We are very proud to announce the availability of OPAM 1.2.0.

Upgrade from 1.1

Simply follow the usual instructions, using your preferred method (package from your distribution, binary, source, etc.) as documented on the homepage.

NOTE: There are small changes to the internal repository format (~/.opam). It will be transparently updated on first run, but in case you might want to go back and have anything precious there, you're advised to back it up.


Lot of work has been put into providing a cleaner interface, with helpful behaviour and messages in case of errors.

The documentation pages also have been largely rewritten for consistency and clarity.

New features

This is just the top of the list:

  • A extended and versatile opam pin command. See the Simplified packaging workflow
  • More expressive queries, see for example opam source
  • New metadata fields, including source repositories, bug-trackers, and finer control of package behaviour
  • An opam lint command to check the quality of packages

For more detail, see the announcement for the beta, the full changelog, and the bug-tracker.

Package format

The package format has been extended to the benefit of both packagers and users. The repository already accepts packages in the 1.2 format, and this won't affect 1.1 users as a rewrite is done on the server for compatibility with 1.1.

If you are hosting a repository, you may be interested in these administration scripts to quickly take advantage of the new features or retain compatibility.