About this role
<div><div style="padding:10.0px 0.0px;border:1.0px solid transparent"><div style="font-size:16.0px;word-wrap:break-word"><H2 style="font-size:1.0em;margin:0.0px"><b>Teaser Text</b></H2> </div><div><p style="margin-top:0.0pt;margin-bottom:7.0pt;font-family:arial;font-size:10.0pt">Applications are invited for a fully funded three-year postdoctoral position aimed at the intersection of theoretical computer science, computer systems, and security. The topic of the research will be centered on applying techniques from automata theory and programming language semantics within program similarity detection, with applications to recurrent vulnerability detection, as well as optimizing compilers, with a focus on code specialization and abstraction. This is a unique position that involves skills both in theory and software implementation.</p> <p style="margin-top:0.0pt;margin-bottom:7.0pt;font-family:arial;font-size:10.0pt">In more detail, programming language theory commonly uses automata to describe the behavior of a program from an operational point of view; in systems, control flow graphs can be seen as a different approach to the same principle, used to reason about (among other matters) compiler optimization. In this project, we will investigate theoretical methods to represent control flow graphs as automata and subsequently apply these novel methods in the domains of computer systems as well as security. Within computer systems, we wish to investigate more relaxed implementations of function merging based on bisimulation. In security, we will use these theoretical foundations to develop code equivalence and similarity detection methods, possibly using SMT-based techniques.</p> <p style="margin-top:0.0pt;margin-bottom:7.0pt;font-family:Calibri;font-size:11.0pt"> </p> <p style="margin-top:0.0pt;margin-bottom:7.0pt;font-family:arial;font-size:10.0pt">Key publications:</p> <ul style="margin-top:0.0in;margin-bottom:0.0in" type="disc"> <li style="margin-top:0.0pt;margin-bottom:7.0pt;vertical-align:middle"><span style="font-style:italic;font-family:arial;font-size:10.0pt">Outrunning Big KATs: Efficient Decision Procedures for Variants of GKAT.</span><span style="font-family:arial;font-size:10.0pt"> Cheng Zhang, Qiancheng Fu, Hang Ji, Ines Santacruz Del Valle, Alexandra Silva, Marco Gaboardi; </span><a href="https://doi.org/10.1007/978-3-032-22723-2_14"><span style="font-family:arial;font-size:10.0pt">https://doi.org/10.1007/978-3-032-22723-2_14</span></a></li> <li style="margin-top:0.0pt;margin-bottom:7.0pt;vertical-align:middle"><span style="font-style:italic;font-family:arial;font-size:10.0pt">CF-GKAT: Efficient Validation of Control-Flow Transformations.</span><span style="font-family:arial;font-size:10.0pt"> Cheng Zhang, Tobias Kappé, David E. Narváez, Nico Naus; </span><a href="https://doi.org/10.1145/3704857"><span style="font-family:arial;font-size:10.0pt">https://doi.org/10.1145/3704857</span></a></li> <li style="margin-top:0.0pt;margin-bottom:7.0pt;vertical-align:middle"><span style="font-style:italic;font-family:arial;font-size:10.0pt">Eradicating the Unseen: Detecting, Exploiting, and Remediating a Path Traversal Vulnerability across GitHub</span><span style="font-family:arial;font-size:10.0pt">. Jafar Akhoundali, Hamidreza Hamidi, Kristian F. D. Rietveld, and Olga Gadyatskaya; </span><a href="https://doi.org/10.1145/3708821.3736220"><span style="font-family:arial;font-size:10.0pt">https://doi.org/10.1145/3708821.3736220</span></a></li> <li style="margin-top:0.0pt;margin-bottom:7.0pt;vertical-align:middle"><span style="font-style:italic;font-family:arial;font-size:10.0pt">Function Merging by Sequence Alignment</span><span style="font-family:arial;font-size:10.0pt">. Rodrigo C. O. Rocha, Pavlos Petoumenos, Zheng Wang, Murray Cole, and Hugh Leather; </span><a href="https://doi.org/10.1109/CGO.2019.8661174"><span style="font-family:arial;font-size:10.0pt">https://doi.org/10.1109/CGO.2019.8661174</span></a></li> </ul></div></div><div style="padding:10.0px 0.0px;border:1.0px solid transparent"><div style="font-size:16.0px;word-wrap:break-word"><H2 style="font-size:1.0em;margin:0.0px"><b>What you will do</b></H2> </div><div><ul style="margin-bottom:0.0cm;margin-top:0.0px"> <li style="line-height:normal;margin:0.0cm 0.0cm 0.0cm 0.0px;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt"><strong>Develop theory</strong> aimed at applying concepts around bisimilarity to control flow graphs, with an eye towards applications