The current version of TeX is 3.1415926; it was last updated in March 2008. The design was frozen after version 3.0, and no new feature or fundamental change will be added, so all newer versions will contain only bug fixes. Even though Donald Knuth himself has suggested a few areas in which TeX could have been improved, he indicated that he firmly believes that having an unchanged system that will produce the same output now and in the future is more important than introducing new features. For this reason, he has stated that the “absolutely final change (to be made after my death)” will be to change the version number to π, at which point all remaining bugs will become features. Likewise, versions of METAFONT after 2.0 asymptotically approach e, and a similar change will be applied after Knuth’s death.
Wikipedia article on TeX versioning. By the way, Perl 6 milestones are numbered with 2 Pi decimal digits.
Oleg Andreev

Software designer with focus on user experience and security.
You may start with my selection of articles on Bitcoin.
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Product architect at Chain.
Author of Gitbox version control app.
Author of CoreBitcoin, a Bitcoin toolkit for Objective-C.
Author of BTCRuby, a Bitcoin toolkit for Ruby.
Former lead dev of FunGolf GPS, the best golfer's personal assistant.
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I am very interested in innovative ways to secure property and personal interactions: all the way from cryptography to user interfaces. I am not interested in trading, mining or building exchanges.
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