This charter motivates and describes the operating rules of the international working conference on variability modelling of software-intensive systems (VaMoS). It serves as a guide for open and transparent management of the event.

Goals and Spirit

VaMoS is a venue to discuss breakthroughs and experiences — academic or industrial — about variability-aware modelling techniques and their applications to software-intensive systems. VaMoS started in 2007 as a workshop and became a working conference in 2020. Over the years, it developed a “community spirit”. The following words best define this spirit: discussion and openness. VaMoS is intrinsically discussion-oriented, and its schedule reflects this orientation. For example, there is a single track to allow everyone to participate in all sessions. At the end of each paper presentation, one or more discussants — who read the paper in advance — give their insights and invite the audience to engage in the Q/A session. VaMoS is also fundamentally open. It welcomes new fields of variability-intensive research, such as artificial intelligence, hybrid software-hardware systems, etc. VaMoS also welcomes newcomers in the variability community, either junior researchers (MSc and PhD students) or more experienced researchers coming from other fields and discovering variability research, given the ubiquity of variability in software-intensive systems nowadays.

Steering Committee

The VaMoS steering committee (SC) monitors the organization of the VaMoS conference series and supports the VaMoS community in the long term. 

SC chairs

SC chairs organize regular meetings (at least twice a year) to discuss important points. These points naturally include selecting upcoming venues for VaMoS, for which we aim to have two-year visibility. The venue for the next edition is announced at the end of the current edition. Besides, SC chairs invite the organizers of the past edition to report on and identify successes and attention points as part of a continuous improvement process. The SC discusses these major points to drive the future. SC chairs also initiate evolutions of the current charter if needed. 

There are two SC chairs. 

Finance Chair

To keep track of the former editions (by maintaining a website) and providing information/resources to the VaMoS community (composition of the current SC, news, etc.).  We need some funding (essentially to maintain the domain and hosting costs).  The Finance chair acts as treasurer in this respect.

Steering Committee

Steering committee members participate in meetings (which can be online or physical at the conference), engage in discussions, and vote on all major decisions. They also serve as long-term ambassadors of the conference by submitting papers and attending the conference series as much as possible.

SC Recruitment Rule

The SC consists of previous organisers of the conference. The SC chairs invite two members among PCs and GC of the former conference edition to the SC. Under exceptional circumstances and after a vote of the SC, we may allow all three (PCs + GC) to enter the SC. Conversely, if fewer than two members are joining, the invitees can nominate one or two replacement members.

SC Replacement Rule

A lively SC entails a turnaround within its members. The following rules apply:

  • SC chairs: The SC chairs’ term is three years. The SC can reelect SC chairs for one additional term;
  • Finance chair: To ensure financial consistency, there is no automatic replacement rule for the finance chair. A Finance chair wishing to step down contacts the SC chairs. The SC chairs will then initiate a procedure for the replacement;
  • SC members: SC member period is five years.

General Chairs and Programme Chairs

For a given edition of the conference, there are (up to) two General chairs and two Program chairs. We recap their non-exhaustive duties here.

General Chairs (GCs)

Before the conference, GCs will submit a proposal to host a VaMoS edition to the SC, with tentative names for the team, notably PC chairs. If the SC accepts their proposition,  then the GCs become responsible for the local organisation.  This includes booking a conference location (if the conference is physical/hybrid), virtualisation infrastructure, appointing a Finance chair for a given edition to handle financial aspects, etc. They also ensure smooth operation during the event.

Programme Chairs (PCs)

PCs are responsible for the scientific programme of the conference. Thus, they select the technical programme committee (TPC) members and establish the programme based on the reviews. They also handle the publication process with ACM (they can designate a Publication chair if they wish to), which means registering the conference well in advance to ACM, processing camera-ready papers and copyright management.

Tip for selecting PCs: The selected PCs should not be too close (in terms of collaboration and co-authorship) to avoid having both chairs with a conflict of interest for the decision on a paper.

Other Chairs (OCs)

The GCs and PCs are free to designate other chairs for a given conference edition.  This includes for example Publicity chairs, Publication chairs (handling the ACM publication workflow), Finance chairs or any role they feel is helpful for the organisation.

Replacement Rule

GCs, OCs, and PCs change for every edition of the conference. It is possible to serve in a role for non-consecutive terms (with a gap of at least 5 years) or to alternate between GC and PCs two years in a row.

