Setting up biber as a default biblatex backend in the configuration file

Question

The biblatex release notes recommend to setup backend=biber in biblatex.cfg, however LaTeX refuses to accept this text in biblatex.cfg:

\ProvidesFile{biblatex.cfg}
\usepackage[backend=biber]{biblatex}
\endinput

LaTeX says, "The package biblatex has already been loaded with options..."

How to set up backend parameter in here properly?

Answer 1

Load biblatex in your main document using \usepackage[<options>]{biblatex}. Your configuration file biblatex.cfg should look as follows:

\ProvidesFile{biblatex.cfg}
\ExecuteBibliographyOptions{backend=biber}
\endinput

UPDATE: As Jonathan has hinted, with biblatex v2.0 (released July 2012) backend has become a loadtime option, so it is not possible anymore to select the backend engine (biber, BibTeX etc.) via \ExecuteBibliographyOptions. Also note that biber (not BibTeX) is now the default backend.