ruffle/web/packages/core/tsconfig.json

{
  "compilerOptions": {
    "module": "esnext",
    "outDir": "pkg",
    "target": "es6",
    "strict": true,
    "esModuleInterop": true
  },
  "include": ["./src/**/*"],
  "exclude": ["./dist", "./pkg", "./docs"]
}