my-website/static/modversions/testingmod-updates.json

{
    "homepage": "https://gitlab.com/jotoho/mc-testingmod",
    "1.16.5": {
        "prealpha": "This 'version' has no changelog"
    },
    "promos": {
        "1.16.5-latest": "prealpha"
    }
}