Install Deno

As we previously covered, Deno is a runtime that executes programs written in JavaScript, TypeScript, and WebAssembly. So, if you know how to write apps in one of those languages (or would like to!) Deno is how you will execute your app.

If you've written JavaScript for web browsers before, everything will feel very familiar. If you've written JavaScript or TypeScript for web servers before, probably using Node.js as your runtime, most things will feel familiar with a few key differences.

Differences with Node.js

The biggest reason you may not want to move your existing Node.js-based applications to Deno is npm modules aren't yet fully supported. The vast ecosystem of modules that have been built over the years aren't guaranteed to work with your application by default. The Deno team is working on some approaches to allowing npm modules, including the built-in standard library that should obviate the need for many npm modules, and CDNs that host npm modules in a way that Deno can use. That said, not every npm module will work with Deno automatically, particularly more complex libaries, so you may need to wait on a rewrite or roll your own.

Installing Deno

Deno ships as a single executable with no external dependencies. Versions are available for macOS (both Intel and Apple silicon architectures), Linux, and Windows (64-bit support only for Linux and Windows).

The easiest way to install is to call the deno_install script remotely.

On macOS and Linux:

curl -fsSL | sh

On Windows:

iwr -useb | iex

The official installation guide provides details for various other platforms. As Deno is open source, you are free to compile from source as well.

Once installed, run deno --version to verify the installation was succesful. The output should look something like the following:

$ deno --version
deno 1.31.1* (release, x86_64-apple-darwin)
v8 10.*
typescript 4.*

The minimum version of Deno runtime required for developing on the next-generation platform is currently at version 1.37.0.

Installing the Deno extension for VSCode

The installation script from our Quickstart guide should cover everything for you, but if you want to manually install the vscode_deno extension, follow these steps:

  1. Within VSCode, select Extensions from the sidebar.
  2. Enter Deno in the search bar.
  3. Select Deno (a language server client for Deno, published by and Install.

Alternatively, you can download and install the extension from here.

Once installed, you should see a splash screen welcoming you to the extension. For additional information about configuring the extention, refer to Using Visual Studio Code.


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