https://hackage.haskell.org/package/wiringPi-0.1.0.0 https://github.com/ppelleti/hs-wiringPi This is a Haskell binding to the wiringPi library, which allows you to interface with the GPIO pins on the Raspberry Pi. Unlike some other solutions for using the Raspberry Pi's GPIO pins, wiringPi provides access to more advanced features, such as enabling the internal pull-up or pull-down resistors. To use this library, you must either run as root, or set the WIRINGPI_GPIOMEM environment variable. (Set it to anything; the value does not matter.) However, PWM will not work if WIRINGPI_GPIOMEM is set. This library will only build on the Raspberry Pi. Before building this library, you must install the "wiringPi" C library on your Raspberry Pi, like this: sudo apt-get install wiringpi Tested on a Raspberry Pi Model B, with Raspbian Jessie Lite, using the system-provided Haskell compiler. (GHC 7.6.3.) This Haskell binding is licensed under the 3-clause BSD license, and the examples in the examples directory are in the public domain. However, be aware that the wiringPi C library itself is licensed under the LGPLv3+. --Patrick