Yaak

Yaak is a local-first desktop API client for REST, GraphQL, gRPC, WebSocket, and Server-Sent Events. Every request, folder, and environment is stored as its own YAML file on your machine, so collections live next to your code and can be committed, diffed, and shared through the Git workflow your team already uses — with no account, no mandatory cloud sync, and no proprietary workspace format.

Built with Rust and Tauri, Yaak is tuned for speed: it stays responsive with thousands of requests, lets you chain requests and reuse values without writing scripts, and exposes every redirect, header, and timing detail of a request. OAuth2, JWT, and basic auth are supported out of the box, secrets can be encrypted with keys held in the OS keychain, and plugins extend auth handlers, importers, and template functions. Importers cover Postman, Insomnia, Bruno, OpenAPI, and raw cURL, while a companion CLI and MCP server let agents work against the same collections.

Yaak is MIT-licensed and free for individual use, with optional per-seat team plans that add SSO and SCIM provisioning. It suits developers and security-conscious teams who want a fast, offline-capable alternative to Postman or Insomnia that keeps API collections under version control.