Worked on the nestjs/nest repository to address a complex issue with dependency resolution for request-scoped providers in lazy-loaded modules. Focused on backend development using TypeScript and NestJS, the work involved fixing a bug that previously caused incorrect resolution of dependencies in advanced module graphs. The approach included adjusting the module and provider resolution logic to ensure that request-scoped services functioned correctly across lazy boundaries, thereby reducing runtime errors in large applications. Comprehensive tests were added to validate the new logic, reinforcing the reliability of dependency injection lifecycles and improving the stability of request-scoped services in modular architectures.