Who are some famous ancient Roman inventors?

The Romans made quite a number of inversions, particularly in the fields of engineering and architecture. However, were do not know much about their inventors. The Romans did not write about their inventors or their inventions. All were have is a textbook in architecture and engineering by a called Vitruvius. However, he only gave descriptions and did not mention about inventions or inventors. Some of our knowledge about Roman inventions even comes from Archaeology, rather than writings by the Romans.