Core is an industrial-strength alternative to the OCaml standard library. It was developed by Jane Street, which is the largest industrial user of OCaml.
Core_kernel is the system-independent part of Core. It is aimed for cases when the full Core is not available, such as in Javascript. It provides an overlay on the usual namespace, so the best way to use Core is to start your file with:
open Core_kernel.StdPlease report bugs and feature requests on GitHub. For everything else you can contact us at ocaml-core@googlegroups.com.
You can find all of Jane Street's open-source libraries on GitHub.