Why teams leave AEM
Adobe Experience Manager is rarely abandoned because it cannot do the job. It is abandoned because of what doing the job costs. Licensing scales with traffic and author seats in a way that stops making sense once a marketing site's growth outpaces its content complexity, the authoring experience trains editors into workarounds that live in nobody's documentation, and every front-end change runs through a Java build and deployment pipeline that a small team of web engineers did not sign up for. The trigger is usually a specific moment, a licence renewal that lands on someone's desk with a number attached, a hiring search for an AEM developer that drags on for months because the skill is scarce and expensive, or a simple marketing page that took six weeks to ship because of how many systems it touched on the way to production.
None of that means the migration is simple. AEM projects accumulate years of components, workflows, and content structure that nobody fully remembers building, and the actual risk in a migration is rarely the new stack. It is everything hiding inside the old one.
The phased traffic-cut, not a big bang
The instinct to build the new site, test it thoroughly, and cut over on a Friday night is understandable and almost always wrong for a site with real traffic and real revenue behind it. We run migrations as a phased, reversible traffic cut instead, using the CDN or edge layer as the routing point rather than a DNS switch.
- Section by section, not all at once Route the lowest-risk section of the site, often a blog or resource centre, to the new stack first, at the edge, while everything else still serves from AEM. Prove the new stack under real traffic before anything that touches revenue depends on it.
- Percentage-based cutover per section Once a section is live on the new stack, split traffic 5, then 25, then 100 percent, watching error rates, Core Web Vitals, and conversion metrics at each step, with an automatic rollback trigger if any of them regress past an agreed threshold.
- Content freeze windows, scoped narrowly Freeze authoring only on the section actively being cut over, for the shortest window that keeps the content-mapping script accurate, rather than freezing the entire site for the length of the project.
This is slower than a single cutover weekend, typically eight to fourteen weeks for a mid-size marketing site depending on component count, but it converts a single high-stakes event into a series of small, individually reversible ones, which is the entire point.
Getting the migration sequence right
The order of operations matters more than almost any technical decision in the project, and the sequence that fails least often looks like this.
- Content model mapping first Before any code, map every AEM component and content fragment type to its equivalent in the new content model. This is a spreadsheet exercise, not an engineering one, and skipping it is the single most common cause of scope blowing up mid-project.
- Template and component audit Inventory every template and component actually in use, not every one that was ever built. AEM installations accumulate components nobody has used in three years, and migrating them is wasted effort that a usage audit against real page data avoids.
- Editorial retraining in parallel, not after Start training content editors on the new authoring interface as soon as the first section is stable, running both systems side by side, so the organisational change happens gradually instead of landing all at once on cutover day.
- Engineering build last Only once the model is mapped and the component inventory is final does the composable front end get built against it, which sounds obvious and is nonetheless the step most teams reverse under deadline pressure.
Content-mapping pitfalls that blow up timelines
A handful of specific AEM patterns account for most of the schedule risk we see, and they are worth naming directly.
- Rich text component sprawl Years of editors pasting formatted content into a generic rich text component means a meaningful share of "structured" content is actually unstructured HTML with inline styles. Plan an explicit content cleanup pass, not an automated one, since automated rich-text parsing reliably breaks on the inconsistencies that accumulate over years of manual editing.
- DAM asset references Assets referenced by internal AEM path rather than a stable public URL need a rewritten reference for every single usage, and a broken image on a high-traffic page is the fastest way to lose executive confidence in the migration mid-project.
- Multi-site management and content inheritance Sites using MSM to roll shared content down to regional or brand variants need that inheritance hierarchy explicitly rebuilt in the new model, since most headless CMSs have no native equivalent and this needs a deliberate design decision, not an afterthought.
- Experience fragments and personalization rules Personalisation logic embedded in AEM's Target integration or in experience fragments is often undocumented anywhere except the live configuration. Extract and document every active rule before touching the pages that depend on it.
- Workflows and launches Approval workflows and scheduled launches represent editorial process, not just content, and the new stack needs an equivalent before editors will trust it enough to actually adopt it.
Choosing the composable stack
The replacement is almost always some combination of a headless or hybrid-headless CMS, a modern meta-framework for rendering, and an edge layer for routing and caching. The specific choice matters less than the discipline of choosing it for the content model you actually mapped, rather than for the framework a team is excited about. We generally look for a CMS with a genuinely flexible content model, first-class localisation support if the site is multi-region, and a preview mode that editors can trust, since editorial trust in the new authoring flow is what actually determines whether the migration is considered a success six months later, not the engineering metrics.
The rollback plan you write before you start
Every phase of the cutover needs a rollback path defined before that phase begins, not improvised if something goes wrong.
- Edge-level routing reversibility Because traffic is routed at the CDN or edge layer rather than DNS, rolling a section back to AEM is a configuration change measured in minutes, not a DNS propagation measured in hours.
- Content freeze reversal Document exactly how a frozen section resumes normal AEM authoring if a rollback happens mid-migration, including what happens to any content edited in the new system during the freeze.
- Defined rollback triggers Agree the specific metrics and thresholds that trigger an automatic rollback before cutover starts, error rate, Core Web Vitals, and conversion rate are the three we watch most closely, so the decision is not made emotionally in the middle of an incident.
A migration off AEM is rarely lost on the new stack's technical merits. It is lost on unmapped content, untrained editors, and a cutover plan with no way back. Solve those three and the rest is ordinary engineering. This is the kind of migration our software and web development team runs end to end, from content mapping through cutover.
Keep reading