MirageOS is a library operating system that constructs unikernels for secure, high-performance network applications across a variety of cloud computing and mobile platforms. Code can be developed on a normal OS such as Linux or macOS, and then compiled into a fully-standalone, specialised unikernel that runs under a Xen or KVM hypervisor. This lets your services run more efficiently, securely and with finer control than with a full conventional software stack.

MirageOS applications take a few milliseconds to start-up instead of the few minutes that traditional OSes take. Binaries are self-contained: they do not need an additional OS to execute. Even then, the size of MirageOS binary is usually a few megabytes.

MirageOS applications are written in OCaml, an industrial strength programming language supporting functional, imperative and object-oriented styles.