Alarmthat

Alarmthat is an open-source, cross-platform alarm and notification system designed to coordinate alerts across devices and services. It lets users set alarms and reminders that trigger across multiple channels, including audio on local devices, push notifications, email, and SMS, and can be extended via APIs and webhooks.

Key features include time-zone aware scheduling, recurring alarms, calendar integrations, templates for alert messages, multi-channel delivery, a web-based dashboard, mobile clients, a REST API, and a plugin architecture for integrations with third-party services.

Architecture-wise, the system follows a client-server model with a central server storing alarm definitions and delivery rules, a web dashboard for management, and lightweight agents or clients on devices to receive or trigger alarms. It supports offline operation and uses message queues to manage deliveries, with secure communication protocols.

History and development reflect its origins in the open-source community in the early 2020s, focusing on privacy, configurability, and interoperability. It is maintained by a volunteer team with community governance and regular releases.

Impact and reception emphasize its use by individuals, educational settings, and small teams seeking a flexible alerting solution. Reviews have highlighted its extensibility and multi-channel support, while critics note that some initial setup can be challenging for non-technical users. The project is released under an open-source license on a public repository.