Dire Wolf is a software Terminal Node Controller (TNC) for amateur radio packet radio, specifically AX.25 and APRS. It replaces hardware TNCs by demodulating audio from sound cards or SDR receivers, decoding AX.25 frames, and providing network interfaces (KISS, AGW) for client applications like Xastir, APRSIS32, and UI-View. The codebase is a monolithic C application with threaded audio capture, multiple modem demodulators (AFSK, PSK, G3RUH, 9600bps), forward error correction (FX.25, IL2P), digipeating, IGate (internet gateway), GPS integration, DTMF/APRStt gateway, and telemetry decoding. It runs on Linux, Windows, and macOS. The architecture is single-process with multiple threads, using a global event queue for inter-module communication. Key entry points include the main `direwolf` daemon and several standalone utilities (`decode_aprs`, `kissutil`, `gen_packets`, `atest`, etc.). The implementation is production-grade, with extensive protocol handling and real-world tuning, but exhibits some monolithic design patterns and legacy code (vendored regex, geotranz).