The evolution of web development has always sought a balance between performance, maintainability, and simplicity. In this process, technologies like AJAX have played a key role in creating asynchronous and responsive interfaces. However, in recent years a new proposal has emerged: HTMX, which promises to simplify the way modern web is built, drastically reducing the need for JavaScript.
In this article we analyze how AJAX works, introduce HTMX, and focus specifically on two strategic aspects: when it’s worth using HTMX and what its real limitations are.
How AJAX works
AJAX (Asynchronous JavaScript and XML) is a technique that allows the browser to communicate asynchronously with the server without reloading the entire page. This enables dynamic content updates and a better user experience.
For example, if a user clicks a button to view the comments of an article, AJAX can send a request to the server, receive data in JSON format, and display it on the screen without reloading the whole site.
Simple AJAX example
fetch('/api/comments')
.then(res => res.json())
.then(data => {
const container = document.getElementById('comments');
container.innerHTML = '';
data.forEach(c => {
const el = document.createElement('p');
el.textContent = c.text;
container.appendChild(el);
});
});
This approach works well but presents some drawbacks: you need to write JavaScript code, manage the DOM explicitly, separate data from its presentation (HTML), and often build complex APIs just to handle small UI portions.
Introduction to HTMX
HTMX is an extremely lightweight JavaScript library (about 14 KB) that extends the HTML language to perform asynchronous HTTP requests, WebSockets, and more, using simple attributes like hx-get, hx-post, hx-target.
In practice, it allows you to build dynamic components by writing pure HTML. There’s no need to use JavaScript to manage interaction.
Equivalent example with HTMX
<button hx-get="/api/comments" hx-target="#comments">Load comments</button>
<div id="comments"></div>
In this case, when the button is clicked, HTMX sends a GET request to the server, retrieves a (partial) HTML response, and inserts it into the div with ID comments. No JSON parsing, no fetch, no DOM manipulation.
When to use HTMX
HTMX is particularly useful in all those projects where a complex Single Page Application is not required but a certain degree of frontend interactivity and responsiveness is still desired.
It’s the right choice when:
- Your backend is already able to return HTML fragments (as happens in PHP, Laravel, Django, Flask, Rails projects, etc.).
- You want to reduce JavaScript overhead and keep the code simple and accessible even to teams not specialized in frontend.
- You are working on projects where interactions are limited to features like content replacement, section loading, server-side form validation.
- You need a dynamic app but do not want or cannot adopt a full JS framework (React, Vue, Angular).
- Your goal is to deliver an app that is easy to maintain, readable and understandable even for backend-focused developers.
HTMX is ideal for internal dashboards, custom modules, filterable tables, AJAX-based navigation, multi-step forms, and in general for any scenario where the presentation logic can be handled server-side.
The main advantage is that HTML becomes again the core language of the interface, avoiding the overuse of JavaScript for simple tasks. This approach also facilitates progressive adoption in existing projects.
The limitations of HTMX
Despite its power and simplicity, HTMX is not the perfect solution for every project. It’s essential to understand its limitations to avoid misunderstandings and ineffective implementations.
Not designed for complex SPAs
HTMX is not suitable for contexts where the frontend requires advanced routing, shared state management, navigation between complex views, or client-side rendering. In those cases, frameworks like React, Vue, or Svelte are more appropriate tools.
Limited client-side state management
HTMX doesn’t offer a structured system for managing state on the client. Every interaction triggers a server request. This is an advantage in many cases (logic is centralized), but it can become an issue when you want to retain temporary client-side state or avoid repeated requests.
Less structured debugging
HTMX doesn’t have a dedicated DevTools panel and lacks advanced debugging tools found in modern frontend frameworks. Request monitoring relies mainly on the browser’s network tools.
Community in development
Although the HTMX community is growing, compared to major JS frameworks, the number of plugins, components, and ready-made resources is still limited. This can slow down development in complex or highly customized projects.
Not suitable for fully headless projects
If you’re building a completely decoupled app where the frontend consumes only JSON APIs (REST or GraphQL), HTMX loses much of its value. It is meant for contexts where the server generates and manages the HTML presentation directly.
Ultimately, HTMX and AJAX represent two different approaches to building dynamic interfaces. AJAX made asynchronous, modular web interfaces possible but requires adopting JavaScript tools and architecture.
HTMX, by contrast, simplifies and “humanizes” the developer’s work, putting HTML back at the center of user-server interaction. It’s an excellent choice for lightweight projects, CMSs like WordPress, traditional backends, and situations where code clarity and maintainability are more important than extreme frontend flexibility.
We recently used it to build a custom WordPress integration for one of our Clients, with more than satisfactory results.
It’s not a universal technology, but it’s a concrete, elegant, and modern solution for far more situations than one might think.