The balance between code readability and code optimization must always be maintained. You should never compromise the performance of an application while it is being developed. Rushing through this process for a fast time to market makes the situation even more difficult. Performance is a critical factor in the success (or failure) of any web application. Frequent crashes and long wait times annoy your website visitors. Let’s see Javascript.

Use these tips to see dramatic improvements in your application’s performance. Let’s start with them.

Training Based on Long-Term Projects

Sometimes javascript development company is terrified of colliding with their existing codebase. They call code that they haven’t written in the near future obsolete. However, the opposite is true. Maintaining one code in a project for several years can provide more knowledge about software development than a few short-lived, sharp-firing, but just as quickly fading projects.

Decisions Made Many Years Ago Still Affect the Entire System

The decisions made today determine the long-term fate of the system. The main question is: what changes can be made now? What needs to be improved? Every developer sometimes has a desire to destroy everything and start from scratch. But in most cases, it is very difficult to find problems with existing code: it seems that the writing logic is worth keeping, but a different structure is needed. Here are the main issues with JavaScript code structure.

Tricks for Javascript Developers

Avoid Complex Structures

“Difficult” doesn’t mean big. Every non-trivial project contains a lot of logic. There are many cases requiring consideration and verification. Lots of different data to be processed. Difficulties arise from the intertwining of various problems. This cannot be avoided altogether, but when these problems are taken apart separately, the result is that they can be brought together in a certain controlled way. Let’s look at simple and complex data structures in JavaScript.


The simplest reusable piece of JavaScript code is a function. In particular, a pure function is one that receives information and produces a result (return value). The function receives all the required data directly as parameters. The input data or data context does not change. Such a function is easy to write, easy to test, easy to fix, and easy to use.

High-level design patterns are not required to write good JavaScript code. First, you need to be able to use the simplest technique in a reasonable and appropriate way: the program should be structured using functions that correctly perform one specific action. Then the low-level functions need to be matched against the high-level ones.

Functions in JavaScript are fully qualified values, also called first-class objects. As a multi-paradigm programming language, JavaScript allows for powerful functional programming patterns. Even a basic understanding of the basics already helps you write simpler programs.


The object is another complex structure. The simplest object maps strings to arbitrary values without logic. However, it can also contain logic: Functions become methods when attached to an object.

Objects in JavaScript are fairly common and versatile. The object can be used as a parameter package with multiple function handlers. In addition to grouping related values, an object can structure a program. For example, you can put several similar functions on the same object and let them work with the same data.


The most complex structure in JavaScript is the class. It provides the basis for objects and, at the same time, produces these very objects. It is a mixture of prototype inheritance and object creation. Furthermore, it interweaves logic (functions) with data (instance properties). Sometimes a constructor function contains properties called “static” properties. Templates such as “singleton” overload the class with even more logic.

Classes are acceptable if they have one specific purpose. In my experience, adding a lot of questions to the class should be avoided. For example, components in React that contain an internal state are usually declared as classes. It only makes sense for a specific problem area. They have one specific purpose: The grouping of props and state data and a couple of functions that work with these data types. At the center of the class is the render function.

Tricks for Javascript Developers

Choice of Structures

Several recommendations from Fireart experts with many years of experience: Use the simplest, most flexible, and most versatile structure: function. It is best to use a pure function whenever possible. Avoid mixing data and logic in an object whenever possible. Avoid using classes whenever possible. When used, they must perform one specific action.

Most JavaScript frameworks have their own way of structuring code. At the core of component-based UI frameworks like React and Angular, components are usually represented by objects or classes. It’s better to prefer composition to inheritance: To split the task into multiple parts, simply create a new lightweight component class.

This does not mean that you only need to adhere to these structures to model your business logic. Better to put this logic in functions and separate them from the structure of the user interface. This allows you to modify the framework code and business logic separately.

Numerous Modules

In the past, managing dependencies between JavaScript files and external libraries was a lot of trouble. At first, CommonJS or AMD modules were used. The community later settled on standard ECMAScript 6 modules.

Modules have become an important code structure in JavaScript. Modules can simplify or complicate the structure, depending on their use.

Now it’s better to use modules in a completely different way. Before quite large files with multiple exports were created. Otherwise, one export was a huge grouping object for many constants and functions. Current goal is to create small flat modules with one or more exports. As a result, one file per function, one file per class, and so on. The foo.js file will look like this:

export default function foo (…) {…}

Or like this, in the case of specifying the export name:

export function foo (…) {…}

As a result, individual functions can be accessed and reused more easily.

Reliable Code

These guidelines relate to the overall structure of the code. The biggest impact on the reliability of JavaScript applications knows the factors that can pause a JavaScript program and being able to prevent them from occurring.

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