Josef "Jeff" Sipek <>

If you would like to contact me about any of my code/ideas/etc., you have two main choices...
Then there is always my blahg.


Currently, I am an engineer at Open-Xchange working on Dovecot.

Previously, I was an engineer at Nexenta Systems (2014-2016). Before that, I was an engineer at Barracuda Networks (2011-2014).

I was an PhD student in Computer Science and Engineering at the University of Michigan (until April 2011, M.S. only), and a B.S. student in Computer Science at Stony Brook University (until December 2007).

While at the University of Michigan, I worked with Peter Honeyman on I/O performance of systems and with Jason Flinn on distributed filesystem metadata caching on flash-based solid state drives. And while at Stony Brook in the File system and Storage Lab (under the guidance of Prof. Erez Zadok), I worked on Unionfs (a stackable namespace unification filesystem) and FiST: Stackable File System Language and Templates.


My programming languages of choice are C (but not C++) and shell scripting. I'm a fan of Mercurial for source code management.

Current projects

Past projects

The following few projects are either obsolete (due to the underlying tools not being available), or just not actively maintained due to lack of time. Let me know if you want to take over the maintenance of any of them.


Publications & Workshops

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