I know exactly what you are looking for. I have a good experience working in Hibernate or Spring whatever you are in need, from my side I would like to suggest you as you are in need of a pilot project, so Spring would be a suitable Framework. As Java's robustness and scalable behaviour will make it already secure, So security would not be a big concern on that.
About Algorithms, I have a good understanding of all the already build algorithms and if required I can create new and much more optimized algorithms.