According to a 2025 survey of over 500 US-based IT professionals, 62% of organizations still rely on legacy software systems. And 50% of those surveyed say the biggest reason they haven’t upgraded is because “the current system still works.”
But 20% of those organizations rely on legacy software specialists, and 7% outsource to external vendors—both of which add additional security risks.
The flip side of those statistics is the opportunity they represent. David Yadzi started Filtrous in his garage, selling laboratory syringe filters to other businesses. A decade later, the company had grown into a global multimillion-dollar laboratory supply company, but their outdated ecommerce platform was dragging on every part of the operation.
Since moving to Shopify, Filtrous launched their wholesale storefront in 63 days, cut 12 hours of manual work per week across their teams, and lifted organic conversion by 27%.
In this guide, we’ll walk through more real examples of retailers who’ve made the switch, and the practical steps to get from legacy debt to a modern system that scales with you.
A legacy system transformation is the process of replacing outdated technology with modern, often cloud-based systems. The motivation is not because something’s broken, but because an outdated system can limit future growth.
A transformation is more than an upgrade, such as updating a payment integration or switching email providers. Transformation considers all elements of your platform: how your systems are built, what they can connect to, and where your data lives.
Age isn’t the most useful way to identify a legacy system. A system may be considered legacy when it starts costing you more than it gives back. Here are some more specific indicators of a legacy platform:
Legacy modernization upgrades outdated software and systems to align them with current standards.
Transformation begins from the assumption that the underlying architecture itself needs to change. For commerce teams, that often means rebuilding around modular, API-first services that can connect to anything.
Here’s a quick overview of the difference:
| Modernization | Transformation | |
|---|---|---|
| What’s the primary goal? | Extend the life of existing assets | Fundamental shift to a new architecture |
| What’s the approach? | Small, low-risk updates or wrapping old code in new interfaces | Replacing or rebuilding the system from the ground up |
| What’s the risk level? | Low; less disruption to daily operations in the short term | High; requires significant data migration and process changes |
| What’s the expected outcome? | Improved performance and connectivity | Agility, scalability, and AI-readiness |
| What are some constraints? | Often preserves the underlying limitations of the old system | Removes old constraints to allow for innovation |
So, when is modernization enough, and when is transformation required?
Though transformation may sound intimidating, it can be well worth the effort.
Skullcandy proved this by moving to Shopify in just 90 days with immediate results: homepage load times plummeted from 2.8 seconds to 0.8 seconds. This technical agility translated directly to the bottom line, driving 45% YoY holiday revenue growth and maintaining 100% uptime even during a 200% traffic surge.
“With Shopify, we feel future‑proof,” says Brian Garofalow, CEO of Skullcandy.
According to projections, global ecommerce is on track to hit $8 trillion by 2028, with mobile commerce projected to account for 63% of those online sales. That’s a massive volume of transactions flowing through infrastructure that, for many brands, was never architected to handle what’s being asked of it now.
Take a look at the numbers:
Among the top 10,000 ranked sites, roughly brands doing more than $50 million in GM, 42.2% of new enterprise launches in the past two years chose Shopify.
That’s the phenomenon called “the enterprise exodus“—a sustained, accelerating departure from legacy commerce platforms.
The themes from brands making the switch are consistent:
Take The Conran Shop. The luxury homeware brand, founded over five decades ago by Sir Terence Conran, had built their ecommerce business on Magento, accumulating customizations over the years until the platform became more of a burden than an asset. The team was spending more time on site maintenance than on building customer experiences.
They made the decision to replatform to Shopify, guided by a simple mandate: reduce complexity, reduce cost, and reduce effort.
Since the migration, The Conran Shop has seen a 50% reduction in total cost of ownership (TCO), a 54% increase in conversion rates, and a 23% lift in email marketing revenue. They’re now exploring AI integrations—something that wasn’t on the table when their energy was consumed by keeping the old platform alive.
“For a high-consideration proposition like The Conran Shop, [unified commerce] enables customers to be much more seamless in the way they move between the online and in-store experience, whereas before it was totally separated,” says Richard Voyce, digital director of The Conran Shop.
Legacy technology shows up in the friction of your daily operations, and the compounding effect of technical debt can be seen in these patterns:
Check if any of the above apply to your current stack. If you check more than two, you’re likely losing market share to more agile competitors.
Mendix proposes three useful frameworks for legacy system transformation. Applied to commerce, these approaches can help you transform without lots of expensive downtime.
