ble-host
A full-featured Bluetooth Low Energy (BLE) host stack written in JavaScript that lets you set up and program peripherals and centrals.
hci-socket
Linux bindings for using a Bluetooth controller in Node.js over HCI.
safecolor
SafeColor generates accessible colors that compiles with WCAG success criteria 1.4.3 (or any contrast ratio of your choice). It can generate either a random color that is contrast safe with a given color, or a consistent color for a given string.