The popularity of data- and scientific-oriented applications, abundance of on-demand compute resources, and scarcity of domain expert programmers have given rise to high-level scripting languages. These high-level scripting languages offer a fast way to translate ideas into code, but tend to incur a heavy performance overhead. In order to alleviate the performance penalty, each implementation of these languages often offers a compilation path to a subset of the language. In this paper we present the design and implementation of theWolfram Language compiler, the production compiler for the Wolfram Language. We show how popular language features and runtime behavior, expected by Wolfram Language developers, are efficiently implemented within the compiler. We then show how the compiler provides a friction-less path to migrate programs from the interpreter to the compiler.We evaluate the compiler and show that compiled code matches the performance of highly tuned hand-written C code. The compiler has been released as a prominent feature of Wolfram Engine v12 and is readily available to developers.