in compiler engineering and security;</span></li> <li style="line-height:normal;margin:0.0cm 0.0cm 0.0cm 0.0px;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt"><strong>Design algorithms</strong> to put this theory to work for its intended application, along with the necessary optimizations to achieve a feasible runtime;</span></li> <li style="line-height:normal;margin:0.0cm 0.0cm 8.0pt 0.0px;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt"><strong>Implement and benchmark</strong> those algorithms, to develop push-button solutions that can be applied to real-world source and binary code today;</span></li> <li style="line-height:normal;margin:0.0cm 0.0cm 8.0pt 0.0px;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt"><strong>Publish</strong> your research findings in top-tier conferences, and <strong>present</strong> your work at conferences, contributing to the scientific community's body of knowledge;</span></li> <li style="line-height:normal;margin:0.0cm 0.0cm 8.0pt 0.0px;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt"><strong>Get involved</strong> with LIACS as a whole, for instance by co-supervising student theses, taking place in committees, or assisting in teaching – the exact responsibilities here depend on your preferences.<br><br></span> <p style="margin:0.0cm 0.0cm 7.0pt;line-height:115%;font-size:12.0pt;font-family:Calibri, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">You will be a member of both the <em>Theory</em> and <em>Systems & Security</em> clusters at LIACS, and supervised by Tobias Kappé (Theory), Kristian Rietveld and Olga Gadyatskaya (both Systems & Security).</span></p> </li> </ul></div></div><div style="padding:10.0px 0.0px;border:1.0px solid transparent"><div style="font-size:16.0px;word-wrap:break-word"><H2 style="font-size:1.0em;margin:0.0px"><b>Where you will work</b></H2> </div><div><p style="line-height:normal;margin:0.0cm 0.0cm 10.0pt;font-size:11.0pt;font-family:Calibri, sans-serif;text-align:left"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">The Faculty of Science is a world-class faculty where staff and students work together in a dynamic international environment. It is a faculty where personal and academic development are top priorities. Our people are committed to expand fundamental knowledge by curiosity and to look beyond the borders of their own discipline; their aim is to benefit science, and to contribute to addressing the major societal challenges of the future. The research carried out at the Faculty of Science is very diverse, ranging from mathematics, information science, astronomy, physics, chemistry and bio-pharmaceutical sciences to biology and environmental sciences. The research activities are organised in eight institutes. These institutes offer eight bachelor’s and twelve master’s programmes. The faculty has grown strongly in recent years and now has more than 2.300 staff and almost 5,000 students. We are located at the heart of Leiden’s Bio Science Park, one of Europe’s biggest science parks, where university and business life come together. <span style="color:#222222">For more information, see </span><a href="http://www.universiteitleiden.nl/en/science"><span style="color:#0070c0">www.universiteitleiden.nl/en/science</span></a> and <a href="http://workingat.leiden.edu/"><span style="color:#0070c0">http://workingat.leiden.edu/</span></a><br>The Leiden Institute of Advanced Computer Science (<strong>LIACS</strong>) is the Artificial Intelligence and Computer Science Institute in the Faculty of Science of Leiden University. We offer courses at the Bachelor and Master of Science level in Artificial Intelligence, Computer Science, ICT in Business, Media Technology, and Bioinformatics. According to an independent research visitation, we are one of the foremost computer science departments of the Netherlands. We strive for excellence in a caring institute, where excellence, fun, and diversity go hand in hand. We offer a clear and inviting career path to young and talented scientists with the ambition to grow. For more information about LIACS, see <a href="http://www.cs.leiden.edu"><span style="color:#0070c0">http://www.cs.leiden.edu</span></a></span></p></div></div><div style="padding:10.0px 0.0px;border:1.0px solid transparent"><div style="font-size:16.0px;word-wrap:break-word"><H2 style="font-size:1.0em;margin:0.0px"><b>What you bring</b></H2> </div><div><p style="line-height:normal;margin:0.0cm 0.0cm 8.0pt;font-size:12.0pt;font-family:Calibri, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">We are looking for candidates who fit the following criteria.