The OpenPLC is a opensource Programmable Logic Controllers (PLC) alternative. Due to this, it is possible to understand the black box of these systems. It could be easily used with a Raspberry Pi.
The Mirai source code reveals the passwords, which are used to create the botnet. These passwords should never ever be used to secure a device.
In my part time I have done my first Offensive Security course and certificate. It is called Wireless Attacks (WiFu) and deals with all kind of wireless attacks.