3. Add tests
4. Handle resources properly (try-with-resources)
5. Consider thread safety
6. Update JavaDoc

### When Fixing Bugs

1. Write failing test first
2. Understand root cause
3. Minimal changes
4. Verify no regressions

### When Refactoring

1. Preserve behavior
2. Keep tests green
3. Small incremental steps
4. Don't mix with new features

### Code Quality Checklist

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labels.boostExpr=Wyrażenie wzmocnienia
labels.confirmPassword=Potwierdź
labels.crawler=Crawler
labels.crudMode=Tryb
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labels.geo=Geo
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labels.order=Kolejność

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labels.hash=Hash
labels.maxSize=Maximale grootte
labels.order=Volgorde