</span></p> <ul style="margin-top:0.0cm;margin-bottom:0.0cm" type="disc"> <li style="line-height:normal;margin-top:0.0cm;margin-right:0.0cm;margin-bottom:8.0pt;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">In possession of a PhD or are in the last stretch of their PhD program;</span></li> <li style="line-height:normal;margin-top:0.0cm;margin-right:0.0cm;margin-bottom:8.0pt;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">Have published work in either theoretical topics (such as automata theory, decision procedures, programming language semantics, verification) or systems and security (e.g., automated vulnerability detection, compilers);</span></li> <li style="line-height:normal;margin-top:0.0cm;margin-right:0.0cm;margin-bottom:8.0pt;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">Curious to develop their theory-oriented expertise with research applied to systems and security, or vice versa, add more theory-oriented skills to a portfolio centered around systems or security research;</span></li> <li style="line-height:normal;margin-top:0.0cm;margin-right:0.0cm;margin-bottom:8.0pt;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">Having experience developing and optimizing non-trivial software projects; experience using LLVM and/or AST libraries is preferred;</span></li> <li style="line-height:normal;margin-top:0.0cm;margin-right:0.0cm;margin-bottom:8.0pt;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">Would enjoy developing and benchmarking proof-of-concept implementations of new algorithms and methodologies developed over the course of the research;</span></li> <li style="line-height:normal;margin-top:0.0cm;margin-right:0.0cm;margin-bottom:8.0pt;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">Eager to aim for publication at top-tier conferences such as CCS, USENIX Security, CAV, and PLDI;</span></li> <li style="line-height:normal;margin-top:0.0cm;margin-right:0.0cm;margin-bottom:8.0pt;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">Available to start quickly; the preferred starting date is September 1, 2026, or as soon as possible thereafter.</span></li> </ul></div></div><div style="padding:10.0px 0.0px;border:1.0px solid transparent"><div style="font-size:16.0px;word-wrap:break-word"><H2 style="font-size:1.0em;margin:0.0px"><b>What we offer</b></H2> </div><div><div> <ul style="margin-bottom:0.0cm;margin-top:0.0px"> <li style="line-height:normal;margin:0.0cm 0.0cm 0.0cm 0.0px;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">An employment contract for a duration of one year. After a positive evaluation of the progress of the research, personal capabilities and compatibility, the appointment will be extended by two more years;</span></li> <li style="line-height:normal;margin:0.0cm 0.0cm 0.0cm 0.0px;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">Salary ranges from €3.546,- to €5.538,- gross per month (38 hours, pay scale 10) in accordance with the Collective Labour Agreement for Dutch Universities and will be commensurate with the candidate’s level of experience;</span></li> <li style="line-height:normal;margin:0.0cm 0.0cm 0.0cm 0.0px;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">Leiden University offers an attractive benefit package with additional holiday allowance (8%), end-of-year bonuses (8.3 %), a pension scheme at ABP, training and career development and sabbatical leave. Our individual choices model provides you with flexibility to assemble your own set of terms and conditions;</span></li> <li style="line-height:normal;margin:0.0cm 0.0cm 0.0cm 0.0px;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">The option of working from home one day a week;</span></li> <li style="line-height:normal;margin:0.0cm 0.0cm 0.0cm 0.0px;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">A work-from-home allowance (day and internet allowance) and attention to good workplaces (the university will also provide you with a laptop);</span></li> <li style="line-height:normal;margin:0.0cm 0.0cm 0.0cm 0.0px;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">Funding to attend conferences where work will be published;</span></li> <li style="line-height:normal;margin:0.0cm 0.0cm 0.0cm 0.0px;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">A collegial work environment within a growing research institute;</span></li> <li style="line-height:normal;margin:0.0cm 0.0cm 8.0pt 0.0px;font-size:10.0pt;font-family:arial, helvetica, sans-serif"><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">A possibility to further enhance academic career opportunities by, for example, developing relevant skills in student supervision (from BSc to PhD), teaching (including pursuing a BKO), or research project acquisition and management.