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Get Yaffs

Yaffs is available under the GNU General Public Licence, v.2  and under commercial terms.

For testing and experiment you can grab Yaffs under the GPL free of charge right now from our GIT repository and we strongly recommend you also read How Yaffs Works.

The GIT summary page shows the changes that have been made over time in the base code.


Yaffs is the property of Aleph One Limited.

Yaffs is available free of charge under the terms of the GNU General Public License version 2, GNU GPL2   given at:-

See especially Sections 3.a and 3.b.  These and the following sections describe the obligations placed on those who distribute source and/or object code embodying or associated with GPL code, and therefore apply to all who use Yaffs under GPL.

Linking Yaffs to other software creates a derived work and our interpretation of linking includes dynamic and runtime linking.  The derived work has the usual GPL obligation to release source code to anyone who asks. This remains true if you use Yaffs with another, or no, OS.

Commercial licensing

Aleph One, as owners of Yaffs, sell commercial Licences for the use of Yaffs which do NOT carry the obligations of GPL.

Contributing modifications of Yaffs code to the mainline code does not alter its Licence status.

Commercial Yaffs licences are non-exclusive, perpetual, world-wide, royalty-free and paid for with a single fee for one product. A commercial Licence entitles you to most further development and improvement of the Yaffs code.

The base price for a Licence for a single Product is GB£10,000. Sterling

You can find further information about Licences in these documents:

If you have any questions, or would like to buy a commercial licence, please contact us either at +44 (0)1223 811679 or email  or see our Contacts page:-

Other Downloads

You can use this Vagrant box to test Yaffs.

To run it you will need VirtualBox, which you can download from (50 to 90MB download). To run Virtualbox you will need a PC which is capable of virtualisation. Any PC made in the since about 2006 should be capable of this, apart from notepads, and even some notepads have virtualisation. 


This video shows you how to compile Yaffs into Linux. It’s just over 10 minutes long, and if you download it, it’s 325MB. After watching this video you should be able to include Yaffs in Linux.

This video covers the preparation needed to include Linux in Yaffs - describing the kernel build-tools needed, how to get the kernel source code and Yaffs source code. It's about 175Mb and 6m30 long.

This video from 2007 describes Yaffs1 and Yaffs2. The slides from the video are available.