11 - 12 June 2025 | Brussels, Belgium

ProjectathonOnce-Only Technical System Projectathon #6

A marathon of peer-to-peer interoperability and compliance tests in a structured environment

Registrations for this Projectathon are closed. If you would still like to attend, please contact the organisers under EC-OOTS@ec.europa.eu(opens in a new tab)

Gallery

Experience the event in its entirety and relive every moment with our gallery.

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Practical information

Location

Conference Center Albert Borschette (CCAB)
Rue Froissart 36
1040 Brussels, Belgium
Date

11 - 12 June 2025. In addition, 10 June is foreseen as a preparatory “Day 0” to test the setup or perform readiness checks and 13 June as a travel day.
Registration

Registrations for this Projectathon are closed. If you would still like to attend, please contact the organisers under EC-OOTS@ec.europa.eu(opens in a new tab)
Target groups

All Member State teams relevant for implementing the Once-Only Technical System as well as representatives from national competent authorities.
Fees

No fees are charged to participate in this event.
Travel

The Commission can cover the reimbursement of travel costs of up to four participants in total per Member State: up to two from the national team and up to two competent authorities representatives, vouched by their respective national coordinator.

Description

What is this event about?

This is a large-scale testing event that allows different Member State systems to connect under one roof and perform a marathon of peer-to-peer interoperability and compliance tests in a structured environment. In parallel to testing, two exploration tracks (workshops) will allow competent authorities and implementation teams to explore specific topics related to the Once-Only Technical System.

This Projectathon will be of thematic nature, to enable evidence exchange between national competent authorities in specific domains. It will focus on population, education and business data. In addition, this Projectathon will foster the on-going collaboration with related systems.

When will this event take place?

It will take place from 11 to 12 June 2025. In addition to these days, the participants are invited to join an optional “Day 0” on 10 June to prepare their setup and receive support from the Commission. As the testing activities during this Projectathon are condensed to two full days, the participants are strongly encouraged to stay until 17:00 on Day 2 (12 June) and travel home later in the evening of that day or on 13 June.

Who is this event for?

This Projectathon is open to all Member State teams, regardless of the maturity of their Once-Only implementation. The Commission also highly encourages competent authorities to attend.

What are the benefits of joining this event?

This Projectathon will allow national implementation teams to perform peer-to-peer and compliance tests over two days. The Commission will provide support to Member States that are (nearly) production-ready to enable end-to-end transactions, while assisting those catching up to enhance their technical readiness. In addition, national teams will be able to participate in ‘exploration tracks’, i.e. workshops focusing on specific topics related to the OOTS. This event will also allow participants to discuss more advanced scenarios in dedicated exploration sessions or in a restricted test session between teams interested in such scenarios.

In addition, competent authorities can benefit from joining the exploration tracks. These workshops will, for example, delve into telling compelling narratives around Once-Only, discuss the Once-Only Evidence Explorer and Common Services, and explore next steps towards exchanging structured data. These workshops will also be a unique chance for competent authorities to meet and connect with experts from all over Europe. In addition, competent authorities will have the chance to participate in or observe the end-to-end transactions of production-ready Member States.

How can you participate?

You can register for this event through EU Survey from 15 April to 6 May.

How to access the test cases

A high-level overview and summary of current test cases is available to the Testing and deployment sub-group (restricted access)(opens in a new tab).

The full test cases with detailed step-by-step descriptions will be made accessible later via the Gazelle platform (restricted access)(opens in a new tab).

Download the privacy statement

Projectathon agenda

Conference Centre Albert Borschette (CCAB)
Rue Froissart 36, 1040 Etterbeek.
See on Google Maps(opens in a new tab)
10:00 - 12:00

Setup, readiness checks and/or custom support in preparation of the Projectathon
13:00 - 17:00

Continued: Setup, readiness checks and/or custom support in preparation of the Projectathon

Conference Centre Albert Borschette (CCAB)
Rue Froissart 36, 1040 Etterbeek.

