I use as few external libraries as possible, most things are implemented from scratch. Most libraries don't fit the programming model the XADMaster framework uses anyway.
Anyway, the problem is that there are two formats called ".lzma" - the one implemented by the old LZMA-utils, and the new one implemented only by beta LZMA-utils, which was then turned into XZ. However, several formats seem to have adopted the beta LZMA-utils format, and now I don't know if that is the same as what XZ ended up being or not.
To make it more confusing, it seems XAR supported BOTH the old and new LZMA formats under the same name, so does it now have a THIRD lzma format with a new name?