Package ocaml-variants

Failed to find a solution:

no platform:
2025-05-16 17:58.19 [INFO] Solving for ocaml-base-compiler,
                           ocaml-variants, constraints ocaml-base-compiler<=5.3.0,
                           ocaml-variants=5.4.0+trunk using opam_repository_commit cf409d95af00ff822422bd76b657ed213b661401

2025-05-16 17:58.21 [INFO] base: eliminated all possibilities in 0.52 s

2025-05-16 17:58.21 [INFO] = base =

2025-05-16 17:58.21 [INFO] Can't find all required versions.
Selected: base-bigarray.base base-domains.base base-effects.base
          base-nnp.base base-threads.base base-unix.base host-arch-x86_64.1
          ocaml-config.3 ocaml-variants&ocaml-base-compiler system-mingw
          system-mingw|system-msvc&winpthreads host-arch-x86_64
          ocaml-base-compiler ocaml-base-compiler base-domains ocaml ocaml
- ocaml -> ocaml.5.4.0
    ocaml-compiler 5.4 requires = 5.4.0
- 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-compiler -> ocaml-compiler.5.4
    ocaml-variants 5.4.0+trunk requires = 5.4
- ocaml-variants -> ocaml-variants.5.4.0+trunk
    User requested = 5.4.0+trunk
- system-mingw -> (problem)
    No usable implementations:
      system-mingw.1: Availability condition not satisfied