  FEniCSx Preconditioning Tools (FEniCSx-pctools) is a software package for
easing the specification of PETSc-based block preconditioning strategies in the
DOLFINx finite element solver of the FEniCS Project. It attaches all of the
necessary metadata to the block-structured linear systems in order that
block-structured preconditioners can be applied straightforwardly via PETSc's
options-based configuration system. Fast prototyping is facilitated thanks to
the implementation in Python, and all intensive operations are executed in
C/C++. FEniCSx-pctools is available under the LGPLv3 or later license.
