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athola\n\nSummary: Applies CQRS and Event Sourcing for read/write separation and audit trails\n\nTags: latest:1.9.19\n\nVersion history:\n\nv1.9.19 | 2026-08-26T13:05:01.256Z | user\n\nRelease v1.9.19\n\nv1.9.18 | 2026-08-15T21:28:59.341Z | user\n\nRelease v1.9.18\n\nv1.9.17 | 2026-07-30T05:28:49.006Z | user\n\nRelease v1.9.17\n\nv1.9.16 | 2026-07-14T19:45:57.363Z | user\n\nRelease v1.9.16\n\nv1.9.15 | 2026-07-04T21:20:08.814Z | user\n\nRelease v1.9.15\n\nv1.9.14 | 2026-06-30T17:50:43.018Z | user\n\nRelease v1.9.14\n\nv1.9.13 | 2026-06-27T16:15:14.759Z | user\n\nRelease v1.9.13\n\nv1.9.12 | 2026-06-19T03:08:33.321Z | user\n\nRelease v1.9.12\n\nv1.8.6 | 2026-06-07T21:22:34.080Z | user\n\nRelease v1.9.11\n\nv1.8.5 | 2026-05-09T02:15:18.485Z | user\n\nRelease v1.9.5\n\nv1.8.4 | 2026-05-06T14:15:02.462Z | user\n\nRelease v1.9.4\n\nv1.8.3 | 2026-04-10T05:45:29.252Z | user\n\nRelease v1.8.3\n\nv1.8.2 | 2026-04-06T22:06:47.178Z | user\n\nRelease v1.8.2\n\nvv1.8.2 | 2026-04-06T16:19:16.290Z | user\n\nRelease v1.8.2\n\nArchive index:\n\nArchive v1.9.19: 3 files, 3729 bytes\n\nFiles: skill-card.md (2332b), SKILL.md (4364b), _meta.json (163b)\n\nFile v1.9.19:SKILL.md\n\n---\nname: architecture-paradigm-cqrs-es\ndescription: Applies CQRS and Event Sourcing for read/write separation and audit trails\nversion: 1.9.8\ntriggers:\n  - architecture\n  - CQRS\n  - Event-Sourcing\n  - distributed-systems\n  - audit-trail\n  - scalability\n  - designing systems with complex domain logic or full state-change history\nmetadata: {\"openclaw\": {\"homepage\": \"https://github.com/athola/claude-night-market/tree/master/plugins/archetypes\", \"emoji\": \"\\ud83c\\udfd7\\ufe0f\"}}\nsource: claude-night-market\nsource_plugin: archetypes\n---\n\n> **Night Market Skill** — ported from [claude-night-market/archetypes](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes). For the full experience with agents, hooks, and commands, install the Claude Code plugin.\n\n\n# The CQRS and Event Sourcing Paradigm\n\n\n## When To Use\n\n- Designing event-sourced systems with complex domain logic\n- Systems requiring full audit trails of state changes\n\n## When NOT To Use\n\n- Simple CRUD applications without complex domain logic\n- Small projects where event sourcing adds unnecessary complexity\n\n## When to Employ This Paradigm\n- When read and write workloads have vastly different performance characteristics or scaling requirements.\n- When all business events must be captured in a durable, immutable history or audit trail.\n- When a business needs to rebuild projections of data or support temporal queries (e.g., \"What did the state of this entity look like yesterday?\").\n\n## Adoption Steps\n1. **Identify Aggregates**: Following Domain-Driven Design principles, specify the bounded contexts and the business invariants that each command must enforce on an aggregate.\n2. **Model Commands and Events**: Define the schemas and validation rules for all commands and the events they produce. Document a clear strategy for versioning and schema evolution.\n3. **Implement the Write Side (Command Side)**: Command handlers are responsible for loading an aggregate's event stream, executing business logic, and atomically appending new events to the stream.\n4. **Build Projections to the Read Side**: Create separate read models (projections) that are fed by subscriptions to the event stream. Implement back-pressure and retry policies for these subscriptions.\n5. **validate Full Observability**: Implement detailed logging that includes event IDs, sequence numbers, and metrics for tracking the lag time of each projection.\n\n## Key Deliverables\n- An Architecture Decision Record (ADR) detailing the aggregates, the chosen event store technology, the projection strategy, and the expected data consistency model (e.g., eventual consistency SLAs).\n- A suite of tests for command handlers that use in-memory event streams, complemented by integration tests for the projections.\n- Operational tooling for replaying events, taking state snapshots for performance, and managing schema migrations.\n\n## Risks & Mitigations\n- **High Operational Overhead**:\n  - **Mitigation**: Bugs related to event ordering and replays can be difficult to diagnose. Invest heavily in automation, Dead-Letter Queues (DLQs) for failed events, and regular \"chaos engineering\" drills to test resilience.\n- **Challenges of Eventual Consistency**:\n  - **Mitigation**: Users may be confused by delays between performing an action and seeing the result. Clearly document the SLAs for read model updates and manage user-facing expectations accordingly, for example, by providing immediate feedback on the command side.\n- **Schema Drift**:\n  - **Mitigation**: An unplanned change to an event schema can break consumers. Enforce the use of a formal schema registry and implement version gates in the CI/CD pipeline to prevent the emission of unvalidated event versions.\n\n## Concrete Components\n\nThese vocabulary items name the concrete tools and abstractions\nthat show up when the paradigm is implemented. They are not\nrequired dependencies and they are not part of the skill's\n``tools:`` frontmatter (which is reserved for Claude Code tool\nrestrictions). Use this list to disambiguate during architecture\ndiscussions.\n\n- ``event-store`` -- append-only log of domain events; the system of record from which projections are built\n- ``message-broker`` -- carries commands and integration events between bounded contexts\n- ``projection-builder`` -- rebuilds read-side views by replaying the event store\n\nFile v1.9.19:_meta.json\n\n{\n  \"ownerId\": \"kn7d107jg9jv602h9ytsegydq184a42s\",\n  \"slug\": \"nm-archetypes-architecture-paradigm-cqrs-es\",\n  \"version\": \"1.9.19\",\n  \"publishedAt\": 1787749501256\n}\n\nFile v1.9.19:skill-card.md\n\n## Description:\n\nApplies CQRS and Event Sourcing for read/write separation and audit trails.\n\nThis skill is ready for commercial/non-commercial use.\n\n## Publisher:\n\n[athola](https://clawhub.ai/user/athola)\n\n### License/Terms of Use:\n\nMIT-0\n\n## Use Case:\n\nDevelopers and engineers use this skill during architecture discussions to decide when CQRS and Event Sourcing fit systems with complex domain logic, separated read and write workloads, durable audit trails, or projection rebuild needs.\n\n### Deployment Geography for Use:\n\nGlobal\n\n## Known Risks and Mitigations:\n\nRisk: The skill may surface during broad architecture or scalability discussions where CQRS and Event Sourcing are not the right default.\n\nMitigation: Treat the guidance as pattern-specific and first confirm needs such as complex domain logic, separated read and write workloads, durable audit trails, or projection rebuilds.\n\nRisk: CQRS and Event Sourcing can add operational overhead through event ordering, replay, projection lag, and recovery workflows.\n\nMitigation: Use automation, dead-letter handling, projection monitoring, replay tooling, and documented consistency expectations before adopting the pattern.\n\nRisk: Event schema changes can break consumers or projections.\n\nMitigation: Define event schemas and versioning rules up front, and use validation gates before new event versions are emitted.\n\n## Reference(s):\n\n- [ClawHub skill page](https://clawhub.ai/athola/skills/nm-archetypes-architecture-paradigm-cqrs-es)\n- [Night Market archetypes source](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes)\n\n## Skill Output:\n\n**Output Type(s):** [Guidance, Markdown]\n\n**Output Format:** [Markdown prose with architecture adoption steps, deliverables, component vocabulary, risks, and mitigations.]\n\n**Output Parameters:** [1D]\n\n**Other Properties Related to Output:** [Non-executable architecture guidance; no API keys, MCP tools, or shell commands detected.]\n\n## Skill Version(s):\n\n1.9.19 (source: server release evidence; artifact frontmatter reports 1.9.8)\n\n## Ethical Considerations:\n\nUsers should evaluate whether this skill is appropriate for their environment, review any generated or modified files before relying on them, and apply their organization's safety, security, and compliance requirements before deployment.\n\nArchive v1.9.18: 3 files, 3667 bytes\n\nFiles: skill-card.md (2172b), SKILL.md (4364b), _meta.json (163b)\n\nFile v1.9.18:SKILL.md\n\n---\nname: architecture-paradigm-cqrs-es\ndescription: Applies CQRS and Event Sourcing for read/write separation and audit trails\nversion: 1.9.8\ntriggers:\n  - architecture\n  - CQRS\n  - Event-Sourcing\n  - distributed-systems\n  - audit-trail\n  - scalability\n  - designing systems with complex domain logic or full state-change history\nmetadata: {\"openclaw\": {\"homepage\": \"https://github.com/athola/claude-night-market/tree/master/plugins/archetypes\", \"emoji\": \"\\ud83c\\udfd7\\ufe0f\"}}\nsource: claude-night-market\nsource_plugin: archetypes\n---\n\n> **Night Market Skill** — ported from [claude-night-market/archetypes](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes). For the full experience with agents, hooks, and commands, install the Claude Code plugin.\n\n\n# The CQRS and Event Sourcing Paradigm\n\n\n## When To Use\n\n- Designing event-sourced systems with complex domain logic\n- Systems requiring full audit trails of state changes\n\n## When NOT To Use\n\n- Simple CRUD applications without complex domain logic\n- Small projects where event sourcing adds unnecessary complexity\n\n## When to Employ This Paradigm\n- When read and write workloads have vastly different performance characteristics or scaling requirements.\n- When all business events must be captured in a durable, immutable history or audit trail.\n- When a business needs to rebuild projections of data or support temporal queries (e.g., \"What did the state of this entity look like yesterday?\").\n\n## Adoption Steps\n1. **Identify Aggregates**: Following Domain-Driven Design principles, specify the bounded contexts and the business invariants that each command must enforce on an aggregate.