[ICFP'26] Package Managers à la Carte

Package Managers à la Carte: A Formal Model of Dependency Resolution (Video, ICFP 2026) Ryan T. Gibb, Patrick Ferris, David Allsopp, Thomas Gazagnaire, Anil Madhavapeddy (University of Cambridge, UK; University of Cambridge, UK; Jane Street, UK; Tarides, France; University of Cambridge, UK) Abstract: Package managers are legion. Every programming language and operating system has its own solution, each with subtly different semantics for dependency resolution. This fragmentation prevents multilingual projects from expressing precise dependencies across language ecosystems; it leaves external system dependencies implicit and unversioned; and it obscures the full dependency graph that supply-chain analysis depends on. We present the Package Calculus, a formalism for dependency resolution that unifies the core semantics of package managers. Through a series of formal reductions, we show how this core is expressive enough to model the diversity of real-world dependency expression languages. The calculus provides the theoretical foundation for future cross-ecosystem tooling, as a lingua franca of dependency expression. Article: https://doi.org/10.1145/3828699 Supplementary archive: https://doi.org/10.5281/zenodo.21373302 (Badges: Artifacts Available, Artifacts Evaluated — Reusable) ORCID: https://orcid.org/0009-0009-5702-3143, https://orcid.org/0000-0002-0778-8828, https://orcid.org/0009-0006-2998-8210, https://orcid.org/0009-0001-6893-4630, https://orcid.org/0000-0001-8954-2428 Video Tags: package managers, dependency resolution, software ecosystems, doi:10.1145/3828699, doi:10.5281/zenodo.21373302, orcid:0009-0009-5702-3143, orcid:0000-0002-0778-8828, orcid:0009-0006-2998-8210, orcid:0009-0001-6893-4630, orcid:0000-0001-8954-2428, Artifacts Available, Artifacts Evaluated — Reusable Presentation at the ICFP 2026 conference, August 25-27, 2026, https://icfp26.sigplan.org/ Sponsored by ACM SIGPLAN.