The Nucleo boards work with a wide range of IDEs (Integrated Development Environment) including IAR EWARM, Keil’s MDK and GCC-based IDEs like Atollic. It is also important to note that they do work with mbed. Mbed is ARMs free online development environment which is low cost and easy to use. The boards themselves come with some preloaded, simple software allowing a demo which flashes the LEDs. Additionally, there is going to be various examples that come with the board that use some Arduino shields so that LCD and joysticks can be used. The library support covers the standard library, the STM32 queue and support for the mbed core.