Why homegrown commerce platforms aren’t built for enterprise scale — and what to do instead

Homegrown platforms: When control becomes constraint 

Businesses relying on a homegrown eCommerce platform have chosen control over creating their own solution over buying an unwieldy one from companies like Salesforce or SAP. It’s like every developer’s dream: To have the freedom to code their own solutions without constraints or costs from third-party vendors. 

And this might work for a while — until the company outgrows its custom-built commerce platform. And this is already happening, as 30% of businesses have moved away from in-house-built platforms to innovate faster, improve scalability and boost user experiences. 

Most in-house commerce systems were designed for a single channel, predictable traffic and a relatively static product experience. As digital commerce evolves — across mobile, marketplaces, social and now AI-driven commerce — these systems struggle to keep up.

What once enabled control begins to create friction:

• Every new channel requires complex custom integration.
• Every spike in traffic risks instability.
• Every feature competes with maintenance work.
• Every departure of a key engineer increases system fragility.

And in today’s environment, the gap only widens.

7 reasons why homegrown platforms become a bottleneck 

Many of the challenges of custom-built solutions start small and snowball over time. Collectively, they slow innovation, inflate costs and limit a company’s ability to capitalize on new opportunities — even more so in the era of agentic commerce. 

Reason #1: Limited flexibility and complex integrations 

Integrating new tools, channels or systems can become a painful and slow process. In addition, custom-built commerce solutions are usually monolithic, with all functionalities tightly coupled, missing the flexibility needed for customization. 

Impact:

• Lengthy integration cycles.
• Difficulty adopting new technologies.
• Data inconsistencies between systems.
• Slow or stalled omnichannel expansion.

Reason #2: Low performance and scalability limitations

Every system requires updates and adjustments over time. However, if developers don’t have time to keep the platform up to date — and the head engineer who created the original code leaves the company — businesses end up with a bowl of spaghetti code, characterized by a high number of bugs and bottlenecks, leading to patchy performance.

Like legacy on-premise systems, homegrown commerce platforms often require manual scaling or infrastructure interventions during surges.

Impact:

• Downtime during peak events.
• Sluggish performance.
• Revenue loss and poor customer experience.
• High operational overhead.

Reason #3: Loss of agility → missed revenue opportunities 

As homegrown platforms grow more complex, they become increasingly difficult to update or adapt. This slows your ability to respond to emerging customer needs, market shifts and new business opportunities. At the same time, modern shoppers expect fast, personalized and seamless experiences across every touchpoint — expectations most in-house solutions were never designed to meet.

Impact:

• Delayed product launches and slower experimentation with new business models. 
• Missed seasonal or trend-based opportunities.
• Difficulty implementing personalization, mobile responsiveness or new channels. 
• Lower conversion rates and increased customer frustration throughout the journey. 
• Falling behind more agile competitors. 

Reason #4: Slow time-to-market and innovation bottlenecks

Your developers are always busy maintaining the system. Enhancements must be routed through the same central engineering team, competing with bug fixes, maintenance and infrastructure work.

Impact:

• Slower releases.
• Backlogged roadmaps.
• Reduced experimentation.
• Teams stuck maintaining instead of innovating. 

Reason #5: Talent dependency, continuity risk and technical debt

Homegrown commerce platforms create a structural dependency on the engineers who originally built them. Because these systems are proprietary and highly customized, critical knowledge about how they work is often concentrated in a small group of individuals.

When those engineers leave or move on, organizations don’t just lose people — they lose context. The system becomes progressively harder to understand, evolve and safely modify, turning routine changes into high-risk engineering efforts.

Impact:

• Loss of critical system knowledge and context. 
• High dependency on original developers or a small expert group.
• Longer onboarding times and reduced hiring flexibility.
• Rising technical debt and accumulation of workaround solutions.
• Increased maintenance burden and engineering overhead.
• Long-term system fragility and operational risk.

Reason #6: Rising long-term costs

A bespoke commerce stack appears more affordable at the start. But costs rise sharply over time due to maintenance and infrastructure upgrades. 

Impact:

• Higher total cost of ownership.
• Ongoing refactors and re-architecture.
• Security and compliance overhead.

Reason #7: Not built for AI or agentic commerce

The upcoming pitfall: Homegrown platforms cannot evolve fast enough for the age of AI.

The shift toward agentic commerce — where AI agents autonomously assist customers, optimize catalog logic, personalize journeys and automate operations — requires an architecture that’s modular and API-first. 

Impact: 

• Delayed implementation of agentic workflows. 
• Massive opportunity loss in the years ahead.

What modern commerce looks like — and how commercetools makes it happen

Modern enterprises are shifting away from bespoke commerce stacks toward a more resilient model: Modular commerce.

In this model:

• Businesses build what differentiates them.
• They buy standardized capabilities (checkout, payments, CMS, search).
• They unify everything through a scalable, API-first foundation.

This shift allows enterprises to move faster, scale more reliably and adapt continuously as customer expectations evolve, especially as commerce becomes increasingly AI-driven and channel-agnostic.

The result is a commerce architecture that’s no longer a constraint, but a growth engine.

commercetools provides a flexible commerce foundation designed specifically to operationalize this model, without the constraints of bespoke or custom architectures.

Unlike traditional SaaS platforms or homegrown stacks, commercetools enables enterprises to:

• Integrate commerce capabilities independently, rather than rely on fixed suites.
• Scale globally without re-architecting core systems.
• Integrate seamlessly into existing technology ecosystems.
• Continuously evolve without downtime or disruption.

