check-concurrency

Detect race conditions, deadlocks, and unsafe shared state in Java codebases.

4|Updated May 26, 2025
One-click install
npx skills add https://github.com/pwittchen/varun.surf --skill check-concurrency
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: check-concurrency
Source: https://github.com/pwittchen/varun.surf/tree/main/.claude/skills/check-concurrency
Command: npx skills add https://github.com/pwittchen/varun.surf --skill check-concurrency

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Concurrency bugs such as race conditions, deadlocks, and unsafe shared state slow down development and lead to flaky behavior. This Skill helps identify these issues early by analyzing code patterns and recommending safer synchronization strategies.

Core Features & Use Cases

  • Identify common concurrency anti-patterns like unsynchronized shared mutable state, check-then-act, and non-atomic increments.
  • Recommend safe replacements using ConcurrentHashMap, atomic primitives, and thread-safe collections.
  • Apply to multi-threaded Java services, background workers, and request handling paths where concurrency issues are likely.

Quick Start

Audit your codebase for concurrency patterns and generate safe replacements for shared mutable state.

Frequently Asked Questions about check-concurrency

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I find race conditions and deadlocks in a Java codebase?

To find race conditions and deadlocks in a Java codebase, inspect multi-threaded code patterns for unsynchronized shared mutable state and unsafe thread interactions. This process identifies check-then-act sequences and non-atomic operations to produce actionable safety recommendations.

What are common concurrency anti-patterns in Java background workers?

Common concurrency anti-patterns in Java background workers include unsynchronized shared mutable state, check-then-act logic errors, and non-atomic increments. Identifying these unsafe shared state patterns helps prevent flaky behavior and thread interference in multi-threaded service workflows.

How do I replace unsafe shared mutable state with thread-safe collections in Java?

Replace unsafe shared mutable state in Java by using thread-safe collections like ConcurrentHashMap and atomic primitives. Applying these safer synchronization strategies to multi-threaded services and request handling paths ensures proper synchronization across concurrent components.

Can I audit Java schedulers and caches for thread safety issues?

Yes, you can audit Java schedulers and caches for thread safety issues by inspecting multi-threaded components for proper synchronization primitives. Analyzing request-handling and background-task workflows identifies unsafe shared state and concurrency bugs across these services.

What is the best way to prevent deadlocks in Java multi-threaded services?

The best way to prevent deadlocks in Java multi-threaded services is to inspect code patterns and apply proper synchronization primitives. Analyzing typical request-handling workflows and background-task components ensures safe replacements for unsafe shared state.