openwandb 0.5.25

Open-source WandB-compatible server with multi-tenant support

OpenWandb

Open-source, self-hosted WandB (Weights & Biases) compatible server — a drop-in replacement for the proprietary wandb server, designed for private deployment.

Just set WANDB_BASE_URL and your existing training scripts work seamlessly with your own server — zero code changes required.

If you find OpenWandb useful, please consider giving it a star on GitHub — it helps others discover the project!

Why OpenWandb?

	wandb Cloud	OpenWandb
Pricing	Free tier limited; paid plans per user	Free forever
Data location	wandb servers (US)	Your own server
Privacy	Data uploaded to third party	100% on-premise
Setup	Create account, get API key	pip install openwandb && openwandb serve
Code changes	None	None — just change WANDB_BASE_URL
User limits	Varies by plan	Unlimited
Run limits	Varies by plan	Unlimited
Storage	Limited by plan	Limited by your disk
Offline/Air-gapped	No	Yes
Custom deployment	No	K8s, Docker, bare metal, NFS
Multi-tenant	Enterprise only	Built-in

Features

• Fully compatible with wandb Python SDK — implements GraphQL API + File Stream protocol
• One-command deployment — pip install openwandb && openwandb serve
• Built-in CLI — openwandb serve / init / demo / version
• Multi-tenant isolation — Team → Project → Run three-level permission hierarchy
• User management — Registration/login, JWT + API Key dual authentication
• Team collaboration — Create teams, invite members, role management (Owner/Admin/Member/Viewer)
• Sharing — Project/run-level token-based share links
• Web dashboard — Dark-theme UI with ECharts visualization engine
• Zero configuration — SQLite database + local file storage, no Docker/K8s required
• PostgreSQL support — Optional PostgreSQL backend for production scale
• Reverse proxy ready — Full support for K8s ingress / Nginx with path prefixes
• Media & Artifacts — wandb.Image, wandb.Table, wandb.Artifact all supported

Quick Start

Install from PyPI (recommended)

pip install openwandb

# Start the server (data stored in ~/.openwandb/ by default)
openwandb serve

# Customize port and data directory
openwandb serve --port 9090 --data-dir /data/openwandb

Install from source (development)

git clone https://github.com/CVPaul/OpenWandb.git
cd OpenWandb

# Editable install
pip install -e .
openwandb serve

# Or run directly (data stored in ./data/)
python run_server.py

The server runs at http://localhost:8080 by default. Default admin credentials: admin / admin123 (change via environment variables in production).

Configure your training script

Set two environment variables and run your training script as usual:

export WANDB_BASE_URL=http://localhost:8080
export WANDB_API_KEY=local0000000000000000000000000000000000000000

import wandb

wandb.init(project="my-project", config={"lr": 0.001})

for step in range(100):
    loss = train_step()
    wandb.log({"loss": loss, "accuracy": acc}, step=step)

wandb.finish()

Run the built-in demo

OpenWandb ships with a full MNIST demo that showcases all wandb features:

# Default mode: pure NumPy (no PyTorch needed!)
openwandb demo

# PyTorch Lightning mode
openwandb demo --lightning

# Customize runs and epochs
openwandb demo --runs 5 --epochs 50

The demo showcases: wandb.log(), wandb.Image, wandb.Table, wandb.Artifact, namespace grouping, multi-run comparison, and more.

Manage API Keys

1. Log in to the Web UI → Settings → API Keys
2. Create a new API Key
3. Use the new key in your scripts:

   export WANDB_API_KEY=local-xxxxxxxxxxxxxxxxxxxx
   

CLI Reference

# Start the server
openwandb serve [OPTIONS]
  --host TEXT          Bind address (default: 0.0.0.0)
  --port/-p INT        Port (default: 8080)
  --data-dir PATH      Data directory (default: ~/.openwandb)
  --log-level TEXT     Log level: debug/info/warning/error
  --reload             Enable auto-reload (dev mode)
  --root-path TEXT     URL path prefix for reverse proxy
  --base-url TEXT      Full external URL override for file uploads
  --db TEXT            Database backend: sqlite/postgres
  --pg-url TEXT        PostgreSQL connection URL

