A lot of packages have types built into them.

Others have types available in "@types/<package>".

For everything else, I create a "types.d.ts" file that just has a bunch of stuff like:

declare module 'twilio';

declare module 'bitly';

declare module 'cloudinary';

declare module 'tmp-promise';

declare module 'dialogflow';

declare module 'fuel-rest';

And then those modules get set to the "any" type.