Package capnp

Failed to find a solution:

no platform:
2025-05-16 17:24.32 [INFO] Solving for ocaml-base-compiler,
                           capnp, constraints ocaml-base-compiler<=5.3.0,
                           capnp=3.0.0 using opam_repository_commit cf409d95af00ff822422bd76b657ed213b661401

2025-05-16 17:24.33 [INFO] base: eliminated all possibilities in 0.60 s

2025-05-16 17:24.33 [INFO] = base =

2025-05-16 17:24.33 [INFO] Can't find all required versions.
Selected: base-bigarray.base base-bytes.base base-threads.base base-unix.base
          base_bigstring.v0.17.0 base_quickcheck.v0.17.0 bin_prot.v0.17.0
          capitalization.v0.17.0 conf-capnproto.2 core.v0.17.1
          core_kernel.v0.17.0 cppo.1.8.0 csexp.1.5.2 dune-configurator.3.18.2
          extunix.0.4.4 fieldslib.v0.17.0 gel.v0.17.0 int_repr.v0.17.0
          jane-street-headers.v0.17.0 jbuilder.transition jst-config.v0.17.0
          num.1.5-1 ocaml.5.5.0 ocaml-config.3 ocaml-options-vanilla.1
          ocamlfind.1.9.8 ocplib-endian.1.2 parsexp.v0.17.0
          ppx_assert.v0.17.0 ppx_base.v0.17.0 ppx_bench.v0.17.0
          ppx_bin_prot.v0.17.0 ppx_cold.v0.17.0 ppx_compare.v0.17.0
          ppx_custom_printf.v0.17.0 ppx_diff.v0.17.0
          ppx_disable_unused_warnings.v0.17.0 ppx_enumerate.v0.17.0
          ppx_expect.v0.17.2 ppx_fields_conv.v0.17.0
          ppx_fixed_literal.v0.17.0 ppx_globalize.v0.17.0 ppx_hash.v0.17.0
          ppx_here.v0.17.0 ppx_ignore_instrumentation.v0.17.0
          ppx_inline_test.v0.17.0 ppx_jane.v0.17.0 ppx_let.v0.17.0
          ppx_log.v0.17.0 ppx_module_timer.v0.17.0 ppx_optcomp.v0.17.0
          ppx_optional.v0.17.0 ppx_pipebang.v0.17.0 ppx_sexp_conv.v0.17.0
          ppx_sexp_message.v0.17.0 ppx_sexp_value.v0.17.0 ppx_stable.v0.17.0
          ppx_stable_witness.v0.17.0 ppx_string.v0.17.0
          ppx_string_conv.v0.17.0 ppx_tydi.v0.17.0 ppx_typerep_conv.v0.17.0
          ppx_variants_conv.v0.17.0 ppxlib_jane.v0.17.2 res.5.0.2
          sexplib.v0.17.0 sexplib0.v0.17.0 splittable_random.v0.17.0
          stdint.0.7.2 stdio.v0.17.0 time_now.v0.17.0 typerep.v0.17.1
          uint.2.0.1 uopt.v0.17.0 variantslib.v0.17.0
          capnp&ocaml-base-compiler ocaml-variants ocaml-base-compiler
          ocaml-base-compiler
- base -> (problem)
    capnp 3.0.0 requires not(>= v0.10.0)
    Rejected candidates:
      base.v0.17.2: Incompatible with restriction: not(>= v0.10.0)
      base.v0.17.1: Incompatible with restriction: not(>= v0.10.0)
      base.v0.17.0: Incompatible with restriction: not(>= v0.10.0)
      base.v0.16.4: Requires sexplib0 >= v0.16 & < v0.17
      base.v0.16.3: Requires sexplib0 >= v0.16 & < v0.17
      ...
- capnp -> capnp.3.0.0
    User requested = 3.0.0
- dune -> (problem)
    base_bigstring v0.17.0 requires >= 3.11.0
    Rejected candidates:
      dune.3.18.2: Requires jbuilder not(= transition)
      dune.3.18.1: Requires jbuilder not(= transition)
      dune.3.18.0: Requires jbuilder not(= transition)
      dune.3.17.2: Requires jbuilder not(= transition)
      dune.3.17.1: Requires jbuilder not(= transition)
      ...
- ocaml-base-compiler -> ocaml-base-compiler.5.3.0
    User requested <= 5.3.0
- ocaml-compiler -> (problem)
    ocaml-base-compiler 5.3.0 requires = 5.3.0
    Rejected candidates:
      ocaml-compiler.5.5: Incompatible with restriction: = 5.3.0
      ocaml-compiler.5.4: Incompatible with restriction: = 5.3.0
      ocaml-compiler.5.3.0: Requires ocaml = 5.3.0
      ocaml-compiler.5.3.0~rc1: Incompatible with restriction: = 5.3.0
      ocaml-compiler.5.3.0~beta2: Incompatible with restriction: = 5.3.0
      ...
- ocaml-variants -> (problem)
    Rejected candidates:
      ocaml-variants.5.5.0+trunk: In same conflict class (ocaml-core-compiler) as ocaml-base-compiler
      ocaml-variants.5.4.0+trunk: In same conflict class (ocaml-core-compiler) as ocaml-base-compiler
      ocaml-variants.5.3.1+trunk: In same conflict class (ocaml-core-compiler) as ocaml-base-compiler
      ocaml-variants.5.3.0+options: In same conflict class (ocaml-core-compiler) as ocaml-base-compiler
      ocaml-variants.5.3.0+BER: In same conflict class (ocaml-core-compiler) as ocaml-base-compiler
      ...
- ppxlib -> (problem)
    base_quickcheck v0.17.0 requires >= 0.28.0 & < 0.36.0
    extunix 0.4.4 requires >= 0.36.0
    Rejected candidates:
      ppxlib.0.36.0: Incompatible with restriction: >= 0.28.0 & < 0.36.0
      ppxlib.0.35.0: Incompatible with restriction: >= 0.36.0
      ppxlib.0.34.0: Incompatible with restriction: >= 0.36.0
      ppxlib.0.33.0: Incompatible with restriction: >= 0.36.0
      ppxlib.0.32.1: Incompatible with restriction: >= 0.36.0
      ...