Buf

The buf CLI is a tool for working with Protocol Buffers APIs, offering a range of features not found in the standard protoc compiler, including these core features:

• The ability to manage Protobuf assets, including plugins and templates, on the Buf Schema Registry (BSR).
• A linter that enforces good API design choices and structure.
• A breaking change detector that enforces compatibility at the source code or wire level.
• A generator that invokes your protoc plugins based on a configurable template.
• A protoc replacement that uses Buf's high-performance Protobuf compiler.
• A configurable file builder that produces images, our extension of Protobuf's native FileDescriptorSets.

Installation

Homebrew

You can install buf using Homebrew (macOS or Linux):

brew install bufbuild/buf/buf

This installs:

• The buf, protoc-gen-buf-breaking, and protoc-gen-buf-lint binaries
• Shell completion scripts for Bash, Fish, Powershell, and zsh

Other methods

For other installation methods, see our official documentation, which covers:

• Installing buf on Windows
• Using buf as a Docker image
• Installing as a binary, from a tarball, and from source through GitHub Releases
• Verifying releases using a minisign public key

Usage

Buf's help interface provides summaries for commands and flags:

buf --help

For more comprehensive usage information, consult Buf's documentation, especially these guides:

• buf breaking
• buf build
• buf generate
• buf lint
• buf registry (for using the BSR)

CLI breaking change policy

We will never make breaking changes within a given major version of the CLI. Once buf reaches v1.0, you can expect no breaking changes until v2.0. But as we have no plans to ever release a v2.0, we will likely never break the buf CLI.

This breaking change policy does not apply to commands behind the buf beta gate, and you should expect breaking changes to commands like buf beta registry. The policy does go into effect, however, when those commands or flags are elevated out of beta.

Our goals for Protobuf

Buf's goal is to replace the current paradigm of API development, centered around REST/JSON, with a schema-driven paradigm. Defining APIs using an IDL provides numerous benefits over REST/JSON, and Protobuf is by far the most stable and widely adopted IDL in the industry. We've chosen to build on this widely trusted foundation rather than creating a new IDL from scratch.

But despite its technical merits, actually using Protobuf has long been more challenging than it needs to be. The Buf CLI and the BSR are the cornerstones of our effort to change that for good and to make Protobuf reliable and easy to use for service owners and clients alike—in other words, to create a modern Protobuf ecosystem.

While we intend to incrementally improve on the buf CLI and the BSR, we're confident that the basic groundwork for such an ecosystem is already in place.

The Buf Schema Registry

The Buf Schema Registry (BSR) is a SaaS platform for managing your Protobuf APIs. It provides a centralized registry and a single source of truth for all of your Protobuf assets, including not just your .proto files but also plugins and code generation templates. Although the BSR provides an intuitive browser UI, buf enables you to perform most BSR-related tasks from the command line, such as pushing Protobuf sources to the registry and managing users and repositories. The BSR is currently in beta.

The BSR is purely opt-in. We've made the core features of the buf CLI available to all Protobuf users.

More advanced CLI features

While buf's core features should cover most use cases, we've included some more advanced features to cover edge cases:

• Automatic file discovery. Buf walks your file tree and builds your .proto files in accordance with your supplied build configuration, which means that you no longer need to manually specify --proto_paths. You can still, however, specify .proto files manually through CLI flags in cases where file discovery needs to be disabled.
• Fine-grained rule configuration for linting and breaking change. While we do have recommended defaults, you can always select the exact set of rules that your use case requires, with 40 lint rules and 53 breaking change rules available.
• Configurable error formats for CLI output. buf outputs information in file:line:column:message form by default for each lint error and breaking change it encounters, but you can also select JSON and, in the near future, JUnit output.
• Editor integration driven by buf's granular error output. We currently provide linting integrations for both Vim and Visual Studio Code but we plan to support other editors, such as Emacs and JetBrains IDEs like IntelliJ and GoLand, in the future.
• Universal Input targeting. But enables you to perform actions like linting and breaking change detection not just against local .proto files but also against a broad range of other Inputs, such as tarballs and ZIP files, remote Git repositories, and pre-built image files.
• Speed. Buf's internal Protobuf compiler compiles your Protobuf sources using all available cores without compromising deterministic output, which is considerably faster than protoc. This allows for near-instantaneous feedback, which is of special importance for features like [editor integration][id].

Next steps

Once you've installed buf, we recommend completing the Tour of Buf, which provides a broad but hands-on overview of the core functionality of both the CLI and the BSR. The tour takes about 10 minutes to complete.

After completing the tour, check out the remainder of the docs for your specific areas of interest and our roadmap to see what we have in store for the future.

Community

For help and discussion around Protobuf, best practices, and more, join us on Slack.

For updates on the Buf CLI, follow this repo on GitHub.

For feature requests, bugs, or technical questions, email us at dev@buf.build. For general inquiries or inclusion in our upcoming feature betas, email us at info@buf.build.