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There are several releases of the project. Please check maven repository for details.
Release 1.x - deprecated, migrate to 5.x.
Release 2.x - deprecated, migrate to 5.x.
Release 3.x - deprecated, migrate to 5.x.
Release 4.x - deprecated, abandoned branch on sonatype, migrate to 5.x.
Release 5.x - current stable stable, latest stable and maintained version.
Release 6.x - development, refactored branch of 5.x able to work with an alternate FDK structure, under development, new features and major changes on core.
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