Alf.io

Alf.io is an open source ticket reservation and event attendance management system for event organizers. It covers the full lifecycle from ticket sales and payments to check-in operations and reporting, with a strong focus on privacy and security.

Key Features

• Public ticket shop for ticket reservation and sales
• Backoffice/admin area for event setup and management
• Payment gateway integrations including Stripe, PayPal, Mollie, Revolut, and bank transfer options
• Reporting capabilities across the event lifecycle
• Extension mechanism to integrate with third-party tools (for example CRM systems)
• Mobile apps (iOS and Android) for attendee check-in and sponsor/exhibitor lead capture
• High-throughput, offline-capable check-in station support (including Raspberry Pi setups with encrypted attendee lists)
• Multi-language user interface

Use Cases

• Running ticketing and check-in for conferences, trade shows, workshops, and meetups
• On-site badge scanning and lead collection for sponsors/exhibitors
• Offline check-in and badge printing workflows for high-volume events

Limitations and Considerations

• Requires PostgreSQL (10+) and a Java 17 runtime for deployment
• Some payment methods require third-party accounts and configuration with their providers

Alf.io is suited for organizations that want control over event data and ticketing costs while still offering modern payment and check-in workflows. Its modular integrations and offline-capable check-in options make it practical for both small meetups and larger events.