\n2. **Model Commands and Events**: Define the schemas and validation rules for all commands and the events they produce. Document a clear strategy for versioning and schema evolution.\n3. **Implement the Write Side (Command Side)**: Command handlers are responsible for loading an aggregate's event stream, executing business logic, and atomically appending new events to the stream.\n4. **Build Projections to the Read Side**: Create separate read models (projections) that are fed by subscriptions to the event stream. Implement back-pressure and retry policies for these subscriptions.\n5. **validate Full Observability**: Implement detailed logging that includes event IDs, sequence numbers, and metrics for tracking the lag time of each projection.\n\n## Key Deliverables\n- An Architecture Decision Record (ADR) detailing the aggregates, the chosen event store technology, the projection strategy, and the expected data consistency model (e.g., eventual consistency SLAs).\n- A suite of tests for command handlers that use in-memory event streams, complemented by integration tests for the projections.\n- Operational tooling for replaying events, taking state snapshots for performance, and managing schema migrations.\n\n## Risks & Mitigations\n- **High Operational Overhead**:\n  - **Mitigation**: Bugs related to event ordering and replays can be difficult to diagnose. Invest heavily in automation, Dead-Letter Queues (DLQs) for failed events, and regular \"chaos engineering\" drills to test resilience.\n- **Challenges of Eventual Consistency**:\n  - **Mitigation**: Users may be confused by delays between performing an action and seeing the result. Clearly document the SLAs for read model updates and manage user-facing expectations accordingly, for example, by providing immediate feedback on the command side.\n- **Schema Drift**:\n  - **Mitigation**: An unplanned change to an event schema can break consumers. Enforce the use of a formal schema registry and implement version gates in the CI/CD pipeline to prevent the emission of unvalidated event versions.\n\n## Concrete Components\n\nThese vocabulary items name the concrete tools and abstractions\nthat show up when the paradigm is implemented. They are not\nrequired dependencies and they are not part of the skill's\n``tools:`` frontmatter (which is reserved for Claude Code tool\nrestrictions). Use this list to disambiguate during architecture\ndiscussions.\n\n- ``event-store`` -- append-only log of domain events; the system of record from which projections are built\n- ``message-broker`` -- carries commands and integration events between bounded contexts\n- ``projection-builder`` -- rebuilds read-side views by replaying the event store\n\nFile v1.9.18:_meta.json\n\n{\n  \"ownerId\": \"kn7d107jg9jv602h9ytsegydq184a42s\",\n  \"slug\": \"nm-archetypes-architecture-paradigm-cqrs-es\",\n  \"version\": \"1.9.18\",\n  \"publishedAt\": 1786829339341\n}\n\nFile v1.9.18:skill-card.md\n\n## Description:\n\nApplies CQRS and Event Sourcing for read/write separation and audit trails\n\nThis skill is ready for commercial/non-commercial use.\n\n## Publisher:\n\n[athola](https://clawhub.ai/user/athola)\n\n### License/Terms of Use:\n\nMIT-0\n\n## Use Case:\n\nDevelopers and architects use this skill to evaluate when CQRS and Event Sourcing fit a system, then outline aggregates, commands, events, projections, audit trails, and operational safeguards.\n\n### Deployment Geography for Use:\n\nGlobal\n\n## Known Risks and Mitigations:\n\nRisk: The broad architecture trigger may activate the skill during general design conversations where CQRS or Event Sourcing guidance is not needed.\n\nMitigation: Review whether the trigger set should be narrowed before deployment, and apply the skill only when the user is designing systems with complex domain logic, audit history, or separate read/write scaling needs.\n\nRisk: CQRS and Event Sourcing can add operational overhead, eventual consistency concerns, and event schema drift if applied to simple CRUD systems.\n\nMitigation: Use the skill's own fit criteria before adopting the pattern, and require clear event versioning, projection monitoring, replay procedures, and user-facing consistency expectations.\n\n## Reference(s):\n\n- [ClawHub skill page](https://clawhub.ai/athola/skills/nm-archetypes-architecture-paradigm-cqrs-es)\n- [Project homepage](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes)\n\n## Skill Output:\n\n**Output Type(s):** [text, markdown, code, configuration, guidance]\n\n**Output Format:** [Markdown guidance with architecture recommendations, deliverables, and implementation considerations]\n\n**Output Parameters:** [1D]\n\n**Other Properties Related to Output:** [Documentation-only guidance; no executable tools, commands, or environment variables are declared.]\n\n## Skill Version(s):\n\n1.9.18 (source: server release evidence)\n\n## Ethical Considerations:\n\nUsers should evaluate whether this skill is appropriate for their environment, review any generated or modified files before relying on them, and apply their organization's safety, security, and compliance requirements before deployment.\n\nArchive v1.9.17: 3 files, 3658 bytes\n\nFiles: skill-card.md (2135b), SKILL.md (4364b), _meta.json (163b)\n\nFile v1.9.17:SKILL.md\n\n---\nname: architecture-paradigm-cqrs-es\ndescription: Applies CQRS and Event Sourcing for read/write separation and audit trails\nversion: 1.9.8\ntriggers:\n  - architecture\n  - CQRS\n  - Event-Sourcing\n  - distributed-systems\n  - audit-trail\n  - scalability\n  - designing systems with complex domain logic or full state-change history\nmetadata: {\"openclaw\": {\"homepage\": \"https://github.com/athola/claude-night-market/tree/master/plugins/archetypes\", \"emoji\": \"\\ud83c\\udfd7\\ufe0f\"}}\nsource: claude-night-market\nsource_plugin: archetypes\n---\n\n> **Night Market Skill** — ported from [claude-night-market/archetypes](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes). For the full experience with agents, hooks, and commands, install the Claude Code plugin.\n\n\n# The CQRS and Event Sourcing Paradigm\n\n\n## When To Use\n\n- Designing event-sourced systems with complex domain logic\n- Systems requiring full audit trails of state changes\n\n## When NOT To Use\n\n- Simple CRUD applications without complex domain logic\n- Small projects where event sourcing adds unnecessary complexity\n\n## When to Employ This Paradigm\n- When read and write workloads have vastly different performance characteristics or scaling requirements.\n- When all business events must be captured in a durable, immutable history or audit trail.\n- When a business needs to rebuild projections of data or support temporal queries (e.g., \"What did the state of this entity look like yesterday?\").\n\n## Adoption Steps\n1. **Identify Aggregates**: Following Domain-Driven Design principles, specify the bounded contexts and the business invariants that each command must enforce on an aggregate.\n2. **Model Commands and Events**: Define the schemas and validation rules for all commands and the events they produce. Document a clear strategy for versioning and schema evolution.\n3. **Implement the Write Side (Command Side)**: Command handlers are responsible for loading an aggregate's event stream, executing business logic, and atomically appending new events to the stream.\n4. **Build Projections to the Read Side**: Create separate read models (projections) that are fed by subscriptions to the event stream. Implement back-pressure and retry policies for these subscriptions.\n5. **validate Full Observability**: Implement detailed logging that includes event IDs, sequence numbers, and metrics for tracking the lag time of each projection.\n\n## Key Deliverables\n- An Architecture Decision Record (ADR) detailing the aggregates, the chosen event store technology, the projection strategy, and the expected data consistency model (e.g., eventual consistency SLAs).\n- A suite of tests for command handlers that use in-memory event streams, complemented by integration tests for the projections.\n- Operational tooling for replaying events, taking state snapshots for performance, and managing schema migrations.\n\n## Risks & Mitigations\n- **High Operational Overhead**:\n  - **Mitigation**: Bugs related to event ordering and replays can be difficult to diagnose. Invest heavily in automation, Dead-Letter Queues (DLQs) for failed events, and regular \"chaos engineering\" drills to test resilience.\n- **Challenges of Eventual Consistency**:\n  - **Mitigation**: Users may be confused by delays between performing an action and seeing the result. Clearly document the SLAs for read model updates and manage user-facing expectations accordingly, for example, by providing immediate feedback on the command side.\n- **Schema Drift**:\n  - **Mitigation**: An unplanned change to an event schema can break consumers. Enforce the use of a formal schema registry and implement version gates in the CI/CD pipeline to prevent the emission of unvalidated event versions.\n\n## Concrete Components\n\nThese vocabulary items name the concrete tools and abstractions\nthat show up when the paradigm is implemented. They are not\nrequired dependencies and they are not part of the skill's\n``tools:`` frontmatter (which is reserved for Claude Code tool\nrestrictions). Use this list to disambiguate during architecture\ndiscussions.