I kind of had the same idea, some time ago, and got an Asus T100 series with Bay Trail, 2 GB of RAM and 32 GB of flash. So it's one generation behind the devices you're talking about. The keyboard is detachable, so I can use the thing as a tablet.
Battery life is great -- no problem charging it overnight and not worrying about charging during the day.
In my case, I'm not a commercial developer, but I do "scientific programming" using primarily Jupyter/Python. It works comfortably on the little Windows 10 machine, but is noticeably slower.
Perhaps a bigger issue than horsepower for me is the screen size and attachment of the screen to the keyboard. Those things make it hard for me to spend long amounts of time doing really detailed or complicated stuff.
You can always adapt to lower processing power by using simpler tools, but trying to program on a 10" screen may end up being the main issue.
Have you considered getting something like a mobile beamer to get a bigger screen?
Particularly if the ultra-book is already HD capable.
Yes, it would require a "free" wall, but maybe that's OK.
A bigger problem might be power consumption.
So overall likely not very viable, but maybe someone has some experience with this?
Browsing is the one thing that seems fine. How does the lack of memory manifest itself? It may be due to my particular activities, but for more than two decades I've been aware of what is considered the minimum RAM for a developer system at any given time, and have gotten away with 1/2 to 1/4 of that amount, typically due to starting out with a cheaper system and then keeping it for a long time.
Using a cheaper system, if possible, is my "protection plan." I like to stay within what I could afford to replace out-of-pocket if something happens like the device gets stolen or I crash my bike.
But your point is well taken, and a developer should consider the typical system for their own preferred environment, which is likely to be more sophisticated than mine.
Battery life is great -- no problem charging it overnight and not worrying about charging during the day.
In my case, I'm not a commercial developer, but I do "scientific programming" using primarily Jupyter/Python. It works comfortably on the little Windows 10 machine, but is noticeably slower.
Perhaps a bigger issue than horsepower for me is the screen size and attachment of the screen to the keyboard. Those things make it hard for me to spend long amounts of time doing really detailed or complicated stuff.
You can always adapt to lower processing power by using simpler tools, but trying to program on a 10" screen may end up being the main issue.