A modern platform, arriving after the market moved

What the rebuild actually delivered

The jump from Joomla 3.x to 4.0 was not an incremental release. It required a complete dependency audit, a Bootstrap 5 interface for the administrator panel, a reworked Model-View-Controller architecture, and the adoption of namespaced PHP classes aligned with the PHP-FIG PSR standards ↗ that the broader ecosystem had been moving toward for years. The Web Services API arrived as a first-class citizen, exposing content endpoints that 3.x had never offered natively. Accessibility across the back-end was documented and improved — the kind of work that rarely makes a headline but accumulates credibility with institutional users.

The long development cycle was visible. Joomla 4 had been in public alpha and beta long enough that extension authors had time, repeatedly, to assess what rewriting would cost them. Some did; many waited. The extensions directory carried a category filter for "Joomla 4 compatible" for long enough that its presence as a filter said something on its own: compatibility was not assumed, it was earned. The compatibility question had been a recurring stress point across the project's release history, as the pattern of breaking migrations between 1.5, 2.5 and 3.x had already trained a portion of the user base to distrust major version numbers.

Joomla 5.0 followed in October 2023, dropping support for PHP 7 and tightening the framework further. The 4.x series received long-term support status, which gave agencies running client installations a documented horizon without forcing an immediate jump. The decision to maintain both simultaneously was a governance choice about who the project was serving — integrators carrying inherited installations as much as developers beginning new builds.

The market it arrived into

By August 2021, W3Techs ↗ was recording WordPress at well above 40 percent of all CMS-powered sites tracked in its methodology, while Joomla sat in the low single figures and had been declining by share for several years. Those numbers carry methodological caveats — W3Techs samples detectable installations, not active maintained ones, and the population of dormant Joomla sites inflates the count without contributing to the ecosystem — but the directional story was not in dispute.

The conditions that had driven Joomla's early adoption were largely gone. The one-click installer era had democratised deployment across all the major platforms simultaneously. WordPress had moved decisively into the enterprise with Gutenberg and the full-site editing roadmap. Drupal, under Dries Buytaert's continued direction, had consolidated its position with larger institutional clients. The space Joomla had historically occupied — more structured than WordPress, less demanding than Drupal — was genuinely contested, and the contestants had not been standing still during the years Joomla 4 spent in development.

None of that made the 4.0 release irrelevant. A project with Joomla's installed base — hundreds of thousands of sites, active extension developers, a functioning commercial template market — does not evaporate because its market-share trend is unfavourable. What it means is that a technical modernisation, however genuine, does not automatically translate into adoption growth. The platform became more defensible for the users it already had. Whether it became more attractive to users making a choice in 2021 or 2024 is a different question, and the honest answer is that the evidence is mixed.

Joomla 4 had been in public alpha and beta long enough that extension authors had time, repeatedly, to assess what rewriting would cost them.

What the governance record shows

The release of Joomla 4.0 also demonstrated something about how Open Source Matters and the volunteer leadership had chosen to spend political capital. They committed to a breaking change — extension incompatibility, interface overhaul, minimum PHP version requirements — rather than an indefinite series of 3.x patches that would have kept the codebase running without renewing it. That is a coherent governance decision, and it is the kind of decision that is easy to second-guess and hard to make. Andrew Eddie, whose name is on the project's earliest public announcements, had long argued that technical credibility required exactly this kind of periodic reckoning; the 4.0 cycle was the largest instance of that argument being acted on.

The result is a platform that is technically honest — dependency-managed, API-equipped, documented — carrying a history that begins with a walkout in 2005 and has been governing itself in public ever since.