Since 2022, it is possible to persons external to the Geant4 collaboration to contribute to the software along a model which is rather close to the open development one. The contributor rights and duties are similar to full Geant4 member ones, the main differences being in the size and complexity of the contributions -these are limited to relatively small additions and bug fixes, with no need for new expertise- and in the absence of duties regarding sharing the collaborative effort needed to maintain Geant4. If you plan large or advanced developments, you will be asked to become a full collaborator, with maintenance duties.
The advantage of becoming a contributor is to participate actively to the development of new functionalities or bug fixes, managing and monitoring directly the evolution of these. For bug fixes, this can considerably accelerate the process of verifying the effect of the fixes.
As anyone contributing to Geant4, your intellectual property is preserved.
The contributors have to well understand the specificities of Geant4 to not misuse this status. The key aspects are that physics developments:
- span over months, incrementally,
- can be experimental, hence with the possibility of being dismissed if appearing not adequate,
- require campaigns of validation, with careful examinations of the results, before being publicly released.
These specificities make that a snapshot of the master development tree taken at arbitrary time is not usable by default for physics studies. Becoming a contributor in the hope of benefiting from the daily most up-to-date version of Geant4 would then be a mistake and a serious misunderstanding of what this status is meant for.
Process to become ‘contributor’
To become a contributor, you have to contact the spokesperson, deputy spokesperson and Working Group coordinator in which you plan your contributions, explaining in a few lines what you intend to provide. The acceptance (or rejection), should come within a few working days.
To access the geant4dev GitLab repository, you need a full CERN account. The granting and creation of a CERN user account has to go through a formal procedure, which will take place along with the request acceptance and pending eligibility. Once setup, you can start working.
Commonalities and differences between ‘members’ and ‘contributors’
As for the commonalities, the contributors have to obey the rules governing the Collaboration. As for anyone accessing the geant4dev repository, a special point of attention is about the ongoing and not yet published works, often performed by young members, and which are of key importance for their career: these should not be imprudently exposed. Any publication of results on others’ work without their explicit consent on non-public releases or shortly after a public release is not allowed and would lead to immediate and permanent termination of the status.
The lighter status of contributor wrt the member one, induces the following differences:
- As said at the beginning, contributions should not be large, and should be maintainable by the existing members. If not the case, it then make more sense to become a full member, and otherwise your application could not be accepted.
- Contributors are free from maintenance duties, even though their help may be asked for bug fixes, for examples.
- Contributors do not attend by default the yearly Collaboration Meeting, even though they can attend by invitation by Working Group coordinator(s).