What is the Behavior-First Principle in this skill?

It is a methodology where tests are only created for results observable by the user, requiring integration of multiple components and stable automation in CI environments.

Does this skill support property-based testing?

Yes, it specifically includes rules for implementing fast-check to verify invariants and automatically generate regression tests for discovered failures.

How does the skill calculate Test ROI?

ROI is calculated by weighing business value, frequency, and legal requirements against the total cost of implementation and maintenance.

When should I use mocks instead of actual components?

Mocks are required for external network communication in integration tests, while actual components are required for the specific logic under test or for any E2E test scenario.

Integration & E2E Test Designer

Name: Integration & E2E Test Designer
Author: shinpr

byshinpr

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152

セキュリティとテスト

Designs high-ROI integration and E2E tests using behavior-first principles and property-based verification patterns.

概要

This skill provides a comprehensive framework for architecting robust test suites within Claude Code, focusing on integration and end-to-end (E2E) layers. It enforces a behavior-first philosophy, ensuring that tests target observable results and critical user journeys rather than brittle implementation details. By utilizing specialized ROI calculations, property-based testing via fast-check, and strict mock boundary rules, this skill helps developers create lean, high-value test suites that maintain system integrity and improve CI/CD stability.

主な機能

ROI-based test prioritization to focus on high-value business and legal logic
152 GitHub stars
Property-based testing integration using the fast-check library for invariant verification
Strict mock boundary rules to differentiate between integration and full-system testing
Behavior-first test design focusing on observable user results and system context
Standardized test skeletons including Acceptance Criteria, ROI, and complexity metadata

ユースケース

Implementing property-based tests to ensure data integrity across various edge cases
Defining clear boundaries between mocked integration tests and full-system E2E verifications
Automating the creation of test suites for critical user journeys with high revenue impact

概要

主な機能

ROI-based test prioritization to focus on high-value business and legal logic
152 GitHub stars
Property-based testing integration using the fast-check library for invariant verification
Strict mock boundary rules to differentiate between integration and full-system testing
Behavior-first test design focusing on observable user results and system context
Standardized test skeletons including Acceptance Criteria, ROI, and complexity metadata

ユースケース

Implementing property-based tests to ensure data integrity across various edge cases
Defining clear boundaries between mocked integration tests and full-system E2E verifications
Automating the creation of test suites for critical user journeys with high revenue impact