EventLint -- Event & Message Queue Anti-Pattern Analyzer
EventLint scans codebases for event-driven architecture anti-patterns, producer/consumer issues, schema validation gaps, dead letter queue misconfigurations, ordering and delivery failures, and observability gaps across Kafka, RabbitMQ, SQS, NATS, and Redis Pub/Sub. It uses regex-based pattern matching against 90 event-specific patterns across 6 categories, lefthook for git hook integration, and produces markdown reports with actionable remediation guidance. 100% local. Zero telemetry.
Commands
Free Tier (No license required)
eventlint scan [file|directory]
One-shot event architecture quality scan of files or directories.
How to execute:
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [target]
What it does:
- Accepts a file path or directory (defaults to current directory)
- Discovers all source files (skips .git, node_modules, binaries, images, .min.js)
- Runs 30 event architecture patterns against each file (free tier limit)
- Calculates an event architecture quality score (0-100) per file and overall
- Grades: A (90-100), B (80-89), C (70-79), D (60-69), F (<60)
- Outputs findings with: file, line number, check ID, severity, description, recommendation
- Exit code 0 if score >= 70, exit code 1 if event quality is poor
- Free tier limited to first 30 patterns (PP + CP categories)
Example usage scenarios:
- "Scan my code for event issues" -> runs
eventlint scan .
- "Check this file for consumer anti-patterns" -> runs
eventlint scan src/consumer.ts
- "Find missing dead letter queues" -> runs
eventlint scan src/
- "Audit my Kafka configuration" -> runs
eventlint scan .
- "Check for message ordering problems" -> runs
eventlint scan .
Pro Tier ($19/user/month -- requires EVENTLINT_LICENSE_KEY)
eventlint scan --tier pro [file|directory]
Extended scan with 60 patterns covering producer, consumer, schema, and dead letter patterns.
How to execute:
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [target] --tier pro
What it does:
- Validates Pro+ license
- Runs 60 event architecture patterns (PP, CP, MS, ED categories)
- Detects schema validation gaps and breaking changes
- Identifies dead letter queue misconfigurations
- Full category breakdown reporting
eventlint scan --format json [directory]
Generate JSON output for CI/CD integration.
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --format json
eventlint scan --format html [directory]
Generate HTML report for browser viewing.
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --format html
eventlint scan --category ED [directory]
Filter scan to a specific check category (PP, CP, MS, ED, OD, EO).
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --category ED
Team Tier ($39/user/month -- requires EVENTLINT_LICENSE_KEY with team tier)
eventlint scan --tier team [directory]
Full scan with all 90 patterns across all 6 categories including ordering/delivery and observability.
How to execute:
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --tier team
What it does:
- Validates Team+ license
- Runs all 90 patterns across 6 categories
- Includes ordering & delivery detection (dual-write, missing outbox, race conditions)
- Includes event observability checks (no tracing, missing metrics, no audit trail)
- Full category breakdown with per-file results
eventlint scan --verbose [directory]
Verbose output showing every matched line and pattern details.
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --verbose
eventlint status
Show license and configuration information.
bash "<SKILL_DIR>/scripts/dispatcher.sh" status
Check Categories
EventLint detects 90 event architecture anti-patterns across 6 categories:
| Category | Code | Patterns | Description | Severity Range |
|---|
| Producer Patterns | PP | 15 | Fire-and-forget publish, missing keys, no schema validation, acks=0 | medium -- critical |
| Consumer Patterns | CP | 15 | No idempotency, auto-ack, unbounded prefetch, blocking handlers | low -- critical |
| Message Schema | MS | 15 | No schema registry, unversioned, breaking changes, loose typing | low -- critical |
| Error & Dead Letter | ED | 15 | Missing DLQ, infinite redelivery, swallowed exceptions, no poison handling | low -- critical |
| Ordering & Delivery | OD | 15 | Dual-write, no outbox, missing dedup, saga without timeout | low -- critical |
| Event Observability | EO | 15 | No tracing, missing metrics, no audit trail, no alerting | low -- medium |
Tier-Based Pattern Access
| Tier | Patterns | Categories |
|---|
| Free | 30 | PP, CP |
| Pro | 60 | PP, CP, MS, ED |
| Team | 90 | PP, CP, MS, ED, OD, EO |
| Enterprise | 90 | PP, CP, MS, ED, OD, EO + priority support |
Scoring
EventLint uses a deductive scoring system starting at 100 (perfect):
| Severity | Point Deduction | Description |
|---|
| Critical | -25 per finding | Severe reliability issue (message loss, infinite redelivery, dual-write) |
| High | -15 per finding | Significant event problem (missing DLQ, auto-ack, no idempotency) |
| Medium | -8 per finding | Moderate concern (missing correlation ID, unversioned schema) |
| Low | -3 per finding | Informational / best practice suggestion |
Grading Scale
| Grade | Score Range | Meaning |
|---|
| A | 90-100 | Excellent event architecture quality |
| B | 80-89 | Good architecture with minor issues |
| C | 70-79 | Acceptable but needs improvement |
| D | 60-69 | Poor event architecture quality |
| F | Below 60 | Critical event architecture problems |
- Pass threshold: 70 (Grade C or better)
- Exit code 0 = pass (score >= 70)
- Exit code 1 = fail (score < 70)
Configuration
Users can configure EventLint in ~/.openclaw/openclaw.json:
{
"skills": {
"entries": {
"eventlint": {
"enabled": true,
"apiKey": "YOUR_LICENSE_KEY_HERE",
"config": {
"severityThreshold": "medium",
"ignorePatterns": ["**/test/**", "**/fixtures/**", "**/*.test.*"],
"ignoreChecks": [],
"reportFormat": "text"
}
}
}
}
}
Important Notes
- Free tier works immediately with no configuration
- All scanning happens locally -- no code is sent to external servers
- License validation is offline -- no phone-home or network calls
- Pattern matching only -- no AST parsing, no external dependencies beyond bash
- Supports scanning all file types in a single pass
- Git hooks use lefthook which must be installed (see install metadata above)
- Exit codes: 0 = pass (score >= 70), 1 = fail (for CI/CD integration)
- Output formats: text (default), json, html
Error Handling
- If lefthook is not installed and user tries hooks, prompt to install it
- If license key is invalid or expired, show clear message with link to https://eventlint.pages.dev/renew
- If a file is binary, skip it automatically with no warning
- If no scannable files found in target, report clean scan with info message
- If an invalid category is specified with --category, show available categories
When to Use EventLint
The user might say things like:
- "Scan my code for event issues"
- "Check my message queue patterns"
- "Find missing dead letter queues"
- "Detect fire-and-forget publishing"
- "Are there any consumer anti-patterns?"
- "Check for schema validation gaps"
- "Audit my Kafka configuration"
- "Find ordering and delivery issues"
- "Check for dual-write problems"
- "Scan for event observability gaps"
- "Run an event architecture audit"
- "Generate an event quality report"
- "Check if my consumers have idempotency"
- "Find missing DLQ configuration"
- "Check my code for auto-ack issues"
