ens-usernames/config/contracts.json

{
  "default": {
    "deployment": {
      "host": "localhost",
      "port": 8545,
      "type": "rpc"
    },
    "dappConnection": [
      "$WEB3",
      "http://localhost:8545"
    ],
    "gas": "auto",
    "contracts": {
      "TestToken": {
        "args": [ ]
      },
      "ENSRegistry": {
        "args": []
      },
      "PublicResolver": {
        "args": [
          "$ENSRegistry"
        ]
      },
      "ENSSubdomainRegistry": {
        "args": [
          "$TestToken", 
          "$ENSRegistry",
          "$PublicResolver",
          "0x0"
        ]
      }
    }
  }
}