API design governance is an important part of the API lifecycle and having tooling to hand to help with it is increasingly important in ensuring the quality and consistency of OpenAPI documents. In this session we look at one such tool, the Spectral OpenAPI linter from Stoplight. This is a live demo where we’ll work from the ground up in explaining how Spectral works. We will explain how to create custom rulesets and functions and give practical examples of how to modularize those rulesets making them fit for reuse across your organization.