{ "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": [ { "key": "DREL", "title": "Promote one immutable release through every environment", "field": "DevOps", "summary": "Replace rebuild-per-environment delivery with verified artifact promotion and reversible rollout.", "context": "A fictional scheduling API is rebuilt separately for test, staging, and production-like local environments. The resulting images differ, release notes list the branch instead of the artifact, and rollback rebuilds old source with new dependencies. Use a local registry simulator and synthetic deployments; no cluster or customer traffic is supplied.", "stack": [ "TypeScript", "OCI metadata", "Git", "Deployment simulator" ], "prerequisites": [ "Artifact digests", "Release states", "Health checks" ], "developerValue": "Practice immutable promotion, release authority, compatibility gates, canaries, and rollback.", "companyValue": "Review a delivery flow that can identify exactly what is running and restore a known artifact without rebuilding it.", "delivery": "Ten linked tickets across three phases. Use a local repository and fake providers; deliver workflow code, failure tests, a rollback rehearsal, and a concise runbook.", "phases": [ { "id": "baseline", "title": "Make the delivery contract visible", "goal": "Replace implicit workflow assumptions with reviewable inputs and outcomes." }, { "id": "control", "title": "Control change and failure", "goal": "Add bounded concurrency, authority checks, and restart-safe transitions." }, { "id": "handoff", "title": "Operate and improve", "goal": "Measure the workflow, rehearse recovery, and document ownership." } ], "tickets": [ { "id": "6d153361-5f16-43bd-b0d7-8798363d84eb", "key": "DREL-101", "title": "Bind release identity to an artifact digest", "type": "TASK", "priority": "MEDIUM", "difficulty": "FOUNDATIONAL", "estimateMinutes": 90, "phaseId": "baseline", "dependsOn": [], "scenario": "The deployment record stores image:latest and commit branch, so two releases display the same identity after the tag moves.", "acceptanceCriteria": [ "Release stores immutable artifact digest, source revision, and build manifest hash", "Mutable tags resolve to a digest before approval", "Display distinguishes requested tag from deployed digest" ], "implementationNotes": [ "Use the local registry simulator and never pull public images." ], "verification": [ "Resolve and deploy one fixture tag while retaining its digest.", "Move the tag and confirm the approved release identity does not change." ], "deliverables": [ "Immutable release record and moved-tag test" ], "rollout": "Require digest resolution before any environment accepts a new release.", "skills": [ "Artifact identity", "Release metadata" ], "fieldMix": [ { "field": "DevOps", "percentage": 70 }, { "field": "Platform engineering", "percentage": 30 } ], "patterns": [] }, { "id": "7d8aafd3-11b6-4368-bb95-4372cfc5b61b", "key": "DREL-102", "title": "Generate release notes from the promoted revision range", "type": "BUG", "priority": "MEDIUM", "difficulty": "FOUNDATIONAL", "estimateMinutes": 90, "phaseId": "baseline", "dependsOn": [ "DREL-101" ], "scenario": "Notes include commits merged after the artifact was built because they query the current branch head.", "acceptanceCriteria": [ "Notes bind previous and current immutable source revisions", "Each change links to its synthetic pull-request identity", "Empty, missing, and nonancestor ranges have explicit outcomes" ], "implementationNotes": [ "Do not use current branch state after release creation." ], "verification": [ "Generate notes for a declared three-change revision range.", "Advance the branch and confirm the existing notes remain unchanged." ], "deliverables": [ "Revision-bound notes generator and history fixtures" ], "rollout": "Publish notes as draft until artifact and range reconciliation pass.", "skills": [ "Git history", "Release communication" ], "fieldMix": [ { "field": "DevOps", "percentage": 70 }, { "field": "Developer tooling", "percentage": 30 } ], "patterns": [] }, { "id": "eb3f4d08-f1c5-4c5b-8a56-4c7d7fbd8e5b", "key": "DREL-103", "title": "Promote the built artifact instead of rebuilding it", "type": "STORY", "priority": "MEDIUM", "difficulty": "INTERMEDIATE", "estimateMinutes": 150, "phaseId": "baseline", "dependsOn": [ "DREL-101" ], "scenario": "Staging and production-like environments run images compiled at different times from the same source label.", "acceptanceCriteria": [ "Build creates one content-addressed artifact", "Promotion changes environment references without changing bytes", "Environment record retains promotion actor, time, and source environment" ], "implementationNotes": [ "Configuration