# Initialize data directory and database
openwandb init [--data-dir PATH] [--pg-url URL]

# Run MNIST demo
openwandb demo [--lightning] [--runs N] [--epochs N] [--no-run]

# Show version
openwandb version

# Also supports python -m
python -m openwandb serve

Multi-Tenancy

Create a team

1. Log in → Settings → Teams → Create New Team
2. Invite members to the team
3. Set member roles (Viewer / Member / Admin)

Team projects

Specify the team via the entity parameter in wandb SDK:

wandb.init(project="my-project", entity="my-team")

Project visibility

Visibility	Description
Private	Only the creator can access
Team	Team members can access (default)
Public	Everyone can access

Sharing

Click the "Share" button on any project or run page to generate a public link. Anyone with the link can view (read-only).

Configuration

All settings are configurable via environment variables:

Variable	Default	Description
OPENWANDB_DATA_DIR	~/.openwandb	Data storage directory
OPENWANDB_HOST	0.0.0.0	Bind address
OPENWANDB_PORT	8080	Listen port
OPENWANDB_JWT_SECRET	Random	JWT signing secret
OPENWANDB_JWT_EXPIRE_HOURS	72	JWT expiration (hours)
OPENWANDB_ADMIN_USER	admin	Default admin username
OPENWANDB_ADMIN_PASS	admin123	Default admin password
OPENWANDB_DEFAULT_TEAM	default	Default team name
OPENWANDB_ALLOW_REGISTRATION	true	Allow new user registration
OPENWANDB_MAX_FILE_SIZE	500MB	Maximum file upload size
OPENWANDB_LOG_LEVEL	INFO	Log level
OPENWANDB_DB_BACKEND	sqlite	Database backend (sqlite or postgres)
OPENWANDB_PG_URL		PostgreSQL connection URL
OPENWANDB_ROOT_PATH		URL path prefix for reverse proxy
OPENWANDB_BASE_URL		Full external URL override for uploads

Deployment

Basic (single machine)

pip install openwandb
openwandb serve --port 8080 --data-dir /data/openwandb

With PostgreSQL

openwandb serve --pg-url postgresql://user:pass@db-host:5432/openwandb

Behind a reverse proxy (Nginx / K8s Ingress)

When deploying behind a reverse proxy with a URL path prefix:

# The server auto-detects the prefix from X-Forwarded-* headers
openwandb serve --root-path /my/prefix

K8s deployment example:

containers:
  - name: openwandb
    image: python:3.12-slim
    command: ["openwandb", "serve", "--root-path", "/my/prefix"]
    env:
      - name: OPENWANDB_DATA_DIR
        value: "/data/openwandb"
      # Optional: override upload URL if headers aren't forwarded correctly
      # - name: OPENWANDB_BASE_URL
      #   value: "https://my-domain.com/my/prefix"

The server automatically distinguishes between direct SDK access (internal service) and browser access (through ingress) to generate correct file upload URLs.

Diagnostic endpoint

Use the built-in debug endpoint to verify reverse proxy configuration:

GET /api/v1/debug/headers

Returns the computed base URL, detected headers, and proxy status.

API Endpoints

wandb SDK compatible endpoints

Endpoint	Description
POST /graphql	GraphQL API (wandb SDK core communication)
POST /files/{entity}/{project}/{run}/file_stream	Metrics stream upload
GET /files/{entity}/{project}/{run}/{filename}	File download
PUT /files/{entity}/{project}/{run}/{filename}	File upload

Authentication API

Endpoint	Description
POST /api/v2/auth/register	User registration
POST /api/v2/auth/login	User login (returns JWT)
POST /api/v2/auth/logout	User logout
GET /api/v2/auth/me	Get current user info

Team Management API

Endpoint	Description
GET /api/v2/teams	List my teams
POST /api/v2/teams	Create a team
GET /api/v2/teams/{name}/members	List members
POST /api/v2/teams/{name}/members	Invite member
PUT /api/v2/teams/{name}/members/{uid}	Update role
DELETE /api/v2/teams/{name}/members/{uid}	Remove member

API Key Management

Endpoint	Description
GET /api/v2/settings/api-keys	List my API keys
POST /api/v2/settings/api-keys	Create new key (returns plaintext once)
DELETE /api/v2/settings/api-keys/{id}	Delete key

