Package cstruct

Failed to find a solution:

no platform:
2024-01-29 14:45.50 [INFO] Solving for ocaml-base-compiler, ocaml,
                           cstruct using opam_repository_commit 251c5edf2ecdd2541c324dacb931c3606ee71eeb

2024-01-29 14:45.55 [INFO] base: eliminated all possibilities in 2.39 s

2024-01-29 14:45.55 [INFO] = base =

2024-01-29 14:45.55 [INFO] Can't find all required versions.
Selected: base-bytes.base base-num.base base-threads.base base-unix.base
          conf-time.1 conf-which.1 cppo.1.6.9 dune.3.13.0 num.0
          ocaml-config.3 ocaml-secondary-compiler.4.08.1-1 ocamlbuild.0.14.3
          ocamlfind.1.9.6 ocamlfind-secondary.1.9.6 ocplib-endian.1.2
          sexplib.v0.9.2 cstruct&ocaml&ocaml-base-compiler
          ocaml-base-compiler ocaml-base-compiler ocaml&ocamlfind-secondary
- cstruct -> cstruct.2.1.0
    User requested = 2.1.0
- jbuilder -> jbuilder.1.0+beta20.2
    dune 3.13.0 requires not(= transition)
- ocaml -> ocaml.4.03.1
    User requested <= 5.1.0
    base-num base requires < 4.06.0
    cstruct 2.1.0 requires >= 4.02.3 & < 4.04.0
- ocaml-base-compiler -> (problem)
    User requested >= 4.04.1
    Rejected candidates:
      ocaml-base-compiler.5.1.1: Requires ocaml = 5.1.1
      ocaml-base-compiler.5.1.1~rc1: Requires ocaml = 5.1.1
      ocaml-base-compiler.5.1.0: Requires ocaml = 5.1.0
      ocaml-base-compiler.5.1.0~rc3: Requires ocaml = 5.1.0
      ocaml-base-compiler.5.1.0~rc2: Requires ocaml = 5.1.0
      ...