Stay is a small but effective library for the creation of dynamic xhr-driven web applications.


00Minified + gzip package size for @zayesh/stay in KB



Build status Windows build status GitHub version npm version Dependencies

Stay is a small but effective module for the creation of dynamic xhr-driven web applications. It expects the server to be able to send the page content as a JSON string in which the key names correspond with the IDs of the target DOM containers.


Download the minified library and include it in your project:

<script src="/js/stay.min.js"></script>

You can also install this module with npm.

$ npm install @zayesh/stay


The client part

import Stay from "@zayesh/stay";

var stay = new Stay({

    // Logs to console by default
    stderr: "myDomElement",

    // Default is "/json"
    infix: "/asyncRequests",

    // Default is 60000ms, 0 means no timeout
    timeoutPost: 0,

    // Default is 5000ms
    timeoutGet: 0,

    // Default is true
    autoUpdate: false


stay.addEventListener("navigate", function() {

    console.log("Page navigation has started.");


stay.addEventListener("receive", function(event) {

    /* If autoUpdate is disabled, the programmer has to decide 
     * when to update the page content. The update() method MUST 
     * be called at some point to unlock the system!



stay.addEventListener("load", function() {

    console.log("The requested page has been loaded.");


The server part

Every GET and POST endpoint needs to be available as a condensed JSON resource. This includes dynamically generated pages and error pages. Serving a JSON version of each resource should be seen as an additional feature and nothing more.

Stay is rather tolerant when it comes to different URI patterns, but a well-structured URI configuration is the foundation of a good web application. Take a look at some recommendations for good URI design if you haven't already! These guidelines are a good starting point.

The following example shows what's going on behind the scenes of Stay:

<a href="/foo/bar">Hyperlink</a>

This link will internally be converted to:


The modified URI won't be seen by the user and the infix can be freely chosen by you. If we assume that the original URI points to a simple HTML page which looks like this:

        <meta charset="utf-8">
        <div id="main">Bar!</div>

then the JSON equivalent must look like this:

    "meta": {
        "title": "Foo"
    "main": "Bar!"

Stay will replace the current children of #main with the received content which is a simple text node in this case, but could be any HTML content. The current page's title will also be adjusted and the browser history will be managed for you to support the back and forward browser controls. Although the above example HTML is minimal, it highlights the main aspects of asynchronous web applications:

  • More efficient bandwidth usage
  • Better loading performance
  • More control over the navigation process
  • Consolidation of a main page structure
  • Still highly customisable!

Linked Media and External Resources

Stay detects external resources and doesn't touch them. The user will experience a synchronous navigation. Hyperlinks to internal resources like images or executable files are problematic because they can't be identified as such by their URI alone. You may, however, define an arbitrary number of regular expressions to exclude specific URIs.


When linking a resource that can't be represented in JSON format, you should consider moving it on a dedicated file server. Since Stay ignores external resources by default, the file would just open as expected.




Maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code.


Copyright (c) 2015 Raoul van Rüschen
Licensed under the Apache 2.0 license.

If you find any bugs or have a feature request, please open an issue on github!

The npm package download data comes from npm's download counts api and package details come from npms.io.