Speaking of microkernels, MINIX 3 is open source, unlike the version of MINIX that inspired Linus to write Linux. MINIX 3, unlike earlier versions, aims to be

Speaking of microkernels, MINIX 3 is open source, unlike the version of MINIX that inspired Linus to write Linux. MINIX 3, unlike earlier versions, aims to be used in production rather than being purely a research OS. MINIX 3 has incorporated code from NetBSD making it possible to run a lot of software on MINIX 3 from the NetBSD ports collection. I have not used MINIX but I remain interested in it and think it deserves a mention.