But Deno is not a monolithic program, but designed as a collection of Rust crates to allow integration at different layers.
Deno is not compatible, in general, with Node (NPM) packages. There is a nascent compatibility layer being built at https://deno.land/std/node/ but it is far from complete.
Deno supports TypeScript without additional tooling. The runtime is designed with TypeScript in mind. The
deno typescommand provides type declarations for everything provided by Deno. Deno’s standard modules are all written in TypeScript.