Installed WPMU DEV on client's site

I did some freelance work for a client, and installed WPMU DEV on their Wordpress. I used Fixer theme and Upfront to create a great site, and am now finished with the work for the client. My questions is: do I need to leave WPMU DEV installed on her Wordpress in order for everything to work properly? Or now that the site is complete can I remove WPMU DEV without breaking anything?

Thanks!