Hackathons, Builder Nights, office hours and Demo Days
Next up · Builder Night
Wed, 21 Oct 2026, 09:00 – Fri, 23 Oct 2026, 17:00 Athens War Museum, Athens, Greece
6th edition of CityJS in Athens: JavaScript and AI engineering conference. Workshops on 21–22 Oct at venues across Athens, main conference day 23 Oct at the Athens War Museum with 35+ talks across two tracks, plus a post-conference Sounio day trip on 24 Oct. Tech conference listed here as a community event.
Hackathon
Thu, 12 Nov 2026, 09:00 – Fri, 27 Nov 2026, 18:00 Athens (kick-off at Harokopio University, pitching at University of Piraeus, awards at AUEB)
Student hackathon by Netcompany, bringing students together with technology companies across Athens. Kick-off 12 Nov at Harokopio University, project submission deadline 20 Nov, pitching 26 Nov at the University of Piraeus, awards ceremony 27 Nov at AUEB. Prizes: €3,000 / €2,000 / €1,000. Registration closes 6 Nov 2026, 23:59. Times shown are placeholders; check the official page for the schedule.
Hackathon
Sat, 14 Nov 2026, 17:00 – Sun, 15 Nov 2026, 21:00 Athens, Greece
36-hour hackathon on the agentic AI frontier, run alongside the GenAI Summit South East Europe. Capacity 100–120 builders. Finalists are announced Sunday 21:00 and pitch on the Summit main stage on Monday 16 Nov. Prizes: €5,000 / €2,500 / €1,000, plus partner awards.
Builder Night
Mon, 16 Nov 2026, 09:00 – Mon, 16 Nov 2026, 18:00 Stavros Niarchos Foundation Cultural Center, Athens, Greece
5th GenAI Summit, a large generative AI conference in Athens powered by 100mentors. Demos, case studies, workshops and talks on agentic AI; hackathon finalists pitch on the main stage. Times are placeholders; check the official site for the programme.
Builder Night
Thu, 19 Nov 2026, 09:00 – Thu, 19 Nov 2026, 18:00 Thessaloniki, Greece
6th WMF Startup Competition & Conference by the Hellenic-Italian Chamber of Thessaloniki. 10 selected Greek startups pitch to business leaders, investors and angels; the top 3 go to the WeMakeFuture! Festival in Bologna (10–12 Jun 2027). Idea submissions closed 5 Nov 2026. Venue and times to be confirmed.
Builder Night
Fri, 20 Nov 2026, 09:00 – Sat, 21 Nov 2026, 18:00 DAIS Events Center, Marousi, Athens, Greece
Annual non-profit, volunteer-run technical conference of the Athens tech ecosystem. 2026 themes: AI-Native Engineering, Software Craftsmanship, Tech with Impact, plus cybersecurity and leadership. An Open Hackathon is also announced under the same Open Conf umbrella. Tech conference listed here as a community event.
Builder Night
Fri, 20 Nov 2026, 09:00 – Sat, 21 Nov 2026, 18:00 Ioannis Vellidis Convention Center, Thessaloniki, Greece
10th anniversary edition of the developer conference in Thessaloniki: 30+ sessions across 3 stages over two days, for developers, architects and engineers. Last edition drew 700+ attendees. Tech conference listed here as a community event.
Hackathon
Thu, 26 Nov 2026, 09:00 – Fri, 27 Nov 2026, 18:00 Athens, Greece
AI innovation competition for 18–35-year-olds, co-organised by the Athens Chamber's startup incubator (THEA) and Türkiye's Bilişim Vadisi. Semifinals in Athens 26–27 Nov; final and awards in Türkiye 3–4 Dec. Prizes: €20,000 / €10,000 / €5,000 plus 6 months of free incubation. Note: applications closed on 19 Sep 2026, so this is for following, not joining. Times are placeholders.
Builder Night
Fri, 11 Dec 2026, 09:00 – Sat, 12 Dec 2026, 18:00 War Museum, Athens, Greece
WordPress conference run by the Greek WordPress community, celebrating 10 years of WordCamp in Greece. Main stage in the 500-seat Ioannis Kapodistrias Auditorium. Tech conference listed here as a community event.
Hackathon
Fri, 19 Mar 2027, 09:00 – Sun, 21 Mar 2027, 18:00 LifeTech Park, Athens, Greece
Greece's largest AI hackathon, hosted by ACE (AUEB). Three days of workshops, keynotes, challenge presentations, hacking, mentoring and final pitches, ending with an awards ceremony. Apply solo or as a team; free for selected participants. Challenge and open tracks. Times are placeholders.
Builder Night
Tue, 25 May 2027, 09:00 – Tue, 25 May 2027, 18:00 Athens, Greece
One-day software testing, QA and UX conference by GRTB (the Greek ISTQB chapter), with about 900 participants and a QA & Quality Engineering track plus a UI/UX & Product Design track. Call for papers is open. Venue to be confirmed.
Builder Night
Wed, 26 May 2027, 09:00 – Fri, 28 May 2027, 23:00 Athens, Greece
Athens' tech, startup and culture festival, 26–28 May 2027, ending with a street party below the Acropolis. The 2026 edition had 10K attendees, 250+ speakers and 90+ side events including AI and life-sciences hackathons. The 2027 side-event lineup is not yet announced; pre-registration is open.