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18 · Shopify Development

Shopify development agency for custom themes, store builds, and migrations that convert.

A Shopify development agency for custom theme development, store redesigns, app work, and WooCommerce or Magento migrations. We ship Online Store 2.0 stores that paid media can scale into — not a Dawn child theme with twenty apps.

Faster store. Cleaner cart. Higher conversion on the same traffic.

OS 2.0 themesStore & cartCustom appsMarkets · wallets · tax
  • P&L desk
  • Reply in one business day
  • 30-min working session

Desk fact

OS 2.0

Custom sections merchants can edit — Dawn is a starting point, not the product.

Desk fact

One desk

Store, pixels, and paid media. We do not hand you a rebuild and vanish.

Desk fact

+649%

Lightspares gross sales in 6 months after catalog and store work.

Shipped storefronts

Websites we built.

Live Shopify stores on this desk. Visit the site — the work is on the domain, not a mock.

  • Snuggle & Hush Shopify homepage: Halloween kids pajamas hero with Spooktacular Prints headline.

    Kids apparel

    Snuggle & Hush

    Shopify storefront for seasonal kids pajamas.

    Visit the website
  • Dharan Clothing Shopify homepage: Print Charm hero with lifestyle photography and Shop Now.

    Fashion

    Dharan Clothing

    Shopify storefront for print-led apparel.

    Visit the website

Direct answer

What does a Shopify development agency do?

A Shopify development agency designs, builds, and maintains Shopify stores — custom theme development, store redesigns, apps, and migrations — so the storefront converts the traffic you already paid for. SpikeROAS is that desk with a P&L attached: Online Store 2.0 themes, cart and PDP work, and the pixels that paid media actually needs.

Most Shopify agencies ship a Dawn child theme, install a pile of apps, and call it a launch. Then the cart is a receipt, LCP is four seconds on mobile, CAPI is missing, and Google Shopping is bidding on a dirty feed. I built this desk because we kept inheriting stores that looked finished in a portfolio and died the week media scaled.

Checkout has to match the market that is actually buying: Shop Pay and sales tax in the US, VAT in the UK, GST and UPI in India, Afterpay in Australia. Not a USD theme with a currency app. If you need Checkout Extensibility, Shopify Functions, or native B2B, that is Shopify Plus development — a separate build, not a theme upsell.

Related: Shopify Plus development, ecommerce and DTC, CRO, performance marketing, and store and media results.

Fit

Who this Shopify development agency is for

Merchants who have outgrown a theme install and operators who need the store, the feed, and the ads on one scoreboard. If you only need a $2k Dawn skin, hire a freelancer.

DTC and catalog brands

Physical products on Shopify, enough media that a slow PDP actually hurts. Custom Shopify theme development and store redesign when the theme editor cannot express the brand — not because a deck said 'bespoke.'

Migrations and replatforms

WooCommerce, Magento, BigCommerce, or a custom stack that is expensive to keep alive. Products, customers, orders, and SEO redirects — not a pretty homepage with 404s behind it.

Stores that media cannot scale into

You are already buying Google and Meta. The leak is PDP, cart, or speed. That is a Shopify development job sitting next to CRO and paid — see ecommerce if the P&L is the brief.

Who we will not take

  • Dropship lottery stores and 'I saw a theme on YouTube' briefs. We will say no on the call.
  • Merchants who will not share margins, AOV, or the conversion number that has to move.
  • Teams that want Hydrogen because it is fashionable. We pitch headless when Liquid cannot do the job.
  • Agencies shopping for unpaid white-label theme labour with no access to the merchant.

The leak

What typical Shopify agencies get wrong

Theme-led, not conversion-led

Hero sliders, parallax, and a portfolio shot that tanks add-to-cart. We start from the funnel: collection → PDP → cart → checkout. Every section has to earn a metric or it does not ship.

App soup instead of engineering

Twenty apps for what Flow and a private app should do. Each app is a request, a discount conflict, and a future break. We cut what does not pay rent.

Speed treated as a post-launch ticket

LCP over two seconds on mobile is a tax on every ad dollar. We set a Core Web Vitals budget before sections ship. Theme awards do not pay the CPC.

One English theme, five markets

Shop Pay, VAT, India COD, and AU Afterpay are not a currency toggle. We build the store for the market that is actually buying — wallets, tax, and shipping promises that match the checkout.

On the desk

Shopify development services on the desk

Theme, store setup, custom apps, and migrations live here. Checkout Extensibility and native B2B live on Shopify Plus development.

Custom Shopify theme development

Online Store 2.0 sections and blocks your merchandising team can edit. Liquid done as software, not glued snippets. Mobile-first PDPs, collection filters, and a cart that sells a second item. Dawn is a starting point, not the product.

