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.
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.
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 https://deno.land/x/install/install.sh | sh
On Windows:
iwr https://deno.land/x/install/install.ps1 -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 1.25.3 (release, aarch64-apple-darwin)
v8 10.6.194.5
typescript 4.7.4
Ready to dive into development? Let's go!
Have 2 minutes to provide some feedback?
We'd love to hear about your experience building modular Slack apps. Please complete our short survey so we can use your feedback to improve.