\n\n- ``event-store`` -- append-only log of domain events; the system of record from which projections are built\n- ``message-broker`` -- carries commands and integration events between bounded contexts\n- ``projection-builder`` -- rebuilds read-side views by replaying the event store\n\nFile v1.9.17:_meta.json\n\n{\n  \"ownerId\": \"kn7d107jg9jv602h9ytsegydq184a42s\",\n  \"slug\": \"nm-archetypes-architecture-paradigm-cqrs-es\",\n  \"version\": \"1.9.17\",\n  \"publishedAt\": 1785389329006\n}\n\nFile v1.9.17:skill-card.md\n\n## Description: <br>\nApplies CQRS and Event Sourcing for read/write separation and audit trails. <br>\n\nThis skill is ready for commercial/non-commercial use. <br>\n\n## Publisher: <br>\n[athola](https://clawhub.ai/user/athola) <br>\n\n### License/Terms of Use: <br>\nMIT-0 <br>\n\n\n## Use Case: <br>\nDevelopers and architects use this skill to decide when CQRS and Event Sourcing fit a system, then outline aggregates, commands, events, projections, observability, and operational deliverables. <br>\n\n### Deployment Geography for Use: <br>\nGlobal <br>\n\n## Known Risks and Mitigations: <br>\nRisk: Broad architecture triggers may cause CQRS/Event Sourcing guidance to appear for simple CRUD or small projects where the pattern is unnecessary. <br>\nMitigation: Confirm the project needs read/write separation, durable event history, temporal queries, or audit trails before applying the pattern. <br>\nRisk: CQRS/Event Sourcing can introduce operational overhead, eventual consistency concerns, and schema drift. <br>\nMitigation: Use explicit event schemas, versioning controls, projection monitoring, replay tooling, and documented read-model consistency expectations. <br>\n\n\n## Reference(s): <br>\n- [ClawHub skill page](https://clawhub.ai/athola/skills/nm-archetypes-architecture-paradigm-cqrs-es) <br>\n- [OpenClaw homepage metadata](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes) <br>\n\n\n## Skill Output: <br>\n**Output Type(s):** [guidance, markdown, configuration] <br>\n**Output Format:** [Markdown architecture guidance with checklists and implementation vocabulary] <br>\n**Output Parameters:** [1D] <br>\n**Other Properties Related to Output:** [Documentation-only advisory output; no tool calls, shell commands, or code execution are defined by the skill.] <br>\n\n## Skill Version(s): <br>\n1.9.17 (source: server release evidence) <br>\n\n## Ethical Considerations: <br>\nUsers should evaluate whether this skill is appropriate for their environment, review any generated or modified files before relying on them, and apply their organization's safety, security, and compliance requirements before deployment. <br>\n\nArchive v1.9.16: 3 files, 3651 bytes\n\nFiles: skill-card.md (2147b), SKILL.md (4364b), _meta.json (163b)\n\nFile v1.9.16:SKILL.md\n\n---\nname: architecture-paradigm-cqrs-es\ndescription: Applies CQRS and Event Sourcing for read/write separation and audit trails\nversion: 1.9.8\ntriggers:\n  - architecture\n  - CQRS\n  - Event-Sourcing\n  - distributed-systems\n  - audit-trail\n  - scalability\n  - designing systems with complex domain logic or full state-change history\nmetadata: {\"openclaw\": {\"homepage\": \"https://github.com/athola/claude-night-market/tree/master/plugins/archetypes\", \"emoji\": \"\\ud83c\\udfd7\\ufe0f\"}}\nsource: claude-night-market\nsource_plugin: archetypes\n---\n\n> **Night Market Skill** — ported from [claude-night-market/archetypes](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes). For the full experience with agents, hooks, and commands, install the Claude Code plugin.\n\n\n# The CQRS and Event Sourcing Paradigm\n\n\n## When To Use\n\n- Designing event-sourced systems with complex domain logic\n- Systems requiring full audit trails of state changes\n\n## When NOT To Use\n\n- Simple CRUD applications without complex domain logic\n- Small projects where event sourcing adds unnecessary complexity\n\n## When to Employ This Paradigm\n- When read and write workloads have vastly different performance characteristics or scaling requirements.\n- When all business events must be captured in a durable, immutable history or audit trail.\n- When a business needs to rebuild projections of data or support temporal queries (e.g., \"What did the state of this entity look like yesterday?\").\n\n## Adoption Steps\n1. **Identify Aggregates**: Following Domain-Driven Design principles, specify the bounded contexts and the business invariants that each command must enforce on an aggregate.\n2. **Model Commands and Events**: Define the schemas and validation rules for all commands and the events they produce. Document a clear strategy for versioning and schema evolution.\n3. **Implement the Write Side (Command Side)**: Command handlers are responsible for loading an aggregate's event stream, executing business logic, and atomically appending new events to the stream.\n4. **Build Projections to the Read Side**: Create separate read models (projections) that are fed by subscriptions to the event stream. Implement back-pressure and retry policies for these subscriptions.\n5. **validate Full Observability**: Implement detailed logging that includes event IDs, sequence numbers, and metrics for tracking the lag time of each projection.\n\n## Key Deliverables\n- An Architecture Decision Record (ADR) detailing the aggregates, the chosen event store technology, the projection strategy, and the expected data consistency model (e.g., eventual consistency SLAs).\n- A suite of tests for command handlers that use in-memory event streams, complemented by integration tests for the projections.\n- Operational tooling for replaying events, taking state snapshots for performance, and managing schema migrations.\n\n## Risks & Mitigations\n- **High Operational Overhead**:\n  - **Mitigation**: Bugs related to event ordering and replays can be difficult to diagnose. Invest heavily in automation, Dead-Letter Queues (DLQs) for failed events, and regular \"chaos engineering\" drills to test resilience.\n- **Challenges of Eventual Consistency**:\n  - **Mitigation**: Users may be confused by delays between performing an action and seeing the result. Clearly document the SLAs for read model updates and manage user-facing expectations accordingly, for example, by providing immediate feedback on the command side.\n- **Schema Drift**:\n  - **Mitigation**: An unplanned change to an event schema can break consumers. Enforce the use of a formal schema registry and implement version gates in the CI/CD pipeline to prevent the emission of unvalidated event versions.\n\n## Concrete Components\n\nThese vocabulary items name the concrete tools and abstractions\nthat show up when the paradigm is implemented. They are not\nrequired dependencies and they are not part of the skill's\n``tools:`` frontmatter (which is reserved for Claude Code tool\nrestrictions). Use this list to disambiguate during architecture\ndiscussions.\n\n- ``event-store`` -- append-only log of domain events; the system of record from which projections are built\n- ``message-broker`` -- carries commands and integration events between bounded contexts\n- ``projection-builder`` -- rebuilds read-side views by replaying the event store\n\nFile v1.9.16:_meta.json\n\n{\n  \"ownerId\": \"kn7d107jg9jv602h9ytsegydq184a42s\",\n  \"slug\": \"nm-archetypes-architecture-paradigm-cqrs-es\",\n  \"version\": \"1.9.16\",\n  \"publishedAt\": 1784058357363\n}\n\nFile v1.9.16:skill-card.md\n\n## Description: <br>\nApplies CQRS and Event Sourcing for read/write separation and audit trails. <br>\n\nThis skill is ready for commercial/non-commercial use. <br>\n\n## Publisher: <br>\n[athola](https://clawhub.ai/user/athola) <br>\n\n### License/Terms of Use: <br>\nMIT-0 <br>\n\n\n## Use Case: <br>\nDevelopers and architects use this skill to evaluate and apply CQRS and Event Sourcing when systems need separated read/write models, complex domain behavior, durable event history, or audit trails. <br>\n\n### Deployment Geography for Use: <br>\nGlobal <br>\n\n## Known Risks and Mitigations: <br>\nRisk: The skill may appear in broad architecture or scalability discussions where CQRS and Event Sourcing are not actually warranted. <br>\nMitigation: Use it only when the system needs complex domain logic, separate read/write scaling, or full state-change history; avoid it for simple CRUD applications. <br>\nRisk: CQRS and Event Sourcing can add operational overhead, eventual consistency, and event schema drift risks. <br>\nMitigation: Plan observability, replay and recovery tooling, read-model update expectations, schema versioning, and validation gates before adopting the paradigm. <br>\n\n\n## Reference(s): <br>\n- [ClawHub skill page](https://clawhub.ai/athola/skills/nm-archetypes-architecture-paradigm-cqrs-es) <br>\n- [OpenClaw homepage metadata](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes) <br>\n\n\n## Skill Output: <br>\n**Output Type(s):** [guidance, markdown, configuration] <br>\n**Output Format:** [Markdown guidance with architecture steps, deliverables, risks, and component vocabulary] <br>\n**Output Parameters:** [1D] <br>\n**Other Properties Related to Output:** [Text-only architecture guidance; no tools, credentials, or privileged actions are requested.] <br>\n\n## Skill Version(s): <br>\n1.9.16 (source: server release evidence) <br>\n\n## Ethical Considerations: <br>\nUsers should evaluate whether this skill is appropriate for their environment, review any generated or modified files before relying on them, and apply their organization's safety, security, and compliance requirements before deployment. <br>\n\nArchive v1.9.15: 3 files, 3822 bytes\n\nFiles: skill-card.md (2582b), SKILL.md (4364b), _meta.json (163b)\n\nFile v1.9.15:SKILL.md\n\n---\nname: architecture-paradigm-cqrs-es\ndescription: Applies CQRS and Event Sourcing for read/write separation and audit trails\nversion: 1.9.8\ntriggers:\n  - architecture\n  - CQRS\n  - Event-Sourcing\n  - distributed-systems\n  - audit-trail\n  - scalability\n  - designing systems with complex domain logic or full state-change history\nmetadata: {\"openclaw\": {\"homepage\": \"https://github.com/athola/claude-night-market/tree/master/plugins/archetypes\", \"emoji\": \"\\ud83c\\udfd7\\ufe0f\"}}\nsource: claude-night-market\nsource_plugin: archetypes\n---\n\n> **Night Market Skill** — ported from [claude-night-market/archetypes](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes). For the full experience with agents, hooks, and commands, install the Claude Code plugin.