With this approach, instead of ripping out the old system, you build a modern shell around it. You use APIs to connect the old core to new front-end experiences. Over time, you “strangle” the old system by moving functions out of it one by one until the legacy core is gone.
Trade-offs: You’re still paying to maintain the old system while building the new one. If you don’t keep moving, you end up with legacy 2.0—a new front end stuck to a broken back end.
Here, you migrate your data and core business logic from a legacy, on-premise system—like an old version of Magento or a custom .NET build to a modern, multi-tenant SaaS platform like Shopify. The architecture changes, but the migration is structured around the platform switch rather than a ground-up rebuild.
Framebridge, for example, ran on a homegrown open-source platform for nine years before replatforming to Shopify. Their team described spending more time maintaining the platform than building on it, with a fragmented tech stack that couldn’t support the omnichannel expansion they needed.
After migrating, they’re now running more than 30 stores across the US on a single platform, managing over 250 retail staff, and have seen a 7.5% increase in overall conversion rate.
“Now that we’ve proven out the direct-to-consumer business and successfully tested retail, our plan is to scale both sides of the business in a very omnichannel way. We call it ‘Framebridge 3.0,’ and we think of Shopify as a critical foundation for us to achieve that scale,” shares Brian Bergman, senior director of product.
Trade-offs: You might lose some hyper-specific custom workflows that the old system had, requiring you to adapt your business processes to the new platform’s standard way of doing things.
This is sometimes identified as the “best-of-breed” or MACH (Microservices, API-first, Cloud-native, Headless) approach. You break the monolith into independent pieces: You might use one provider for your cart, another for your search, and yet another for your content.
This may be the best option for enterprise-scale retailers who need total control and want to be able to swap out individual parts of their stack without affecting the rest.
Trade-offs: Extreme complexity. You now have multiple vendors to manage, and your internal team must be highly skilled at managing integrations and APIs.
Tip: Shopify’s composable architecture offers modularity that lets you adopt it as much or as little as you want, while taking on hosting, security, updates, support, and unlimited scale. That means you can use Shopify as a stable, high-performance commerce core, while connecting best-of-breed tools for your content management system (CMS), PIM, search, or personalization around it via APIs.
In commerce, a legacy transformation is a high-stakes surgery performed on a living, breathing business—you can’t simply “turn off” the store.
Follow these five phases to help your transformation:
Consider mapping every system that touches commerce, and assessing each one against five criteria:
Here are some outcomes worth defining at this stage:
Write these down as measurable outcomes, tied to owners and timeframes. They become your filter for every subsequent decision in the roadmap, so if an architectural choice doesn’t move one of these numbers, question whether it belongs in your scope.
Now that you know what you’re solving for, choose the model that fits your team’s technical maturity:
For example, Taschen, the art and photography publisher with 11 stores across the world’s major cities, needed to translate four decades of brand prestige into a digital experience that felt worthy of the brand. Using Shopify headless, they went from conception to go-live in five months.
They saw 20% year-on-year revenue growth, a 6% higher average order value, and a 12% increase in total orders.
A migration plan for a commerce platform has four distinct workstreams that need to run in parallel.
Tip: Learn more about how to migrate your store to Shopify from another platform.
The technical migration is one part, but you also need to manage the organizational change that runs alongside it.
Read more: Change Management in Retail: A Corporate Guide (2026)
The US GAO has studied legacy modernization failure patterns across the federal government and consistently reached the same conclusion: Incomplete planning is the primary driver of cost overruns, schedule delays, and project failure.
According to government and industry best practices, documented modernization plans should include, at a minimum:
The lesson isn’t specific to government. Inadequate planning can lead to the following issues:
British heritage brand Belstaff migrated to Shopify to unify point of sale (POS) and ecommerce and break free from what their Director of Technology Navid Jilow described as a “black box” architecture with mounting technical debt.
The resistance they anticipated didn’t materialize the way they’d expected.
“Sometimes, you get a level of resistance during a new implementation. That’s why system intuitiveness is essential,” says Navid.
“The user interface of Shopify was a real highlight. When I looked at it I was like, ‘Okay, I can actually pick this up really quickly.'”
Employees who had previously depended on external support were able to engage with the new system confidently, without a prolonged onboarding runway. The right platform reduces the change-management burden.
Read Belstaff’s complete success story here.
