High-integrity systems are critical, complex software-controlled systems in contexts where the occurrence of failure can severely affect the environment, organization, and/or society. Examples are typically found among safety-critical and mission-critical systems. Typical high-integrity systems are highly hardware-dependant; hence, the rapid rate of hardware technology evolution in these systems demands the development of software systems that keep up with the hardware infrastructure. This necessitates the existence of elaborate software development methodologies which accommodate the volatility of the environment, and properly address the critical features required of the system under development.
To develop software development methodologies that are appropriate for high-integrity systems development, different approaches have been adopted; some are based on modifying existing methodologies – focusing on those processes which are capable of accommodating criticality and flexibility, such as XP and SCRUM - and tailoring them to the specific requirements of high-integrity systems; others focus on models and modeling as the primary means of software development, and prescribe methods for seamless transformation and refinement of models to one another until the final product is obtained.
The main objective of this research is to develop a framework for the engineering of software methodologies suitable for the construction of high-integrity systems. To this aim, an analytical survey on high-integrity software development methodologies is conducted to highlight the important features and characteristics of critical systems, and to identify methods, practices and techniques for implementing these features. The outcome of this phase is then integrated into a coherent Situational Method Engineering (SME) framework which serves as a substrate for the construction of high-integrity-systems development methodologies. To verify the validity of the proposed framework, it will be applied in the context of a small-scale SME project.