Worked on enhancing the security and reliability of package management in the ocaml/dune and Leonidas-from-XIV/dune repositories. Developed a secure package locking feature in ocaml/dune by enforcing stronger hash algorithms for package checksums, which improved integrity and reduced tampering risks. Addressed a bug in Leonidas-from-XIV/dune by fixing the locking of relative paths outside the workspace, aligning behavior with Opam and improving usability for developers. Utilized OCaml for both feature development and bug fixing, applying package management expertise and security best practices to deliver cross-repository improvements that benefit developer workflows and continuous integration environments.