Custom theme development
No off-the-shelf template. We build themes from scratch on your design system, built around checkout, B2B, and Markets from day one.
Shopify Plus storefronts thatconvert at scale
Custom storefronts for Plus brands, built around checkout, B2B, and Markets. Every change ships as a test, so you know what moved revenue.
Plus storefronts we ship with
Scope of services
Which services are part of a Plus storefront?
Custom themes, optimization, and Plus features in one build. Not a Dawn template with apps stacked on top.
Theme optimization and conversion
Fast theme, flat conversion? We audit, cut the weight, and A/B test every fix so you know what actually moved revenue.
Plus customization and features
Checkout extensions, B2B portals, Markets, and metaobjects. The parts of Plus you are paying for and probably not using yet.
Why custom
Why do storefront rebuilds not move revenue?
Nobody can attribute the lift
The site was rebuilt, revenue moved a little, and no one can say which change did it.
The app stack patched every gap
Every missing feature became another app, and each one ships its own JavaScript into your checkout path.
Plus is paid for, not used
Checkout extensions, B2B, and Markets sit idle while the theme works around them.
The handover was a folder of files
Undocumented code, one person who understands it, and a quote for every small change after launch.
Every change ships behind a test
Releases go out as A/B tests in Intelligems, not as opinions. On Clean Skin Club every change ran against a live control, so revenue movement was attributed to the test, not the rebuild.
Instrumentation before optimization
We fix the data layer first with PostHog and server-side events, so purchase, identity, and source survive the whole funnel. You cannot optimize what you cannot attribute.
Plus capabilities built into the theme
Checkout extensions and Shopify Functions, B2B price lists, Markets, and metaobjects developed inside your storefront instead of added as another subscription.
We build the app when the theme is wrong
Some problems are not theme problems. We ship custom Shopify apps and have our own live on the App Store, so the recommendation is never bent to fit what we can build.
Our approach
How a Plus storefront project runs with us
- 01
Look at what exists
We audit the theme, Plus features, and the templates that carry revenue. Clear list of leaks before any build starts.
- 02
Sharpen the scope
Theme work is separated from app work. Scope often shrinks here, so you are not paying for a rebuild you do not need.
- 03
Design the system
Sections, tokens, and Plus integration (B2B, markets, checkout) are locked before development. The buying journey is set before visual polish.
- 04
Build in a theme copy
Custom Liquid and Plus features land in an unpublished theme. Each change is tested and documented. Nothing breaks in production.
- 05
Check, launch, hand over
Core Web Vitals, Plus feature QA, and a controlled go-live. You get documented code your team can keep working with.
Fit
Is a Plus storefront rebuild your next step right now?
Then you are starting in the right place
You are paying for Plus and using a fraction of it
Checkout extensions, B2B, and Markets are on your invoice every month. If the theme cannot address them, you are funding capability you never ship.
Your theme is a stock theme with twenty apps on top
Every gap got closed with a subscription. The scripts stack up in the same critical path, and no one owns the total anymore.
Every campaign needs a developer
A new landing page or a seasonal section turns into a ticket and a wait. Without a component system, marketing moves at development speed.
You cannot run a test without a rebuild
If trying a different PDP layout means touching production code, you will not test often enough to learn anything.
Then something else will do more for you
Liquid is the ceiling, not the theme
If your frontend needs interactions and content flows Liquid cannot express, a better theme will not get you there. That is a headless question.
To headless storefrontsThe problem lives inside checkout
Custom discount logic, upsells, and validation at the checkout steps run through Extensions and Functions. The theme around them is not the constraint.
To checkout and extensionsThe work is data moving between systems
ERP, PIM, fulfillment, and order flows are integration problems. Rebuilding the storefront does not fix what happens after the order.
To agentic integrations
Engagement
How can we work on your Plus storefront together?
Whether you need a custom theme, optimization of an existing storefront, or ongoing Plus work, the shape is scoped after we see the store.
Custom theme development
Scoped after we review the store.
Who it is for
For Plus brands that need a custom theme built around their catalog, customer experience, and business requirements. When a stock theme no longer matches how you sell.
What is included
- Discovery, UX strategy, and conversion-focused design
- Custom theme development with Plus feature integration
- Performance optimization, QA, and launch support
How it ends
Ends with a live theme optimized for your Plus capabilities and a handover your team can manage.
Theme optimization
Scoped to the leaks we find.
Who it is for
For stores with an existing theme that need speed, conversion work, or Plus feature integration without a complete rebuild.
What is included
- Theme audit, performance analysis, and conversion bottleneck identification
- Speed optimization, UX improvements, and Plus feature integration
- A/B testing setup and post-optimization performance tracking
How it ends
Results in measurable performance and conversion improvements with clear before and after metrics.
Plus customization retainer
Monthly. Three months minimum for meaningful results.
Who it is for
For teams that need ongoing Plus development, checkout extensions, B2B features, and continuous conversion work.
What is included
- Sprint planning focused on Plus capabilities and revenue goals
- Checkout extensions, B2B portal development, and market expansion features
- Performance monitoring, conversion optimization, and rapid deployment of improvements
How it ends
Runs as an ongoing partnership with documented releases and clear ROI measurement.
Not sure which shape fits? Book a meeting with the team.
Not ready to book?
What our customers say
“We're the #1 face towel on Amazon, but our Shopify offers were too slow and confusing. They rebuilt for speed, fixed our subscription flow, and our online revenue is now growing 18%.
Complementary services
What works alongside Plus storefronts
Plus storefronts often need additional capabilities. These services frequently pair with custom theme development.
We integrate the apps already in your stack.
Testing, subscriptions, email, loyalty, and search connect into a custom Plus theme. They do not stand in for one.
FAQ
We run releases as A/B tests in Intelligems rather than shipping and hoping. A variant runs against a live control until the result is stable, and you see the split. That is how the Clean Skin Club checkout work was measured. It also means we sometimes tell you a change we built did not win, which is the point of testing it.
Plus storefronts vary by catalog, checkout, markets, and B2B. A published starter number would either under-scope the work or over-promise a template rebuild. You get a scoped number after we look at the store. Use the budget field so we know the range you are working with.
No. Custom theme work can happen on standard Shopify. Plus is worth it when you need checkout extensions, native B2B, markets, or the higher API limits those features require. If those are not in the plan, we will say so.
Fine either way. We often run alongside an in-house team, taking the Plus and checkout work while they keep the day-to-day theme. If you already have an agency, we scope narrowly around what they are not covering rather than asking you to switch. Everything is documented in your repo, so nothing we build depends on us staying.
A theme with a clear section structure is finished sooner than one with checkout extensions, B2B, and connected systems. Typical custom themes take 4 to 8 weeks including discovery, design, development, and testing. We only give a firm date once scope and the system landscape have been reviewed.
The theme is yours. You get the repo, documented Liquid, and a walkthrough with whoever will maintain it. We do not hold the code hostage or charge for access. If you want us to keep going the retainer exists, and if you do not, your team or another agency picks it up without calling us.
Let's meet
Looking to scale revenue on Shopify? You'll book directly with Dusan J., Founder at EXTFOX, to discuss your store, opportunities, and next steps.
Tell us about your store
Pick a time that works for you. You'll get instant confirmation and a calendar invite.
Prefer to call? (862) 259-6969
Not ready to book?
Last updated: August 2026