Tree-structured AI coding assistant. Each conversation branch gets its own isolated git worktree — explore alternatives without losing progress.
[root] / \ [add auth] [add auth] ← same prompt, different approaches | | [fix tests] [add logging] ← independent follow-ups
Traditional AI chat is linear. CodeFission gives you a tree — branch any conversation to try a different approach, and keep both.
Every message is a node. Branch from any point to explore alternatives. Your conversation history becomes a visual tree you can navigate.
Each branch runs in its own git worktree with a separate filesystem. Changes in one branch never affect another.
Child nodes fork their parent's session — reusing the prompt cache. Branching is fast and cost-efficient.
See your entire exploration as an interactive map. Zoom, pan, and click any node to jump back to that point in the conversation.
Browse files in any node's workspace. View diffs between parent and child to see exactly what the AI changed.
Your code stays on your machine. CodeFission runs as a local server — no data leaves your laptop except API calls to Claude.
Start a conversation, branch when you want to try something different, and compare results across branches.
Start a new project or import an existing repo. CodeFission initializes a git repo and sets up the root workspace.
Ask Claude to write code, fix bugs, or build features. It works directly in an isolated filesystem with full tool access.
Not sure about the approach? Branch the conversation. Each branch gets its own worktree forked from that point in time.
View diffs, browse files, and compare results across branches. Continue down whichever path worked best.
Requires Node.js, Python 3.11+, and
uv.
Authenticate with claude login or
set an API key in settings.