QEM[2][3] & write shell script with option to a) "compile latest source & run the just compiled OS under QEM emulation" OR b) run known working OS under qem with development environment/tools for messing with source used in part a.
Advantage: on same box, one window can be the development environment. other QEM can compile/run in different window to test what was done via development environment. aka edit english paper in word processor & save. view/print the compiled results in different window.
grub / uboot[1] would be what pc hardware bios would use in place of the above QEM shell/boot script.