Sharing API

Endpoint	Description
POST /api/v2/share	Create share link
GET /api/v2/share/{token}	Access via token
DELETE /api/v2/share/{id}	Revoke share link
GET /s/{token}	Share link entry (auto-redirect)

Internal REST API

Endpoint	Description
GET /api/v2/projects	List projects (filtered by permission)
GET /api/v2/projects/{entity}/{project}/runs	List runs
GET /api/v2/runs/{run_id}/metrics	Get metric data
GET /api/v2/runs/{run_id}/system_metrics	Get system metrics
PUT /api/v2/projects/{id}/visibility	Update visibility

Web Dashboard

Page	Features
Home	Project list, team switcher, search, stats overview
Project	Run list, status filter, sort, share, visibility control
Run Detail	Metric charts, config viewer, summary, system monitoring, media
Run Compare	Multi-run metric overlay, hyperparameter diff
Login/Register	User login, new user registration
Settings	Profile, API key management, team list
Team	Member list, invite, role management, team projects

Permission Model

Team (Organization)
├── Owner   — Full control (delete team, manage roles)
├── Admin   — Manage members (invite/remove)
├── Member  — Read/write (create projects, log runs)
└── Viewer  — Read-only (view projects and runs)

Project
├── Private  — Creator only
├── Team     — Team members (default)
└── Public   — Everyone

Run → Inherits permissions from its parent project

Architecture

┌──────────────────┐         ┌──────────────────────────┐
│  wandb Python SDK │ ──────> │     FastAPI Server        │
│  (training script)│  HTTP   │                          │
└──────────────────┘         │  ┌── Auth Middleware ──┐   │
                             │  │ JWT + API Key       │   │
┌──────────────────┐         │  └─────────────────────┘   │
│  Web Dashboard    │ ──────> │                          │
│  (browser)        │  HTTP   │  ┌── GraphQL ──────────┐  │
└──────────────────┘         │  │ Strawberry GraphQL   │  │
                             │  │ (wandb SDK compat)   │  │
                             │  └──────────────────────┘  │
                             │  ┌── REST API ──────────┐  │
                             │  │ Auth / Teams / Share  │  │
                             │  │ Projects / Runs       │  │
                             │  └──────────────────────┘  │
                             │         │                  │
                             │    ┌────▼────┐             │
                             │    │ SQLite  │  (or Postgres)
                             │    │ + Files │             │
                             │    └─────────┘             │
                             └────────────────────────────┘

Project Structure

open-wandb/
├── pyproject.toml             # Package config (hatchling)
├── run_server.py              # Dev mode startup script
├── examples/
│   ├── example_train.py       # Mock training example
│   └── example_mlp.py         # MNIST MLP training example
├── openwandb/                 # Python package
│   ├── __init__.py            # Version
│   ├── __main__.py            # python -m openwandb
│   ├── cli.py                 # CLI commands (serve/init/demo/version)
│   ├── config.py              # Configuration (paths/env vars)
│   ├── server.py              # FastAPI main app + all routes
│   ├── database.py            # DB dispatcher (SQLite/Postgres)
│   ├── _db_sqlite.py          # SQLite backend
│   ├── _db_postgres.py        # PostgreSQL backend
│   ├── graphql_schema.py      # GraphQL schema (wandb SDK compat)
│   ├── file_stream.py         # File stream handler
│   ├── storage.py             # File/artifact storage
│   ├── auth.py                # JWT + API Key authentication
│   ├── templates/             # Web UI templates (7 pages)
│   └── static/                # CSS + JS assets
├── tests/                     # Test suite
└── LICENSE                    # CC BY-NC 4.0 License

Contributing

Contributions are welcome! Please follow these steps:

1. Fork the repository
2. Create a feature branch: git checkout -b feature/your-feature
3. Commit your changes: git commit -m 'Add your feature'
4. Push to the branch: git push origin feature/your-feature
5. Open a Pull Request

Development setup

git clone https://github.com/CVPaul/OpenWandb.git
cd OpenWandb
pip install -e ".[dev]"
pytest

License

This project is licensed under CC BY-NC 4.0 — free for non-commercial use. Commercial use requires a separate license agreement.