Stoplight

Stoplight approaches API management from the very beginning of the lifecycle: design and documentation. Many engineering teams write the code for their API first, and then attempt to write documentation for it later. Stoplight enforces a "Design-First" methodology using the OpenAPI Specification (formerly Swagger). Engineers use Stoplight's visual editor to design the endpoints, define what the JSON responses will look like, and establish the error codes before a single line of backend code is actually written. This creates an immediate "mock server." Frontend developers can start building the user interface by pinging the mock server, while the backend team simultaneously builds the actual database logic, drastically reducing development bottlenecks. Once the design is complete, Stoplight automatically generates beautiful, interactive documentation that stays perfectly in sync with the design files. Acquired by SmartBear (the company behind Swagger), it does not act as an API gateway for routing live production traffic. Instead, it is a collaborative workspace focused entirely on standardizing API design across massive engineering departments to prevent messy, inconsistent endpoints.