This is a simple program that will allow you to control a string of ws2812 leds via serial / uart using an esp8266. This could be used to control RGB leds from a PC, or in my case, via the UART port ...

Arduino Library for RGB LED Bonezegei WS2812 is an Arduino library for controlling WS2812 or WS2812B RGB LED strips, single LEDs, or matrices. WS2812 LEDs are addressable LEDs that have an integrated ...

Beyond the strip of WS2812 LEDs, all you really need is a microcontroller and two buttons. Here [mircemk] is using an Arduino Nano, but you could press pretty much any MCU into service.