polymer-build/tsconfig.json

{
  "extends": "../../tsconfig-base.json",
  "compilerOptions": {
    "outDir": "./lib",
    "baseUrl": "./",
    "paths": {
      "parse5": [
        "node_modules/@types/parse5",
        "*"
      ],
      "ua-parser-js": [
        "node_modules/@types/ua-parser-js",
        "*"
      ]
    }
  },
  "include": [
    "custom_typings/**/*.d.ts",
    "src/**/*.ts"
  ]
}