Ultimate Bug Scanner - scan code for bugs across 7 languages (JS/TS, Python, Go, Rust, Java, C++, Ruby). Use before commits to catch null safety issues, security holes, async bugs, and memory leaks.
Install
npx skillscat add johnlindquist/claude/ubs Install via the SkillsCat registry.
We need to produce a 2-3 sentence plain-text summary, objective, factual, no marketing language, no superlatives, no calls to action. At most 60 words. Must be plain text, no markdown, no bullet points, no headings. Must not wrap in quotes. So just output the summary. We need to explain: what this skill does (Ultimate Bug Scanner scans code for bugs across 7 languages, catches null safety issues, security holes, async bugs, memory leaks). Problem it solves: catches real bugs before commits, static analysis. When to use: before commits, in CI, to catch bugs early.
UBS - Ultimate Bug Scanner
Fast static analysis that catches real bugs across multiple languages in seconds.
Prerequisites
Install UBS:
curl -sSL https://raw.githubusercontent.com/Dicklesworthstone/ultimate_bug_scanner/main/install.sh | bashDependencies (auto-detected):
rg(ripgrep) - Pattern matchingast-grep- AST analysisjq- JSON processing
CLI Reference
Basic Scanning
# Scan specific files (fastest, <1s)
ubs file.ts file2.py
# Scan directory
ubs src/
# Scan current directory
ubs .
# Scan staged files (pre-commit)
ubs --staged
# Scan modified files (working tree vs HEAD)
ubs --diffOutput Formats
# Text (default)
ubs src/
# JSON
ubs src/ --format=json
# JSONL (streaming)
ubs src/ --format=jsonl
# SARIF (for CI integration)
ubs src/ --format=sarifStrictness Modes
# Strict - fail on warnings
ubs src/ --fail-on-warning
ubs src/ --ci --fail-on-warning
# CI mode
ubs src/ --ci
# Quiet (summary only)
ubs src/ -qLanguage Filtering
# Only specific languages (3-5x faster)
ubs src/ --only=js,python
ubs src/ --only=typescript,rust
ubs src/ --only=go,javaCategory Filtering
# Focus on specific category packs
ubs src/ --category=resource-lifecycleVerbose Mode
# Show more code examples per finding
ubs src/ --verboseBaseline Comparison
# Save baseline
ubs src/ --format=json > baseline.json
# Compare against baseline (detect regressions)
ubs src/ --comparison=baseline.json
# Generate reports
ubs src/ --comparison=baseline.json --report-json=report.json --html-report=report.htmlDoctor/Health Check
# Check installation and dependencies
ubs doctorView Session Logs
# Tail latest session log
ubs sessions --entries 1Output Format
Warning/Error: Category (N errors)
file.ts:42:5 - Issue description
Suggested fix
Exit code: 1Parse format:
file:line:col- LocationSuggested fix- How to fix- Exit 0/1 - Pass/fail
Bug Categories Detected
Critical (Always Fix)
- Null/undefined safety issues
- XSS and injection vulnerabilities
- async/await problems
- Memory leaks
- Use-after-free
Important (Production)
- Type narrowing issues
- Division by zero risks
- Resource leaks (unclosed handles)
- Race conditions
Contextual (Use Judgment)
- TODO/FIXME comments
- Console.log statements
- Dead code
Workflow Patterns
Pre-Commit Hook
# In .git/hooks/pre-commit
#!/bin/bash
ubs --staged --fail-on-warning || exit 1CI Pipeline
# Strict mode for CI
ubs . --ci --fail-on-warningQuick Check During Development
# Scan just the file you're working on
ubs src/component.tsx
# Scan modified files
ubs --diffFixing Findings
- Read the finding (category + description)
- Navigate to
file:line:col - View context
- Verify it's a real issue (not false positive)
- Fix the root cause, not symptom
- Re-run
ubs <file>to verify - Exit code 0 = fixed
Speed Tips
- Scope to changed files -
ubs src/file.ts(<1s) vsubs .(30s) - Use language filter -
--only=js,pythonfor 3-5x speedup - Never full scan for small edits - Always scope to modified files
Anti-Patterns
| Don't | Do |
|---|---|
| Ignore findings | Investigate each |
| Full scan per edit | Scope to changed files |
Fix symptom (if (x) { x.y }) |
Fix root cause (x?.y) |
| Add suppression comments | Fix the actual issue |
Best Practices
- Run before every commit -
ubs --staged - Exit 0 = safe to commit - Exit >0 = fix and re-run
- Trust the suggestions - They point to real issues
- Fix root cause - Don't just silence the warning
- Use in CI - Catch regressions before merge