schemas/platform.schema.json

{
  "$schema": "https://json-schema.org/draft/2019-09/schema",
  "type": "object",
  "required": ["target"],
  "additionalProperties": false,
  "properties": {
    "target": {
      "type": "string",
      "pattern": "^(?![0-9])([a-z0-9]+-?)+(?<!-)$"
    },
    "variants": {
      "additionalProperties": false,
      "patternProperties": {
        "^(?![0-9])([A-Z0-9][a-z0-9]*-?)+(?<!-)$": {
          "type": "object"
        }
      }
    }
  }
}