Grant: Discovery Grants Program - Individual

Software Magazine ranked the World's top 500 software companies in 2010: 20 were from Canada, the second-highest national percentage after the United States. Canada's information and communication technologies (ICT) sector include 37,400 companies, among which 33,000 develop software, employing hundreds of thousands of developers to develop and maintain these systems. Conservative studies estimate that 80% of the developer's time and effort are invested in maintenance. Hence, any improvement to the maintainability of systems could results in important gains in time, effort, and, thus, cost reduction. Maintainability remains an elusive characteristic of software systems and software quality models measuring maintainability are difficult to build and apply on different systems. Indeed, quality models are currently under-developed. There are three reasons for these difficulties: (1) each software system is unique, thus a model built for one system often does not apply on another, (2) modern systems often combine different programming paradigms, e.g., object-oriented and functional, thus, lowering their maintainability and complexifying the building of quality models, and (3) the sub-characteristics of maintainability are ill-defined, thus models are defined partially, using proxy measures, often excluding many aspects of the systems. Aspects of the systems include implementation idioms, design choices, architecture styles, user-observable features, internal and external APIs, and used frameworks and libraries. I propose to tackle these difficulties (1) by considering more aspects of the systems and (2) by considering “classes” of systems. Building on my previous and current research work, I will consider features and application programming interfaces (APIs) that provide similar services and that can be found in different systems with different implementations, designs, architectures, and frameworks implemented in different combinations of programming languages. I will use similar services, e.g., undo/redo, as a starting point to study software systems in “classes” and not as unique individual. I will also use features, APIs, metrics, and occurrences of design (anti)patterns to build software quality models focusing on maintainability of multi-language, multi-paradigm systems. I will evaluate these models on large, multi-language, multi-paradigm systems, like Mozilla Firefox or SFL Ring. I will perform three types of validations: (1) quantitatively and qualitatively through (2) developers' studies (with participants) and (3) social studies (e.g., surveys). Thus, I want to contribute to advance our understanding of the aspects of software systems impacting their maintainability and provide developers with concrete, useful means to measure this maintainability so that they can improve it and, thus, can reduce maintenance costs.