Bla_v1.rakumod

sub bla is export { say "v1" }

Bla_v2.rakumod

sub bla is export { say "v2" }

main.raku

use Bla;

bla

META6.json

{
  "name": "TestVersions",
  "perl": "6.d",
  "provides": {
    "TestVersions": "lib/TestVersions.rakumod",
    "Bla": "Bla_v1.rakumod",
    "Bla:ver<1>": "Bla_v1.rakumod",
    "Bla:ver<2>": "Bla_v2.rakumod",
  }
}