Resumen
Management of competencies is a crucial concern for both learners and workers as well as for training institutions and companies. For the former, it allows users to track and certify the acquired skills to apply for positions; for the latter, it enables better organisation of business processes. However, currently, most software systems for competency management adopted by the industry are either organisation-centric or centralised: that is, they either lock-in students and employees wishing to export their competencies elsewhere, or they require users? trust and for users to give up privacy (to store their personal data) while being prone to faults. In this paper, we propose a user-centric, fully decentralised competency management system enabling verifiable, secure, and robust management of competencies digitalised as Open Badges via notarization on a public blockchain. This way, whoever acquires the competence or achievement retains full control over it and can disclose his/her own digital certifications only when needed and to the extent required, migrate them across storage platforms, and let anyone verify the integrity and validity of such certifications independently of any centralised organisation. The proposed solution is based on C-Box®, an existing application for the management of digital competencies that has been improved to fully support models, standards, and technologies of the so-called Web 3.0 vision?a global effort by major web organisations to ?give the web back to the people?, pushing for maximum decentralisation of control and user-centric data ownership.