Hands-On Demo: Get your laptops out! It’s time to roll up your sleeves and get your hands dirty with a real-life computational-law language, L4. Participants will learn the syntax and semantics of a particular computational-law language by encoding a simple piece of legal text; setting up the IDE; writing your first simple program; demo applications and integrations; we visit a walkthrough of the source code of an insurance contract, some privacy regulation, and a loan agreement; regenerating natural language text. Could it be possible for L4 to act as a bridge, for interoperability, between all the languages we have seen today? We begin the session with a few demos of data visualization, formal verification, and transpilation from L4.