The sources of the following couldn't be obtained, aborting: - erlang.0.0.14

[hvnsweeting]

Describe the bug
I'm trying to build Caramel on OpenBSD 6.8, as no binary provided, so I compile from source.

I ran gmake setup and got the error:

$ gmake setup 
opam install ./erlang/erlang.opam
The following actions will be performed:
  ∗ install dune                    2.8.4    [required by erlang]
  ∗ install cmdliner                1.0.4    [required by erlang]
  ∗ install conf-m4                 1        [required by ocamlfind]
  ∗ install stdlib-shims            0.3.0    [required by ppxlib]
  ∗ install sexplib0                v0.14.0  [required by ppx_sexp_conv, sexplib]
  ∗ install result                  1.5      [required by dune-configurator]
  ∗ install ppx_derivers            1.2.1    [required by ppxlib]
  ∗ install ocaml-migrate-parsetree 2.1.0    [required by ppxlib]
  ∗ install ocaml-compiler-libs     v0.12.3  [required by ppxlib]
  ∗ install menhirSdk               20210310 [required by menhir]
  ∗ install menhirLib               20210310 [required by menhir]
  ∗ install ocamlfind               1.8.1    [required by num]
  ∗ install csexp                   1.4.0    [required by dune-configurator]
  ∗ install ppxlib                  0.22.0   [required by ppx_sexp_conv]
  ∗ install menhir                  20210310 [required by erlang]
  ∗ install num                     1.4      [required by sexplib]
  ∗ install dune-configurator       2.8.4    [required by base]
  ∗ install base                    v0.14.1  [required by ppx_sexp_conv]
  ∗ install ppx_sexp_conv           v0.14.3  [required by erlang]
  ∗ install parsexp                 v0.14.0  [required by sexplib]
  ∗ install sexplib                 v0.14.0  [required by erlang]
  ∗ install erlang                  0.0.14
***===== ∗ 22 =====***
Do you want to continue? [Y/n] y

<><> Gathering sources ><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
[base.v0.14.1] found in cache
[cmdliner.1.0.4] found in cache
Processing  3/22:
[csexp.1.4.0] found in cache
[dune.2.8.4] found in cache
[dune-configurator.2.8.4] found in cache
[menhir.20210310] found in cache
[menhirLib.20210310] found in cache
[menhirSdk.20210310] found in cache
[num.1.4] found in cache
[ocaml-compiler-libs.v0.12.3] found in cache
[ocaml-migrate-parsetree.2.1.0] found in cache
[ocamlfind.1.8.1] found in cache
[parsexp.v0.14.0] found in cache
[ppx_derivers.1.2.1] found in cache
[ppx_sexp_conv.v0.14.3] found in cache
[ppxlib.0.22.0] found in cache
[result.1.5] found in cache
[sexplib.v0.14.0] found in cache
[sexplib0.v0.14.0] found in cache
[stdlib-shims.0.3.0] found in cache
[ERROR] The sources of the following couldn't be obtained, aborting:
          - erlang.0.0.14

gmake: *** [Makefile:28: setup] Error 40

Expected behavior
Setup successful.

Environment (please complete the following information):

• OS: OpenBSD 6.8
• Caramel version: 0.1.0 - master at c34a952
• Erlang version: Erlang/OTP 21 [erts-10.2] [source] [64-bit] [smp:8:4] [ds:8:4:10] [async-threads:1]
• Ocaml: ocaml --version
  The OCaml toplevel, version 4.12.0