scoped pricing explanation endpoint" ], "rollout": "Enable the projection for one synthetic sales role; disable debug routes on disclosure failure.", "skills": [ "Authorization", "Explainability" ], "fieldMix": [ { "field": "Security", "percentage": 50 }, { "field": "Backend", "percentage": 30 }, { "field": "API design", "percentage": 20 } ], "patterns": [] }, { "id": "3f224d0f-e9bb-496b-9882-6e58feeb71af", "key": "ARULE-108", "title": "Compare a draft pricing revision against a named quote corpus", "type": "CHORE", "priority": "MEDIUM", "difficulty": "INTERMEDIATE", "estimateMinutes": 180, "phaseId": "release", "dependsOn": [ "ARULE-104", "ARULE-107" ], "scenario": "A promotion revision fixes bulk orders but may unintentionally discount small carts.", "acceptanceCriteria": [ "Create and version a synthetic quote corpus.", "Report old and new totals plus changed rule identities.", "Flag unexplained differences before publication." ], "implementationNotes": [ "The corpus is authored for this exercise; do not claim production coverage." ], "verification": [ "Include bulk, small-cart and no-match examples.", "Insert an invalid draft and report validation failure instead of a comparison." ], "deliverables": [ "Revision comparison command and synthetic corpus" ], "rollout": "Require comparison review for draft publication; preserve earlier reports.", "skills": [ "Regression analysis", "Tooling" ], "fieldMix": [ { "field": "Quality engineering", "percentage": 50 }, { "field": "Backend", "percentage": 30 }, { "field": "Developer tooling", "percentage": 20 } ], "patterns": [] }, { "id": "938e3bdc-4687-4825-b8da-8afe19d99f9b", "key": "ARULE-109", "title": "Publish a pricing revision with optimistic review protection", "type": "STORY", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 240, "phaseId": "release", "dependsOn": [ "ARULE-103", "ARULE-108" ], "scenario": "A reviewer approves a draft while an editor changes its discount; publication currently activates content nobody reviewed.", "acceptanceCriteria": [ "Approval binds the exact canonical draft hash.", "Publication rejects a changed draft or stale expected revision.", "Published rule content cannot be updated in place." ], "implementationNotes": [ "Commit active-pointer selection and audit metadata together." ], "verification": [ "Publish an unchanged approved draft.", "Edit between approval and publish and retain the previous active revision." ], "deliverables": [ "Guarded publication command" ], "rollout": "Publish to synthetic accounts first; restore the prior active pointer without rewriting versions.", "skills": [ "Optimistic concurrency", "Versioning" ], "fieldMix": [ { "field": "Backend", "percentage": 60 }, { "field": "Database engineering", "percentage": 40 } ], "patterns": [] }, { "id": "695efa2c-4a88-4623-8b0b-0d542ac45406", "key": "ARULE-110", "title": "Replay a pricing dispute from immutable quote inputs", "type": "TASK", "priority": "MEDIUM", "difficulty": "EXPERT", "estimateMinutes": 300, "phaseId": "release", "dependsOn": [ "ARULE-104", "ARULE-109" ], "scenario": "Support receives a disputed total after three rule releases and cannot reproduce which calculation the buyer accepted.", "acceptanceCriteria": [ "Replay selects the recorded evaluator and input versions.", "Report missing versions as unreproducible rather than guessing.", "Compare computed total and hash with the accepted record." ], "implementationNotes": [ "Keep replay read-only and use fabricated customer data." ], "verification": [ "Replay an accepted synthetic quote across later releases.", "Remove an available version in the test double and assert explicit failure." ], "deliverables": [ "Read-only dispute replay and failure cases" ], "rollout": "Expose replay to scoped support users; revoke access if provenance cannot be resolved.", "skills": [ "Reproducibility", "Auditability" ], "fieldMix": [ { "field": "Backend", "percentage": 70 }, { "field": "Developer tooling", "percentage": 30 } ], "patterns": [] } ] } ] }