The best replacement for hal is udev.

The best alternatives to hal are rated as following:
★★★★★  udev
★★★★  walter
★★★★  slb
★★★  glados
★★★  celebrity
★★★  hateoas
★★★  siren
★★★  kyle
★★  homeseer
★★  json api
★★  ncl
★★  sinestro
★  hotspur
★  walt
★  hybrid assistive limb
★  mitchell being human
★  json-ld
★  walter white
★  dbus
★  direct3d hal
  acpi
  heisenberg
  hasl
  rccl

Your alternative for hal is not listed? Suggest!
Speaking about hal, one probably shouldn't forget about gnome.

Other search terms related to hal and their ratings are:
★★★★★ gnome
You have in mind a companion for hal and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of hal in all years. Click on graph for more.
hal
udev
walter