Bloom

Bloom is a native macOS app for working with coding agents in Git worktrees. Each workspace has its own branch and directory. The app puts conversations, terminals, a browser, changed files and pull requests in one window.

Install

Bloom requires macOS 26 or later. Install the signed and notarised app with Homebrew:

brew install --cask spatie/bloom/spatie-bloom

Or download the disk image and drag Bloom to Applications. Sparkle checks for updates from inside the app.

Install at least one supported agent CLI on your Mac: Claude Code (claude), Codex (codex), or Grok (grok). Bloom uses the CLI you choose for each conversation. Git is required; GitHub CLI (gh) enables pull request and checks features. Cursor and OpenCode can be detected in Settings but cannot run conversations yet.

Bloom keeps its workspaces and conversation database on your Mac. It does not require a Bloom account. Agent CLIs use their own authentication and provider connections.

Work with Bloom

1. Add a Git repository as a project.
2. Create a workspace for a task. Bloom creates a branch and worktree, copies configured files, runs the project's setup script and starts the chosen agent. You can also open an existing branch or pull request, or start with a terminal.
3. Follow the conversation, inspect changed files and review the diff against the merge base. Open a terminal or browser beside the chat when you need one.
4. Create or merge a pull request from the workspace. Archive the workspace when the work is finished.

Workspaces live under ~/bloom/workspaces.noindex by default. The .noindex suffix keeps Spotlight from indexing every worktree. Bloom also supports multiple chats in one workspace, reusable quick prompts and subagents that work in the same branch. Conversation workspaces appear below projects in the sidebar and need no project, Git repository or worktree.

Useful shortcuts include Cmd+N for a new workspace, Cmd+J for a project-free conversation and Cmd+P to search files in the current project workspace. See the menu reference for the full list.

Incoming mails

The built-in inbox is enabled by default. Point your local app's SMTP host to 127.0.0.1 and port to 2255, with no encryption or authentication. Bloom Dev uses port 2256 so it can run beside the regular app. The inbox runs while Bloom is open and keeps its messages in Bloom's application data between launches. You can turn it off or change the SMTP port in Settings. The sidebar footer opens the message list. Agents running in Bloom can use its mail_send bridge tool to put plain text test messages in the same inbox, including from projects with no mail setup.

Browser access (alpha)

Browser access is in alpha and may change or be removed at any time. Bloom can show conversations in a browser while the Mac app is running. The browser can send prompts, create projects and workspaces, and inspect transcripts and file references. Some Mac features, including native diff review and terminal panes, are not available there yet.

On the same Mac, open Settings > Browser Access, enable Allow browser access, then choose Open in Browser. Bloom opens a one-use link, so you do not need to type an access code. Bloom Dev also accepts direct connections to http://127.0.0.1:53544 on the host Mac without a code.

To open Bloom from a phone or another computer through Tailscale:

1. Install Tailscale on both devices and sign in to the same tailnet. Keep Bloom running on the Mac.
2. In Bloom's Browser Access settings, enable access and expand Manual connection. Note the port in the address and use Copy Code for the access code.
3. In Terminal on the Mac, run tailscale serve --bg PORT, replacing PORT with the port from Bloom. For example, Bloom Dev uses tailscale serve --bg 53544.
4. Tailscale prints a private HTTPS address such as https://your-mac.your-tailnet.ts.net. Open it on the other device and enter Bloom's access code. Tailscale Serve keeps this address within your tailnet.

The hostname names your Mac in Tailscale, not a separate Bloom account. You can rename the Mac in Tailscale if you want a shorter hostname. The regular Bloom app chooses a new browser port and access code when it restarts. If the port changes, run tailscale serve --bg PORT again with the new port and use the new access code. Bloom Dev keeps port 53544, but its remote connections still require the code. To stop remote access, run tailscale serve off on the Mac or turn off browser access in Bloom.

Repository settings

Configure a project in .bloom/settings.toml. Put machine specific values in .bloom/settings.local.toml. Both can be edited from the project's settings screen. Supported settings include setup and archive scripts, named run scripts, files to copy, branch naming, the browser address and default models.

[scripts]
setup_file = ".bloom/setup.sh"
archive_file = ".bloom/archive.sh"

[browser]
url = "http://localhost:$BLOOM_PORT"

A script named by setup_file or archive_file runs in the worktree. Setup runs after creation; archive must succeed before Bloom removes the worktree. Inline scripts.setup and scripts.archive are also supported. Bloom supplies BLOOM_WORKSPACE_ID, BLOOM_WORKSPACE_PATH, BLOOM_ROOT_PATH, BLOOM_DEFAULT_BRANCH, BLOOM_PORT and other workspace variables.

A browser pane normally opens http://localhost:$BLOOM_PORT. Set browser.url as above or write an address to the file named by BLOOM_URL_FILE from your setup script. The file is ignored by Git and read when a browser pane opens.

Workspace agents can call project_setup_guide for the supported settings format and this copy of Bloom's current local SMTP port. Incoming mails is configured in Bloom Settings, not in the repository's .bloom/settings.toml.

Agent bridge

Workspace agents can ask Bloom to open panes, read the browser or terminal, show media, manage subagents and work with projects and workspaces through an MCP bridge. The bridge scopes a workspace agent to its own worktree. You can also register it in your own MCP client from Settings. See the bridge reference for tools and permissions.

Build from source

Install Xcode 26 and an agent CLI, then clone the repository:

git clone https://github.com/spatie/bloom.git
cd bloom
make dev-fast

This installs ~/Applications/Bloom Dev.app. The dev app has its own database, preferences and URL scheme, so it can run beside a released copy. make dev-fast builds current edits; make dev builds committed HEAD. Use ./Tools/dev-build.sh --fast --no-install to compile without installing or launching.

Package.swift is the Xcode entry point. There is no Xcode project. The architecture guide explains the BloomCore, Bloom and bridge targets. AGENTS.md indexes the project skills and CLAUDE.md contains the development rules shared by agents and contributors.

make build       # Compile all targets with warnings treated as errors
make lint        # Check project rules
make swiftlint   # Check Swift style

The core tests run through ./Tools/test-core.sh <filter> or make test. They do not compile the app target, so also run make build when changing code. Follow the local test guidance in CLAUDE.md when working on the owner's machine.

Documentation

• Architecture and contributing
• Agent integration
• Claude Code protocol, Codex protocol, Grok protocol
• MCP bridge
• Release process

Support and licence

Bloom is free, open source and postcardware. If you use it, send us a postcard from your hometown and tell us what you are building. We share them on our postcard wall. You can also support Spatie's open source work.

See CONTRIBUTING to contribute. Report security issues to security@spatie.be. Bloom is licensed under MIT.