Modern JavaScript libraries: the isomorphic way

Algolia has modernized its JavaScript client, which is now an isomorphic API that can run both client-side and server-side. The new client includes features such as unit testing, HTTP request mocking, and support for promises and callbacks. It also follows the error-first and callback-last conventions to make it compatible with libraries like caolan/async. The client is UMD compatible, allowing it to be used in various module loaders, including AMD, CommonJS, and ES6 modules.