Before we go to a deep dive on this topic, let us understand what Deno and NodeJS are and their uses.
Nodejs is a runtime built on the Google V8 Javascript engine, and it is primarily written in Javascript.
The main aim of creating Node.Js by the creator Ryan Dahl was to ensure that the website has good push capability and operates in real-time. In addition, Nodejs ideally works with an event-driven, non-blocking I/O paradigm which makes building websites unique.
Nodejs works in unique ways. However, it is not primarily ideal for building CPU-intensive web applications. Developers have stated their advantage in creating fast and pretty scalable web applications. Nodejs operates on a single thread, non-blocking I/O calls, supporting a lot of concurrent connections.
A lot of developers have enjoyed the use of Nodejs. However, there are some pitfalls that these developers may not notice that often choke their programs. The first pitfall is sharing a single thread to all the client's requests to develop the applications. When there are many heavy computations on the system, it could eliminate the single thread, which could lead to incoming requests being blocked and crash the program.
Ideally, Developers can use Nodejs to build server-side applications. However, if you are working with a relational database, you will like to use other options. Developers cannot also use Nodejs for heavy computations because it will most like affect the event-driven, non-blocking I/O model that Nodejs provides.
Looking at Deno
Deno was officially released in May 2018, and it was created to solve the inherent problems of Node.js. Of course, it doesn't mean that Node.js is bad. However, there are a few things that the creator wished he tackled in Node.js. Some of these are the security, modules, and some of the dependencies.
The creator, Ryan Dahl, built Deno as a Typescript runtime on the V8 Javascript engine. Deno was built in Rust compared to Node that Ryan Dahl had created in C++
One unique feature of Deno is that it makes it easy to work with Typescript without configurations. Also, if you choose to work with Deno, you can write programs in Javascript and execute them with ease.
Why is Deno gaining popularity?
In recent times, because of the level of developments that are taking place on the internet, Deno is slowly gaining popularity amongst developers. However, It is not a threat to Node as Node developers can still build scalable and fast scalable with ease.
The primary function of Deno is to become a productive environment for modern-day development. Like Node, Deno provides a good event-driven architecture that uses IO utilities with the blocking versions.
Another reason why Deno is gaining a lot of popularity is because of its security features. For example, malicious scripts and actions cannot tamper with the network connections and access the main file with permission.
How is Deno different from Node?
The first difference between Deno from Node is Security. Deno is secure by default, and unless you enable the options, a program that is run with Deno has no access to the environment. However, when you intend to access secure and sensitive information, it requires that permissions should be granted by showing you a prompt.
The second difference is that it ships only as an executable. It does not use npm, and it sends with built-in tooling features to improve the overall experience. When writing APIs in Deno, all the async actions always bring out a promise. It is why APIs writing in Deno is different in code structure from APIs written in Node.
Deno Vs. Node in terms of performance
The truth is, it is challenging to compare Node vs. Deno in terms of performance due the Deno's years in existence. However, based on our review, we cannot say that the performance will remain the same as Deno grows.
However, there are a few things that we can point out. First, both Node and Deno run on the javascript V8 engine. There is no notable difference when it comes to running Javascript by itself. When comparing the performance, the only thing that is worthy of note is that Node performs better in terms of HTTP throughput, and Deno performs better when it comes to developing applications with low latency.
Most people often think that because Deno supports Typescript, there would be a performance bottleneck. The truth is that they are wrong. Typescript is built to check types only during the transpiling process, and that is why it cannot affect the runtime performance.
In a nutshell, both Node and Deno work with heavy optimization protocol to gives users the best performance in their unique way.
Will Deno replace Node?
The Deno community in recent times is multiplying, and we see rapid growth in the future. However, we do not see Deno taking over the role of NodeJS shortly. Deno is one runtime that gave us the excitement of seeing a new technology that addresses the shortcoming of Node.
But, Node is currently embedded into the Web development landscape, and it is not going anywhere anytime soon. What we should be looking forward to in the future is utilizing the strong points of these two JavaScript runtimes and building a lot of exciting projects.
Should I use Deno or Node?
The main goal of Deno is not to serve as a replacement for Node. It is meant to be an alternative. Several developers are not looking to repurpose their codebases in Node. However, if you intend to use Deno, you must understand that Deno focuses more on security and can bundle up the entire codebase in a single file. In addition, Deno makes it easier for Javascript developers to create good utility scripts written in Python or Node.
For now, if you intend on starting any lightweight project, I'd suggest you stick with Node because it is more stable. With this, any unexpected behavior that could affect the entire application could be avoided.