This project was a request by my team leader for a small STM32 module. As Nucleo 32 doesn't have enough pins for our application, we decided to create our own module similar to Arduino Nano and utilize the STM32F303CC MCU. This one in the picture is using this MCU. However, you can use other STM32F or STM32L MCU as long as it has QFP-48 Package. 

Note:  The one in the photo is actually altered to use pin PA11 and PA12 to CAN Transceiver mounted underneath for our team application. The design files I published here does not have that Transceiver and exposed these pins to the headers as not a lot of other projects use CAN Bus.