Thomas Gazagnaire just announced the availability of the OPAM beta release. This has been a huge amount of work for him and Louis, so I’m excited to see this release! Aside from general stability, the main highlights for me are:

• A switch to the CC0 public-domain-like license for the repository, and LGPL2+linking exception for OPAM itself. The cutover to the new license was the first non-gratuitous use of GitHub’s fancy issue lists I’ve seen, too! As part of this, we’re also beginning a transition over to hosting it at opam.ocaml.org, to underline our committment to maintaining it as an OCaml community resource.

• Much-improved support for package pinning and updates. This is the feature that makes OPAM work well with MirageOS, since we often need to do development work on a low-level library (such as a device driver and recompile all the reverse dependencies.

• Support for post-installation messages (e.g. to display licensing information or configuration hints) and better support for the external library management issues I explained in an earlier post about OCamlot testing.

• Better library structuring to let tools like Opam2web work with the package metadata. For instance, my group’s OCaml Labs has a comprehensive list of the software packages that we work on generated directly from an OPAM remote.

• A growing set of administration tools (via the opam-admin binary) that run health checks and compute statistics over package repositories. For example, here’s the result of running opam-admin stats over the latest package repository to show various growth curves.