Bruno is a lightweight, open-source API client and IDE for exploring and testing APIs, built for developers and teams who want their request collections stored as plain text in a folder on their own filesystem rather than in a vendor's cloud.

What it is

Bruno is an API client written in JavaScript and released under the MIT licence, positioned by its maintainers as the open alternative to Postman. It lives in the API development and testing ecosystem, and it replaces the cloud-synced, account-bound API client with a local desktop application whose state is a directory of files. Collections are saved directly to the filesystem, and request information is stored in Bru, a plain text markup language. Because the collection is just files, any version control system can be used to track and share it; the README highlights Git specifically.

The concrete problem Bruno solves is data ownership and collaboration friction in API work. In the workflow it targets, request definitions live inside a proprietary cloud service, which makes them hard to diff, hard to review in a pull request, and dependent on a vendor account. Bruno moves those definitions onto disk in a text format that diffs cleanly, so a team can branch, review, and merge changes to its API collections the same way it treats application code. Bruno is offline-only, and the README states there are no plans to add cloud sync at any point.

Key capabilities

• Collections stored in a folder on the filesystem, with request data saved in the Bru plain text markup language.
• Collaboration through Git or any version control system of choice, since collections are ordinary files.
• Offline-only operation with no cloud sync, by explicit design decision stated in the README.
• A Bruno CLI for running collections outside the desktop application.
• Docker support, documented under "Run with Docker" in the README's table of contents.
• Protocol and specification coverage indicated by its topics: REST APIs, GraphQL via graphql-client, HTTP via http-client, and OpenAPI and OpenAPI 3.
• Automation support, listed among the project's topics alongside api-testing.

Who uses it and how

• Individual developers who want an API client that keeps request history and secrets on their own device instead of in a hosted account.
• Teams that already review application code in Git and want API collection changes to flow through the same pull request and review process.
• Engineers on Mac, Windows, and Linux, since the project ships across multiple platforms and is distributed through the package managers for each.
• CI and scripting workflows that invoke the Bruno CLI against a repository of Bru collections rather than a GUI.
• Organisations with data privacy or network-isolation requirements, given the offline-only design and the absence of any cloud-sync path.

Getting started

Bruno is distributed as a binary download from usebruno.com/downloads for Mac, Windows, and Linux, and is installable through package managers including Homebrew (brew install bruno), Chocolatey (choco install bruno), Scoop, winget (winget install Bruno.Bruno), Snap (snap install bruno), Flatpak (flatpak install com.usebruno.Bruno), AUR, and Apt. Running it in Docker is covered in the README, and the Bruno CLI provides the non-GUI entry point.

How it compares

The registry lists Postman as the paid product Bruno positions itself against as an open alternative. Bruno is MIT-licensed, where the README characterises the majority of its features as free and open source, with optional paid versions offered for additional features rather than as the only way to use the tool. On data ownership the contrast is explicit: Bruno stores collections in a local folder under the user's own version control and is offline-only with no cloud sync planned, which is the opposite of the account-hosted model that motivated the project in the first place.

When to use it — and when not to

A self-hoster must operate their own version control for any team collaboration, because there is no hosted sync option and the README rules one out permanently; whoever wants shared collections will need a Git remote or equivalent. Some functionality sits behind the paid versions, so teams that need those specific features should check the pricing page before standardising on the free build. The repository also carries a large open-issue count of 1,831 alongside a recent push, which suggests an active but heavily loaded tracker — worth weighing if the project is on a critical path.

# On Mac via Homebrew
brew install bruno

# On Windows via Chocolatey
choco install bruno

# On Windows via Scoop
scoop bucket add extras
scoop install bruno

# On Windows via winget
winget install Bruno.Bruno

# On Linux via Snap
snap install bruno

# On Linux via Flatpak
flatpak install com.usebruno.Bruno

# On Arch Linux via AUR
yay -S bruno

# On Linux via Apt
sudo mkdir -p /etc/apt/keyrings
sudo apt update && sudo apt install gpg curl
curl -fsSL "https://keyserver.ubuntu.com/pks/lookup?op=get&search=0x9FA6017ECABE0266" \
  | gpg --dearmor \
  | sudo tee /etc/apt/keyrings/bruno.gpg > /dev/null
sudo chmod 644 /etc/apt/keyrings/bruno.gpg
echo "deb [arch=amd64 signed-by=/etc/apt/keyrings/bruno.gpg] http://debian.usebruno.com/ bruno stable" \
  | sudo tee /etc/apt/sources.list.d/bruno.list
sudo apt update && sudo apt install bruno

npm install -g @usebruno/cli

# Run every request in the collection
bru run

# Run a single request
bru run request.bru

# Run a folder against a specific environment
bru run folder --env Local

# Pull from Docker Hub
docker pull usebruno/cli:latest

# Or pull from the GitHub Container Registry
docker pull ghcr.io/usebruno/cli:latest

# Run a collection by mounting the current directory
docker run -v $(pwd):/bruno usebruno/cli run