OCaml 4.08.0 beta1 release

(cross posted from @damiendoligez’s post to the caml-list)

The release of OCaml 4.08.0 is approaching. We have created a beta version to help you adapt your software to the new features ahead of the release.

The source code is available at these addresses:


The compiler can also be installed as an OPAM switch with one of the following commands.

opam switch create ocaml-variants.4.08.0+beta1 --repositories=default,beta=git+https://github.com/ocaml/ocaml-beta-repository.git


opam switch create ocaml-variants.4.08.0+beta1+VARIANT --repositories=default,beta=git+https://github.com/ocaml/ocaml-beta-repository.git

where you replace VARIANT with one of these:

  • afl (for fuzzing support)
  • default_unsafe_string
  • flambda
  • fp
  • fp+flambda

We want to know about all bugs. Please report them here:

(and an addendum to the original message from me)

In particular, this a good time to check your libraries for compatibility with OCaml 4.08 and cut releases for submission to opam. The 4.08 changelog will provide guidance into new features and bugfixes relevant to your own projects.