Where does your front end dev sit?

Hi I manage a CX team of writers, trainers, UI architects, and designers. I'm working to expand our capability by adding front end devs so we can have better relationships with the developers via the front end dev, or translator. I am wondering where your front ends sit? Do they sit with UX or sit in engineering? I report up to marketing instead of engineering which is also a bit different than the norm.

Some of the problems I am trying to solve are:

  1. Build reusable code and libraries for future use
  2. Ensure the technical feasibility of UI/UX designs
  3. Optimize application for maximum speed and scalability
  4. Assure that all user input is validated before submitting to back-end
  5. Serve as translator between dev and UX

Thank you for your help!