# Mach Kernel **Domain:** Operating Systems / Microkernels **Doc Type:** Technical History Node **Maturity:** Historical **Primary Source:** [[articles/The Art is Long|The Art is Long: Vespucci of Immortality]] **Related:** [[wiki/NEXTSTEP|NEXTSTEP]], [[wiki/XNU|XNU]], [[wiki/NeXT|NeXT]] --- ## Definition **Mach** is an operating-system kernel architecture associated with message passing, task and thread abstractions, virtual memory, and the separation of system services. Mach-derived foundations were used in NeXT's operating systems and later incorporated into Apple's XNU kernel lineage. ## Corpus Context Mach is one of the architectural bridges connecting NeXT's scientific-workstation environment to the operating systems that later became mass-deployed consumer platforms. The lineage should be described precisely rather than reduced to the claim that NEXTSTEP simply became Darwin.