The feature list of modern integrated development environments is steadily growing and mastering these tools becomes more and more demanding, especially for novice programmers.Despite their remarkable capabilities, development environments often still cannot directly answer the questions that arise during program maintenance tasks. Instead developers have to map their questions to multiple concrete queries that can be answered only by combining several tools and examining the output of each of them manually to distill an appropriate answer. Existing approaches have in common that they are either limited to a set of predefined, hardcoded questions, or that they require to learn a specific query language only suitable for that limited purpose.We present a framework to query for information about a software system using a quasi-natural language interface that requires almost zero learning effort. Our approach is tightly woven into the Eclipse development environment and allows developers to answer questions related to source code, development history, or bug and issue management. For that, we model data extracted from various software repositories by means of ontologies, store them in a knowledge base of software evolution facts, and use knowledge processing techniques from the Semantic Web to query the knowledge base.Our approach was evaluated in a user study with 35 subjects, who had to solve various software evolution tasks for an industrial-scale, open-source software system. The results of our user study showed that our query interface can outperform classical software engineering tools in terms of correctness, while yielding significant time savings to its users and greatly advancing the state of the art in terms of usability and learnability.