Techniques and Practices for Software Architecture Work in Agile Software Development

Since the publishing of Agile Manifesto in 2001, the agile software development has taken the world by storm. Agile software development does not emphasize the importance of software architecture, even though software architecture is often seen as a key factor for achieving the quality goals set for the software system. It has been even said that agile software development and software architecture are a clash of two cultures.In many software projects there is no need to consider software architecture anymore. For example, when designing a mobile application, the ecosystem forces the developer to use certain architecture style provided by the platform. In web development ready-made frameworks and project templates are available offering complete software architecture designs for the application developer.There are still domains and systems where careful architecture design is needed. When developing complex systems or systems with a long lifecycle, diligent software architecture design is a key to avoid massive rework during the development. It cannot be a coincidence that companies developing these kinds of systems struggle with agile software development the most.On the one hand, the goal of this thesis was to study software architecture practices used in agile software development in the industry. On the other hand, the goal was to develop new methods and techniques to support incremental software architecture working practices which can be aligned with agile methods such as Scrum. The study applied case study, interviews and design science as the main research methods.The results show that there are four main ways to carry out software architecture work while using agile methods. Basing on this result, models for aligning software architec-ture knowledge management were developed. These models can be used as guidelines for selecting the appropriate software architecture practices in an organization.As a part of the research work, an architecture knowledge repository was developed for sharing the knowledge in agile projects and for automatic software architecture document generation. Additionally, the results of this study show that by taking a decision-centric approach to software architecture evaluation, the evaluation method can be lightweight enough to make incremental evaluation a viable option. Similarly, existing software architecture evaluation methods can be boosted to fit agile software development by utilizing domain knowledge