Worked on the openssl/openssl repository to optimize ML-DSA cryptographic workloads for s390x enterprise hardware. Developed a vectorized implementation of the number theoretic transform (NTT) using C, leveraging 128-bit vector registers and the vec_mulh instruction to accelerate both forward and inverse NTT paths. This approach resulted in a throughput increase of approximately two to three times on z17-class systems. The work demonstrated expertise in low-level programming, cryptography, and performance optimization, and involved close collaboration with project maintainers to ensure correctness and maintainability. The feature was reviewed, approved, and merged, aligning with OpenSSL’s performance roadmap.