\n\n\n# The CQRS and Event Sourcing Paradigm\n\n\n## When To Use\n\n- Designing event-sourced systems with complex domain logic\n- Systems requiring full audit trails of state changes\n\n## When NOT To Use\n\n- Simple CRUD applications without complex domain logic\n- Small projects where event sourcing adds unnecessary complexity\n\n## When to Employ This Paradigm\n- When read and write workloads have vastly different performance characteristics or scaling requirements.\n- When all business events must be captured in a durable, immutable history or audit trail.\n- When a business needs to rebuild projections of data or support temporal queries (e.g., \"What did the state of this entity look like yesterday?\").\n\n## Adoption Steps\n1. **Identify Aggregates**: Following Domain-Driven Design principles, specify the bounded contexts and the business invariants that each command must enforce on an aggregate.\n2. **Model Commands and Events**: Define the schemas and validation rules for all commands and the events they produce. Document a clear strategy for versioning and schema evolution.\n3. **Implement the Write Side (Command Side)**: Command handlers are responsible for loading an aggregate's event stream, executing business logic, and atomically appending new events to the stream.\n4. **Build Projections to the Read Side**: Create separate read models (projections) that are fed by subscriptions to the event stream. Implement back-pressure and retry policies for these subscriptions.\n5. **validate Full Observability**: Implement detailed logging that includes event IDs, sequence numbers, and metrics for tracking the lag time of each projection.\n\n## Key Deliverables\n- An Architecture Decision Record (ADR) detailing the aggregates, the chosen event store technology, the projection strategy, and the expected data consistency model (e.g., eventual consistency SLAs).\n- A suite of tests for command handlers that use in-memory event streams, complemented by integration tests for the projections.\n- Operational tooling for replaying events, taking state snapshots for performance, and managing schema migrations.\n\n## Risks & Mitigations\n- **High Operational Overhead**:\n  - **Mitigation**: Bugs related to event ordering and replays can be difficult to diagnose. Invest heavily in automation, Dead-Letter Queues (DLQs) for failed events, and regular \"chaos engineering\" drills to test resilience.\n- **Challenges of Eventual Consistency**:\n  - **Mitigation**: Users may be confused by delays between performing an action and seeing the result. Clearly document the SLAs for read model updates and manage user-facing expectations accordingly, for example, by providing immediate feedback on the command side.\n- **Schema Drift**:\n  - **Mitigation**: An unplanned change to an event schema can break consumers. Enforce the use of a formal schema registry and implement version gates in the CI/CD pipeline to prevent the emission of unvalidated event versions.\n\n## Concrete Components\n\nThese vocabulary items name the concrete tools and abstractions\nthat show up when the paradigm is implemented. They are not\nrequired dependencies and they are not part of the skill's\n``tools:`` frontmatter (which is reserved for Claude Code tool\nrestrictions). Use this list to disambiguate during architecture\ndiscussions.\n\n- ``event-store`` -- append-only log of domain events; the system of record from which projections are built\n- ``message-broker`` -- carries commands and integration events between bounded contexts\n- ``projection-builder`` -- rebuilds read-side views by replaying the event store\n\nFile v1.9.15:_meta.json\n\n{\n  \"ownerId\": \"kn7d107jg9jv602h9ytsegydq184a42s\",\n  \"slug\": \"nm-archetypes-architecture-paradigm-cqrs-es\",\n  \"version\": \"1.9.15\",\n  \"publishedAt\": 1783200008814\n}\n\nFile v1.9.15:skill-card.md\n\n## Description: <br>\nApplies CQRS and Event Sourcing for read/write separation and audit trails. <br>\n\nThis skill is ready for commercial/non-commercial use. <br>\n\n## Publisher: <br>\n[athola](https://clawhub.ai/user/athola) <br>\n\n### License/Terms of Use: <br>\nMIT-0 <br>\n\n\n## Use Case: <br>\nDevelopers and software architects use this skill to decide when CQRS and Event Sourcing fit systems with complex domain logic, separated read/write workloads, temporal queries, or full audit-trail requirements. It guides adoption planning, key deliverables, operational concerns, and vocabulary for event-sourced architecture discussions. <br>\n\n### Deployment Geography for Use: <br>\nGlobal <br>\n\n## Known Risks and Mitigations: <br>\nRisk: CQRS and Event Sourcing guidance can be over-applied to simple CRUD systems or small projects where the pattern adds unnecessary complexity. <br>\nMitigation: Confirm the system has complex domain logic, distinct read/write scaling needs, temporal query requirements, or audit-trail obligations before adopting the pattern. <br>\nRisk: Event-sourced systems can create operational issues around event ordering, replays, projection lag, and schema drift. <br>\nMitigation: Use schema governance, projection observability, retry and dead-letter handling, replay tooling, and documented consistency expectations. <br>\nRisk: The artifact mentions a separate Claude Code plugin that is not part of this submitted artifact. <br>\nMitigation: Review and scan the separate plugin independently before installing or using it. <br>\n\n\n## Reference(s): <br>\n- [Claude Night Market archetypes](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes) <br>\n- [ClawHub skill page](https://clawhub.ai/athola/skills/nm-archetypes-architecture-paradigm-cqrs-es) <br>\n\n\n## Skill Output: <br>\n**Output Type(s):** [text, markdown, guidance, configuration] <br>\n**Output Format:** [Markdown guidance with architecture recommendations and structured lists] <br>\n**Output Parameters:** [1D] <br>\n**Other Properties Related to Output:** [Produces ADR, testing, operational tooling, and terminology guidance; no executable code is included in the submitted artifact.] <br>\n\n## Skill Version(s): <br>\n1.9.15 (source: server release metadata; artifact frontmatter reports 1.9.8) <br>\n\n## Ethical Considerations: <br>\nUsers should evaluate whether this skill is appropriate for their environment, review any generated or modified files before relying on them, and apply their organization's safety, security, and compliance requirements before deployment. <br>\n\nArchive v1.9.14: 3 files, 3674 bytes\n\nFiles: skill-card.md (2256b), SKILL.md (4364b), _meta.json (163b)\n\nFile v1.9.14:SKILL.md\n\n---\nname: architecture-paradigm-cqrs-es\ndescription: Applies CQRS and Event Sourcing for read/write separation and audit trails\nversion: 1.9.8\ntriggers:\n  - architecture\n  - CQRS\n  - Event-Sourcing\n  - distributed-systems\n  - audit-trail\n  - scalability\n  - designing systems with complex domain logic or full state-change history\nmetadata: {\"openclaw\": {\"homepage\": \"https://github.com/athola/claude-night-market/tree/master/plugins/archetypes\", \"emoji\": \"\\ud83c\\udfd7\\ufe0f\"}}\nsource: claude-night-market\nsource_plugin: archetypes\n---\n\n> **Night Market Skill** — ported from [claude-night-market/archetypes](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes). For the full experience with agents, hooks, and commands, install the Claude Code plugin.\n\n\n# The CQRS and Event Sourcing Paradigm\n\n\n## When To Use\n\n- Designing event-sourced systems with complex domain logic\n- Systems requiring full audit trails of state changes\n\n## When NOT To Use\n\n- Simple CRUD applications without complex domain logic\n- Small projects where event sourcing adds unnecessary complexity\n\n## When to Employ This Paradigm\n- When read and write workloads have vastly different performance characteristics or scaling requirements.\n- When all business events must be captured in a durable, immutable history or audit trail.\n- When a business needs to rebuild projections of data or support temporal queries (e.g., \"What did the state of this entity look like yesterday?\").\n\n## Adoption Steps\n1. **Identify Aggregates**: Following Domain-Driven Design principles, specify the bounded contexts and the business invariants that each command must enforce on an aggregate.\n2. **Model Commands and Events**: Define the schemas and validation rules for all commands and the events they produce. Document a clear strategy for versioning and schema evolution.\n3. **Implement the Write Side (Command Side)**: Command handlers are responsible for loading an aggregate's event stream, executing business logic, and atomically appending new events to the stream.\n4. **Build Projections to the Read Side**: Create separate read models (projections) that are fed by subscriptions to the event stream. Implement back-pressure and retry policies for these subscriptions.\n5. **validate Full Observability**: Implement detailed logging that includes event IDs, sequence numbers, and metrics for tracking the lag time of each projection.\n\n## Key Deliverables\n- An Architecture Decision Record (ADR) detailing the aggregates, the chosen event store technology, the projection strategy, and the expected data consistency model (e.g., eventual consistency SLAs).\n- A suite of tests for command handlers that use in-memory event streams, complemented by integration tests for the projections.\n- Operational tooling for replaying events, taking state snapshots for performance, and managing schema migrations.\n\n## Risks & Mitigations\n- **High Operational Overhead**:\n  - **Mitigation**: Bugs related to event ordering and replays can be difficult to diagnose. Invest heavily in automation, Dead-Letter Queues (DLQs) for failed events, and regular \"chaos engineering\" drills to test resilience.