SuperTokens is a company that specializes in open-source user authentication solutions, enabling developers to easily integrate user sign-up and authentication functionalities into their applications. By providing a ready-to-use authentication system, SuperTokens allows developers to focus on their core product, significantly reducing the time required for implementation. The company is backed by Y Combinator and offers a flexible work environment, including remote work options. SuperTokens aims to address a critical pain point for developers by providing a robust infrastructure layer for web applications that require user login.