Package ocaml-variants

Failed to find a solution:

no platform:
2025-05-16 17:58.21 [INFO] Solving for ocaml-base-compiler,
                           ocaml-variants, constraints ocaml-base-compiler<=5.3.0,
                           ocaml-variants=5.2.0+msvc using opam_repository_commit cf409d95af00ff822422bd76b657ed213b661401

2025-05-16 17:58.23 [INFO] base: eliminated all possibilities in 0.48 s

2025-05-16 17:58.23 [INFO] = base =

2025-05-16 17:58.23 [INFO] Can't find all required versions.
Selected: base-bigarray.base base-domains.base base-nnp.base
          base-threads.base base-unix.base host-arch-x86_64.1 ocaml-config.3
          ocaml-variants&ocaml-base-compiler system-msvc host-arch-x86_64
          ocaml-base-compiler ocaml-base-compiler ocaml base-domains
- ocaml -> ocaml.5.2.0
    ocaml-variants 5.2.0+msvc requires = 5.2.0
- ocaml-base-compiler -> (problem)
    User requested <= 5.3.0
    Rejected candidates:
      ocaml-base-compiler.5.3.0: In same conflict class (ocaml-core-compiler) as ocaml-variants
      ocaml-base-compiler.5.3.0~rc1: In same conflict class (ocaml-core-compiler) as ocaml-variants
      ocaml-base-compiler.5.3.0~beta2: In same conflict class (ocaml-core-compiler) as ocaml-variants
      ocaml-base-compiler.5.3.0~beta1: In same conflict class (ocaml-core-compiler) as ocaml-variants
      ocaml-base-compiler.5.3.0~alpha1: In same conflict class (ocaml-core-compiler) as ocaml-variants
      ...
- ocaml-variants -> ocaml-variants.5.2.0+msvc
    User requested = 5.2.0+msvc
- system-msvc -> (problem)
    No usable implementations:
      system-msvc.1: Availability condition not satisfied
- winpthreads -> (problem)
    No usable implementations:
      winpthreads.20240209-1: Availability condition not satisfied