tsconfig.json

{
    "compilerOptions": {
        "baseUrl": ".",
        "module": "es6",
        "moduleResolution": "node",
        "allowSyntheticDefaultImports": true,
        "target": "es2017",
        "experimentalDecorators": true,
        "noUnusedLocals": true,
        "strictNullChecks": true,
        "paths": {
            "util/*": ["./src/util/*"],
            "lwc": ["./node_modules/@lwc/engine"],
            "wire-service": ["./node_modules/@lwc/wire-service"],
            "store/*": ["./src/store/*"],
            "cmp/*": ["./src/ffmpeg/*"],
            "event/*": ["./src/event/*"],
            "notes/*": ["./src/notes/*"],
            "keyboard/*": ["./src/keyboard/*"],
            "markers/*": ["./src/markers/*"],
            "units/*": ["./src/units/*"],
            "audio/*": ["./src/audio/*"]
        }
    },
}