\n- **Challenges of Eventual Consistency**:\n  - **Mitigation**: Users may be confused by delays between performing an action and seeing the result. Clearly document the SLAs for read model updates and manage user-facing expectations accordingly, for example, by providing immediate feedback on the command side.\n- **Schema Drift**:\n  - **Mitigation**: An unplanned change to an event schema can break consumers. Enforce the use of a formal schema registry and implement version gates in the CI/CD pipeline to prevent the emission of unvalidated event versions.\n\n## Concrete Components\n\nThese vocabulary items name the concrete tools and abstractions\nthat show up when the paradigm is implemented. They are not\nrequired dependencies and they are not part of the skill's\n``tools:`` frontmatter (which is reserved for Claude Code tool\nrestrictions). Use this list to disambiguate during architecture\ndiscussions.\n\n- ``event-store`` -- append-only log of domain events; the system of record from which projections are built\n- ``message-broker`` -- carries commands and integration events between bounded contexts\n- ``projection-builder`` -- rebuilds read-side views by replaying the event store\n\nFile v1.9.14:_meta.json\n\n{\n  \"ownerId\": \"kn7d107jg9jv602h9ytsegydq184a42s\",\n  \"slug\": \"nm-archetypes-architecture-paradigm-cqrs-es\",\n  \"version\": \"1.9.14\",\n  \"publishedAt\": 1782841843018\n}\n\nFile v1.9.14:skill-card.md\n\n## Description: <br>\nApplies CQRS and Event Sourcing for read/write separation and audit trails. <br>\n\nThis skill is ready for commercial/non-commercial use. <br>\n\n## Publisher: <br>\n[athola](https://clawhub.ai/user/athola) <br>\n\n### License/Terms of Use: <br>\nMIT-0 <br>\n\n\n## Use Case: <br>\nDevelopers and architects use this skill to decide when CQRS and Event Sourcing fit a system, then plan aggregates, commands, events, projections, audit trails, and operational safeguards. <br>\n\n### Deployment Geography for Use: <br>\nGlobal <br>\n\n## Known Risks and Mitigations: <br>\nRisk: The skill may activate broadly on architecture discussions because its trigger terms include general architecture and distributed-systems language. <br>\nMitigation: Review and narrow activation triggers before installation if the agent should only invoke it for CQRS or Event Sourcing work. <br>\nRisk: CQRS and Event Sourcing guidance can add operational complexity, eventual consistency, and event schema management obligations to a system. <br>\nMitigation: Apply the skill's guidance only after review by architecture owners, and require explicit plans for projection lag, replay handling, schema versioning, observability, and failure recovery. <br>\n\n\n## Reference(s): <br>\n- [ClawHub skill page](https://clawhub.ai/athola/skills/nm-archetypes-architecture-paradigm-cqrs-es) <br>\n- [OpenClaw homepage](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes) <br>\n\n\n## Skill Output: <br>\n**Output Type(s):** [guidance, markdown, code, configuration] <br>\n**Output Format:** [Markdown guidance with architecture recommendations, implementation steps, deliverables, and risk mitigations] <br>\n**Output Parameters:** [1D] <br>\n**Other Properties Related to Output:** [May include ADR content, command and event schema guidance, projection design notes, testing guidance, and operational practices.] <br>\n\n## Skill Version(s): <br>\n1.9.14 (source: server release evidence) <br>\n\n## Ethical Considerations: <br>\nUsers should evaluate whether this skill is appropriate for their environment, review any generated or modified files before relying on them, and apply their organization's safety, security, and compliance requirements before deployment. <br>\n\nArchive v1.9.13: 3 files, 3751 bytes\n\nFiles: skill-card.md (2385b), SKILL.md (4364b), _meta.json (163b)\n\nFile v1.9.13:SKILL.md\n\n---\nname: architecture-paradigm-cqrs-es\ndescription: Applies CQRS and Event Sourcing for read/write separation and audit trails\nversion: 1.9.8\ntriggers:\n  - architecture\n  - CQRS\n  - Event-Sourcing\n  - distributed-systems\n  - audit-trail\n  - scalability\n  - designing systems with complex domain logic or full state-change history\nmetadata: {\"openclaw\": {\"homepage\": \"https://github.com/athola/claude-night-market/tree/master/plugins/archetypes\", \"emoji\": \"\\ud83c\\udfd7\\ufe0f\"}}\nsource: claude-night-market\nsource_plugin: archetypes\n---\n\n> **Night Market Skill** — ported from [claude-night-market/archetypes](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes). For the full experience with agents, hooks, and commands, install the Claude Code plugin.\n\n\n# The CQRS and Event Sourcing Paradigm\n\n\n## When To Use\n\n- Designing event-sourced systems with complex domain logic\n- Systems requiring full audit trails of state changes\n\n## When NOT To Use\n\n- Simple CRUD applications without complex domain logic\n- Small projects where event sourcing adds unnecessary complexity\n\n## When to Employ This Paradigm\n- When read and write workloads have vastly different performance characteristics or scaling requirements.\n- When all business events must be captured in a durable, immutable history or audit trail.\n- When a business needs to rebuild projections of data or support temporal queries (e.g., \"What did the state of this entity look like yesterday?\").\n\n## Adoption Steps\n1. **Identify Aggregates**: Following Domain-Driven Design principles, specify the bounded contexts and the business invariants that each command must enforce on an aggregate.\n2. **Model Commands and Events**: Define the schemas and validation rules for all commands and the events they produce. Document a clear strategy for versioning and schema evolution.\n3. **Implement the Write Side (Command Side)**: Command handlers are responsible for loading an aggregate's event stream, executing business logic, and atomically appending new events to the stream.\n4. **Build Projections to the Read Side**: Create separate read models (projections) that are fed by subscriptions to the event stream. Implement back-pressure and retry policies for these subscriptions.\n5. **validate Full Observability**: Implement detailed logging that includes event IDs, sequence numbers, and metrics for tracking the lag time of each projection.\n\n## Key Deliverables\n- An Architecture Decision Record (ADR) detailing the aggregates, the chosen event store technology, the projection strategy, and the expected data consistency model (e.g., eventual consistency SLAs).\n- A suite of tests for command handlers that use in-memory event streams, complemented by integration tests for the projections.\n- Operational tooling for replaying events, taking state snapshots for performance, and managing schema migrations.\n\n## Risks & Mitigations\n- **High Operational Overhead**:\n  - **Mitigation**: Bugs related to event ordering and replays can be difficult to diagnose. Invest heavily in automation, Dead-Letter Queues (DLQs) for failed events, and regular \"chaos engineering\" drills to test resilience.\n- **Challenges of Eventual Consistency**:\n  - **Mitigation**: Users may be confused by delays between performing an action and seeing the result. Clearly document the SLAs for read model updates and manage user-facing expectations accordingly, for example, by providing immediate feedback on the command side.\n- **Schema Drift**:\n  - **Mitigation**: An unplanned change to an event schema can break consumers. Enforce the use of a formal schema registry and implement version gates in the CI/CD pipeline to prevent the emission of unvalidated event versions.\n\n## Concrete Components\n\nThese vocabulary items name the concrete tools and abstractions\nthat show up when the paradigm is implemented. They are not\nrequired dependencies and they are not part of the skill's\n``tools:`` frontmatter (which is reserved for Claude Code tool\nrestrictions). Use this list to disambiguate during architecture\ndiscussions.\n\n- ``event-store`` -- append-only log of domain events; the system of record from which projections are built\n- ``message-broker`` -- carries commands and integration events between bounded contexts\n- ``projection-builder`` -- rebuilds read-side views by replaying the event store\n\nFile v1.9.13:_meta.json\n\n{\n  \"ownerId\": \"kn7d107jg9jv602h9ytsegydq184a42s\",\n  \"slug\": \"nm-archetypes-architecture-paradigm-cqrs-es\",\n  \"version\": \"1.9.13\",\n  \"publishedAt\": 1782576914759\n}\n\nFile v1.9.13:skill-card.md\n\n## Description: <br>\nApplies CQRS and Event Sourcing for read/write separation and audit trails. <br>\n\nThis skill is ready for commercial/non-commercial use. <br>\n\n## Publisher: <br>\n[athola](https://clawhub.ai/user/athola) <br>\n\n### License/Terms of Use: <br>\nMIT-0 <br>\n\n\n## Use Case: <br>\nDevelopers and architects use this skill to decide when CQRS and Event Sourcing fit systems with complex domain logic, separate read/write workloads, durable audit trails, projections, and event replay needs. <br>\n\n### Deployment Geography for Use: <br>\nGlobal <br>\n\n## Known Risks and Mitigations: <br>\nRisk: CQRS and Event Sourcing can add operational complexity when applied to simple CRUD or small systems. <br>\nMitigation: Use the skill's fit criteria before adoption and avoid these patterns when the system does not need complex domain logic, separate scaling, or a full audit trail. <br>\nRisk: Eventual consistency can make user-visible state lag behind accepted commands. <br>\nMitigation: Define read-model update expectations and provide immediate command-side feedback where user experience depends on timely confirmation. <br>\nRisk: Event schema changes can break projections or consumers. <br>\nMitigation: Document schema versioning, use validation gates, and plan migration or replay tooling before production use. <br>\n\n\n## Reference(s): <br>\n- [ClawHub skill page](https://clawhub.ai/athola/skills/nm-archetypes-architecture-paradigm-cqrs-es) <br>\n- [Publisher profile](https://clawhub.ai/user/athola) <br>\n- [OpenClaw homepage metadata](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes) <br>\n\n\n## Skill