The EUDIS Hackathon, a part of the EU Defence Innovation Scheme (EUDIS), is an outreach event that brings together people from various backgrounds to solve challenge. It was simultaneously held in six countries in a hybrid format: Belgium, Poland, Italy, Greece, Lithuania, and Hungary. The theme of this first edition was “Digital in Defence' and it centered on three challenges: improving situational awareness, subsea infrastructure protection, and cybersecurity in defence.