Technical Programme Committee (TPC)


TPC members warrant the scientific quality of the conference by providing fair, high-quality reviews and constructive feedback. These reviews are crucial to maintain community openness and encourage early-stage researchers to move forward.

TPC members are expected to:

  • advertise the conference in their networks;
  • submit one or more paper(s) to the conference (optional but encouraged);
  • bid on papers they wish to review;
  • review (typically) 2-4 papers;
  • take part in online discussions (this is extremely important in the VaMoS process);
  • vote for awards if it concerns the papers they reviewed;
  • attend the conference, either physically or remotely (depending on the organisation).


PCs choose TPC members regarding their scientific or industrial relevance concerning the scope of the conference. PCs should seek diversity amongst TPC members in terms of the research topics (variability is broad and covers all application domains), country of affiliation, gender, seniority, and academic/industrial balance. The TPC also includes the PCs of the previous edition (if they are not already in the TPC). Researchers publishing in VaMoS for several years in a row could be awarded an invitation to become part of the TPC.

The PCs set the TPC size to have a reasonable reviewing load (2-4 papers as mentioned above). Since the number of submissions of VaMoS is generally in the 20-30 papers range, this induces that the size of the TPC should belong to the 30-40 members range.  

Replacement Rule

There are reasons to vary TPC members to keep engagement and diversity during the reviewing effort. For example, some members may not have sufficient availability to provide high-quality reviews and focus their research on other domains. In such cases, we encourage invited members to decline the invitation and the PCs will be grateful for that. There might be other (hopefully extremely rare) cases where the TPC member is not up to the high standards of reviewing expected and enjoyed by the VaMoS community. In such duly justified cases, a TPC member can be replaced. On the other hand, strongly committed TPC members over a long period would suffer from a TPC membership age limit. We suggest renewing 10% of the TPC each year, at the discretion of the PC.

Conflicts of Interest

Since VaMoS publications are published by the ACM, VaMoS follows the general conflict of interest policy of the ACM:

A conflict of interest (CoI) denotes any situation where someone’s judgement is affected by a relationship with the judged person. This can be: 1) family relationship (spouse, children, etc.) 2) lifelong relationship between a PhD student and supervisor, 3) co-authorship within the last two years, 4) working at the same institution. The website above provides a more comprehensive list.

In particular, the following rules apply:

  1. PCs cannot submit papers to the edition of the conference they are chairing; 
  2. TPC members declare a CoI with papers (naturally including their own) during bidding. They notify the PCs immediately if a CoI arises when they receive their assignment.
  3. A PC having a CoI for one or more papers should delegate the discussion to the other PC. If both PCs have a CoI for a paper (this is normally limited due to the selection of PCs), they can, in such circumstances, delegate a TPC member to lead the discussion.

Tip for PCs: While it could be tempting to enact PCs’ CoI in the submission system (VaMoS currently uses Easychair), it is problematic as submissions disappear from the PCs’ view and may prevent sending all notifications. Therefore the SC trusts the PCs’ integrity to apply rule 3 above.

Conference Location

VaMoS has European roots and the SC prefers locations in Europe because this is where most of the community resides. There can be, and there have been exceptions. Such exceptions should be duly motivated to ensure the event’s accessibility for the European community and demonstrate its potential to attract submissions. Yet, we recall that VaMoS is open to all researchers and generally should accommodate when possible different time zones for those following the conference remotely.

A note on physical/hybrid/online mode. The COVID-19 pandemic greatly affected how we organise and engage in conferences by organising them all online. On the one hand, an online event has the advantage of welcoming more researchers from all over the world who could not usually join because of the lack of funds for travelling, VISA restrictions or a will to limit their carbon footprint. On the other hand, the community atmosphere is hard to maintain entirely online, as one cannot reproduce casual in-person interactions.

The SC acknowledges that motivating arguments for online and physical events are equally valid. Therefore, it recommends offering a hybrid organisation if possible.


VaMoS is an open-minded, inclusive and professional community. Under no circumstances a participant can harass another one on the grounds of gender, sexual orientation, ethnicity etc. Examples can be found in the ACM policy for harassment:

If a participant is harassed by another one, they can report to the GCs and PCs to make the harassment cease immediately. The harasser will be challenged. If the harassment persists, the participant will be excluded from the event and may be removed from any role (TPC, SC) they may have in the conference.


March 2021: Initial Draft
August 2021: First Version
December 2022: Version 1.0 for Approval