Superhero Battler Arena Hackathon

A three-hour competitive hackathon run by Barcelona's Java User Group at AI Campus Barcelona. You build an application that registers a squad of superheroes into a live tournament API, and the organisers run the battles. Teams form on arrival, then there is an introduction to the Arena API before the rounds start. Each round adds constraints such as squad limits or budget caps, and results stream live as the bracket advances. Any language or framework is allowed, a Java starter template is provided, and the API spec and docs are published in advance at superhero-battle-arena.barcelonajug.org so you can plan before you turn up. Vonage sponsors the prizes: a Keychron keyboard, an MX Master 3S and a gaming headset for the top three. Free, 18:00 to 21:00, RSVP on Meetup. Why go: a build-and-compete evening rather than slides, and explicitly open to students and junior developers. Best if you want a low-stakes way to ship something in three hours alongside other people.