Context
Publicly documented migrations from Adobe Experience Manager (AEM) to Drupal are surprisingly rare. Most vendor case studies run the other direction — for example, a documented transition of a global investment company from Drupal to AEM to improve operational efficiency and user experience. The clearest public reference for the AEM-to-Drupal path is a migration tooling demonstration in which content is exported from AEM and analyzed before being loaded into Drupal, using an analysis layer to inspect the exported content and make decisions for the final migration.
Because the public record here is thin, this study stays deliberately general. We treat the sources as reference material and draw transferable lessons rather than inventing specifics. The recurring driver behind a move like this is a shift away from a licensed, tightly coupled enterprise suite toward an open-source platform where the content model, taxonomy, and templating are owned in-house. AEM bundles authoring, templating, and a digital asset manager (DAM); Drupal expects you to reconstruct those concerns explicitly. That reconstruction is where the work — and the risk — lives.
What broke
The failures documented or strongly implied across the sources cluster around four areas.
Content-model mismatch
AEM organizes content as pages built from components with dialogs, backed by templates. Drupal organizes content as entities: content types, fields, paragraphs, and taxonomy. There is no one-to-one mapping. Even the reverse-direction guidance makes the pattern explicit — you must create templates that match the source system's content types and then develop the components and dialogs to hold the data. Going AEM-to-Drupal, the same problem inverts: every AEM component and its dialog fields have to be re-expressed as Drupal fields or paragraph types. Where a component packed several editable regions into one dialog, that structure fragments on the way into Drupal, and authors lose the layout guarantees they relied on.
DAM and asset references
This is the sharpest documented break. There is no out-of-the-box, plug-and-play integration between AEM Assets and Drupal. If assets remain in AEM's DAM, a custom solution must be built to pull them into Drupal — for instance, using REST APIs against the DAM. That means every image, document, and rendition reference embedded in migrated content is a potential broken link until the asset strategy is resolved: either fully migrate binaries into Drupal's file/media system, or maintain a live integration to AEM. Both paths require deliberate engineering; neither happens for free.
Internal links and references
Migration guidance stresses the need to adjust internal links and references within content so they resolve in the target system. AEM's path structure (content trees, JCR paths) does not match Drupal's URL aliases and node routing. Left unremapped, body-copy links, cross-references, and navigation entries point at paths that no longer exist. This is where redirects and SEO signals quietly erode: old URLs disappear, inbound equity is stranded, and internal linking that search and answer engines use to understand site structure breaks.
Taxonomy gaps
AEM tagging and Drupal taxonomy vocabularies are different mechanisms. When content is exported and inspected before load, the decisions about how tags map to vocabularies — and what to do with terms that have no clean equivalent — have to be made explicitly. Skip that analysis and you arrive in Drupal with flattened or lost categorization, which degrades faceted navigation and topical clustering.
What worked
The documented practice that consistently helps is analyzing exported content before the final migration. The tooling demonstration for AEM-to-Drupal centers on exactly this: export from AEM, inspect the content with an analysis layer, and use those findings to make migration decisions. Front-loading analysis surfaces the content-model, link, and taxonomy problems while they are still cheap to fix.
The second thing that works is treating templates and components as a deliberate mapping exercise rather than a lift-and-shift. Defining the Drupal content types and paragraph types up front — driven by what the AEM components actually contained — gives the import a clean target. And where assets must stay in AEM's DAM, accepting that a custom API-based integration is required (rather than hoping for an OOTB connector) sets realistic scope from the start.
Lessons
- Map the content model before you move a byte. AEM components and dialogs do not map one-to-one to Drupal fields and paragraphs. Design the target model deliberately.
- Decide the DAM strategy early. There is no plug-and-play AEM Assets–to–Drupal bridge. Choose between full binary migration or a custom REST-API integration, and budget for it.
- Treat internal links as a first-class migration artifact. Paths differ between JCR and Drupal routing; every reference must be remapped or it breaks.
- Protect URLs and SEO/AEO signals. Inventory old URLs and plan redirects so inbound equity and internal-link structure survive the cutover.
- Analyze exported content first. Inspecting content before load is the single most repeatable win in the documented process.
- Reconcile taxonomy explicitly. Map AEM tags to Drupal vocabularies and decide what happens to orphan terms.
Before you make this move
A short pre-flight checklist grounded in what the sources support:
- Have you exported and analyzed the current AEM content, so migration decisions are evidence-based rather than assumed?
- Have you mapped each AEM component and dialog to a specific Drupal content type, field, or paragraph type?
- Have you chosen an asset strategy — migrate binaries into Drupal media, or build a custom API integration to AEM's DAM?
- Have you inventoried internal links and JCR paths, and defined how each resolves in Drupal?
- Have you built a redirect map so existing URLs and search/answer-engine signals are preserved?
- Have you reconciled AEM tags against Drupal taxonomy vocabularies, including orphan terms?
This is precisely the kind of pre-migration inventory work Replatform Radar exists to make visible: content models, link graphs, and asset dependencies surfaced before the cutover, not discovered during it. The documented record on AEM-to-Drupal is thin, but the transferable lesson is consistent — analyze first, map deliberately, and never assume the platforms speak the same language.