Your code has a race condition. It just hasn't lost yet.

Unprotected shared state, missing locks, and async/await pitfalls are ticking time bombs. ConcurrencyGuard scans your codebase and defuses every single one — across 6 languages, 90+ patterns, 100% locally.

$ clawhub install concurrencyguard click to copy
$ concurrencyguard scan
⚡ ConcurrencyGuard v1.0.0
 
Scanning 47 files...
 
  src/cache/store.ts:34
    ✗ [SS-002] Shared mutable state without synchronization
    → Wrap access in Mutex<Map> or use ConcurrentMap
 
  src/services/payment.go:78
    ✗ [LK-005] Goroutine accesses shared map without sync.RWMutex
    → Protect with sync.RWMutex or use sync.Map
 
  src/auth/session.py:15
    ✗ [TC-001] TOCTOU race — check-then-act on file without lock
    → Use atomic operation: os.open(path, os.O_CREAT | os.O_EXCL)
 
  src/api/handlers.ts:92
    ✗ [AW-003] Unguarded shared state mutation inside async function
    → Serialize access with async-mutex or extract to atomic update
 
  ───────────────────────────────────────
  Score: 28/100 (Grade: F)  |  5 critical  4 high  3 medium

Race conditions are the hardest bugs to reproduce — and the easiest to ship.

Every unprotected shared variable is a Heisenbug waiting to happen. Every missing lock is a data corruption you won't see until 3 AM in production. ConcurrencyGuard scans your codebase statically and gives you a clear fix for every hazard it finds.

90+
Detection patterns
6
Languages supported
6
Hazard categories
100%
Local analysis

What ConcurrencyGuard Catches

📦
SS

Shared State Hazards

Detects unprotected mutable shared variables, global state mutations across threads, and concurrent collection access without synchronization. The #1 source of race conditions.

🔐
LK

Missing Locks & Mutexes

Finds goroutine map access without sync.RWMutex, Java fields missing synchronized, Python threading without Lock, and C# shared access without lock blocks.

⏱️
TC

TOCTOU Vulnerabilities

Catches time-of-check to time-of-use races: file existence checks before writes, permission checks before access, and database read-then-update without transactions.

🔄
AW

Async/Await Pitfalls

Identifies shared state mutations inside async functions, missing await on concurrent operations, Promise.all with shared mutable refs, and unguarded event-loop re-entry.

🏢
TS

Thread-Unsafe Singletons

Flags lazy singletons without double-checked locking, non-volatile instance fields in Java, Python module-level mutable state used across threads, and unsafe static initializers.

🗄️
DL

Missing Transaction Isolation

Detects database read-modify-write without proper isolation levels, missing SELECT FOR UPDATE, concurrent counter increments without atomics, and optimistic locking gaps.

Without / With ConcurrencyGuard

Scenario Without With ConcurrencyGuard
Shared map accessed by goroutines Panic at random in production Flagged at commit time with fix
Async function mutating outer variable Silent data corruption AW-003 with mutex suggestion
File check-then-write race Security vulnerability shipped TC-001 with atomic alternative
Lazy singleton without DCL Double initialization under load TS-002 with safe pattern
Counter increment without transaction Lost updates, wrong totals DL-004 with isolation fix
Java field missing synchronized Intermittent test failures LK-001 caught in pre-commit
Promise.all with shared mutable ref Nondeterministic results AW-007 with immutable approach
Python global dict in threaded server Request data leaked between users SS-009 with threading.Lock fix
Rust Arc without Mutex inner Won't compile (Rust catches it!) Still flagged for clarity

Simple, transparent pricing

Start scanning for free. Upgrade when your codebase demands it.

Free
$0
  • Basic concurrency scan
  • All 90+ detection patterns
  • Terminal report output
  • Pre-commit hook
  • Community support
Install Free
Team
$39/mo
  • Everything in Pro
  • Team-wide report dashboard
  • Baseline & trend tracking
  • Custom ignore rules
  • SARIF output
  • Priority support

Get notified about updates

No spam. One email per week max. Unsubscribe anytime.

Race conditions don't announce themselves — until it's too late

Install ConcurrencyGuard in 30 seconds. Find every unprotected shared state, missing lock, and async hazard in your codebase.

$ clawhub install concurrencyguard click to copy