With the rise of cloud computing and the migration to web-based applications, scalable systems have become highly desirable. And while developing software is hard, designing a scalable system is even harder. The microservice architecture is an attempt to improve the scalability but may introduce additional challenges. In order to correctly implement the microservice architecture, it is important to understand how the different mechanisms used in the architecture affect the quality of the application. The purpose of this research is to show how to evaluate microservice applications and how much they can differentiate from each other. A literature study and an architectural analysis are performed by reviewing research related to web applications and microservices. Subsequently, the empirical data is collected by evaluating and comparing two different microservice applications based on their quality characteristics. The results of the literature study indicate that performance efficiency, compatibility, reliability, security, maintainability and portability are the most relevant quality characteristics of the microservice architecture. Furthermore, the architectural analysis describes how microservices affect these quality characteristics. Lastly, the evaluation showed that different approaches can significantly alter the strength of the different characteristics. For this specific comparison between the two selected applications, it was determined that the biggest differentiating factor is the asynchronous and synchronous messaging. To conclude, the results show it is possible to evaluate a microservice application by its qualities. Additionally, while microservice applications may use completely different technologies, the fundamental concept behind them remains the same. What differs is the approaches used and how they affect the quality characteristics.

Most of the process measurement studies are related with time and cost based models. Although quality is the other conventional aspect, there are no widely used models for measuring the process quality in the literature. In order to provide complementary information about the quality, a process quality measurement model has been chosen to be developed and the studies about process characteristics have been searched in the scope of the thesis. Moreover, by utilizing the similarities between process and software, the studies in software quality have been investigated. In the light of the researches, a model is built on the basis of ISO/IEC 9126 Software Product Quality Model. Some of the quality attributes are redefined in the model according to the process characteristics. In addition, new attributes unique only to the process are developed. A case study is performed and its results discussed from different perspectives of applicability, understandability and suitability.