Mongoose
A two-file embeddable C/C++ network library providing a full stack of HTTP, WebSocket, MQTT and TLS for microcontrollers and desktop operating systems alike.
Mongoose is an embedded web server and network library distributed as just two files, mongoose.c and mongoose.h, that can be dropped into any C or C++ project to add a network stack covering HTTP, WebSocket, MQTT, TLS and firmware over-the-air updates, plus a device dashboard.
It runs on Linux, macOS, Windows and a wide range of microcontrollers, including STM32, NXP, ESP32, Nordic, TI, Microchip, Infineon and Renesas chips, and can use its own built-in TCP/IP stack for bare-metal or RTOS environments or run on top of an existing stack such as lwIP or Zephyr.
Built-in TLS 1.3 support is included, with the option to use external libraries like mbedTLS or OpenSSL instead, and the library has no other software dependencies for its networking.