Drupal 7 to Drupal 8, 9 and beyond: Your last major upgrade?
Eric ToupinThu, 03/11/2021 - 11:41 Drupal

Upgrading from Drupal 7 to Drupal 8 is a major project (a full rebuild in most cases) that can rival or even top the original cost of application development. Upgrading from Drupal 8 to 9 and beyond, in comparison, requires just a tiny fraction of that effort. Here’s a look at why — and why you should take the leap from Drupal 7 to Drupal 8 and 9.

The upgrade from Drupal 7 to Drupal 8 was a major theme for plenty of our clients over the last few years. Drupal 8 — and versions beyond — boast a wide range of benefits that stem from a more modern architecture, but one of the biggest wins in my mind is the advent of semantic versioning (for Drupal) and a renewed commitment to making Drupal upgrades easy forever. Moving to Drupal 8 could be your last major upgrade.

The ghost of Drupal past

The move from Drupal 7 to Drupal 8 isn’t easy. While it’s often still touted as an “upgrade process” the reality is that it boils down to a complete rewrite of the codebase and a content migration. We’ve worked on more than a handful of Drupal 7 to Drupal 8 upgrades in the last years, and the majority constitute a “six months or more” sized project.

One reason for that is Drupal’s new Symfony reliant architecture that leans far closer to the tenets of object oriented programming (OOP) versus the more procedural approach used in previous Drupal versions — a significant technical change which in most cases means Drupal 7 code simply won’t work in Drupal 8. Add to that a completely revamped templating system and you get a similar obstacle on the front-end: Drupal 7 templates & templating systems won’t work in Drupal 8. Those major changes along with a potentially long list of complications with Drupal 8 data migrations is likely to land your Drupal 7 to Drupal 8 upgrade squarely in “rebuild the application” territory.

The good news is that it’s the last time.

Drupal 8 and beyond: Your last major upgrade

Drupal 8, 9 and beyond promise a continued investment in modern architecture, incremental major feature releases, greater stability and sustainability, and a much larger network of invested developers — among lots of other perks. Perhaps the best news to come along with the new Drupal architecture is that large-scale, overhaul-style major version upgrades will be a thing of the past. And we’re beginning to see that now as we begin moving Drupal 8 sites to Drupal 9.

Clearing the road ahead: A commitment to easy upgrade paths

With Drupal 8 comes the commitment to semantic versioning. Semantic versioning isn’t just a naming convention for software versions, it’s a descriptive norm that guides how new versions of code should be written and establishes strict backwards compatibility requirements. The upshot for end users is significant but manageable incremental changes between major versions (say 8.x and 9.x) which aim towards seamless major version upgrades. Major versions can no longer make dramatic jumps (like Drupal 8’s move to OOP or the Twig templating system) which necessitate major code rewrites, but instead make small, reasonable changes between minor versions.

With the new approach to versioning developers get a variety of automated tools that ease the shift between minor and major versions. Deprecation checking means developers get notices in their code editors when parts of the existing codebase have been marked as deprecated, i.e., queued for change or removal in an upcoming major version. Automated tools like Upgrade Status or Drupal Rector and its Drupal front-end Upgrade Rector can provide detailed upgrade status information and even automatically update code between major versions. All in all, upgrade paths are looking easier than ever.

A wider foundation: Sustainability through community (and Symfony)

Building Drupal on top of Symfony means even further specialization on the Drupal end. The new Drupal versions use Symfony for a host of standard web application tasks — things like form validation, data serialization, data storage and retrieval, content translation, templating, easy and human-readable configuration management with YAML — the list goes on. Building on top of Symfony lets Drupal developers build closer to the consumer level, i.e., build the media libraries, authoring experiences, layout managers, etc that really matter to users.

Drupal’s reliance on Symfony — a robust and mature web application framework with more than 600,000 registered developers — also translates to greater sustainability through a larger active community. Besides adding Symfony’s 600K developers to Drupal’s roughly 1 million, the move to a modern architecture and more collaborative versioning system makes Drupal more attractive to developers on the leading edge of their disciplines. That fact alone stands to benefit the Drupal community through new, top-tier talent driving further innovation.

Regular new stuff: Incremental feature releases

With Drupal’s new versioning cycle comes another benefit: major new features in minor version core releases. As Drupal 8 churns through minor releases (the second place in the three place version number, e.g. “y” in x.y.z) it continues to add brand new features to core. Unlike previous major Drupal versions, these aren’t just bug fixes and security upgrades. Game changing modules like JSON API, Media, and Layout Builder were all added to Drupal 8 in minor version releases — and more are in the works.

What does this mean for end users? A greater commitment to standardized features that meet primary needs (like media and layout management, for example) and a bigger pool of developers making sure those features are updated, stable, and compatible.


I just finished one of my first Drupal 8/9 upgrades yesterday for a small searchable database of computer science tips & tricks run by a college out of Claremont, California. Admittedly it was a pretty simple site, but the upgrade took me just two hours. Wow.

Aten will be working on a variety of Drupal 8 to Drupal 9 upgrades in the coming months, but the landscape is almost unrecognizable compared to our Drupal 7 to Drupal 8 efforts. For us, for the rest of the Drupal world, and for our clients, that is real good news.

Joel Steidl