Learn more: Avoid Digital Transformation Failure: 7 Mistakes Enterprise Commerce Leaders Make
Shopify doesn’t replace your ERP, your WMS, or your OMS—those systems stay. What it does replace is the part of your stack that tends to be the most expensive to maintain and the most painful to change: the commerce front end.
How it works: Your ERP and OMS connect to Shopify via API. Shopify supports integrations with leading ERP solutions including Oracle NetSuite, Microsoft Dynamics 365 Business Central, and others, with prebuilt connectors available through middleware platforms that handle data flows between systems in real time rather than overnight batches.
The ERP keeps its job as the source of truth for inventory, pricing, and financial data, and the WMS keeps managing fulfillment. But the commerce layer moves to Shopify.
You get a checkout that’s maintained, optimized, and scaled by Shopify rather than your internal team.
Research from a leading global management consulting firm found Shopify’s checkout outperforms competitors by up to 36%, with an average uplift of 15%.
Shop Pay, Shopify’s accelerated checkout, serves over 100 million users; customers who’ve already saved their payment details can complete a purchase in a single tap, without reentering anything.
You also get better than 99.9% uptime and infrastructure that’s been tested at scale. Shopify has handled 40,000 checkouts per minute without issue.
How it works: Hydrogen, Shopify’s React-based framework purpose-built for headless storefronts, can be deployed on Oxygen—Shopify’s globally distributed hosting with over 285 points of presence, at no additional infrastructure cost.
Shopify’s Storefront API is the foundation of its headless platform and is agnostic to all frameworks, devices, and service platforms, giving developers the freedom to use the tools they already know.
The practical advantage here is that you get architectural freedom without building the entire engine—checkout, payments, fraud, tax, and compliance stay with Shopify. Your team owns the experience layer; and Shopify’s composable architecture lets you adopt as much or as little of the platform as you want; using it as a complete solution or as a foundation for a wider web of best-of-breed tools.
Read more: What Is Composable Commerce—Is It Right for You?
How it works: Shopify includes hosting, security, updates, support, and unlimited scale as a standard.
A benefit of moving to Shopify is that security patches, PCI compliance, platform updates, and infrastructure scaling during peak—these move from your internal engineering backlog to Shopify’s.
A platform migration doesn’t eliminate complexity, but it does redirect it.
Dollar Shave Club, for example, migrated from a homegrown platform to Shopify and cut tech spend by 40%.
“Sometimes, there’s a misconception that building something in-house means it’s free in the long run. But developing it diverts resources from other important projects, and maintaining it isn’t free either,” shares Kyle Iwamoto, vice president of ecommerce.
And Carrier now launches ecommerce sites 90% faster at 10% of the cost with Shopify.
“If you want lower TCO, rapid deployment, and a platform that is growing at a rate faster than you can develop it yourself, then I would encourage you to look at Shopify,” says
Steve Duran, associate director of global commerce.
This is what happens when an engineering team stops spending half its time keeping the lights on.
Legacy system modernization is the process of updating, transforming, or replacing existing systems so they can meet current and future business needs. Modernization efforts typically involve changes to the underlying architecture, the technology stack, the integration approach, or all three.
In practice, modernizing legacy applications can take several forms depending on how broken the existing system is and how much risk the business can absorb.
For commerce specifically, legacy application modernization usually starts with the storefront and checkout before moving deeper into back-office infrastructure.
A legacy system is any technology—software, hardware, or platform—that a business still depends on for core business operations despite being outdated, unsupported, or incompatible with modern tools.
A system becomes a legacy system when it limits what the business can do, when existing code is too fragile to change safely, when integrations keep breaking, or when the cost of keeping it running outpaces the value it delivers.
Typically, yes. But the honest answer depends on what you’re replacing it with and why. The cost of not replacing legacy systems compounds over time as operational costs rise, security exposure grows, and the opportunity cost accumulates every time a new market or channel requires a six-month IT project.
It depends on which version you’re running. SAP S/4HANA, SAP’s current cloud ERP platform, is a modern system. SAP ECC—the version that has powered enterprise operations for decades—is now widely considered legacy.
At the end of 2024, only 39% of the 35,000 SAP ECC customers had migrated to S/4HANA, according to Gartner, which projects that more than a third will still be running ECC in 2030.
Inertia, cost, and risk—in roughly that order.
Legacy systems are often deeply embedded in core business operations, with years of customization, integrations, and institutional knowledge built around them.
