ZNC

ZNC is a self‑hosted IRC bouncer that stays connected to IRC networks while individual clients disconnect and reconnect, preserving nicknames, operator status and channel buffers. Users configure a central server, then connect their IRC clients to it, optionally using the built‑in web interface or IRC commands to manage settings, add users, and select networks. The software supports per‑user buffering of channel messages, with options to retain or discard buffers after replay, and can handle multiple simultaneous users and networks under a single process.

The project is written in C++ and can be extended through dynamically loaded modules written in C++, Perl, Python or Tcl, allowing custom functionality such as client‑side buffering or channel filtering. It offers optional SSL/TLS encryption, character‑set handling via ICU, internationalisation with Boost.Locale and gettext, and Argon2 password hashing. Build requirements include GNU make, CMake, GCC or clang, and optional libraries for SSL, Perl, Python, Cyrus SASL, and ICU.

ZNC is released under the Apache‑2.0 license, is considered stable, and is available for free without subscription. It can be compiled from source using CMake or the legacy configure script, and pre‑built packages exist for many Linux distributions, FreeBSD and Windows. The default data directory stores configuration and buffers, while modules reside in the installation prefix.