Shopify store setup and redesign

New stores and rebuilds of stores that look launched and leak. Catalog structure, navigation, PDP proof, and a cart drawer that is not a receipt. Redesign means conversion, not a new font.

Custom Shopify development

Private apps when the App Store cannot do the job. Cart drawers, bundles, subscriptions, ERP, 3PL, Klaviyo, and server-side CAPI. GraphQL and Liquid as software, not a first-time experiment on your live theme.

Shopify migration and replatforming

Catalog, customers, orders, URLs, and 301s from WooCommerce, Magento, or BigCommerce. SEO equity is a deliverable, not a hope. We cut over with a redirect map and a tracking checklist, not a 'we will fix rankings later.'

Shopify Plus development

Checkout Extensibility, Shopify Functions, native B2B, and Plus migrations are a different build. If that is the brief, start with Shopify Plus development — we will not sell Plus as a theme upsell.

Performance, CRO, and the handoff to ads

LCP, INP, and CLS as a launch gate. Pixels, Enhanced Conversions, and CAPI in week one. Then conversion-rate optimization and performance marketing on the same desk so the rebuild is not an island.

Markets

Shopify development for the market you actually sell

Tax, wallets, and shipping have to be local. We run one engineering OS. We do not paste one storefront into five countries and call it international.

Market

United States

Shop Pay, Shopify Payments, sales tax, and Merchant Center feeds that Shopping can actually use. Hardware-scale catalogs — we have run Google Ads on a Florida hardware brand to $2.65M at 3.91x ROAS, which only holds if the store and feed are honest.

Market

United Kingdom

VAT, Shopify Payments UK, Royal Mail, and Clearpay/Afterpay where the offer needs it. Theme and checkout in GBP, not a USD store with a converter.

Market

Canada

GST/HST by province, Interac, Canada Post / Purolator, and bilingual storefronts when Quebec is in the brief. Markets and duties set correctly so a Toronto checkout is not a New York checkout with a maple sticker.

Market

India

GST invoices with HSN, Razorpay / UPI, COD with OTP, Shiprocket, and no-cost EMI. A US theme with a rupee symbol is not an India store.

Market

Australia

GST, Afterpay, Australia Post, and Shopify Payments AU. Theme and checkout built for AU mobile and AU shipping promises — not a US store that 'also ships to Sydney.'

The work

What we actually do

  • Custom Shopify theme development on Online Store 2.0 — sections merchants can edit without breaking the build
  • Shopify store setup and redesign: PDPs, collections, cart drawers, and a funnel that matches the ads
  • Migrations from WooCommerce, Magento, and BigCommerce with redirects, customers, and orders intact
  • Private apps, cart drawers, bundles, and ERP / 3PL / Klaviyo / CAPI integrations
  • Performance budget: LCP, INP, CLS — Core Web Vitals as a launch gate, not a post-launch firefight
  • Checkout, tax, Shop Pay, and Merchant Center feeds — plus local wallets when you sell UK, Canada, India, or Australia

Deliverables

You leave with

  • Architecture and conversion brief (theme vs custom vs migration)
  • Staging theme on your store, in your name
  • Migration map: URLs, redirects, catalog, customers
  • Launch checklist: pixels, CAPI, Shop Pay, speed

Ready to brief the Shopify Development desk?

Send the Shopify admin URL (or a staging preview) and the number that has to move. We will tell you what we would build — and what we would not.

Schedule a call

Cadence

How the work runs

01

Audit the store, not the moodboard

Theme debt, app soup, cart leaks, and the number conversion has to move.

02

Build what the P&L needs

OS 2.0 theme, custom sections, or a migration — Plus work lives on the Shopify Plus development desk.

03

Launch and hand to media

Tracking live. Speed green. Then CRO and paid can actually scale.

First 90 days

First 90 days on a Shopify build

Days 1–14

Audit the live store

Theme, apps, cart, speed, tracking, and the conversion number. Kill list of apps and Liquid debt. Architecture call: OS 2.0, custom app, or migration. Plus checkout is a different brief. You get the plan before we write a section.

Days 15–45

Build on staging

Theme or checkout in your store, in your name. Catalog and redirect map if this is a migration. Weekly staging URL. No surprise 'big reveal' at week eight.

Days 46–75

QA, speed, and pixels

Core Web Vitals on real mobile. Shop Pay, local wallets, tax, and shipping. CAPI and Enhanced Conversions live so media is not blind at launch.

Days 76–90

Launch and hand to the P&L

Cutover, redirect QA, and a 30-day CRO + media plan. The store is not 'done.' It is ready to take traffic. If we are also the ads desk, week one of paid starts with a store that can convert.

The fork

SpikeROAS vs typical Shopify agency vs in-house

Hire us when the store has to convert paid traffic. Stay in-house when you already have Liquid engineers, a performance budget, and someone who owns the cart.