remains external and versioned; it is not baked differently into each image." ], "verification": [ "Promote one digest through two fixture environments and compare bytes.", "Attempt promotion with a mismatching manifest and block the transition." ], "deliverables": [ "Promotion command and byte-identity tests" ], "rollout": "Adopt from test to staging before changing the final environment.", "skills": [ "Artifact promotion", "Immutability" ], "fieldMix": [ { "field": "DevOps", "percentage": 70 }, { "field": "Cloud infrastructure", "percentage": 30 } ], "patterns": [] }, { "id": "a353edb1-9ede-4d47-b034-85a0d7751dc1", "key": "DREL-104", "title": "Gate promotion on database compatibility", "type": "CHORE", "priority": "MEDIUM", "difficulty": "INTERMEDIATE", "estimateMinutes": 150, "phaseId": "control", "dependsOn": [ "DREL-103" ], "scenario": "A release expects a renamed column while rollback still expects the old one, making the nominal rollback artifact unusable.", "acceptanceCriteria": [ "Manifest declares required and provided schema compatibility window", "Promotion checks current environment schema before deployment", "Rollback target is validated against post-migration schema" ], "implementationNotes": [ "Use fixture schema versions; do not execute migrations against a real database." ], "verification": [ "Promote an expand-compatible release and validate its rollback target.", "Attempt a contract-first release and show the gate identifies the incompatible direction." ], "deliverables": [ "Schema compatibility gate and rollout matrix" ], "rollout": "Require expand, migrate, contract phases for destructive changes.", "skills": [ "Database migrations", "Compatibility", "Rollback planning" ], "fieldMix": [ { "field": "DevOps", "percentage": 60 }, { "field": "Database engineering", "percentage": 40 } ], "patterns": [] }, { "id": "23cfe1d5-b2bc-49c8-a618-9ef36e17940c", "key": "DREL-105", "title": "Canary one cohort with a measurable abort rule", "type": "TASK", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 240, "phaseId": "control", "dependsOn": [ "DREL-103", "DREL-104" ], "scenario": "A canary is called healthy because no one watched it for long, despite a synthetic error spike in one endpoint.", "acceptanceCriteria": [ "Canary binds cohort, duration, traffic minimum, and comparison baseline", "Abort evaluates declared error and latency thresholds", "Insufficient observations remain inconclusive" ], "implementationNotes": [ "Use deterministic synthetic traffic; thresholds apply only to this exercise." ], "verification": [ "Run a healthy canary through the full observation window.", "Inject an endpoint-specific regression and confirm automatic halt before wider rollout." ], "deliverables": [ "Canary policy, evaluator, and regression fixtures" ], "rollout": "Expand only after a conclusive passing result.", "skills": [ "Progressive delivery", "Release analysis" ], "fieldMix": [ { "field": "DevOps", "percentage": 60 }, { "field": "Site reliability", "percentage": 40 } ], "patterns": [] }, { "id": "f95388c5-7823-4bd0-9c23-9b3d54c0e678", "key": "DREL-106", "title": "Pause a release when deployment state drifts", "type": "BUG", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 240, "phaseId": "control", "dependsOn": [ "DREL-103" ], "scenario": "A manual fixture change replaces one replica image, but the release controller continues and records the target digest as complete.", "acceptanceCriteria": [ "Reconciliation compares desired and observed digest per instance", "Unexpected drift pauses rollout and identifies affected instances", "Repair requires an explicit decision to restore desired state or adopt a new release" ], "implementationNotes": [ "Do not overwrite drift before recording it." ], "verification": [ "Complete a rollout whose observations match the release.", "Change one instance out of band and confirm the controller pauses without erasing evidence." ], "deliverables": [ "Drift detector and paused-release flow" ], "rollout": "Begin with report-only drift detection in the simulator.", "skills": [ "Reconciliation", "Configuration drift" ], "fieldMix": [ { "field": "DevOps", "percentage": 70 }, { "field": "Platform engineering", "percentage": 30 } ], "patterns": [] }, { "id": "af9474f3-ffe4-4f1d-a560-d1143b6f58a8", "key": "DREL-107", "title": "Authorize release approval for the exact artifact", "type": "STORY", "priority": "HIGH", "difficulty": "EXPERT", "estimateMinutes": 360, "phaseId": "control", "dependsOn": [ "DREL-101", "DREL-105" ], "scenario": "An approval made for one digest remains valid after the release record is edited to point at another artifact.", "acceptanceCriteria": [ "Approval binds artifact