Building on the results achieved in the previous workshops and subsequent discussions, the present workshop aims at continuing to develop the OPTiMaDe API. The latter will greatly benefit the materials science community (e.g. by enhancing opportunities for data mining) and clearly contribute to fostering innovation. Furthermore, it will aid the validation and verification of the codes and the theories, which has become increasingly important in the field .
To this end, we propose to gather all the key developers involved in the different efforts, both from Europe and the US. The workshop would obviously include some oral presentations about the different DBs and their latest capabilities. But, the largest fraction of the time would be dedicated to more technical presentations and discussions about the first implementations of the OPTiMaDe API. We also propose to leave more than 10 hours for a coding party continuing to implement the API. Despite the large efforts that have been put in the development of open databases for materials design, their integration is clearly lacking.
The previous two workshops have contributed to creating a community involved in the development of the OPTiMaDe API. A website has been set up  with a mailing list, a wiki, and a GitHub repository. Thanks to the discussions (that have taken place during the workshops and through the mailing list), a first version (v.0.9.5) of the OPTiMaDe API has been released . During the last meeting, revisions and extensions have been debated and a new version of the specification is being finalized (a paper will also be published).
The proposed workshop will continue the current efforts and contribute to implementing the OPTiMaDe API on as many DBs as possible.