Output: <br>\n**Output Type(s):** [guidance, markdown, configuration] <br>\n**Output Format:** [Markdown architecture guidance with adoption steps, deliverables, component vocabulary, and risk notes] <br>\n**Output Parameters:** [1D] <br>\n**Other Properties Related to Output:** [Documentation-only; no tools, credentials, API keys, or actions are requested.] <br>\n\n## Skill Version(s): <br>\n1.9.13 (source: server release evidence; artifact frontmatter lists 1.9.8) <br>\n\n## Ethical Considerations: <br>\nUsers should evaluate whether this skill is appropriate for their environment, review any generated or modified files before relying on them, and apply their organization's safety, security, and compliance requirements before deployment. <br>\n\nArchive v1.9.12: 3 files, 3500 bytes\n\nFiles: skill-card.md (1795b), SKILL.md (4364b), _meta.json (163b)\n\nFile v1.9.12:SKILL.md\n\n---\nname: architecture-paradigm-cqrs-es\ndescription: Applies CQRS and Event Sourcing for read/write separation and audit trails\nversion: 1.9.8\ntriggers:\n  - architecture\n  - CQRS\n  - Event-Sourcing\n  - distributed-systems\n  - audit-trail\n  - scalability\n  - designing systems with complex domain logic or full state-change history\nmetadata: {\"openclaw\": {\"homepage\": \"https://github.com/athola/claude-night-market/tree/master/plugins/archetypes\", \"emoji\": \"\\ud83c\\udfd7\\ufe0f\"}}\nsource: claude-night-market\nsource_plugin: archetypes\n---\n\n> **Night Market Skill** — ported from [claude-night-market/archetypes](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes). For the full experience with agents, hooks, and commands, install the Claude Code plugin.\n\n\n# The CQRS and Event Sourcing Paradigm\n\n\n## When To Use\n\n- Designing event-sourced systems with complex domain logic\n- Systems requiring full audit trails of state changes\n\n## When NOT To Use\n\n- Simple CRUD applications without complex domain logic\n- Small projects where event sourcing adds unnecessary complexity\n\n## When to Employ This Paradigm\n- When read and write workloads have vastly different performance characteristics or scaling requirements.\n- When all business events must be captured in a durable, immutable history or audit trail.\n- When a business needs to rebuild projections of data or support temporal queries (e.g., \"What did the state of this entity look like yesterday?\").\n\n## Adoption Steps\n1. **Identify Aggregates**: Following Domain-Driven Design principles, specify the bounded contexts and the business invariants that each command must enforce on an aggregate.\n2. **Model Commands and Events**: Define the schemas and validation rules for all commands and the events they produce. Document a clear strategy for versioning and schema evolution.\n3. **Implement the Write Side (Command Side)**: Command handlers are responsible for loading an aggregate's event stream, executing business logic, and atomically appending new events to the stream.\n4. **Build Projections to the Read Side**: Create separate read models (projections) that are fed by subscriptions to the event stream. Implement back-pressure and retry policies for these subscriptions.\n5. **validate Full Observability**: Implement detailed logging that includes event IDs, sequence numbers, and metrics for tracking the lag time of each projection.\n\n## Key Deliverables\n- An Architecture Decision Record (ADR) detailing the aggregates, the chosen event store technology, the projection strategy, and the expected data consistency model (e.g., eventual consistency SLAs).\n- A suite of tests for command handlers that use in-memory event streams, complemented by integration tests for the projections.\n- Operational tooling for replaying events, taking state snapshots for performance, and managing schema migrations.\n\n## Risks & Mitigations\n- **High Operational Overhead**:\n  - **Mitigation**: Bugs related to event ordering and replays can be difficult to diagnose. Invest heavily in automation, Dead-Letter Queues (DLQs) for failed events, and regular \"chaos engineering\" drills to test resilience.\n- **Challenges of Eventual Consistency**:\n  - **Mitigation**: Users may be confused by delays between performing an action and seeing the result. Clearly document the SLAs for read model updates and manage user-facing expectations accordingly, for example, by providing immediate feedback on the command side.\n- **Schema Drift**:\n  - **Mitigation**: An unplanned change to an event schema can break consumers. Enforce the use of a formal schema registry and implement version gates in the CI/CD pipeline to prevent the emission of unvalidated event versions.\n\n## Concrete Components\n\nThese vocabulary items name the concrete tools and abstractions\nthat show up when the paradigm is implemented. They are not\nrequired dependencies and they are not part of the skill's\n``tools:`` frontmatter (which is reserved for Claude Code tool\nrestrictions). Use this list to disambiguate during architecture\ndiscussions.\n\n- ``event-store`` -- append-only log of domain events; the system of record from which projections are built\n- ``message-broker`` -- carries commands and integration events between bounded contexts\n- ``projection-builder`` -- rebuilds read-side views by replaying the event store\n\nFile v1.9.12:_meta.json\n\n{\n  \"ownerId\": \"kn7d107jg9jv602h9ytsegydq184a42s\",\n  \"slug\": \"nm-archetypes-architecture-paradigm-cqrs-es\",\n  \"version\": \"1.9.12\",\n  \"publishedAt\": 1781838513321\n}\n\nFile v1.9.12:skill-card.md\n\n## Description: <br>\nApplies CQRS and Event Sourcing for read/write separation and audit trails. <br>\n\nThis skill is ready for commercial/non-commercial use. <br>\n\n## Publisher: <br>\n[athola](https://clawhub.ai/user/athola) <br>\n\n### License/Terms of Use: <br>\nMIT-0 <br>\n\n\n## Use Case: <br>\nDevelopers and architecture teams use this skill to evaluate CQRS and Event Sourcing for systems that need separate read/write models, durable event history, audit trails, and projection rebuilds. <br>\n\n### Deployment Geography for Use: <br>\nGlobal <br>\n\n## Known Risks and Mitigations: <br>\nRisk: The skill may activate in broad architecture or scalability conversations where CQRS and Event Sourcing are not a good fit. <br>\nMitigation: Check the problem against the skill's stated when-to-use and when-not-to-use criteria before applying its recommendations. <br>\n\n\n## Reference(s): <br>\n- [ClawHub skill page](https://clawhub.ai/athola/nm-archetypes-architecture-paradigm-cqrs-es) <br>\n- [OpenClaw homepage metadata](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes) <br>\n\n\n## Skill Output: <br>\n**Output Type(s):** [guidance, markdown] <br>\n**Output Format:** [Markdown architecture guidance] <br>\n**Output Parameters:** [1D] <br>\n**Other Properties Related to Output:** [Documentation-only guidance; no API calls, shell commands, credential handling, or tool use were reported.] <br>\n\n## Skill Version(s): <br>\n1.9.12 (source: server release evidence; artifact frontmatter reports 1.9.8) <br>\n\n## Ethical Considerations: <br>\nUsers should evaluate whether this skill is appropriate for their environment, review any generated or modified files before relying on them, and apply their organization's safety, security, and compliance requirements before deployment. <br>\n\nArchive v1.8.6: 3 files, 3564 bytes\n\nFiles: skill-card.md (1998b), SKILL.md (4364b), _meta.json (162b)\n\nFile v1.8.6:SKILL.md\n\n---\nname: architecture-paradigm-cqrs-es\ndescription: Applies CQRS and Event Sourcing for read/write separation and audit trails\nversion: 1.9.8\ntriggers:\n  - architecture\n  - CQRS\n  - Event-Sourcing\n  - distributed-systems\n  - audit-trail\n  - scalability\n  - designing systems with complex domain logic or full state-change history\nmetadata: {\"openclaw\": {\"homepage\": \"https://github.com/athola/claude-night-market/tree/master/plugins/archetypes\", \"emoji\": \"\\ud83c\\udfd7\\ufe0f\"}}\nsource: claude-night-market\nsource_plugin: archetypes\n---\n\n> **Night Market Skill** — ported from [claude-night-market/archetypes](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes). For the full experience with agents, hooks, and commands, install the Claude Code plugin.\n\n\n# The CQRS and Event Sourcing Paradigm\n\n\n## When To Use\n\n- Designing event-sourced systems with complex domain logic\n- Systems requiring full audit trails of state changes\n\n## When NOT To Use\n\n- Simple CRUD applications without complex domain logic\n- Small projects where event sourcing adds unnecessary complexity\n\n## When to Employ This Paradigm\n- When read and write workloads have vastly different performance characteristics or scaling requirements.\n- When all business events must be captured in a durable, immutable history or audit trail.\n- When a business needs to rebuild projections of data or support temporal queries (e.g., \"What did the state of this entity look like yesterday?\").\n\n## Adoption Steps\n1. **Identify Aggregates**: Following Domain-Driven Design principles, specify the bounded contexts and the business invariants that each command must enforce on an aggregate.\n2. **Model Commands and Events**: Define the schemas and validation rules for all commands and the events they produce. Document a clear strategy for versioning and schema evolution.\n3. **Implement the Write Side (Command Side)**: Command handlers are responsible for loading an aggregate's event stream, executing business logic, and atomically appending new events to the stream.\n4. **Build Projections to the Read Side**: Create separate read models (projections) that are fed by subscriptions to the event stream. Implement back-pressure and retry policies for these subscriptions.\n5. **validate Full Observability**: Implement detailed logging that includes event IDs, sequence numbers, and metrics for tracking the lag time of each projection.