See on Google Maps(opens in a new tab)

Room 2.C Room 2.D
08:00 - 09:00

Welcome coffee & registration
09:00 - 09:15

Welcome to the #6 Once-Only Technical System Projectathon (Day 1)
09:15 - 09:45

High-level keynote to open the #6 OOTS Projectathon – Jakub Boratynski, Director (and acting Head of Unit), DG GROW, European Commission
09:45 - 10:00

Introduction to the Once-Only Technical System Projectathon
10:00 - 12:00

Technical set-up and initial tests
12:00 - 13:00

Lunch
13:00 - 14:30

Peer-to-peer testing – Part 1
14:30 - 15:00

Coffee break
15:00 - 16:30

Peer-to-peer testing – Part 2
16:30 - 17:00

Wrap-up of the day + introduction to next day

Spaces
Rue Belliard 40, 1040 Etterbeek.
See on Google Maps(opens in a new tab)
18:00 - 21:00

Informal dinner and networking event including welcome from Natalia Aristimuño Pérez, Director, DG DIGIT, European Commission

Conference Centre Albert Borschette (CCAB)
Rue Froissart 36, 1040 Etterbeek.

See on Google Maps(opens in a new tab)

Room 2.C Room 2.D
08:30 - 09:00

Welcome coffee
09:00 - 09:30

Introduction to the Once-Only Technical System Projectathon (Day 2)
09:30 - 12:00

Peer-to-peer testing – Part 1
12:00 - 13:00

Lunch
13:00 - 14:30

Peer-to-peer testing – Part 2
14:30 - 15:00

Coffee break
15:00 - 16:30

Peer-to-peer testing – Part 3
16:30 - 17:00

State of play of June 2025 Projectathon

Exploration rooms

During this Projectathon, two exploration room tracks will run in parallel. Participants can join session from both tracks.

Conference Centre Albert Borschette (CCAB)
Rue Froissart 36, 1040 Etterbeek.

See on Google Maps(opens in a new tab)
Room 2.B
10:00 - 12:00

Technical Design Documents: Release 1.2.0 and beyond, including related systems updates if applicable

In this session we will provide an overview of some advanced functionalities in TDDs, including new functionalities introduced in version 1.2, which is less well-known, implemented and tested. This session will also provide an overview of existing cross-border systems related to SDG procedures and the OOTS and explore the potential to use "technical bridges" to interconnect.

Audience: OOTS experts and implementers, including and especially those not active in the TDD subgroup; OOTS implementers and competent authorities from domains where related systems are used.
13:00 - 14:30

SMP and Technical Support Dashboard

This information session will explore the latest SMP and Technical Support Dashboard updates.

Audience: OOTS architects, technical and operational teams.
15:00 - 16:30

OOTS matching of cross-border identities and evidences

The goal of this session is to collect input from the participants on the topic of identity and evidence matching performed by evidence providers or intermediary platforms (Article 16 of COMMISSION IMPLEMENTING REGULATION (EU) 2022/1463). This input will be further used for the creation of a more detailed section on this topic in the Technical Design Documents.

The participants are expected to actively participate in this session, by either presenting their current solution or sharing lessons learnt and challenges on this topic.

Audience: Anyone interested is welcome to join, but please be prepared to actively contribute.

Conference Centre Albert Borschette (CCAB)
Rue Froissart 36, 1040 Etterbeek.

See on Google Maps(opens in a new tab)
Room 2.B
10:00 - 12:00

Synergies between the OOTS and the EUDI Wallet: Final report of the Contact Group and presentation by the Association of NL Municipalities on its PoC to provide data simultaneously to the OOTS and the EUDI Wallet

During this meeting, the Commission will present the Final Report: UX Synergies and Investment synergies. The session will feature a discussion on the reports’ main conclusions and way forward. Afterwards, the Association of Netherlands Municipalities (VNG) will present a proof-of-concept to provide data simultaneously to the OOTS and the EUDI Wallet.

Audience: Contact Group Representatives as well as interested OOTS experts and eIDAS expert group members outside the Contact Group.
13:00 - 14:30

Communications and onboarding

This session will include Nathalie Van Raemdonck (PhD candidate), who is conducting interviews and focus groups on operational issues faced by competent authorities. These findings will shape a 2026 onboarding roadmap. Additionally, this session will feature a lookout to future (local) events.

Audience: Anyone communicating about the OOTS and/or onboarding CAs is welcome to join.

