The annual ACM SIGPLAN-SIGACT Symposium on Principles of Programming Languages (POPL) is an academic conference in the field of computer science, with focus on fundamental principles in the design, definition, analysis, and implementation of programming languages, programming systems, and programming interfaces. The venue is jointly sponsored by two Special Interest Groups of the Association for Computing Machinery: SIGPLAN and SIGACT. POPL ranks as A* (top 4%) in the CORE conference ranking.