What is Deno?

Get introduced to Deno and learn the differences between Deno and Node.js.

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Deno (pronounced “dee-no”) was created by Ryan Dahl, the original developer of Node.js. During his 2018 talk “10 Things I Regret About Node.js,” Ryan listed some of the problems with NodeJS (such as security, package.json, and node_modules) and his vision to solve those problems with Deno.

So just like Node.js, Deno is a JavaScript runtime environment that uses JavaScript’s V8 engine, with the difference being that Deno adds native support for TypeScript and is built in Rust.

Features of Deno

The team behind Deno lists the following feature highlights:

  • It’s web compatible, meaning it can use many web concepts—for example, ES modules—when possible.

  • It’s secure by default. All sensitive system access is blocked by default and needs to be explicitly enabled, minimizing the risk of security threats.

  • It supports TypeScript out of the box.

  • It ships a single executable (Deno).

  • It has multiple built-in utilities like a linter and a code formatter (deno fmt).

  • It contains a variety of trusted standard libraries.

To summarize, Deno promises a secure, robust, and effective runtime envi ronment to build modern, scalable applications. But that’s also what many other solutions, like Node.js, promise. So, how does Deno compare with the rest?

History of Deno and Node.js

Before Deno was announced, Node.js was easily the first option for server-side development in Javascript (or TypeScript). However, with the announcement of Deno, many people started considering it as an alternative to Node.js, mainly because it promised better speed and out-of-the-box support for TypeScript. Is it worth making the switch?

Deno was first released in May of 2018, so it’s reasonable to say that it’s still in early stages of development. It might not be fair to compare it with something that has an established ecosystem, like Node.js. Instead, let’s compare the core features of the two in the table below.

These are the key differences in core features between the two environments. For the rest of the features, things tend to be more or less the same. It’s also worth noting that the Deno team uses these differences as their selling points.