Package unison

Failed to find a solution:

no platform:
2024-01-29 14:44.46 [INFO] Solving for ocaml-base-compiler, ocaml,
                           unison using opam_repository_commit 251c5edf2ecdd2541c324dacb931c3606ee71eeb

2024-01-29 14:44.51 [INFO] base: eliminated all possibilities in 2.41 s

2024-01-29 14:44.51 [INFO] = base =

2024-01-29 14:44.51 [INFO] Can't find all required versions.
Selected: conf-gtk2.1 conf-pkg-config.3 lablgtk.2.18.5 ocaml-config.3
          ocamlfind.1.9.6 unison&ocaml&ocaml-base-compiler
          ocaml-base-compiler ocaml-base-compiler
- ocaml -> ocaml.4.02.4
    User requested <= 5.1.0
    lablgtk 2.18.5 requires >= 3.11.0 & < 4.06
    unison 2.48.3 requires < 4.03.0
- 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
      ...
- unison -> unison.2.48.3
    User requested = 2.48.3