digest, environment, policy version, and expiry", "Any bound-field change invalidates approval", "Requester cannot satisfy a required independent approval role" ], "implementationNotes": [ "Use synthetic identities and permissions; this is workflow authorization, not proof of code authorship." ], "verification": [ "Approve and promote the exact eligible release.", "Change digest and replay the approval token, then verify denial and audit." ], "deliverables": [ "Release approval boundary and replay tests" ], "rollout": "Require explicit approval for the final simulated environment first.", "skills": [ "Authorization", "Release governance", "Audit" ], "fieldMix": [ { "field": "DevOps", "percentage": 60 }, { "field": "Security", "percentage": 40 } ], "patterns": [] }, { "id": "f4b2bfa9-4da7-4896-86e6-9c8f99554548", "key": "DREL-108", "title": "Rollback to a known artifact without rebuilding source", "type": "CHORE", "priority": "HIGH", "difficulty": "ADVANCED", "estimateMinutes": 240, "phaseId": "handoff", "dependsOn": [ "DREL-104", "DREL-105", "DREL-106" ], "scenario": "The rollback command checks out an old tag and rebuilds it with current dependencies, producing bytes never previously tested.", "acceptanceCriteria": [ "Rollback selects a previously promoted immutable digest", "Compatibility gate evaluates current schema and configuration", "Release history records the failed and restored identities" ], "implementationNotes": [ "Rollback does not delete the failed artifact or rewrite its record." ], "verification": [ "Roll forward, trigger the abort rule, and restore the exact prior digest.", "Remove the prior artifact from the registry fixture and block rollback with a recovery instruction." ], "deliverables": [ "Digest-based rollback command and rehearsal" ], "rollout": "Maintain at least one verified compatible rollback target per environment.", "skills": [ "Rollback", "Artifact retention", "Incident response" ], "fieldMix": [ { "field": "DevOps", "percentage": 70 }, { "field": "Site reliability", "percentage": 30 } ], "patterns": [] }, { "id": "c1ba6b1b-9de4-4ae3-a869-01afe8558711", "key": "DREL-109", "title": "Resume promotion after the registry response disappears", "type": "TASK", "priority": "HIGH", "difficulty": "EXPERT", "estimateMinutes": 360, "phaseId": "handoff", "dependsOn": [ "DREL-103", "DREL-108" ], "scenario": "The registry accepts a promotion tag and drops the response; retry sees the tag but cannot tell whether it was created by this operation.", "acceptanceCriteria": [ "Promotion uses deterministic operation identity", "Retry reads digest and operation metadata before mutation", "Conflicting existing tag becomes visible and blocks automatic continuation" ], "implementationNotes": [ "The registry adapter is local and provider responses are treated as untrusted input." ], "verification": [ "Promote and replay one operation with the same result.", "Drop the acceptance response and separately precreate a conflicting tag." ], "deliverables": [ "Idempotent promotion adapter and ambiguity tests" ], "rollout": "Enable one registry namespace while retaining digest-only deployment.", "skills": [ "Idempotency", "Registry APIs", "Recovery" ], "fieldMix": [ { "field": "DevOps", "percentage": 60 }, { "field": "Integrations", "percentage": 40 } ], "patterns": [] }, { "id": "8f4e8668-22ec-4080-af14-1aea48e1da60", "key": "DREL-110", "title": "Publish a release ledger that answers what is running", "type": "BUG", "priority": "MEDIUM", "difficulty": "INTERMEDIATE", "estimateMinutes": 150, "phaseId": "handoff", "dependsOn": [ "DREL-102", "DREL-106", "DREL-108", "DREL-109" ], "scenario": "During a rehearsal, responders compare commit hashes from logs because there is no single view of release, artifact, configuration, and schema identity.", "acceptanceCriteria": [ "Ledger shows desired and observed artifact per environment", "Entries include configuration and schema compatibility identities", "Failed, paused, rolled-back, and superseded releases remain inspectable" ], "implementationNotes": [ "The ledger is append-oriented planning and operational data; it is not candidate evidence." ], "verification": [ "Trace a promotion, pause, and rollback from ledger entries.", "Remove an observation and confirm the view displays uncertainty rather than inferred state." ], "deliverables": [ "Release ledger projection and responder guide" ], "rollout": "Use the ledger during a full local rollback rehearsal before handoff.", "skills": [ "Release observability", "Audit trails", "Runbooks" ], "fieldMix": [ { "field": "DevOps", "percentage": 70 }, { "field": "Site reliability", "percentage": 30 } ], "patterns": [] } ], "id": "92ac7bad-92e7-478c-b25e-6cd40d07548c" } ] }