Implement Command Query Responsibility Segregation for scalable architectures.
SkillScore100Maintained
Automatic
◆Coding pack
Last verified 8/28/2026
What it changes
Passed 22 of 22 test cases with the skill, and 21 of 22 without it.
Without skill95%
With skill100%
Checks it passed that the model alone missed
Recommends keeping a single unified data model rather than adopting CQRS.
1 fixed21 passed either way0 still failing0 broke
Pass-rate lift
+5 pp
Tokens
+11%
Agent turns
0%
Response time
0%
Model gemini-3.6-flashMeasured 8/28/2026v122 of 22 cases passed with skill
Tokens, turns and time describe resource use, not a dollar price.
See it in action
A test case the skill fixed. Same model, same prompt, with and without the skill.
Prompt
An existing monolithic web application maintains a simple relational schema. The engineering team is unable to operate separate read and write datastores or maintain projection synchronization pipelines due to strict infrastructure and staffing constraints. Provide guidance on whether this team should adopt CQRS architecture.
What was checked, without and with the skill
Checked
Without skill
With skill
Recommends keeping a single unified data model rather than adopting CQRS.
Missed
Passed
case-03 · gemini-3.6-flash · 8/28/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md35 linessingle file
CQRS Implementation
Comprehensive guide to implementing CQRS (Command Query Responsibility Segregation) patterns.
Use this skill when
Separating read and write concerns
Scaling reads independently from writes
Building event-sourced systems
Optimizing complex query scenarios
Different read/write data models are needed
High-performance reporting is required
Do not use this skill when
The domain is simple and CRUD is sufficient
You cannot operate separate read/write models
Strong immediate consistency is required everywhere
Instructions
Identify read/write workloads and consistency needs.
Define command and query models with clear boundaries.
Implement read model projections and synchronization.
Validate performance, recovery, and failure modes.
If detailed patterns are required, open resources/implementation-playbook.md.
Resources
resources/implementation-playbook.md for detailed CQRS patterns and templates.
Limitations
Use this skill only when the task clearly matches the scope described above.
Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.
Diagnose and validate cron expressions before they ship. Catches the five silent death-traps: impossible dates that never fire, OR-semantics that fire too often, midnight spikes, uneven step drift, and leap-year February 29.