I am reminded of Andrew Tanenbaum's Minix os: before Linux became the belle of the ball, minix implemented many unix functionalities in a less efficient but cle

I am reminded of Andrew Tanenbaum's Minix os: before Linux became the belle of the ball, minix implemented many unix functionalities in a less efficient but clearer way than existing unix builds (many of which were not open source) and the still nascent bsd/linux/gnuos/etc, and it meshed nicely with his textbooks on OS design. It was functional on it's own, and by Minix 3 was a full os in it's own right (Intel still uses it in various ways) but balanced pedagogy with performance. https://en.wikipedia.org/wiki/Minix https://en.wikipedia.org/wiki/Minix gives more details.