FactorSpikeROASTypical agencyIn-house
ScoreboardConversion, AOV, LCP, contribution after the rebuildTheme launch day and a Dribbble shotDepends on whether engineering reports to marketing
Theme vs customPremium OS 2.0 when it is honest; custom when the UX cannot live in the editorFrom-scratch Liquid to inflate the SOWUsually a child theme that accretes debt
After launchCRO and paid on the same deskMaintenance retainer and a ticket queueRoadmap fights with feature requests from every team
Plus workA separate Shopify Plus development page — not stuffed into a theme quotePlus logo on the website, Dawn under the hoodThin unless you hired Plus engineers
HeadlessHydrogen when Liquid cannot; honesty when it canHeadless pitched to inflate the SOWOften the right call if you already have React

Pricing philosophy

No fake menu. An honest gate.

Shopify development is scoped as a build — theme, redesign, migration, or a cart system — not a fake $3k menu. Custom theme work typically sits in the mid-five-figures once catalog and apps are real. Theme customizations can be less. Plus checkout and Hydrogen are a different quote on the Plus desk. We will not bid a migration like a color swap.

  • You own the theme, the apps, and the store. We do not hold the keys.
  • Theme vs custom vs migration is an architecture call on day one, not an upsell at week six.
  • Best with CRO and performance marketing so launch week has a readout.
  • Shopify Plus platform fees are paid to Shopify. Plus engineering is quoted on the Plus page.

The call

What happens in 30 minutes

  • 30 minutes. Working session on the live store — not a moodboard.
  • Plan, AOV, the conversion leak, and whether this is a theme, a migration, or Plus.
  • We will tell you what to build — or that a freelancer is enough.
Schedule a call

Proof we will publish

Case studies live here — with numbers, not adjectives.

Named shopify development work is going on Work as we can show it. Until then, ask on the call for the scoreboard in your category. We will not invent logos or fake ROAS.

  • Your ad accounts stay in your name
  • Weekly kill / hold / scale memo
  • A 30-minute working session, not a pitch deck

FAQ

Questions we get about Shopify Development

What does a Shopify development agency do?

A Shopify development agency builds and maintains Shopify stores: custom themes, store redesigns, apps, integrations, and migrations. SpikeROAS also runs CRO and paid media on the same desk so the store is scored on conversion, not on whether the theme looked good in Figma.

How much does Shopify development cost?

Theme customization often sits in the high four to low five figures. Serious custom theme work usually starts in the mid-five-figures once catalog and apps are real. Freelancer theme installs can be a few thousand and usually look like it. We quote after seeing the store — not from a public menu.

How long does it take to build a Shopify store?

A focused OS 2.0 rebuild is often 6–10 weeks after discovery. A full migration can run a quarter. App-only work (cart, bundles) can ship in days. Anyone promising a custom store in a week is selling a theme with extra steps.

Do you offer Shopify Plus development?

Yes — on a separate page. Shopify Plus development is checkout extensibility, Functions, B2B, and Plus migrations. If Plus is the job, start there. Theme work for a Plus store can still live here when checkout is not the brief.

Can you migrate from WooCommerce or Magento?

Yes. Products, customers, orders, and a redirect map so organic URLs do not 404. We treat SEO as part of the cutover. A homepage-only 'migration' that leaves your rankings on the old domain is not a migration.

Can you customize a theme or do you only build from scratch?

Both. We customize a premium OS 2.0 theme when it is the honest path, and we build custom when the brand or UX cannot be expressed in the theme editor. From-scratch is not a virtue. Conversion is.

Do you work on existing Shopify stores or only new ones?

Both. Most briefs are stores that already exist and leak: slow PDPs, a dead cart, dirty feeds, missing CAPI. We take over without a vanity replatform unless the theme is actually the bottleneck.

Do I need Hydrogen or headless Shopify?

Only if Liquid cannot deliver the UX, CMS, or performance you can measure. For most merchants, a fast Online Store 2.0 theme is cheaper to run and easier to merchandise. Headless on Plus is scoped on the Plus desk.

Do you build Shopify stores for more than one country?

Yes. Shop Pay, sales tax, VAT, GST, UPI, Afterpay — checkout and tax follow the market that is buying. We will not launch one theme into India and hope Razorpay just works.

Do you run ads after the Shopify store launches?

Yes. That is why this desk sits next to performance marketing, CRO, and email. A rebuild that never sees a media plan is a brochure. We will not vanish at launch day unless you only hired development — and we will still wire tracking as if media is coming.

Usually paired with

Other desks on the same P&L

Industries

Where this service actually runs

Next step

If the store cannot take the traffic, stop buying more of it.

Send the Shopify admin URL (or a staging preview) and the number that has to move. We will tell you what we would build — and what we would not.