The documentation for Dune says that Configurator is now part of Dune: https://dune.readthedocs.io/en/stable/dune-libs.html?highlight=configurator#configurator-1
However trying out the example fails:
$ cat >dune <<EOF
(executable
(name discover)
(libraries dune-configurator))
EOF
$ echo 'module C = Configurator.V1' >discover.ml
$ dune build
3 | (libraries dune-configurator))
^^^^^^^^^^^^^^^^^
Error: Library "dune-configurator" not found.
Here is what the dune-configurator would contain if opam was used to install it:
```
opam info --list-files dune-configurator
/home/edwin/.opam/4.11.2/doc/dune-configurator
/home/edwin/.opam/4.11.2/doc/dune-configurator/CHANGES.md
/home/edwin/.opam/4.11.2/doc/dune-configurator/LICENSE.md
/home/edwin/.opam/4.11.2/doc/dune-configurator/README.md
/home/edwin/.opam/4.11.2/lib/dune-configurator
/home/edwin/.opam/4.11.2/lib/dune-configurator/.private/configurator__Dune_lang.cmi
/home/edwin/.opam/4.11.2/lib/dune-configurator/.private/configurator__Dune_lang.cmt
/home/edwin/.opam/4.11.2/lib/dune-configurator/.private/configurator__Dune_lang.cmti
/home/edwin/.opam/4.11.2/lib/dune-configurator/.private/configurator__Import.cmi
/home/edwin/.opam/4.11.2/lib/dune-configurator/.private/configurator__Import.cmt
/home/edwin/.opam/4.11.2/lib/dune-configurator/.private/configurator__Ocaml_config.cmi
/home/edwin/.opam/4.11.2/lib/dune-configurator/.private/configurator__Ocaml_config.cmt
/home/edwin/.opam/4.11.2/lib/dune-configurator/.private/configurator__Ocaml_config.cmti
/home/edwin/.opam/4.11.2/lib/dune-configurator/META
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator.a
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator.cma
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator.cmi
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator.cmt
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator.cmx
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator.cmxa
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator.cmxs
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator.ml
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__.cmi
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__.cmt
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__.cmx
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__.ml
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__Dune_lang.cmx
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__Extract_obj.cmi
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__Extract_obj.cmt
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__Extract_obj.cmti
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__Extract_obj.cmx
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__Import.cmx
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__Ocaml_config.cmx
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__V1.cmi
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__V1.cmt
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__V1.cmti
/home/edwin/.opam/4.11.2/lib/dune-configurator/configurator__V1.cmx
/home/edwin/.opam/4.11.2/lib/dune-configurator/dune-package
/home/edwin/.opam/4.11.2/lib/dune-configurator/dune_lang.ml
/home/edwin/.opam/4.11.2/lib/dune-configurator/dune_lang.mli
/home/edwin/.opam/4.11.2/lib/dune-configurator/extract_obj.ml
/home/edwin/.opam/4.11.2/lib/dune-configurator/extract_obj.mli
/home/edwin/.opam/4.11.2/lib/dune-configurator/import.ml
/home/edwin/.opam/4.11.2/lib/dune-configurator/ocaml_config.ml
/home/edwin/.opam/4.11.2/lib/dune-configurator/ocaml_config.mli
/home/edwin/.opam/4.11.2/lib/dune-configurator/opam
/home/edwin/.opam/4.11.2/lib/dune-configurator/v1.ml
/home/edwin/.opam/4.11.2/lib/dune-configurator/v1.mli
```
Fedora includes it: https://src.fedoraproject.org/rpms/ocaml-dune/c/715e50af8739785e9d4db2567780075900711ff9
However Ubuntu 20.04.4 LTS does not (with ocaml-dune 2.1.3-2):
dpkg -L ocaml-dune|grep configurator
Please install the dune-configurator OCaml package when building Dune: it is *part* of Dune according to its documentation.
(Previously it used to be an independent library, but now it is part of the dune source code).
ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: ocaml-dune 2.1.3-2
ProcVersionSignature: Ubuntu 5.13.0-37.42~20.04.1-generic 5.13.19
Uname: Linux 5.13.0-37-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.21
Architecture: amd64
CasperMD5CheckResult: skip
Date: Thu Mar 24 17:07:44 2022
InstallationDate: Installed on 2021-03-02 (387 days ago)
InstallationMedia: Ubuntu 20.04.2.0 LTS "Focal Fossa" - Release amd64 (20210209.1)
SourcePackage: ocaml-dune
UpgradeStatus: No upgrade log present (probably fresh install)
