The most obvious answer to the popular tech-question “If Deno can replace NodeJS?” is that… wait a minute! We’ll have to figure that out. In this write-up we’ll discuss many factors that will help us determine the answer to the ultimate question, let’s take it one by one.
For starters, let’s clarify one thing, Deno is not created by any competitor of NodeJS; both the technologies share the same pioneer, Ryan Dahl. So, does that imply that Deno automatically becomes a de facto replacement of NodeJS? Should you start planning to refactor all codes into Deno now?
Well, not so soon. You should first deeply understand what Deno is?, and how it is different from the popular technology NodeJS.
Keep reading to know more!
What is NodeJS?
NodeJS is a JavaScript run-time environment that has an open-source nature. It is applied when the code that is composed has to be executed in JavaScript.
It can run on multiple platforms, like Linux, OS X, Windows, and so on. Therefore, brands aiming to expand their audience reach have been actively using NodeJS in their tech stack.
The incredible NodeJS allows developers to compose command-line codes and will enable the back-end scripts to run, allowing them to develop dynamic pages before they go on to the user’s browser.
The JavaScript environment’s fundamentals of working are based on a motto known as “JavaScript Everywhere.” Thus, it amalgamates each of the app development tasks to substitute as a single programming language. Instead of managing multiple functions in various languages, a developer can use a single language for both the client-side and server-side.
The environment is robust to such a great extent that overlooking the advantages it provides to the app is a challenging task. However, you will have to hire NodeJS developers to bring out the best in your technology.
What is Deno?
Deno is a newly launched Typescript/JavaScript run-time backed by the V8 JavaScript engine and the Rust programming language. The Rust language offers performance close to C++ and is integrated with memory security without using garbage collection.
In simpler words, Deno and NodeJS are siblings, as Ryan Dahl created both. The developer behind the two remarkable technologies has already pointed out some cons of NodeJS, but the issues are not easily covered due to its current build-up. Therefore, a new JavaScript-based platform, capable of tackling the shortcomings of NodeJS was launched, and it is called “Deno.”
What led to the rise of Deno?
Several factors were backing the development of Deno. However, the ones contributing the most are:
- The module system backing NodeJS is poorly designed and has a centralized distribution.
- Many legacy APIs were not supported in NodeJS.
- Fewer security features in NodeJS and other programming languages.
The complete details of Ryan Dahl’s decision on developing Deno can be found on Youtube videos of his symposium.
Features of Deno:
- Deno has an integrated built-in Typescript compiler. The technology is pretty cool since it allows a developer to compose JavaScript/Typescript right away. If one chooses to use just JS in code, it will not invoke the TS compiler; neither will it bloat the run-time.
- It is secure by default. This implies that the script, by default, would be run without a file system or network access.
- Deno has decentralized packages. One major issue with NodeJS is the centralized approach it has. Suppose a developer installs a dependency through NPM in the NodeJS App. In that case, all the other dependencies for that particular package will be installed and increase the Node modules’ size.
Whereas Deno’s approach is decentralized, any third-party packages can be imported via the URL itself. Once loaded, it will be cached to the hard drive. The cache will not be updated unless a developer runs the code via the reload flag.
- Deno has a single executable file. It runs on the servers as a package manager as well as a run-time. In contrast, every dependency would be installed via a package manager such as NPM for a NodeJS program to run.
- It offers ES modules. Deno fails to support “require(),” instead, it uses ES modules for importing the support for browsers. ES modules are the latest feature integrated into the JavaScript specification.
- Deno allows a developer to utilize the await in the global scope without wrapping it up in an async function.
- It provides Tokyo to facilitate asynchronous tasks. Unlike NodeJS, Tokio doesn’t have to use callbacks and is maintained by Rust’s core team.
Let’s understand the essential features in deeply:
What’s new with Deno?
Deno is not just some newly launched JavaScript run-time that is compatible with NodeJS. Instead, Ryan has attentively integrated some features into Deno that he thought NodeJS had missed.
- Integrated Security:
Using NodeJS, a developer can access almost everything; this means they can write and read in the file system, access environment variables, make outgoing requests, and do much more. Although it’s a massive benefit for a developer to access this function, it can prove to be disastrous if not enough attention is paid while writing the code.
To counter that, Deno utilizes command line arguments to disable or enable various security features. So if you require the script to access the /etc. file, then you can push the following code:
deno –allow-read=/etc myscript.ts
It’ll permit one’s code to access and read from the folder. If anything else comes up, one will get a security exception.
This shares similarities with other platform’s security management. If you’re using Android, there might be many instances when apps would ask you to permit them to use various systems inside of your mobile devices; the exact same concept can be applied here.
If you use these flags in your command line code to execute the script, you automatically provide the permission your code requires.
- A more comprehensive standard library:
Since the first version of NodeJS, JavaScript has continuously improved its standard library, but it still has a long, long way to go compared to other languages. Deno claims to have worked on this aspect and provides a complete standard library providing developers with the benefit of using official tools to carry out basic tasks and only requiring the developer to use external libraries for complicated operations.
Essentially, Deno offers various tools to facilitate tasks like adding color to the terminal text, generate UUIDs, work with external data structure, and even code WebSockets.
Many other more basic modules are also available with Deno, including data helper functions, file system access, HTTP-related functions, etc.
- No need to maintain NPM or node_modules folders:
This point is the “table-turning” aspect of Deno. Since the very launch of NodeJS, developers have had their share of doubts- if it’s too bloated? If it’s the incorrect way of distributing dependencies?
This aspect has always been a controversial one, but Deno is here to solve it!
So how does Deno manage dependencies? So far, it simply allows a developer to require modules. In other words, you can push:
import * as log from “https://deno.land/std/log/mod.ts”;
This allows a developer to eliminate the need to have her/his own centralized repository. However, the developer needs to be extra careful while practicing this since you lose control when importing modules from a third-party source, which makes your app exposed and open.
Comparison between the two:
| Feature | NodeJS | Deno |
| Built with | C++ | Rust |
| Dependency package management | Centralized | Decentralized |
| Module System | CommonJS require() syntax | ES module import statements |
| TypeScript Support | It is possible using TypeScript compiler | Supports TypeScript out of the box |
Event Loop | Libuv | Tokio |
Will Deno Replace NodeJS?
To be honest, it is hard for Deno to replace NodeJS anytime soon. Many developers started using NodeJS back in the day when the version was around 0.10, and most of them were using it in production. It is so because, at that time, there was no technology in comparison to it. Neither PHP, Ruby, nor Python offered an asynchronous I/O model at the server-side. And with the growing time, NodeJS has managed to evolve to match all the industry standards. Is it the perfect technology? Well, not actually, but it is still pretty efficient.
Deno holds no difference; right now, it is just a cluster of ideas that have been worked upon for two years. It’s too soon to say since it is yet to be tried and tested in the production systems. It still hasn’t been appropriately reviewed or put into borderline situations or weird scenarios. Therefore, saying anything right now would be a waste of energy.
What the future holds for Deno is yet to be determined.
Parting Thoughts:
As we have stated earlier, it is still too soon to base our thoughts on Deno’s capabilities of replacing NodeJS, but one obvious thing is that Deno has many potentials to rock the future market. Although there is no perfect language, Deno promises to solve many issues NodeJS faces.
Only the first version of Deno is released. Thus there are high chances of encountering issues that will be fixed in the future.
Anyway, the entire Javascript community is excited to use Deno. You, too, can hire Full Stack developers and prepare your project to collaborate with the advanced technology, Deno.
