The core of LISA is a rest API to extend the power of home automation box with python code. Around this API, there's few components to add natural language (voice and text) to communicate with the API, and a web interface to manage L.I.S.A.
Python is really easy to learn, write and understand. The code is well documented and easy to understand
LISA has always been Open Source (and will always be) and all the source code is available on Github
LISA employees best-in-class technologies such as Django, RabbitMQ, MySQL, Websockets, REST Framework ...
From the ground up, with many plugin hooks, LISA is extremely extensible and modular to let you install only what you need