During an ongoing argument in a chatroom between some folks about how “zomg systemd is ruining everything”, I decided to look at some init system history. I learned a cool tidbit of information from a HN comment1: apparently systemd’s design was inspired by Apple’s launchd. Embarassingly, I knew little to nothing about launchd, even as a lifelong Mac user. I began to play with launchctl on my local machine. Turns out that launchd does some pretty cool things: the *.plist describing a job can do more than just specify its arguments. For example, the QueueDirectories key lets you spawn jobs when files are added to a directory (how useful!). I was oblivious to this having interacted with launchd the past years mostly via brew services. With the help of soma-zone’s LaunchControl and launchd.info companion site, I was able to fiddle and figure out what various plist keys did.

The Apple IIgs came out on September 15, 1986. It featured a 2.8 MHz WDC 65816 CPU (the same one that powered the SNES and other similar computers of that era, a 16-bit CPU with 24-bit addressing), 256k or 1MB RAM (upgradable to 8 MB), and an Ensoniq 8-bit stereo synth (which was a welcome upgrade from the bit-speaker of the Apple II family). For reference, the original Apple II family was built around the 6502 CPU (8 bit, 16-bit addressing), and had at most 1 MB of RAM in the IIe and II+. However, it was not until 1988 that Apple had released an operating system for the new computer that was able to meaningfully leverage the newer hardware. GS/OS was written in native 16-bit code, and more importantly, was intended to be used via its new shiny GUI.