Bruno is an open-source, Git-native API client for testing and exploring REST, GraphQL, gRPC, and WebSocket APIs, designed as a privacy-focused alternative to cloud-dependent tools like Postman and Insomnia. It solves the fundamental problem of API collection portability and collaboration by storing all request definitions as plain-text .bru files directly on your filesystem, enabling version control with Git and eliminating the need for cloud accounts, subscriptions, or proprietary sync services. Bruno has rapidly grown to over 40,000 GitHub stars, becoming one of the fastest-growing API development tools in the open-source ecosystem.
Bruno's core differentiator is its local-first, offline-only architecture that never syncs data to the cloud and requires no login or account creation. The .bru markup language is human-readable and diff-friendly, making API collections first-class citizens in your Git repository alongside application code. Bruno supports environment and variable management, pre-request scripts, test assertions, and a CLI tool (@usebruno/cli) that outputs JUnit XML for seamless CI/CD integration with GitHub Actions, GitLab CI, Jenkins, and other pipeline tools. It also supports importing Postman Collection v2.1 JSON files for easy migration.
Bruno is built for developers and QA engineers who value data ownership, offline access, and Git-based collaboration over cloud-dependent workflows. It is particularly appealing to security-conscious teams and organizations that cannot or prefer not to store API collections on third-party servers. Bruno integrates naturally into existing development workflows where code, configuration, and API definitions all live in the same repository, enabling pull request reviews of API changes alongside code changes and ensuring complete reproducibility across development environments.