\n\n## Key Deliverables\n- An Architecture Decision Record (ADR) detailing the aggregates, the chosen event store technology, the projection strategy, and the expected data consistency model (e.g., eventual consistency SLAs).\n- A suite of tests for command handlers that use in-memory event streams, complemented by integration tests for the projections.\n- Operational tooling for replaying events, taking state snapshots for performance, and managing schema migrations.\n\n## Risks & Mitigations\n- **High Operational Overhead**:\n  - **Mitigation**: Bugs related to event ordering and replays can be difficult to diagnose. Invest heavily in automation, Dead-Letter Queues (DLQs) for failed events, and regular \"chaos engineering\" drills to test resilience.\n- **Challenges of Eventual Consistency**:\n  - **Mitigation**: Users may be confused by delays between performing an action and seeing the result. Clearly document the SLAs for read model updates and manage user-facing expectations accordingly, for example, by providing immediate feedback on the command side.\n- **Schema Drift**:\n  - **Mitigation**: An unplanned change to an event schema can break consumers. Enforce the use of a formal schema registry and implement version gates in the CI/CD pipeline to prevent the emission of unvalidated event versions.\n\n## Concrete Components\n\nThese vocabulary items name the concrete tools and abstractions\nthat show up when the paradigm is implemented. They are not\nrequired dependencies and they are not part of the skill's\n``tools:`` frontmatter (which is reserved for Claude Code tool\nrestrictions). Use this list to disambiguate during architecture\ndiscussions.\n\n- ``event-store`` -- append-only log of domain events; the system of record from which projections are built\n- ``message-broker`` -- carries commands and integration events between bounded contexts\n- ``projection-builder`` -- rebuilds read-side views by replaying the event store\n\nFile v1.8.6:_meta.json\n\n{\n  \"ownerId\": \"kn7d107jg9jv602h9ytsegydq184a42s\",\n  \"slug\": \"nm-archetypes-architecture-paradigm-cqrs-es\",\n  \"version\": \"1.8.6\",\n  \"publishedAt\": 1780867354080\n}\n\nFile v1.8.6:skill-card.md\n\n## Description: <br>\nApplies CQRS and Event Sourcing for read/write separation and audit trails. <br>\n\nThis skill is ready for commercial/non-commercial use. <br>\n\n## Publisher: <br>\n[athola](https://clawhub.ai/user/athola) <br>\n\n### License/Terms of Use: <br>\nMIT-0 <br>\n\n\n## Use Case: <br>\nDevelopers and software architects use this skill to decide when CQRS and Event Sourcing fit systems with complex domain logic, separate read/write scaling needs, or durable audit-history requirements. <br>\n\n### Deployment Geography for Use: <br>\nGlobal <br>\n\n## Known Risks and Mitigations: <br>\nRisk: The guidance may encourage CQRS and Event Sourcing where the added operational complexity is not justified. <br>\nMitigation: Apply it only to systems that need complex domain modeling, separate read/write scaling, durable audit history, or temporal reconstruction. <br>\nRisk: The artifact mentions a separate Claude Code plugin with agents, hooks, and commands that is outside this skill artifact. <br>\nMitigation: Review and scan that plugin separately before installing it. <br>\n\n\n## Reference(s): <br>\n- [ClawHub skill page](https://clawhub.ai/athola/nm-archetypes-architecture-paradigm-cqrs-es) <br>\n- [Project homepage](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes) <br>\n\n\n## Skill Output: <br>\n**Output Type(s):** [Guidance, Markdown, Text] <br>\n**Output Format:** [Markdown architecture guidance] <br>\n**Output Parameters:** [1D] <br>\n**Other Properties Related to Output:** [Documentation-only guidance; no executable code or credential handling is included in the artifact.] <br>\n\n## Skill Version(s): <br>\n1.8.6 (source: server release metadata; artifact frontmatter lists 1.9.8) <br>\n\n## Ethical Considerations: <br>\nUsers should evaluate whether this skill is appropriate for their environment, review any generated or modified files before relying on them, and apply their organization's safety, security, and compliance requirements before deployment. <br>\n\nArchive v1.8.5: 3 files, 3504 bytes\n\nFiles: skill-card.md (2170b), SKILL.md (3947b), _meta.json (162b)\n\nFile v1.8.5:SKILL.md\n\n---\nname: architecture-paradigm-cqrs-es\ndescription: Apply CQRS and Event Sourcing for read/write separation and audit trails\nversion: 1.9.5\ntriggers:\n  - architecture\n  - CQRS\n  - Event-Sourcing\n  - distributed-systems\n  - audit-trail\n  - scalability\n  - auditability is critical\nmetadata: {\"openclaw\": {\"homepage\": \"https://github.com/athola/claude-night-market/tree/master/plugins/archetypes\", \"emoji\": \"\\ud83c\\udfd7\\ufe0f\"}}\nsource: claude-night-market\nsource_plugin: archetypes\n---\n\n> **Night Market Skill** — ported from [claude-night-market/archetypes](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes). For the full experience with agents, hooks, and commands, install the Claude Code plugin.\n\n\n# The CQRS and Event Sourcing Paradigm\n\n\n## When To Use\n\n- Designing event-sourced systems with complex domain logic\n- Systems requiring full audit trails of state changes\n\n## When NOT To Use\n\n- Simple CRUD applications without complex domain logic\n- Small projects where event sourcing adds unnecessary complexity\n\n## When to Employ This Paradigm\n- When read and write workloads have vastly different performance characteristics or scaling requirements.\n- When all business events must be captured in a durable, immutable history or audit trail.\n- When a business needs to rebuild projections of data or support temporal queries (e.g., \"What did the state of this entity look like yesterday?\").\n\n## Adoption Steps\n1. **Identify Aggregates**: Following Domain-Driven Design principles, specify the bounded contexts and the business invariants that each command must enforce on an aggregate.\n2. **Model Commands and Events**: Define the schemas and validation rules for all commands and the events they produce. Document a clear strategy for versioning and schema evolution.\n3. **Implement the Write Side (Command Side)**: Command handlers are responsible for loading an aggregate's event stream, executing business logic, and atomically appending new events to the stream.\n4. **Build Projections to the Read Side**: Create separate read models (projections) that are fed by subscriptions to the event stream. Implement back-pressure and retry policies for these subscriptions.\n5. **validate Full Observability**: Implement detailed logging that includes event IDs, sequence numbers, and metrics for tracking the lag time of each projection.\n\n## Key Deliverables\n- An Architecture Decision Record (ADR) detailing the aggregates, the chosen event store technology, the projection strategy, and the expected data consistency model (e.g., eventual consistency SLAs).\n- A suite of tests for command handlers that use in-memory event streams, complemented by integration tests for the projections.\n- Operational tooling for replaying events, taking state snapshots for performance, and managing schema migrations.\n\n## Risks & Mitigations\n- **High Operational Overhead**:\n  - **Mitigation**: Bugs related to event ordering and replays can be difficult to diagnose. Invest heavily in automation, Dead-Letter Queues (DLQs) for failed events, and regular \"chaos engineering\" drills to test resilience.\n- **Challenges of Eventual Consistency**:\n  - **Mitigation**: Users may be confused by delays between performing an action and seeing the result. Clearly document the SLAs for read model updates and manage user-facing expectations accordingly, for example, by providing immediate feedback on the command side.\n- **Schema Drift**:\n  - **Mitigation**: An unplanned change to an event schema can break consumers. Enforce the use of a formal schema registry and implement version gates in the CI/CD pipeline to prevent the emission of unvalidated event versions.\n## Troubleshooting\n\n### Common Issues\n\n**Command not found**\nEnsure all dependencies are installed and in PATH\n\n**Permission errors**\nCheck file permissions and run with appropriate privileges\n\n**Unexpected behavior**\nEnable verbose logging with `--verbose` flag\n\nFile v1.8.5:_meta.json\n\n{\n  \"ownerId\": \"kn7d107jg9jv602h9ytsegydq184a42s\",\n  \"slug\": \"nm-archetypes-architecture-paradigm-cqrs-es\",\n  \"version\": \"1.8.5\",\n  \"publishedAt\": 1778292918485\n}\n\nFile v1.8.5:skill-card.md\n\n## Description: <br>\nApply CQRS and Event Sourcing for read/write separation and audit trails. <br>\n\nThis skill is ready for commercial/non-commercial use. <br>\n\n## Publisher: <br>\n[athola](https://clawhub.ai/user/athola) <br>\n\n### License/Terms of Use: <br>\nMIT-0 <br>\n\n\n## Use Case: <br>\nDevelopers and software architects use this skill to evaluate and apply CQRS and Event Sourcing when systems need separated read/write workloads, durable audit trails, replayable event histories, or temporal queries. <br>\n\n### Deployment Geography for Use: <br>\nGlobal <br>\n\n## Known Risks and Mitigations: <br>\nRisk: Broad architecture and scalability triggers may activate CQRS/Event Sourcing guidance in discussions where the pattern is not a good fit. <br>\nMitigation: Confirm that the project needs separated read/write scaling, immutable audit history, replay, or temporal queries before applying the recommended architecture. <br>\nRisk: Pattern-specific guidance can add operational complexity if used for simple CRUD applications or small projects. <br>\nMitigation: Use simpler CRUD architecture when domain complexity, auditability, and projection requirements do not justify CQRS/Event Sourcing. <br>\n\n\n## Reference(s): <br>\n- [ClawHub Skill Page](https://clawhub.ai/athola/nm-archetypes-architecture-paradigm-cqrs-es) <br>\n- [OpenClaw Homepage](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes) <br>\n\n\n## Skill Output: <br>\n**Output