tsconfig.json

{
  "$schema": "http://json.schemastore.org/tsconfig",

  "compilerOptions": {
    "outDir": "lib-esm",
    "rootDirs": ["src", "temp/image-typings"],

    "forceConsistentCasingInFileNames": true,
    "esModuleInterop": true,
    "allowSyntheticDefaultImports": true,
    "jsx": "react",
    "declaration": true,
    "sourceMap": true,
    "declarationMap": true,
    "inlineSources": true,
    "experimentalDecorators": true,
    "strictNullChecks": true,
    "noUnusedLocals": true,
    "types": ["heft-jest", "webpack-env"],
    "incremental": true,
    "isolatedModules": true,

    "module": "esnext",
    "moduleResolution": "node",
    "target": "es5",
    "lib": ["es5", "scripthost", "es2015.collection", "es2015.promise", "es2015.iterable", "dom"]
  },
  "include": ["src/**/*.ts", "src/**/*.tsx"]
}