smlpkg: A Package Manager for Standard ML

smlpkg makes it easier to share and reuse Standard ML libraries. It downloads and upgrades dependencies from repositories such as GitHub and GitLab, using semantic versioning to identify releases. It is independent of the compiler and fits naturally with MLB files used by MLton, MLKit, and SMLtoJs.

The everyday workflow is small: smlpkg add records a dependency in sml.pkg, and smlpkg sync downloads the required packages into the project’s lib directory. The resulting source files can then be included in the program’s build in the usual way. This keeps dependency management straightforward without prescribing how a project should be compiled.

The implementation is an almost complete port to Standard ML of the Futhark package manager, originally designed and implemented in Haskell by Troels Henriksen. His post, The Present Futhark Package Manager, explains the design and its emphasis on simple, transparent operations. For installation instructions and a collection of available Standard ML packages, see the smlpkg repository.