That’s due to swelling batteries, which is apparently common in the xps line
Get something with a bit of thickness to it, like the Latitude 5530 (which Dell will also sell with Ubuntu) and stick to the low-TDP CPU versions.
If your dev work is CPU-intensive you should be doing it on a workstation or server anyways. A machine where your cooling solution can dissipate 3-400W without batting an eyelid is going to beat the crap out of a "high-end" 45W TDP laptop.
When you're on the road, just use SSH with tmux or RDP or whatever you prefer. At your desk, set up a monitor and a workstation for the serious work and keep the laptop on the side for meetings, emails etc. A USB switch for the mouse and keyboard works well and is like $30.