The Radix Engine Toolkit (RET) is available for a number of different languages: TypeScript, Python, Swift, C#, Kotlin (JVM) and Rust. It is a library for building Radix Transactions.
The Typescript toolkit is particularly useful, as it includes an “LTS” interface. This offers a simplified API designed for exchanges and is available in Typescript for running in NodeJS. Examples in the rest of this document will be written assuming the TypeScript LTS RET is being used.