Celerp

Free business management software for you and your office. Setup in minutes. Easy enough for solo entrepreneurs and powerful enough for large enterprises

Inventory, invoicing, purchasing, consignment, manufacturing, accounting, and CRM - in one app, on your computer. No subscription. No cloud required.

Website: www.celerp.com

Celerp is simple to use, flexible, customizable, and designed to transition your business into the AI age with no technical knowledge needed to setup your whole office. We want to put businesses back in charge of their data.

Screenshots

Real double-entry accounting, multi-location inventory, manufacturing, and a built-in REST API - one self-hosted app.

Trial balance - ties out to zero	Balance sheet - live from the ledger
General ledger - full drill-down	Inventory - multi-location, barcode, valuation
Production planning - work orders, priorities, due dates	REST API - integrate anything
Dashboard - revenue trend, AR aging, inventory mix

More in the press kit.

Install

Double-click. No account. No credit card. Your computer securely becomes the server for your office

Or install via pip:

pip install celerp
celerp init        # sets up the database and launches Celerp

Open http://localhost:8080. Done. Your office can securely access the system at your IP address :8080.

No PostgreSQL to install: celerp init uses your existing PostgreSQL server if one is running, and otherwise starts a self-contained bundled database — no sudo, no system service. Point it at a specific server with celerp init --db-url postgresql+asyncpg://….

Running headless or under a process manager? Use celerp init --no-start to set up without launching, then have your service run celerp start — see Run as a service (systemd).

What's inside

• Track inventory across locations, scan barcodes, print labels
• Send invoices, purchase orders, quotations, credit notes
• Double-entry accounting with chart of accounts, P&L, balance sheet
• Connect Shopify, WooCommerce, QuickBooks, Xero
• Manufacturing - BOMs, production orders, merge/split/transform
• CRM - contacts, pipeline, memos, activity feed
• Recurring subscriptions with automatic invoicing
• CSV import/export everything - idempotent, audited, column-mapped
• Multi-company from one install
• Role-based permissions - five access levels (viewer, operator, manager, admin, owner) for controlled employee access
• Works offline, no internet required

How it works

Celerp runs entirely on your machine. Your data never leaves your computer.

• No setup - the desktop app bundles Postgres, runs migrations on launch, opens in your browser
• No lock-in - your data stays in a standard Postgres database you control
• Teams - run as a local server, teammates connect over the LAN

Modules

Every business domain is a self-contained module. The full set ships with the download:

The onboarding wizard lets you pick your industry. Modules can be toggled any time at Settings > Modules.

Build your own

Every feature above is a module on one loader API, and you can build against the same API. A module is a Python package you drop into Celerp's modules/ folder; it adds its own tables, API routes, and UI pages, no fork or build step.

• celerp-module-template - a working example module you can run in about ten minutes, plus a lint script
• Build a module - the guide
• community-modules - a directory of community-built modules, and how to list yours

Architecture

• Event-sourced - every change is an immutable ledger entry, projections materialize queryable state
• Modular - each domain is a plugin with its own models, routes, and projections
• Python/FastAPI backend, FastHTML UI, embedded PostgreSQL
• SQLite in-memory for tests - no external dependencies to run the test suite

Development

git clone git@github.com:celerp/celerp.git
cd celerp
python3 -m venv .venv && source .venv/bin/activate
pip install -e ".[dev]"
celerp init   # creates DB, runs migrations, starts servers

celerp init boots a bundled PostgreSQL when no server is running, so no sudo and no system Postgres are required. To develop against your own server instead, pass --db-url postgresql+asyncpg://….

Open http://localhost:8080. Run tests with pytest tests/.

See CONTRIBUTING.md for environment variables, troubleshooting, and coding guidelines.

Contributing

Issues and PRs welcome. The module system makes it straightforward to add new business domains without touching the kernel.

License

Free to download. Free to self-host. Free to build on.

Celerp is open-core:

• Source-available core engine under the Business Source License 1.1 - self-hosting permitted, contributions welcome.
• An MIT-licensed module ecosystem - the default business modules are MIT, so you can fork them, build your own modules, and ship them however you like. See LICENSING.md.
• A proprietary application + cloud layer (official UI, document/PDF output, and the cloud/AI services) that powers the hosted experience.

See LICENSING.md for the full map and TRADEMARK.md for use of the Celerp name. One restriction: don't resell Celerp itself as a competing product.