Which programming languages does this skill support?

The skill supports over 8 languages, with dedicated patterns for Rust (contracts crate), TypeScript (Zod), Python (icontract), Java (Guava), C++, and Kotlin.

Does using contracts impact production performance?

The skill utilizes a verification hierarchy that prioritizes compile-time assertions and allows you to toggle between debug-only and production-ready runtime checks.

How does this skill help with debugging?

It provides a remediation workflow that automatically categorizes violations as caller-side (precondition) or callee-side (postcondition/invariant) and suggests specific fix strategies.

What is the difference between a precondition and a postcondition?

A precondition defines the requirements the caller must meet before a function executes, while a postcondition defines the guarantees the function must provide upon completion.

Where are the contract definitions stored?

Generated contract artifacts and schemas are organized within a dedicated .outline/contracts/ directory to maintain a clean separation of concerns.

Design-by-Contract Developer

Name: Design-by-Contract Developer
Author: Activer007

byActiver007

0•

Security & Testing

Implements formal contract verification using preconditions, postconditions, and invariants across multiple programming languages to ensure code reliability.

This skill provides a comprehensive framework for Design-by-Contract (DbC) development, enabling developers to define formal specifications for component behavior. It automates the entire lifecycle—from planning predicates and generating language-specific annotations to runtime verification and automated remediation of contract violations. By integrating formal contracts into the development workflow, it helps maintain state consistency, validates API boundaries, and ensures business logic correctness using a structured verification hierarchy that supports Rust, TypeScript, Python, Java, and more.

Key Features

01Automated contract generation for 8+ languages including Rust, Python, and TypeScript

020 GitHub stars

03Structured verification hierarchy prioritizing compile-time safety over runtime checks

04Integrated debugging strategies for rapid remediation of contract violations

05Full PLAN-CREATE-VERIFY-REMEDIATE workflow automation

06Support for formal preconditions, postconditions, and class invariants

Use Cases

01Maintaining complex internal state invariants in safety-critical applications

02Ensuring business logic correctness through formal postcondition guarantees

03Securing public API boundaries with robust input and output validation

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add activer007/ordinary-claude-skills design-by-contract

For use in Claude.ai and ChatGPT

Download Skill