What is Mirage OS?

MirageOS is a library operating system that constructs unikernels for secure, high-performance network applications across a variety of cloud computing and mobile platforms. The code can be developed on a normal OS such as Linux or MacOS X, and then compiled into a fully-standalone, specialized 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 uses the OCaml language, with libraries that provide networking, storage and concurrency support that work under Unix during development, but become operating system drivers when being compiled for production deployment. The framework is fully event-driven, with no support for preemptive threading.


Mirage OS follows a standard Github workflow and has its own Developer Portal. All developer-related information such as documentation, development team members, and other information related to the development of Mirage OS can be found there as well.


The Mirage codebase is released under the ISC license, with some portions of code released under LGPLv2.  Sub-Projects hosted by the Xen Project team typically use GPLv2. In the case of  Mirage, it is necessary to use a permissive open source license such as “ISC” because Mirage based microkernels need to be statically linked with applications to form a stand-alone appliance.