Download websites that use Backbone.js

About Backbone.js

Front end libraries are useful in a dataset because they date the code that carries them. Backbone.js arrived in 2010 under the MIT licence, in the short period when the browser had stopped being a document viewer but had not yet settled on a dominant application framework. A site that still ships it was, with few exceptions, built while that question was open.

As of September 2026 the fingerprint appears on 207,405 sites, which is a large number for a library that new projects rarely reach for. The explanation is not that anyone is adopting it now. The code is durable in a specific way, a small JavaScript file with no build step, dropped into a template, doing one job well enough that nothing ever forces its removal. Admin panels, dashboards, ticketing screens and internal tools built on it keep working, and rewriting a screen that works is rarely justifiable to whoever signs off the budget.

For a researcher the implication is about the organisation, not the library. A public site carrying a front end stack from that era is telling you something about the release cadence behind it, the age of the surrounding application, and often the size of the team maintaining it. Enterprise software with a long support tail looks like this from the outside. So do agency built sites that were delivered, paid for and never revisited.

Distribution reflects where that generation of application work happened. The country column puts United States at 89,362 sites and the suffix column is concentrated in .com, a pattern more consistent with commercial and corporate deployment than with hobby projects.

Two limits are worth being plain about. Detection reads what a page loads, so a copy bundled into a larger build and renamed is easy to miss, and the count should be treated as a floor rather than a census. Version information is not available for this fingerprint either, so the extract cannot tell you which release a given site pinned.

What the extract does give you is the population itself, every detected domain with country, suffix and the rest of the stack on the same row. Front end modernisation vendors, component library sellers, security teams hunting unmaintained dependencies and researchers tracking how frameworks decay all need the set rather than a single answer. Checking one domain confirms a suspicion you already had. The list is what tells you how many suspicions are worth having in the first place.