This session takes place on-site only.
15:00 - 16:30

Overcoming language barriers (joint session for tracks 1 and 2)

This session will focus on the current functionalities related to the use of natural language in the OOTS. Afterwards, it will discuss the use of multilingual forms, structured data with coded content, and the possibility to integrate translation.

Audience: OOTS community at large.

Conference Centre Albert Borschette (CCAB)
Rue Froissart 36, 1040 Etterbeek.

See on Google Maps(opens in a new tab)
Room 3.C
10:00 - 11:30

OOTS stories: Developing compelling narratives around Once-Only

During this session, we'll look back on the Eureka programme's achievements and look to the potential of storytelling for the OOTS' future.

Audience: Anyone interested is welcome to join.
13:00 - 14:30

Evidence Mapping: Workshopping the approach

In this session we will workshop the approach to evidence mapping by building on the on-going discussions within the subgroup. The first part of the workshop will discuss the underlying principles and deep-dive into Member States contexts to better understand the challenges with the proposed approach and then we’ll discuss ways to adapt or refine the approach to overcome them.

Audience: National coordinators, subgroup representatives and competent authorities (evidence requesters & providers).
15:00 - 16:30

Common Services and Evidence Explorer: Latest developments and future plans

This session will build on the evidence mapping workshop. We will examine how changes to the evidence mapping approach would affect the Common Services. Participants are asked to bring their computers so that they can interact with prototype screens themselves.

Audience: National coordinators and competent authorities (evidence requesters & providers).

Conference Centre Albert Borschette (CCAB)
Rue Froissart 36, 1040 Etterbeek.

See on Google Maps(opens in a new tab)
Room 3.C
10:00 - 12:00

OOTS data models: Next steps towards exchanging structured data

This session will discuss implementation strategies and challenges faced by Member States, with the aim of refining the governance of data models and update protocols on the OOTS side.

Audience: National coordinators and competent authorities adopting structured data.
13:00 - 14:30

UX lab updates: Latest research and implementation best practices

In this session we will perform peer-to-peer usability tests. Participants are asked to bring a computer and a link to their latest prototype or live-OOTS service so it can be tested by a colleague from another Member State. With the support of a usability checklist, you will be able to give and get valuable feedback and identify opportunities for to improve the OOTS experience for end-users.

Audience: National coordinators, UX Designers and competent authorities adopting structured data.

This session takes place on-site only.
15:00 - 16:30

Overcoming language barriers (joint session for tracks 1 and 2)

You can find details on this session in track 1 (joint session for tracks 1 and 2).

Exploration rooms

More information on the agenda of the exploration rooms will be available soon.

Perform Peer-to-Peer tests

1
Search potential Test Partner through Gazelle
2
Meet Test Partner and schedule test
3
Execute Tests and upload evidence in Gazelle
4
Monitors examine evidence and evaluate test result
5
Fix bugs (if any)

How to register for the June 2025 Once-Only Technical System Projectathon

1
Information: Attend the OOTS Implementers’ Café #14 on 15 April 2025.
2
Registration: The registration period runs from 15 April to 6 May 2025.
Fill-in the event registration form (via EU survey) and accept to have read and understood the content of the Projectathon Playbook and Privacy Statement. It is mandatory for every participant of a Member State to fill in the event registration form (it is a pre-condition for getting access to the Gazelle platform). Participants and observers must register for each individual Projectathon. Please register on time, this is also needed for the catering.
3
The OOTS Support Team will send a confirmation email to you once your registration to the Projectathon is accepted. We will get in contact with you as from 22 April 2025 with more information about how to register and create your SUT in the Gazelle platform. Since 2024, Gazelle data has been anonymised, you will have to register again in 2025 and create your SUT according to the new modelisation.
4
Register the system and participants in Gazelle: In case you need test related data for archiving or auditing purposes, don’t forget to archive your data in Gazelle at the end of the year since data will be again anonymised and will be deleted one month after the end of the year (around end of January 2026).
5
If not already done, register to the Microsoft Teams Implementers Space(opens in a new tab) via the Service Desk(opens in a new tab). This Teams channel is made available for everyone that registers and participates to the Projectathon to facilitate knowledge-sharing and closer collaboration.