What are the functionalities/solutions that are under current development in SIESTA?
SIESTA is in continuous development since it was implemented in 2002.
Several Functionalities and methods are under development, being implemented within the SIESTA code or as post-processing tool, within the project SIESTA-PRO (http://simune.wpengine.com/siesta-pro/). For example, the implementation of hybrid functionals, GW approximation, Band unfolding…
A complete list of Blueprint for SIESTA can be found here (https://blueprints.launchpad.net/siesta).