SSokit

SSokit is a macOS‑only utility for debugging TCP and UDP communication. It can act as either a server or a client, allowing users to send and receive raw network packets through a graphical interface. The tool supports both protocols and displays traffic in real time, making it suitable for inspecting connection behavior and data flow.

A notable feature is the ability to configure custom packet headers. Users can prepend a header to outgoing messages, entering values as hexadecimal or ASCII. The header can optionally include the length of the payload and any trailing data, with selectable field sizes (none, 2‑byte short, or 4‑byte integer) and byte‑order (big‑endian or little‑endian). These options are exposed through an advanced settings pane.

Installation is straightforward for macOS users via Homebrew Cask. The project is maintained as a stable release and accepts feedback through its issue tracker and a contact channel.