As the API specification ecosystem matures, we're seeing more tools built to automate style checks. Zally is a minimalist OpenAPI linter that helps to ensure an API conforms to the team's API style guide. Out of the box, it will validate against a rule set developed for Zalando's API style guide, but it also supports a Kotlin extension mechanism to develop custom rules. Zally includes a web UI that provides an intuitive interface for understanding style violations and includes a CLI that makes it easy to plug into your CD pipeline.