The .NET Framework that many older CMS platforms still run on wasn't built for the request volumes modern ticketing sites see. Microsoft's own migration guidance confirms the shift to modern .NET brings meaningful performance and scalability gains, along with cross-platform flexibility the old framework never had. None of that is CMS-specific. It's a change to what's running underneath the CMS, not the CMS itself.
That distinction showed up clearly in two organizations that made this shift. One paired the framework change with a full CMS migration to Umbraco: its checkout page load time dropped from 13.9 seconds to 4.76, and a seat-selection page went from nearly 24 seconds to just over half a second. A second organization, one of the largest performing arts institutions in the country, kept its existing CMS and changed only the framework. Its average page load time still dropped by more than half.
Site speed conversion rate describes the relationship between how fast a page loads and whether a visitor completes a purchase. Rather than rely on industry averages, this piece looks at that relationship through what three organizations actually measured on checkout, seat selection, and the product detail page, the steps closest to an actual transaction.
A common assumption is that switching content management systems will fix a slow website. The evidence from these migrations suggests otherwise: the framework underneath, not the CMS, was what changed the outcome.
A CMS migration alone doesn't automatically make a website fast. Moving old code to a new CMS will most likely have the same performance issues. Architecture, implementation, and platform all matter.
Monika Worwa
Back-End Developer, Adage
Adrienne Arsht Center for the Performing Arts' migration changed both the CMS and the underlying framework at once, moving toUmbraco and .NET Core together. A second organization we've worked with, one of the largest performing arts institutions in the country, made a narrower change: the same CMS, just the shift from an older .NET Framework to .NET Core, alongside a version upgrade. Its average Lighthouse performance score rose from 61 to 87, and its average Largest Contentful Paint, the time it takes the main content of a page to render, dropped from 3.7 seconds to 1.2 seconds.
That's the cleaner test. When the only thing that changes is the framework, the gains still show up. The platform wasn't what was slowing things down.
Arsht Center didn't upgrade because their site was failing. They upgraded because two things converged: dissatisfaction with the cost and service of their previous CMS, and a major Tessitura version shift (from v15 to v16).
Tackling both changes together, rather than patching one and deferring the other, was the more efficient path. It also gave the team a chance to rethink the patron's digital experience as a whole, not just swap one system for another.
The results, measured before and after the migration:
As Worwa explains, "the biggest improvement was taking the opportunity to modernize the entire website, making it faster today and easier to grow in the future".
The site modernization included moving to .NET Core, refactoring parts of the codebase, improving caching, and adopting an updated version of Adage's ACE Commerce product with additional components and performance improvements built in. The reorganized codebase also makes new features faster to deliver and the site easier to maintain going forward, on top of the immediate performance gains.
SFJAZZ's site rebuild moved the organization to Umbraco 13 and .NET Core, alongside updated versions of ACE Commerce and SmartSeat built for Tessitura v16. The previous setup ran on an aging codebase and an outdated version of the ticketing platform, the kind of accumulated technical debt that makes a site harder to maintain even before speed becomes a factor.
The rebuild also included a design refresh and new features, addressing a content management system that had grown bloated over years of updates.
It's critical we help organizations understand the need to continually iterate on their website, and the importance of keeping your tech stack up to date as the digital landscape evolves.
Amy Catanzaro
Manager of Project Delivery, Adage
SFJAZZ and Adage have worked together for years, a partnership Amy describes as one which the client consistently looks ahead to improve its digital presence, rather than reacting to problems as they surface.
Arsht Center modernized before their site showed obvious problems to patrons, driven by a converging opportunity rather than a breaking point. That timing question, whether to wait for something to break or act on one, is worth asking directly.
A few questions worth asking before any upgrade decision:
A team that treats this as a full performance audit, not just a platform swap, will ask these questions before starting. Ongoing support after launch matters too. Once a modernization ships, keeping it optimized takes continued attention, not a one-time fix.
The organizations in this piece didn't pick a platform and hope for speed. They treated performance as an outcome of how the whole system was built, not a feature of any one tool.
Slower load times, especially on checkout and seat-selection pages, can increase the chance a patron abandons a purchase. These pages carry the most weight because a delay here risks a completed sale, not just a page view.
No. A CMS migration on its own doesn't guarantee better performance. Speed improvements come from the underlying framework, the code architecture, and how the migration itself is executed, not from the platform choice alone.
Common causes include an outdated framework, years of incremental customizations that were never cleaned up, and workarounds built to compensate for performance problems rather than fixing them. A site can run on a modern CMS and still be slow if these issues weren't addressed during migration.
Google's Core Web Vitals standard sets “good” Largest Contentful Paint at 2.5 seconds or less. For pages closest to the transaction, checkout and seat selection, that's the bar to aim for. Every additional second beyond it raises the risk of an abandoned purchase.
Look past the platform name and ask about the underlying framework, how caching and architecture are handled, and whether the team treats the project as a full modernization rather than a like-for-like swap. That distinction shapes the actual outcome more than the CMS itself.
Sources
Technical claims about performance and scalability gains from moving off .NET Framework draw on Microsoft's own current migration guidance: Migrate from ASP.NET Framework to ASP.NET Core, Microsoft Learn.
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Lead Back-end Developer at Adage Technologies, specializing in Tessitura integrations and web development. Monika brings deep experience with Umbraco, .NET Core, and .NET Framework to complex digital projects, helping clients build and modernize websites and integrations across the Tessitura ecosystem.
Manager of Project Delivery at Adage Technologies. Amy spent over 20 years as Director of Sales at the Cincinnati Symphony before shifting to digital delivery, and now draws on her Tessitura expertise to lead advanced projects across the performing arts sector, including SFJAZZ's recent site rebuild.
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