Type(s):** [Guidance, Markdown] <br>\n**Output Format:** [Markdown prose with architecture steps, deliverables, risks, mitigations, and troubleshooting notes] <br>\n**Output Parameters:** [1D] <br>\n**Other Properties Related to Output:** [Read-only guidance; no external tools, credentials, or shell commands are required.] <br>\n\n## Skill Version(s): <br>\n1.8.5 (source: server release metadata; artifact frontmatter says 1.9.5) <br>\n\n## Ethical Considerations: <br>\nUsers should evaluate whether this skill is appropriate for their environment, review any generated or modified files before relying on them, and apply their organization's safety, security, and compliance requirements before deployment. <br>","readmeExcerpt":"Skill: architecture-paradigm-cqrs-es Owner: athola Summary: Applies CQRS and Event Sourcing for read/write separation and audit trails Tags: latest:1.9.19 Version history: v1.9.19 | 2026-08-26T13:05:01.256Z | user Release v1.9.19 v1.9.18 | 2026-08-15T21:28:59.341Z | user Release v1.9.18 v1.9.17 | 2026-07-30T05:28:49.006Z | user Release v1.9.17 v1.9.16 | 2026-07-14T19:45:57.363Z | user Release v1.9.16 v1.9.15 | 2026-0","codeSnippets":[],"executableExamples":[],"parameters":null,"dependencies":[],"permissions":[],"extractedFiles":[{"path":"SKILL.md","content":"---\nname: architecture-paradigm-cqrs-es\ndescription: Applies CQRS and Event Sourcing for read/write separation and audit trails\nversion: 1.9.8\ntriggers:\n  - architecture\n  - CQRS\n  - Event-Sourcing\n  - distributed-systems\n  - audit-trail\n  - scalability\n  - designing systems with complex domain logic or full state-change history\nmetadata: {\"openclaw\": {\"homepage\": \"https://github.com/athola/claude-night-market/tree/master/plugins/archetypes\", \"emoji\": \"\\ud83c\\udfd7\\ufe0f\"}}\nsource: claude-night-market\nsource_plugin: archetypes\n---\n\n> **Night Market Skill** — ported from [claude-night-market/archetypes](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes). For the full experience with agents, hooks, and commands, install the Claude Code plugin.\n\n\n# The CQRS and Event Sourcing Paradigm\n\n\n## When To Use\n\n- Designing event-sourced systems with complex domain logic\n- Systems requiring full audit trails of state changes\n\n## When NOT To Use\n\n- Simple CRUD applications without complex domain logic\n- Small projects where event sourcing adds unnecessary complexity\n\n## When to Employ This Paradigm\n- When read and write workloads have vastly different performance characteristics or scaling requirements.\n- When all business events must be captured in a durable, immutable history or audit trail.\n- When a business needs to rebuild projections of data or support temporal queries (e.g., \"What did the state of this entity look like yesterday?\").\n\n## Adoption Steps\n1. **Identify Aggregates**: Following Domain-Driven Design principles, specify the bounded contexts and the business invariants that each command must enforce on an aggregate.\n2. **Model Commands and Events**: Define the schemas and validation rules for all commands and the events they produce. Document a clear strategy for versioning and schema evolution.\n3. **Implement the Write Side (Command Side)**: Command handlers are responsible for loading an aggregate's event stream, executing business logic, and atomically appending new events to the stream.\n4. **Build Projections to the Read Side**: Create separate read models (projections) that are fed by subscriptions to the event stream. Implement back-pressure and retry policies for these subscriptions.\n5. **validate Full Observability**: Implement detailed logging that includes event IDs, sequence numbers, and metrics for tracking the lag time of each projection.\n\n## Key Deliverables\n- An Architecture Decision Record (ADR) detailing the aggregates, the chosen event store technology, the projection strategy, and the expected data consistency model (e.g., eventual consistency SLAs).\n- A suite of tests for command handlers that use in-memory event streams, complemented by integration tests for the projections.\n- Operational tooling for replaying events, taking state snapshots for performance, and managing schema migrations.\n\n## Risks & Mitigations\n- **High Operational Overhead**:\n  - **Mitigation**: Bugs related to event ordering and"},{"path":"_meta.json","content":"{\n  \"ownerId\": \"kn7d107jg9jv602h9ytsegydq184a42s\",\n  \"slug\": \"nm-archetypes-architecture-paradigm-cqrs-es\",\n  \"version\": \"1.9.19\",\n  \"publishedAt\": 1787749501256\n}"},{"path":"skill-card.md","content":"## Description:\n\nApplies CQRS and Event Sourcing for read/write separation and audit trails.\n\nThis skill is ready for commercial/non-commercial use.\n\n## Publisher:\n\n[athola](https://clawhub.ai/user/athola)\n\n### License/Terms of Use:\n\nMIT-0\n\n## Use Case:\n\nDevelopers and engineers use this skill during architecture discussions to decide when CQRS and Event Sourcing fit systems with complex domain logic, separated read and write workloads, durable audit trails, or projection rebuild needs.\n\n### Deployment Geography for Use:\n\nGlobal\n\n## Known Risks and Mitigations:\n\nRisk: The skill may surface during broad architecture or scalability discussions where CQRS and Event Sourcing are not the right default.\n\nMitigation: Treat the guidance as pattern-specific and first confirm needs such as complex domain logic, separated read and write workloads, durable audit trails, or projection rebuilds.\n\nRisk: CQRS and Event Sourcing can add operational overhead through event ordering, replay, projection lag, and recovery workflows.\n\nMitigation: Use automation, dead-letter handling, projection monitoring, replay tooling, and documented consistency expectations before adopting the pattern.\n\nRisk: Event schema changes can break consumers or projections.\n\nMitigation: Define event schemas and versioning rules up front, and use validation gates before new event versions are emitted.\n\n## Reference(s):\n\n- [ClawHub skill page](https://clawhub.ai/athola/skills/nm-archetypes-architecture-paradigm-cqrs-es)\n- [Night Market archetypes source](https://github.com/athola/claude-night-market/tree/master/plugins/archetypes)\n\n## Skill Output:\n\n**Output Type(s):** [Guidance, Markdown]\n\n**Output Format:** [Markdown prose with architecture adoption steps, deliverables, component vocabulary, risks, and mitigations.]\n\n**Output Parameters:** [1D]\n\n**Other Properties Related to Output:** [Non-executable architecture guidance; no API keys, MCP tools, or shell commands detected.]\n\n## Skill Version(s):\n\n1.9.19 (source: server release evidence; artifact frontmatter reports 1.9.8)\n\n## Ethical Considerations:\n\nUsers should evaluate whether this skill is appropriate for their environment, review any generated or modified files before relying on them, and apply their organization's safety, security, and compliance requirements before deployment."}],"languages":[],"docsSourceLabel":"CLAWHUB","editorialOverview":"Applies CQRS and Event Sourcing for read/write separation and audit trails Skill: architecture-paradigm-cqrs-es Owner: athola Summary: Applies CQRS and Event Sourcing for read/write separation and audit trails Tags: latest:1.9.19 Version history: v1.9.19 | 2026-08-26T13:05:01.256Z | user Release v1.9.19 v1.9.18 | 2026-08-15T21:28:59.341Z | user Release v1.9.18 v1.9.17 | 2026-07-30T05:28:49.006Z | user Release v1.9.17 v1.9.16 | 2026-07-14T19:45:57.363Z | user Release v1.9.16 v1.9.15 | 2026-0","editorialQuality":{"score":100,"threshold":65,"status":"ready","wordCount":1133,"uniquenessScore":52,"reasons":[]}},"media":{"evidence":{"source":"no-media","verified":false,"confidence":"low","updatedAt":"2026-10-10T01:24:27.799Z","emptyReason":"No screenshots, media assets, or demo links are available."},"primaryImageUrl":null,"mediaAssetCount":0,"assets":[],"demoUrl":null},"ownerResources":{"evidence":{"source":"unclaimed","verified":false,"confidence":"low","updatedAt":"2026-10-10T01:24:27.799Z","emptyReason":"This page has not been claimed by the agent owner."},"hasCustomPage":false,"customPageUpdatedAt":null,"customLinks":[],"structuredLinks":{"docsUrl":null,"demoUrl":null,"supportUrl":null,"pricingUrl":null,"statusUrl":null},"customPage":null},"relatedAgents":{"evidence":{"source":"protocol-neighbors","verified":false,"confidence":"medium","updatedAt":"2026-10-10T08:12:52.563Z","emptyReason":null},"items":[{"id":"8ebccd8e-3863-4187-8355-c3f14e1f9edf","entityType":"agent","canonicalPath":"/agent/iofficeai-aionui","slug":"iofficeai-aionui","name":"AionUi","description":"Free, local, open-source 24/7 Cowork app and OpenClaw for Gemini CLI, Claude Code, Codex, OpenCode, Qwen Code, Goose CLI, Auggie, and more | 🌟 Star if you like it!","url":"https://github.com/iOfficeAI/AionUi","homepage":"https://www.aionui.com","source":"GITHUB_REPOS","protocols":["MCP","OPENCLAW"],"capabilities":[],"safetyScore":100,"overallRank":70,"updatedAt":"2026-10-09T19:11:12.944Z","createdAt":"2026-02-25T03:38:16.584Z","downloads":null},{"id":"b917f68a-ebff-438e-84f8-3f4b2494c0bc","entityType":"agent","canonicalPath":"/agent/activepieces-activepieces","slug":"activepieces-activepieces","name":"activepieces","description":"AI Agents & MCPs & AI Workflow Automation • (~400 MCP servers for AI agents) • AI Automation / AI Agent with MCPs • AI Workflows & AI Agents • MCPs for AI Agents","url":"https://github.com/activepieces/activepieces","homepage":"https://www.activepieces.com","source":"GITHUB_REPOS","protocols":["OPENCLAW"],"capabilities":[],"safetyScore":100,"overallRank":70,"updatedAt":"2026-04-15T02:22:12.426Z","createdAt":"2026-02-25T03:38:12.412Z","downloads":null},{"id":"5cb26759-3a39-483f-94cf-276a98c13bb8","entityType":"agent","canonicalPath":"/agent/cherryhq-cherry-studio","slug":"cherryhq-cherry-studio","name":"cherry-studio","description":"AI productivity studio with smart chat, autonomous agents, and 300+ assistants. 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