In more detail:

Built for flexibility, adaptability and extensibility: commercetools enables enterprises to model commerce around their unique requirements, deploy changes incrementally and extend capabilities modularly without replatforming cycles or introducing architectural complexity.

Future-proof by design: commercetools’ architecture removes the “SaaS vs. custom” and “build vs. buy” trade-offs by providing a modular commerce foundation that evolves continuously with business needs, channels and emerging AI-driven commerce models.

Secure, scalable, performant and always-on: commercetools delivers enterprise-grade reliability with high-performance APIs, elastic scalability for global traffic and catalog growth and always-on infrastructure designed to maintain stability during peak demand.

AI-first unified commerce: commercetools’ unified commerce platform centralizes product, pricing, inventory and order data into a real-time foundation, enabling consistent omnichannel experiences and powering AI agents (e.g., ChatGPT, Gemini, Copilot) with accurate, actionable signals for shoppable and autonomous journeys.

Proven partner in enterprise commerce: commercetools supports complex global transformations with deep migration expertise, enterprise-grade operational reliability and a track record of enabling large-scale commerce modernization across industries.

Enterprises that migrated from homegrown platforms to commercetools 

For the majority of companies that invested time and money in a custom-built commerce platform, transitioning to a modern approach proved to be the optimal solution. Here’s how B2B organizations Adelco and BIC, as well as retailers Interflora UK and Moonpig, benefited from the switch. 

Adelco modernized its channels and boosted eCommerce sales by 400%

Adelco initially built several in-house digital tools — an eCommerce site, a customer app, and mobile apps for sales reps and drivers — to keep operations running during lockdowns. But because these solutions were created quickly and without a long-term strategy, they became rigid and disconnected over time. Sales reps couldn’t customize their app experience, the systems weren’t integrated with the eCommerce shop and the lack of real-time stock visibility frequently disrupted fulfillment.

By adopting the commercetools platform, Adelco integrated four core digital and in-person channels into one connected ecosystem. This shift enabled them to transition from a solely in-person model to a true omnichannel approach, offering self-service, assisted and in-person sales options. 

The result: +400% eCommerce sales, +20% conversion rate and +25% SKUs per order for self-service buyers.

BIC unlocked global scalability with a composable architecture

Previously, BIC’s B2B commerce ran on inflexible eCommerce systems developed in-house that required extensive manual processes — even managing orders in spreadsheets. As BIC expanded and regional needs diversified, its in-house built commerce system couldn’t keep pace with rapidly changing business requirements.

With commercetools, BIC decoupled its frontend and backend, enabling region-specific catalogs, promotions and integrations through an API-first approach. Now operating a single storefront that supports six currencies across 100+ countries and serves 150+ B2B customers, BIC has already gone live in the MEA region and is preparing to launch in the US. The new platform delivers greater agility, reduced downtime and the flexibility to scale globally.

Interflora UK reduced hosting costs by 20% after ditching its DIY platform

The leading flower delivery network, Interflora UK, invested early in eCommerce with an in-house built platform. Over time, the company’s in-house platform became rigid and expensive, with the company maintaining a costly year-round high-availability hosting service to accommodate just three seasonal spikes: Valentine’s Day, Mother’s Day and Christmas. Furthermore, the company struggled with a rigid, custom-built commerce platform that hindered mobile responsiveness and SEO performance. 

By modernizing its tech stack with a modular approach, Interflora UK improved its website performance and mobile-first customer experience while reducing its annual hosting costs by 20%. Additionally, the company had to contend with sluggish performance, achieving zero downtime across three web shops.

Moonpig broke free from technical debt and accelerated time to market

Moonpig originally built its own end-to-end platform, responsible for everything from frontend experiences to card printing. Over time, this custom-built commerce platform system became too inflexible to support new feature development and accumulated technical debt slowed teams down with maintenance, bug fixing and infrastructure management — especially as traffic and order volumes grew.

By shifting to a modular commerce architecture, Moonpig began breaking down its monolith into modular capabilities and invested engineering effort only where it differentiated. The company built a tailored stack using commercetools B2C Commerce, Adyen and Contentful, combined with custom applications. 

This flexibility dramatically improved delivery speed, enabling Moonpig to launch new features, such as a mobile app with personalized journeys and AI-powered tools for message writing, far faster than before.

From homegrown to home run: The path forward

Building a custom commerce stack may seem appealing — the control, the customization, the ownership. But modern commerce requires more than customization. It demands: 

• Agility and speed. 
• The ability to innovate fast. 
• Scalability.
• Low total costs of ownership (TCO). 
• AI readiness. 

Modern commerce gives you all of this without forcing you to give up control as you choose what to build and what to buy. 

Long story short: You create a platform as unique as your business without carrying the full burden of maintaining commoditized infrastructure.

Ready to reclaim agility and future-proof your commerce stack? Download the migration guide and learn how your business can move from in-house-built solutions to commercetools. 

FAQs

How do homegrown platforms impact business agility and scalability?

They slow down time-to-market for new features and deployments, complicate integrations and make it difficult to scale efficiently during peak demand.

What should businesses consider when deciding to build or buy?

Consider long-term maintenance, total cost of ownership, technical debt, internal expertise and future adaptability, including AI readiness.

Is building an in-house eCommerce solution cheaper?

Short term, possibly. Long-term, almost never. Technical debt, maintenance and scalability challenges make custom-built commerce platforms more expensive over time.

What are the main advantages of modular commerce over homegrown platforms?

Modular commerce offers modularity, faster innovation, lower long-term costs and future-proof flexibility, including for emerging agentic-driven experiences.