Twenty

Twenty is an open source customer relationship management platform that originally launched as a modern alternative to tools like Salesforce or HubSpot. It includes billing automation capabilities directly inside the CRM workflow, letting teams manage subscriptions, invoices, and payment collection without stitching together separate tools.

The platform integrates with Stripe for payment processing and offers a GraphQL API for custom integrations. It runs as a web application with a React frontend and a Node.js/TypeScript backend. You can self-host Twenty on your own infrastructure or use their cloud-hosted version. The database layer uses PostgreSQL, and the application supports Docker-based deployment for easy setup on Linux servers.

Twenty is developed by Twenty SAS, a French company. The software is released under the AGPLv3 license for self-hosted users, with a commercial license available for managed cloud usage. It's a good fit for small to mid-sized businesses that want an open source CRM with billing features baked in rather than paying for separate subscription management software.