The Numerical Algorithms Group Ltd
"NAG are specialists in providing Numerical algorithms to solve complex computational problems across a number of verticals (including automated differentiation). The NAG library is the largest set of numerical algorithms in the world and has been used in indutry and academia for nearly 50 years.
NAG also has excellent credentials in High Performance Computing working with all three major cloud vendors (AWS/Azure/GCP) vastly experienced in designing and supporting Op premise, Hybrid and Cloud environments"