Complex user's needs often require heterogeneous services to be combined together. In this paper, we explore a novel approach to enable flexible and dynamic composition of heterogeneous services for end users who are usually not familiar with technical process models. End-users are only required to model their goals and semantic reasoning is used for the composition itself. The possible service compositions are expressed in BPMN in order to be then processed by a BPMN engine. Since the composition is built on-the-fly, this approach avoids static linking of services and therefore is much more flexible.

Requirements representation in agile methods is often done on the basis of User Stories (US) which are short sentences relating a WHO, WHAT and (possibly) WHY dimension. They are by nature very operational and simple to understand thus very efficient. Previous research allowed to build a unified model for US templates associating semantics to a set of keywords based on templates collected over the web and scientific literature. Since the semantic associated to these keywords is mostly issued of the i* framework we overview in this paper how to build a custom rationale diagram on the basis of a US set tagged using that unified template. The rationale diagram is strictly speaking not an i* strategic rationale diagram but uses parts of its constructs and visual notation to build various trees of relating US elements in a single project. Indeed, the benefits of editing such a rationale diagram is to identify depending US, identifying EPIC ones and group them around common Themes. The paper shows the feasibility of building the rationale diagram, then points to the use of these consistent sets of US for iteration content planning. To ensure the US set and the rationale diagram constitute a consistent and not concurrent whole, an integrated Computer-Aided Software Engineering (CASE) tool supports the approach.

The collaborative nature of software development helped in the emergence of several online collaborative software development platforms (CSDPs). These platforms enable distributed teams of contributors to participate in the development of the various hosted projects. In such a context, the identification of relevant contributors is very important for handling efficiently the abundant requirements. This is quite essential for achieving a successful requirements engineering process, and hence a successful software project. However, this can be really challenging because of the fairly large number of involved contributors, especially in some distinguished projects. Moreover, the contributor profiles on a CSDP are often inadequately informative, which makes them an unqualified resource for learning about the contributors. In this paper, we propose to identify contributors by their reputation on a CSDP. Our approach calculates reputation scores using a belief calculus, called subjective logic, according to contributors' performed roles. Knowing the reputation of anonymous contributors would enable project members to reduce the uncertainty in their future interactions with them. Moreover, we use concept lattices to classify contributors by their reputation scores, which enable us to have a comparable view on the considered contributors. Consequently, we can produce a roadmap to examine new requirements thus supporting their effective communication and prioritization.

Requirements engineering is an essential step of the software development process during which the behavior of a software system is defined. A lot of artifacts are created at this stage of the development process, and stakeholders need to be supported in managing requirements' consistency and evolution over time. In this paper, we present ArgRE, an argumentation-based system to be used by stakeholders to structure complex goal-based requirements, and maintain their consistency over time. In particular, we rely on meta-argumentation, where requirements are represented as arguments, and the standard Dung-like argumentation framework is extended with the relations holding among goal-based requirements.

The Web has given rise to several platforms serving the purpose of collaborative software development. Thanks to these environments, it is possible for anyone to suggest new requirements for a software under development. A lot of requirements are thus proposed by stakeholders and it becomes difficult, after a while, for the persons in charge of the software under development to take advantage of this large set of requirements.

In order to design workflows in changing and dynamic environments, a flexible, correct, and rapid realization of models of the activity flow is required. In particular, techniques are needed to design workflows capable of adapting themselves effectively when exceptional situations occur during process execution. The authors present an approach to flexible workflow design based on rules and patterns developed in the framework of the WIDE project. Rules allow a high degree of flexibility during workflow design by modeling exceptional aspects of the workflow separately from the main activity flow. Patterns model frequently occurring exceptional situations in a generalized way by providing the designer with skeletons of rules and suggestions about their instantiation, together with indications on relationships with other rules, with the activity flow, and with related information. Pattern based design relies on a pattern catalog containing patterns to be reused and on a formal basis for specializing and instantiating available patterns.