Nope. The compartment in the rear is user-serviceable, you can replace RAM and drives as much as you want (well, not really, the contacts will break after a while if you do that 😄 ). You can install up to 2 sticks of 8GB so make sure you CAN upgrade before you buy anything.
Just be careful when putting the screws back, don't tighten them too much or the nests will break.