MQTTS is a MQTT library. It currently supports MQTT 3.1.1 but may support MQTT 5 in the future.

These are the key features:

• Multiple Transports (TLS, TCP, more to come)
• Focus On Extensibility
• Written in Typescript
• Parameterized listeners: devices/:name/color will also give you any object with the properties: {name: '...'}

Check out the example.