Paris tech events this week: OpenAI at STATION F, and a co-founder café on Friday

La rentrée is supposed to begin in September. The Paris tech events calendar has decided otherwise. Our listings for 28 August to 3 September hold exactly two things — both free — and between them they cover the entire arc of starting a company: the Friday afternoon you decide to, and the Thursday you actually build something. OpenAI is running one of them at STATION F. Entrepreneurs First is running the other out of its own office.

Two listings is not the Paris calendar; it is the part of it we have mapped so far. We opened the city on anopenroom recently, and August is the hardest month in France to take an honest reading of anything — so treat this as a hand-built first pass. Two rooms, properly, rather than ten in passing.

The big one: OpenAI's AI Privacy Hackathon lands at STATION F

The OpenAI AI Privacy Hackathon runs on Thursday 3 September, 09:30 to 20:00, at STATION F, and it is free. One long day, one theme: prototyping at the intersection of AI and privacy.

Three things make it the most significant item on the Paris calendar in weeks. OpenAI chose a build day rather than a keynote — the room gets judged on what comes out of it, which changes who bothers to turn up. The venue is not incidental: STATION F is the largest startup campus in the world, so a hackathon held there pulls in resident founders and accelerator cohorts as well as the people who registered. And privacy is the sharpest seam in European AI right now. This is the city of the CNIL, where data protection gets argued as a matter of principle rather than compliance overhead, with a research community that holds strong views on federated learning and on-device inference. Putting this hackathon here is not a neutral choice of postcode.

Come with a specific problem to attack — a model you cannot ship because of where the data sits, an anonymisation approach you have never had a clear day to test. That beats arriving to see what happens.

Friday first: tbc(afé) opens the Entrepreneurs First office

Before all that, there is a Friday. tbc(afé) Paris runs on Friday 28 August, 2pm to 5pm, free, at the Entrepreneurs First Paris office — address confirmed when you register.

EF and The Bridge are turning the office into a temporary work-and-co-founder café. Drop-in format: bring a laptop, work on your own thing, talk to whoever is at the next table. What makes it unusual is the guest list it implies. Entrepreneurs First backs individuals before there is a company, so a café in that office on a Friday afternoon is not a generic co-working session — it is a filtered room of engineers and operators who want to start something now rather than someday. If you have been circling the idea of leaving your job, this is the cheapest way to test how it sounds out loud.

Who should go where

Founders and founders-in-waiting — Friday, without hesitation. Pre-idea and pre-team is exactly the state tbc(afé) is built for, and a small late-August room serves that better than a packed September one.

Builders — Thursday 3 September. If you write code that touches personal data, this is the one day this fortnight when a full room is on your problem. Free, and you leave with something that runs.

Investors — a quiet week, honestly; neither event is structured for dealflow. If you want signal rather than meetings, STATION F is a decent read on which privacy-adjacent teams are forming before the autumn.

Sales and marketing — sit this one out. Both are working rooms, and neither rewards a pipeline target. September's afterworks are yours.

Last week, briefly

August was livelier than Paris's reputation allows. The Paris Tech Mixer & Social held its Friday slot at Hide Pub Club on 21 August (EUR 3). On Monday 24 August, AI FIRST ran The AI Builders Meetup #6 at Le Bar de L'Empire Hotel — free, in French, pointedly about getting from theory to working prototypes. Then on Thursday 27 August the Global Tech Hackathon Paris 2026 — EMCIS opened at Paris Ynov Campus alongside the EMCIS information-systems conference.

What that means for this week: the hackathon habit is established before la rentrée proper. Thursday at STATION F continues it rather than starting it.

Worth knowing

• The OpenAI hackathon is a full day: 09:30 to 20:00. Clear the whole Thursday rather than dropping in after lunch — a build day rewards the people who are there when teams form.
• tbc(afé)'s address is only released on registration. Sign up before Friday — you will not find the door otherwise.
• The Friday Tech Mixer has no 28 August edition on our listings. It ran every Friday through the summer, so this may be our gap rather than a pause. If it is on, tell us and we will list it.
• AI FIRST's AI Builders series runs in French. The next one, #7, is already on our pages for 7 September.

Already on the September page

The calendar is refilling faster than a two-event week suggests. Beyond AI Builders #7, the 4th Paris Hardware Meetup — Hardware Built for Space is listed for 8 September, with product, design and AI-marketing evenings following in mid-month.

Two events is a thin listing and we will not dress it up. But this is the stage where readers decide what our Paris coverage becomes: if you run an afterwork, a meetup, a workshop or a demo night here and it is not on our pages, send it over — one email does more for the next edition than anything we can scrape. Everything live is on the Paris listings page.