Bruno API Client Review: The Git-Friendly Open Source Alternative to Postman

Bruno API Client Review: The Git-Friendly Open Source Alternative to Postman

API testing tools have quietly become a load-bearing part of modern development workflows. Postman alone reports more than 35 million registered users, and Insomnia, Paw, and Thunder Client have carved out their own niches. Yet a persistent complaint runs through developer forums and GitHub issues: these tools store your API collections in proprietary formats, often in the cloud, which makes version control awkward and collaboration dependent on someone else’s servers.

Bruno is a direct response to that complaint. Launched in 2022 by a small team, it has grown into one of the more interesting open source challengers in the API client space, with more than 30,000 GitHub stars as of 2025. This review looks at what Bruno does well, where it falls short, and who should consider switching.

What Bruno Actually Is

Bruno is a desktop API client for exploring and testing HTTP and REST APIs. It runs natively on macOS, Windows, and Linux, and it’s built with Electron and React. The headline feature isn’t a new protocol or a faster request engine. It’s the storage model.

Most API clients save collections in a database or a cloud account. Bruno saves them as plain-text files with a .bru extension, organized in folders on your local filesystem. Each request is a human-readable file that looks roughly like this:

meta {
  name: Get Users
  type: http
  seq: 1
}

get {
  url: https://api.example.com/users
  body: none
  auth: bearer
}

auth:bearer {
  token: {{apiToken}}
}

That’s it. No JSON blobs, no database, no proprietary binary format. You point Bruno at a folder, and that folder becomes your collection. Commit it to Git, review changes in a pull request, branch it, merge it — the same workflow you already use for code.

Why the Git-Friendly Model Matters

The pitch sounds almost too simple, but the practical consequences are significant.

Diffable changes. When a teammate updates an endpoint URL or adds a header, the change shows up as a line-level diff in Git. Compare that to Postman’s collection format, which is a large JSON file where a single logical change can produce dozens of lines of noise, or to cloud-synced collections where you may not see a diff at all.

No account required. Bruno doesn’t ask you to sign in. There’s no cloud sync by default, no telemetry phoning home with your request data, and no risk that a vendor changes its pricing tier and locks your collections behind a paywall. For teams in regulated industries — finance, healthcare, government — that matters.

Offline by default. Because collections live on disk, Bruno works on a plane, in an air-gapped environment, or on a flaky hotel Wi-Fi connection. You lose nothing.

Secrets stay separate. Bruno supports environment files and .env-style variable management. You can commit the collection structure while keeping tokens and credentials out of version control, which is the pattern most teams already follow for application code.

Feature Set: What You Get

Bruno covers the essentials and a growing list of nice-to-haves.

• Request types: GET, POST, PUT, PATCH, DELETE, HEAD, OPTIONS, and others
• Auth: Bearer tokens, basic auth, API keys, OAuth 2.0, AWS Signature v4, Digest, NTLM
• Body types: JSON, form data, URL-encoded, XML, multipart, GraphQL, plain text
• Scripting: Pre-request and post-response JavaScript, with a req and res API similar in spirit to Postman’s
• Assertions: Basic test scripting for status codes, response bodies, and headers
• Environments: Multiple named environments with variable substitution via {{variable}}
• Collections runner: Run a folder of requests sequentially, with a CLI (bru) for CI pipelines
• Import: Postman collections, OpenAPI specs, Insomnia, and OpenAPI export
• Code generation: Generate snippets in curl, JavaScript, Python, and other languages

The CLI is worth calling out. bru run lets you execute a collection in a CI job and fail the build on assertion errors, which turns Bruno from a manual testing tool into something closer to an automated test runner.

Where Bruno Falls Short

No tool is perfect, and Bruno has real gaps.

Collaboration without cloud sync. The Git model is great if your team already lives in Git. If your QA team doesn’t use version control, or if you’re sharing collections with external partners, the workflow is clunkier than Postman’s share-a-link approach. Bruno does offer a paid team plan with cloud sync, but that reintroduces the dependency the tool was built to avoid.

Smaller ecosystem. Postman has thousands of public API collections, a marketplace, mock servers, monitoring, and API documentation hosting. Bruno has none of that at comparable scale. If you rely on Postman’s mock servers or its API network, you’ll miss them.

Performance on large collections. Bruno is Electron-based, and very large collections (hundreds of requests) can feel sluggish compared to native apps. It’s improved across releases but isn’t the fastest client on the market.

Documentation and onboarding. The docs are decent but thinner than Postman’s. New users coming from a GUI-first tool may need an afternoon to get comfortable with the folder-based model.

Team features are still maturing. Role-based access, audit logs, and enterprise-grade governance are limited compared to commercial alternatives. For a five-person startup this is fine; for a 500-person enterprise with compliance requirements, it’s a consideration.

Bruno vs. Postman vs. Insomnia

Feature	Bruno	Postman	Insomnia
Storage format	Plain text files	Cloud/JSON	JSON/cloud
Git-friendly	Native	Awkward	Partial
Free tier	Full app, open source	Limited	Limited
Cloud sync	Paid add-on	Core feature	Core feature
Offline use	Yes	Limited	Limited
Open source	Yes (MIT)	No	Partially
Mock servers	No	Yes	Limited

Postman remains the more capable platform if you need mocking, monitoring, documentation hosting, and a large public network. Insomnia sits somewhere in between. Bruno’s advantage is narrow but sharp: it treats your API collection like code.

Who Should Use Bruno

Bruno is a strong fit if you:

• Work on a team that already uses Git for everything and wants API collections in the same review flow
• Need an offline-capable client with no account requirement
• Care about open source licensing and data ownership
• Want a CLI that plugs into CI without a paid plan

It’s a weaker fit if you:

• Depend on Postman’s mock servers, monitoring, or public API network
• Collaborate with non-technical stakeholders who won’t use Git
• Need enterprise governance features like SSO, audit logs, and granular permissions out of the box

The Bottom Line

Bruno isn’t trying to out-feature Postman. It’s trying to fix one specific problem — the mismatch between how developers version code and how most API clients store collections — and it does that well. The plain-text format is genuinely pleasant to work with, the app is fast enough for everyday use, and the open source license removes a category of vendor risk that more teams are starting to take seriously.

If your team lives in Git and you’ve ever groaned at a 400-line diff on a Postman collection, Bruno is worth a download. It won’t replace Postman for everyone, but for a growing slice of development teams, it’s the more sensible default.