Yitong Li enhanced backend reliability and automation across several repositories, focusing on robust cross-environment migrations and improved error handling. In topoteretes/cognee, Yitong ensured migration scripts consistently used the correct Python interpreter, particularly addressing Windows environments, and added end-to-end tests for validation. For Mintplex-Labs/anything-llm, Yitong implemented logic to infer file extensions from Content-Type headers, reducing processing errors when handling files without explicit extensions. In livekit/agents, Yitong strengthened LLM function call validation by surfacing detailed error messages and improving logging. Throughout these projects, Yitong applied Node.js, Python, and test-driven development to deliver maintainable, production-ready backend solutions.