FHEM is an open-source Perl-based server for home automation. It runs as a background service and provides device control and monitoring via built-in web frontends, smartphone apps, telnet, or TCP/IP. It supports a wide range of hardware protocols through a modular collection of modules.

Key Features

Modular architecture with hundreds of modules to support a wide range of devices and services.
Multiple frontends and interfaces, including web, mobile frontends, telnet, and TCP/IP, with JSON/XML support.
Autocreating devices and logs as new data arrives, reducing manual setup.
Flexible logging options (files or databases) with optional filters.
Event-driven automation: trigger external programs or scripts on device events.
Timed and scheduled commands and time-based actions (e.g., lights based on sunset).
Active community, comprehensive documentation, and a development repository.

Use Cases

Automate household tasks such as lighting, blinds, heating, and sensor monitoring.
Integrate with a broad set of protocols and devices (HomeMatic, KNX, Z-Wave, EnOcean, etc).
Run on a self-hosted server (e.g., NAS, Raspberry Pi) with local data storage for privacy.

FHEM is a long-running, Perl-based home automation server with broad device support and a modular, pluggable architecture.