# Guides
In-depth guides for specific topics.
- [Format Selection](format-selection.md) - Choosing the right serialization format
- [Migration from pymarc](migration-from-pymarc.md) - Migrating existing pymarc code
- [Working with Large Files](working-with-large-files.md) - Processing large MARC files efficiently
- [Threading (Python)](threading-python.md) - Parallel processing in Python
- [Performance Tuning](performance-tuning.md) - Optimizing MRRC performance
- [Query DSL](query-dsl.md) - Advanced field querying
- [BIBFRAME Conversion](bibframe-conversion.md) - Converting MARC to BIBFRAME RDF