Software development could be said to be declarative, if declarative programming languages were used significantly in the development of a software system. Software development could also be said to be declarative, if lightweight or heavyweight formal methods or model-driven engineering and model transformation were used as the primary development methods. This tutorial discusses another view on ‘declarative software development’. That is, we promote the use of declarative methods for understanding software systems, software languages, software technologies, and software concepts. More specifically, we discuss a method package of a software ontology, automated software analysis, a modeling approach for software technologies, and Linked Data-based publication and exploration of software data.