Argon — Git for MongoDB

Branch, time-travel, merge and undo your MongoDB. Any driver, real mongod, versioned history underneath. Built for AI agents.

Three ideas, thirty seconds:

1. A branch is a pointer, not a copy — created with a metadata write. Checkout separately materializes the data.
2. checkout turns a branch into a real MongoDB database — pymongo, mongoose, mongosh, indexes, aggregation, transactions: all real, and supported document writes become history while capture is healthy.
3. Review and recover changes — diff, merge, undo and pin states within the configured retention and capture guarantees.

Install

brew install argon-lab/tap/argonctl      # macOS
npm install -g argonctl                  # cross-platform

# MongoDB must run as a replica set (one-node is fine):
docker run -d --name argon-mongo -p 127.0.0.1:27017:27017 mongo:7 --replSet rs0
docker exec argon-mongo mongosh --quiet --eval 'rs.initiate({_id:"rs0",members:[{_id:0,host:"localhost:27017"}]})'
argon doctor

Use a current supported MongoDB patch release in production. Source builds use Go 1.26.6 or newer, as declared in go.mod.

The flow

main ──branch──▶ experiment ──checkout──▶ mongodb://…  ← any driver
                                              │
                     ┌── argon diff ──────────┤  document history
                     ▼                        ▼
        merge (a data PR)          or   undo / discard / rewind

# 0 · Bring your data in ("git clone") — or: argon projects create myapp
argon import database --uri mongodb://localhost:27017 --database myapp --project myapp

# 1 · Branch — instant, no copy
argon branches create experiment -p myapp

# 2 · In terminal A, capture writes with a branch actor label
argon checkout -p myapp -b experiment      # prints a connection string
argon watch    -p myapp -b experiment --actor agent:experiment

# In terminal B, write through the printed URI. Then:

# 3 · Review and merge back — a data pull request
argon diff          -p myapp -b experiment
argon merge preview -p myapp -b experiment
argon merge apply <plan-id>

# …or rewind instead of merging
argon restore reset -p myapp -b main --time 2026-07-07T09:00:00Z --backup pre-incident

Prefer clicking? argon console serves a local web console (UI + REST API), supervises capture, reaps expired sandboxes every minute, and opens your browser. For a complete managed workflow, run the two-agent pinned dataset example.

What you get

	Command	In one line
Branching	argon branches create	a metadata write — instant, zero copy
Real databases	argon checkout / argon proxy	any driver, real mongod; proxy serves stable mongodb://host/<project>~<branch> URIs
Write capture	argon watch	exact change-stream images → history, one actor label per branch
Time travel	argon time-travel query	any historical state, by LSN or timestamp
Undo	argon undo --actor <a>	revert a range or actor label; append-only, conflict-aware
Restore	argon restore preview/reset/branch	rewind a released branch or fork retained history
Data PRs	argon merge preview/apply	three-way merges as reviewable plans; conflicts never silent
Sandboxes	argon sandbox create --ttl 1h	fork + checkout + TTL in one step — disposable agent workspaces
Dataset pins	argon pin create / pin sandbox	immutable named states that survive GC and resets — reproducible evals
Web console	argon console	local UI + REST API in one command

Data history covers document inserts, updates, replacements and deletes. Collection drop/rename produces degraded capture; indexes and collection options are not versioned. Native writes are asynchronous; control operations drain capture. Stop writers before release. Pins preserve states, while GC can expire audit and undo history. See operations for recovery and credentials.

Storage retention uses snapshots + retention-window GC keep state plus a window of history, not every write forever. Details and the consistency model, stated honestly: ARCHITECTURE.md.

For AI agents

claude mcp add argon -- argon mcp        # 13 tools: sandbox, diff, merge, undo, pins
pip install argon-agents                 # LangGraph checkpointer + Mem0, over REST

saver = ArgonCheckpointSaver.from_sandbox(argon, "myapp")   # checkpoint on a disposable branch
saver.merge()                                               # adopt the run — or .discard()

argon.create_pin("myapp", "eval-v1")                        # pin the dataset once
run = argon.sandbox_from_pin("myapp", "eval-v1")            # identical state, every eval run

The full agent workflow: docs/AGENTS.md.

Documentation

Quick start	install → first merge, step by step
CLI reference	every command
Agents	sandboxes, pins, MCP, REST API, argon-agents, proxy
Architecture	how it works and what it guarantees
Operations	deployment, chunk stores (S3/FS), GC, v1→v2 migration
Performance	every number lives in the reproducible benchmarks — none here, by policy

Community

Issues · Discussions · Contributing · argonlabs.tech

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Give your MongoDB a time machine. Branch without fear. ⭐