</span></li> </ul> </div> <p> </p></div></div><div style="padding:10.0px 0.0px;border:1.0px solid transparent"><div style="font-size:16.0px;word-wrap:break-word"><H2 style="font-size:1.0em;margin:0.0px"><b>What we value</b></H2> </div><div><p><span style="font-family:arial, helvetica, sans-serif;font-size:10.0pt">Promoting an inclusive community is central to Leiden University’s values and vision. We strive to be an open community in which all students and staff members feel valued and respected, and are able to fully develop themselves. We consider an inclusive academic environment, where students and staff can share their experiences and viewpoints, to be essential for the development of talent.</span></p></div></div><div style="padding:10.0px 0.0px;border:1.0px solid transparent"><div style="font-size:16.0px;word-wrap:break-word"><H2 style="font-size:1.0em;margin:0.0px"><b>Want to apply or find out more?</b></H2> </div><div><div><span style="font-family:arial;font-size:10.0pt">If you have questions about this position, please contact Dr. Tobias Kappé (</span><span style="font-family:arial;font-size:10.0pt">[email protected]</span><span style="font-family:arial;font-size:10.0pt">), Dr. Kristian Rietveld (</span><span style="font-family:arial;font-size:10.0pt">[email protected]</span><span style="font-family:arial;font-size:10.0pt">) or Dr. Olga Gadyatskaya (</span><span style="font-family:arial;font-size:10.0pt">[email protected]</span><span style="font-family:arial;font-size:10.0pt">). If you have questions about the procedure you can send an email to: </span><span style="font-family:arial;font-size:10.0pt">[email protected]</span> <p style="margin-top:0.0pt;margin-bottom:8.0pt;font-family:arial;font-size:10.0pt"><br>Are you interested in this vacancy? Please submit your application online. Please ensure that you upload the following additional documents in English:</p> <ul style="margin-top:0.0in;margin-bottom:0.0in" type="disc"> <li style="margin-top:0.0;margin-bottom:0.0;vertical-align:middle"><span style="font-family:arial;font-size:10.0pt">A letter touching on all of the following topics: </span></li> <ul style="margin-top:0.0in;margin-bottom:0.0in" type="circle"> <li style="margin-top:0.0;margin-bottom:0.0;vertical-align:middle"><span style="font-family:arial;font-size:10.0pt">your motivation to apply to this position in particular</span></li> <li style="margin-top:0.0;margin-bottom:0.0;vertical-align:middle"><span style="font-family:arial;font-size:10.0pt">prior research experience in theory, systems or security; and</span></li> <li style="margin-top:0.0;margin-bottom:0.0;vertical-align:middle"><span style="font-family:arial;font-size:10.0pt">your experience in research-centered software development.</span></li> </ul> <li style="margin-top:0.0;margin-bottom:0.0;vertical-align:middle"><span style="font-family:arial;font-size:10.0pt">A short curriculum vitae;</span></li> <li style="margin-top:0.0;margin-bottom:0.0;vertical-align:middle"><span style="font-family:arial;font-size:10.0pt">A list of your publications;</span></li> <li style="margin-top:0.0pt;margin-bottom:8.0pt;vertical-align:middle"><span style="font-family:arial;font-size:10.0pt">Names and contact details of at least two academic references.</span></li> </ul> <p style="margin-top:0.0pt;margin-bottom:8.0pt;font-family:Calibri;font-size:12.0pt"> </p> <p style="margin-top:0.0pt;margin-bottom:8.0pt;font-family:arial;font-size:10.0pt;color:black"><span style="font-weight:bold">Please note: We are seeking to find the right colleague as soon as possible, so applications will be evaluated as they arrive. If you are interested in this position, we encourage you to apply at your earliest convenience.</span></p> <p style="margin-top:0.0pt;margin-bottom:8.0pt;font-family:Calibri;font-size:11.0pt"> </p> <p style="margin-top:0.0pt;margin-bottom:8.0pt;font-family:arial;font-size:10.0pt">The preferred starting date is <span style="font-weight:bold">September 1, 2026 (negotiable)</span>. This vacancy will automatically close on <span style="font-weight:bold">August 31, 2026</span>. </p> </div></div></div></div>