Worked on the unslothai/unsloth repository, focusing on enhancing the reliability and maintainability of backend code. Developed two features, including improvements to the grpo_trainer module by preserving original indentation when replacing the 'return output' statement, utilizing Python and regular expressions to ensure output formatting remained consistent. Transitioned from f-string triple-quoted strings to explicit newline construction, which improved code readability and maintainability. Additionally, performed codebase cleanup by removing unnecessary comments, further supporting clean code practices. The work demonstrated attention to detail in backend development, emphasizing maintainable and readable Python code without introducing new bugs during the development period.