Voiden

Voiden is a Git-native API client that lets you design, test, and document APIs entirely in plain Markdown. Instead of proprietary collection formats, Voiden uses human-readable API blocks that live alongside your codebase — making collections fully version-controllable, reusable, and diffable through standard Git workflows.

The tool supports REST, GraphQL, and WebSocket APIs, and includes features for composing requests, managing environments, and generating OpenAPI documentation. Being offline-first with no mandatory cloud sync or account requirement, Voiden keeps your API workflows local and private by default.

Voiden is well-suited for developers and teams who prefer Markdown-based documentation, want tight integration between API testing and their documentation pipeline, and value the portability and transparency of plain-text formats over locked-in proprietary clients.