Conferences are great opportunities for sharing research, debating solutions, and networking. For the organizing committee there is a considerable deal of complexity and effort required to provide attendees and organizers with ways to find and manage programs, sessions, papers, tracks, talks, and authors. Eelco Visser found an opportunity to provide an integrated solution to these problems by designing the Conf Researchr conference management system in 2014 using our own domain-specific web programming language WebDSL. In this paper, we highlight the impact Eelco had on conference management, and how Conf Researchr evolved to become the platform of choice for hosting over 900 conference and workshop editions in SIGPLAN and SIGSOFT, among other areas of computer science research.

SDF, Stratego and Spoofax provide a platform for development of domain-specific programming languages. On this platform, the WebDSL project started out as a case study in language engineering, and grew into a reliable tool for rapid prototyping and continuous development of web applications. Our team led by Eelco Visser develops and operates several web applications to support academic workflows. EvaTool governs the process of course quality control, importing questionnaire data, and providing lecturers and education directors with a platform to discuss and agree on improvements. WebLab is an online learning management system with a focus on programming education, with support for lab work and digital exams, used by over 40 courses. Conf Researchr is a domain-specific content management system for creating and hosting integrated websites for conferences with multiple co-located events, used by all ACM SIGPLAN and SIGSOFT conferences. MyStudyPlanning is an application for composition of individual study programs by students and verification of those programs by the exam board, used by multiple faculties at the Delft University of Technology. These tools served as practical case studies for applying the research, and ensure the continued development of the underlying platform.

Web applications are ideal for implementing information systems; they can organize and persist the data in a database, do not require installation on client machines, and can be instantly updated everywhere. However, web programming is complex due to its heterogeneous nature, causing web frameworks to suffer from insufficient or leaky abstraction, weak static consistency checking, and security features that are not enforced. We developed the WebDSL web programming language, which supports direct expression of intent, strong static consistency checking, linguistic abstractions for web programming concerns, and automatically enforces security features for web applications. We have used WebDSL for over 10 years to create information systems for academic workflows with thousands of users. Based on our experiences with these applications, we improved the WebDSL compiler and runtime to increase robustness, performance, and security of applications. In this experience report, we reflect on the lessons learned and improvements made to the language runtime.

To provide empirical evidence to what extent migration of business logic to an incremental computing language (ICL) is useful, we report on a case study on a learning management system. Our contribution is to analyze a real-life project, how migrating business logic to an ICL affects information system validatability, performance, and development effort.
We find that the migrated code has better validatability; it is straightforward to establish that a program ‘does the right thing’. Moreover, the performance is better than the previous hand-written incremental computing solution. The effort spent on modeling business logic is reduced, but integrating that logic in the application and tuning performance takes considerable effort. Thus, the ICL separates the concerns of business logic and performance, but does not reduce effort.