This is free software under both the Eclipse Public License and the GNU LGPL licence developed at CRIL. The SAT4J project is kindly hosted on the OW2 forge.
SAT4J is a library continuously evolving. However, it is now more than two years old and the code related to SAT solvers is now quite stable. The pseudo boolean part still needs some improvements. We do our best to avoid breaking the public API, so evolving to the latest version of the library should not require any change in the client code.
In you use SAT4J in your application, it would be nice to drop us an email.
The download area for official releases is now managed on ObjectWeb.
You can find on this web site the latest nightly build. Use it at your own risk! Check first the regression tests. If everything looks ok, you can download either a self executable jar file or the build source file. If you are modifying the source code of SAT4J, you should consider using the CVS repository.