codefission 0.1.6

Tree-structured AI coding assistant with git worktree isolation

CodeFission

Tree-structured AI coding assistant. Each conversation node is an isolated git worktree — branch conversations to explore alternative approaches, and each branch gets its own filesystem sandbox.

Prerequisites

• Python 3.12+ — install or via your package manager
• Claude Code — AI backend (spawned as subprocess). Install: npm install -g @anthropic-ai/claude-code
• git — worktree isolation. Usually pre-installed.

Authenticate Claude Code before first use:

claude login

Install

pip install codefission

Then run:

fission

Opens on http://localhost:8080. Use a different port: fission 3000.

Install from source

Requires uv and Node.js 20.19+ or 22.12+.

git clone https://github.com/codefission-ai/CodeFission.git
cd CodeFission
make install
fission

For development with auto frontend rebuild:

make dev

How it works

Create a tree in the sidebar, type a message, and CodeFission spawns a Claude Code session in an isolated git worktree. Branch any node to explore alternatives — each branch forks the conversation context and the filesystem state.

         [root]
        /      \
   [add auth]  [add auth]     <- same prompt, different approaches
      |            |
 [fix tests]  [add logging]   <- independent follow-ups

Every node tracks its git branch, commit, and Claude session. Child nodes fork from the parent's prompt cache so context carries over without re-sending history.

Authentication

Configurable in the Settings panel (gear icon in sidebar):

• CLI (OAuth) — default. Uses your claude login session. No API key needed.
• API Key — provide an Anthropic API key in settings. Useful for headless/remote setups.

Both modes require the Claude Code CLI binary to be installed.

Configuration

Open Settings (gear icon) to configure:

• Global defaults — provider, model, max turns, auth mode. Applies to all trees.
• Per-tree overrides — provider, model, max turns. Leave as "Default" to inherit global settings.

Settings persist in the backend database across sessions and devices.

Development

make dev          # install + build frontend + run server
make test         # run tests
make build        # build wheel for PyPI
make publish      # build + upload to PyPI
make clean        # remove build artifacts

Frontend dev server (hot reload):

cd frontend
npm run dev

Data is stored in ~/.codefission/ (SQLite database, git worktrees). Override with CODEFISSION_DATA_DIR env var.