I create wrapper scripts. I try to keep them simple... they're convenience scripts, not a replacement for a build system.

Here's one for a QEMU dev env where I add and remove bits of command line in a freeform way. I just break out the command line into components, and uncomment the ones I want for a particular use:

  #!/bin/bash
  
  set -ex
  
  # Drive created with:
  # /usr/bin/qemu-img create -f qcow2  ngx.qcow2 40G
  
  #vga='-vga cirrus'
  vga='-vga std'
  #vga='-vga qxl'
  
  drive='-drive file=ngx.qcow2,cache=writeback'
  
  tablet='-usbdevice tablet'
  
  #vnc='-vnc :3'
  
  #cdrom="-cdrom base_install.iso"
  #cdrom='-cdrom documentation.iso'
  #cdrom="-cdrom /dev/sr0"
  cdrom=''
  
  #net='-net user -net nic'
  net='-net user,restrict=off,hostfwd=tcp::6666-:6666 -net nic,model=rtl8139,macaddr=00:11:82:C3:54:55'
  #net='-net user,restrict=on,hostfwd=tcp::6666-:6666,hostfwd=tcp::3389-:3389,hostfwd=udp::3389-:3389 -net nic,model=rtl8139,macaddr=00:11:82:C3:54:55'
  
  monitor='-monitor stdio'
  
  qemu-system-x86_64 -enable-kvm -nodefaults -m 768 $vga $drive $tablet $vnc $cdrom $net $monitor

If you have multiple stages to your build/run process, you can chain together a few scripts. build-and-run.sh builds it, and then calls run.sh which runs it. If you want to skip the build step, you use run.sh.