A Practical Guide to Your Drupal 11 Migration

Migrating to a new major version of Drupal is a rite of passage for every organization that relies on this robust CMS.

Drupal 11 migration means far more than clicking an upgrade button. This migration secures your website’s future, performance, and user experience while making the most of new features and better stability.

You might feel overwhelmed by the idea, but with smart preparation and expert guidance, your migration journey can be both manageable and rewarding.

OPTASY, a certified Drupal migration partner, offers a blend of technical expertise and best practices for seamless migrations. This guide covers OPTASY’s methods and gives you a step-by-step plan for your own migration.
 

OPTASY’s Approach to Drupal 11 Migration

OPTASY doesn’t treat migration as a cookie-cutter process.

Every project begins with a deep analysis: their team works to understand the particularities of your infrastructure, custom code, and organizational needs.

Right from the discovery phase, OPTASY involves key stakeholders, identifies business-critical modules, and pinpoints unique site integrations (such as SSO authentication or third-party APIs).

Tools and transparency form the backbone of our approach. OPTASY leverages automated auditing with Upgrade Status and Composer checks, then pairs this with hands-on code reviews for custom plugins and themes. Site backups are mandatory, and restoration procedures are always validated before work begins.

Instead of risking tangled in-place Composer upgrades, OPTASY prefers to build migrations on a fresh Drupal 11 codebase. This method reduces technical debt, gives your site a clean slate, and dramatically improves troubleshooting and future maintainability.

Communication remains continuous. Clients receive Kanban-tracked progress, module-compatibility reports, and clear patch documentation. Testing, both automated and manual, is carried out in close coordination with clients, ensuring every nook and cranny of the site is inspected post-migration.

This partnership-based, transparent approach means your migration will be technical, successful, understood, and future-proofed.

Tyndale University faced the complex challenge of migrating their highly intricate website with 57 active content types and 100+ view displays from Drupal 9 to Drupal 10/11, while ensuring seamless functionality and managing tight time constraints across multiple stakeholders.

OPTASY executed a strategic two-phase migration approach, upgrading the core website to Drupal 10/11, updating all contributed modules for compatibility, implementing a sophisticated server-side redirection system between the new site and legacy site, and conducting rigorous quality assurance testing throughout the process.

Tyndale University achieved a modernized digital infrastructure with improved performance and security, faster load times, seamless user experience across both site versions, more efficient content management capabilities, and established a long-term partnership with OPTASY for ongoing support, all delivered ahead of schedule.

Read the whole case study here.

If you're planning a Drupal 11 migration, OPTASY's on-demand webinar provides expert insights into their proven methodology that prioritizes deep analysis and stakeholder collaboration from the start.

This comprehensive session walks you through their tool-driven, transparent approach to understanding your infrastructure complexities, custom code requirements, and critical business integrations.

Watch the webinar here.

 A Step-by-Step Drupal 11 Migration Guide

Drupal is a complex CMS and migrating your website not only looks, but also is challenging.

We like to simplify things for our clients, so we put together a quick guide with eight steps for a successful Drupal migration.

Let’s start with the first one.

1. Assess Your Context and Hosting

It all starts by mapping out your environment.

Are you self-hosted, cloud-deployed, or using a managed platform such as Pantheon?

If Pantheon’s your home, take advantage of their custom upstreams and dashboard tools for safekeeping and managing code.

Next, list all your integrations and hosting quirks, nothing is too minor. You want to know exactly what you’re working with before you change anything.

2. Prepare the Ground

First principle: Backups. Never underestimate them. Create complete exports of your code, files, and database. Try a test restore. Proving you can recover your site will give you peace of mind and a fallback plan if anything goes sideways.

Next, perform an audit of your existing Drupal site. Use Drush (drush pml) to document all active modules and themes. Track any custom modules or integrations; highlight anything unusual (think custom APIs or auth mechanisms).

3. Check Your Upgrade Readiness

Time to install the Upgrade Status module. This tool will flag blockers, incompatible modules, outdated PHP, or unsupported database versions. Get clear on these:
Are all contributed modules and themes compatible with Drupal 11?
Any deprecated code in your custom modules?
Is your server running the recommended PHP and database versions?

Then, sort your modules into three buckets:

“Ready for D11”
“Need patching”
“To drop or replace”

4. Build a Clean Codebase (Sidestep the Composer Maelstrom)

Forget trying to upgrade in place because it’s messy.

Start by generating a fresh Drupal 11 codebase, either by using a clean copy or a platform-provided starter template.

Strip out everything unnecessary from your old codebase, keeping only your .git and configuration files (such as .gitignore or .gitattributes).

Then, cherry-pick the essential config, composer, and module directories from the new Drupal 11 repo into your project structure.

When you’re set, run composer upgrade from the root of your clean new base. Composer should breeze through dependency updates now, no more mismatched requirements.

5. Re-Integrate Custom Code, Contrib, and Modules

Slow and steady wins this race. Start re-adding contributed modules via Composer, always selecting the Drupal 11 compatible versions.

For modules not yet ready, check their project pages or issue queues. You might find a patch or instructions for manual compatibility.

If a module isn’t being maintained, consider patching right in Composer or, for true stragglers, update their .info.yml with a core_version_requirement: ^11 and move them into a custom directory.

For custom code, review for deprecated APIs or functions. Update and test piece by piece, being relentless in documenting every patch and tweak.

6. Test Ferociously

Run update.php and let Drupal update its database for the latest modules and code. Don’t stop there.

Rigorously test both frontend and backend, examining content, workflows, permissions, and user admin screens. Comb through logs for errors or deprecation warnings. If you run into JavaScript issues, consider temporary workarounds like the jquery_deprecated_functions module.

Fix anything that breaks. Iterate until your site feels solid and familiar.

7. Deploy, Gather Feedback, and Go Live

Push your upgraded site to a staging environment. Invite stakeholders and power users for a smoke test; capture and triage feedback promptly. Resolve any issues uncovered in UAT (User Acceptance Testing) rounds. When the site is confidently stable, deploy to production.

After launch, keep logs under close watch, sometimes issues only show up under real-world traffic.

8. Keep Improving

A migration process isn’t an end state.

Stay up-to-date with Drupal core and module updates. Use a Kanban board or issue tracker to organize remaining tasks. Document every patch and bespoke fix directly in your codebase for future reference.

If you're planning a Drupal 11 migration, OPTASY's comprehensive checklist offers a strategic approach that goes beyond cookie-cutter processes to deliver tailored solutions for your organization.

This detailed guide covers everything from initial infrastructure analysis and stakeholder involvement to identifying business-critical modules and handling unique site integrations like SSO authentication and third-party APIs.

Download the checklist here. 

Lessons and Insights

Every Drupal 11 migration looks a little different.

A clear trend: clean base installs with side-by-side re-integration yield smoother, maintainable upgrade paths compared to risky in-place upgrades. Continuous backups, regular restores, and rock-solid documentation transform painful surprises into minor bumps.

With OPTASY’s approach and this practical guide, your migration can become an opportunity, one not just to modernize but to reimagine and future-proof your digital presence.

Embrace the process, keep communication open, and you’ll find Drupal 11 migration is less a trial and more a smart investment in your site’s next chapter.

For more information and a clear, simple Drupal 11 migration path, contact OPTASY.