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

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Security & Testing

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

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.

Key Features

01ROI-based test prioritization to focus on high-value business and legal logic

02152 GitHub stars

03Property-based testing integration using the fast-check library for invariant verification

04Strict mock boundary rules to differentiate between integration and full-system testing

05Behavior-first test design focusing on observable user results and system context

06Standardized test skeletons including Acceptance Criteria, ROI, and complexity metadata

Use Cases

01Implementing property-based tests to ensure data integrity across various edge cases

02Defining clear boundaries between mocked integration tests and full-system E2E verifications

03Automating the creation of test suites for critical user journeys with high revenue impact

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add shinpr/ai-coding-project-boilerplate integration-e2e-testing

For use in Claude.ai and ChatGPT

Download Skill