Applications are invited for postdoc and PhD positions at the IMDEA Software Institute, Madrid, Spain. The successful candidates will work under the supervision of Aleks Nanevski (http://software.imdea.org/~aleks/). The topic of the research, to be determined based on the common interests of the candidate and the supervisor, will be in the areas of software verification of concurrent programs, separation logic, and language-based security. The research will be funded by Aleks' ERC Consolidator grant "MATHADOR: Type and Proof Structures for Concurrent Software Verification", which aims to investigate the type-theoretic foundations for concurrency. PhD candidates should have an excellent MSc or BSc degree in computer science or a related subject, with an interest in the above areas, and a strong commitment to research. An MSc or a BSc thesis is a plus. PhD positions are for four years. Postdoc candidates should have, or expect shortly to obtain, a PhD in computer science. The ideal candidate will have expertise in program semantics and program logics, concurrent or distributed computing, type theory or interactive theorem proving, as they apply to the above areas. Postdoc positions are initially for one year, with possibilities for extension (depending on performance). The positions require good teamwork and communication skills, including excellent spoken and written English. Salaries at IMDEA Software Institute are internationally competitive. Interested applicants should contact Aleks directly (aleks dot nanevski at imdea dot org). Formal applications should be submitted online at https://careers.imdea.org/software/ and mention this announcement in the submitted materials. Review of applications will begin immediately.