exhibition

During her inaugural lecture in 2018, Prof. Marieke Huisman argued that ‘software is everywhere’. Examples that she gives pertain to the railroad infrastructure, medical apparatus, webshops, and many more. Indeed, computers have changed our lives fundamentally. Yet, as Marieke rightfully observes, this also means that small software mistakes can have negative consequences that are not any less fundamental – vast, costly, and sometimes even fatal. For instance, in 1962, NASA launched the first-ever space probe to collect scientific data from Venus. Sadly, the Mariner I - as it was called - had to be destroyed shortly after lift-off. It appeared that the omission of a hyphen-shaped symbol in the code had caused the entire software system to become unreliable. In his 1968 book, The Promise of Space, Science-fiction author Arthur C. Clarke described the omission as “the most expensive hyphen in history”. More disastrous, radiation dosage software used in Panama City in 2000 allowed massive overdoses for some patients battling cancer. Reporting on the case, journalist John McCormick warns that “applications must be fool proof, and that - whether embedded in the engine of a car, a robotic arm in a factory or a healing device in a hospital - poorly deployed code can kill”.
Marieke would agree. The creation of reliable software is at the heart of her interest in computer science. Essentially, Marieke argues that software programs require a formal delineation akin to the blueprint of a house. The metaphor goes as follows. By describing the construction of a house in terms of a blueprint, the engineer can reason on its expectations and identify possible construction errors prior to its realization. In other words, the blueprint allows the engineer to verify their calculations even before they have laid the first brick. Likewise, expressing software in terms of formal logic can help to ‘reason’ on it; to identify coding errors even before the software program had been deployed in practice. Especially the latter seems important, to which the Mariner I and the Panamanian radiation shields are an unfortunate testimony.
In the 1990s, Marieke and her peers were one of the first to introduce ‘program verification programs’: software programs that can help to translate pieces of code into logical descriptions effectively and efficiently. In this regard, Marieke developed the LOOP Compiler during her PhD at the Radboud University, Netherlands, applying program verification to Java. Once completed, Marieke continued to work on program verification at the INRIA Sophia Antipolis, France, where she applied verification to Java Bytecode and envisioned doing the same with concurrent, multithreaded programs. Multithreaded programs conduct multiple calculations at the same time, which may not only influence each other but also share memory. This makes it difficult to predict the behaviour of the software program; to verify beforehand whether the program is going to do what was expected from it. Today, Marieke continues her research into program verification at the University of Twente as a Professor in Software Reliability. Here, she dedicates herself to the ongoing development of the VerCors toolset, which can help to apply program verification to different types of software in a relatively easy way.
In 2013, Marieke received the Dutch ICT Prize for her merits in computer science. Aside from her academic endeavours, Marieke has been Chair at the Dutch National Association for Software Engineering for three years and has been Chair in the Equity, Diversity, and Inclusion working group at ICT Research Platform Netherlands since 2020. Since 2017, Marieke is also chairperson of the Ambassadors’ network at the University of Twente. Here, she focuses on diversity and inclusiveness. Diversity leads to creativity, she explains, and creativity leads to better software. In this respect, McCormick’s warning is a good reminder that better software may be expressed not just in terms of efficiency and effectiveness, but also in terms of safety. Marieke’s mission is a laudable one: “Software Reliability for Everyone!”