Biotech > FAQ > BioPerl FAQ (Frequently Asked Questions)

What is the difference between 1.5.1 and 1.4.0? ...

To see other biotech frequently asked questions, please visit

(Continued from previous question...)

What is the difference between 1.5.1 and 1.4.0? What do you mean developer release?

The 1.4.x series was released in 2004 and represented a stable release series. The 1.5.0 release was made in early 2005 but several annoying bugs were included in it. The 1.5.1 release in October has fixed those bugs and also added a number of new modules as well. See the Changes file for more information.

Developer releases are odd numbered releases (1.3, 1.5, etc) not intended to be completely stable (although all tests should pass). Stable releases are even numbered (1.0, 1.2, 1.6) and intended to provide a stable API so that modules will continue to respect the API throught a stable release series. We cannot guarantee that APIs are stable between releases (i.e. 1.6 may not be completely compatible with scripts written for 1.4), but we endeavor to keep the API stable so that upgrading is easy.

(historical text from old FAQ)

0.7.X series (0.7.0, 0.7.2) were all released in 2001 and were stable releases on 0.7 branch. This means they had a set of functionality that is maintained throughout (no experimental modules) and were guaranteed to have all tests and subsequent bug fix releases with the 0.7 designation would not have any API changes.
The 0.9.X series was our first attempt at releasing so called developer releases. These are snapshots of the actively developed code that at a minimum pass all our tests.

(Continued on next question...)

Other Frequently Asked Questions