During December 2025, contributed to the nestjs/nest repository by developing an integration test focused on dependency injection (DI) scope bubbling. The work involved verifying that a Singleton service correctly downgrades to Request-Scoped when it depends on a Request-Scoped service, ensuring the DI container maintains proper scope relationships and preventing regressions. This addition improved test coverage for DI lifetimes and reinforced the reliability of scope management within the framework. The approach emphasized regression testing and continuous integration readiness, utilizing TypeScript and NestJS testing utilities to validate DI behavior and support stable, maintainable releases without introducing new bugs or regressions.