Shopify Technical Services
Senior Shopify development for merchants who need a store that's fast, customized, and built to scale — from Liquid theme work to full headless Hydrogen builds and Shopify Plus migrations.
Built for merchants, not template buyers
Most Shopify stores hit a ceiling — the theme can't do what the brand needs, page speed tanks after the fifth app, or a Plus migration requires custom checkout logic. We're the team you bring in when off-the-shelf stops working.
Every engagement is led by a senior Shopify engineer. No outsourcing, no hand-off to a junior, no "we'll learn it on your project." We've shipped on Online Store 2.0, Hydrogen, the Checkout Extensibility platform, and against the GraphQL Admin API — and we know where each one breaks.
What's included
Theme engineering
Custom Liquid sections, blocks, and Section Groups — built against Online Store 2.0 standards.
Headless & Hydrogen
React-based storefronts on Hydrogen / Remix with Oxygen deployment and Storefront API.
Checkout extensibility
Checkout UI Extensions, Functions for discounts/shipping/payments, branded one-page checkout.
Performance & CWV
Core Web Vitals tuning — LCP, CLS, INP — to take Lighthouse from 50s into the 90s.
App integration
Third-party app integration, private/custom apps, webhooks, and Admin API automation.
Shopify Plus migration
Replatforming from BigCommerce, WooCommerce, or Magento to Shopify / Plus with zero SEO loss.
Typical deliverables
- Production-ready theme code in a Git repository (GitHub / Shopify CLI workflow)
- Documentation for every custom section, block, and metafield
- Before/after Lighthouse and Core Web Vitals reports
- QA across major browsers and devices (BrowserStack)
- 30-day post-launch warranty on shipped work
- Knowledge transfer session with your internal team
How we work
Discovery sprint
A paid, fixed-price sprint of 1–2 weeks. We audit your store, document scope, and hand you a written technical proposal with a firm price.
Backlog and plan
We turn the proposal into a shared backlog with priorities and estimates, so you see exactly what's being built, when, and at what cost.
Build in 2-week sprints
Development happens in a separate theme or development store via Shopify CLI, with code review on every change and publishing only after your sign-off.
Handover and warranty
You get documentation for every section and metafield, a knowledge transfer session with your team, and a 30-day post-launch warranty.
How we compare
| What you get | Feerr Tech | Typical freelancer | Big agency |
|---|---|---|---|
| Senior engineer on every task | Yes | Sometimes | No |
| Git workflow with code review | Yes | Rarely | Yes |
| Fixed-price discovery before commitment | Yes | No | No |
| Direct contact with the person building | Yes | Yes | No |
| 30-day post-launch warranty | Yes | No | Varies |
FAQ
Do you work directly in our Shopify store or in a staging environment?
Both. We develop in a separate theme or development store using Shopify CLI, code-review every change, and only publish to your live theme after sign-off. For Plus, we use development stores tied to your organization.
Can you work with our existing theme, or do we need a rebuild?
Whenever the existing theme is on Online Store 2.0 and reasonably well-structured, we extend it rather than rebuild. We'll tell you honestly in the discovery sprint if a rebuild would actually save you money over the next 12 months.
How do you handle Core Web Vitals on stores with lots of apps?
Audit first: we measure real user data via CrUX and synthetic data via Lighthouse, identify which apps inject the most JS/CSS, and either defer them, swap them, or replace with native theme code. Most stores recover 20–40 points without removing functionality.
Do you also do design?
We are an engineering team. We work well with your designer or design agency, and we can recommend partners we trust if you don't have one. We do handle UX/UI polish and component-level design as part of theme engineering.
How much does a typical project cost?
The discovery sprint is fixed-price and quoted up front. After that, most theme engineering projects run two to six 2-week sprints, while Hydrogen builds and Plus migrations are scoped individually. Every proposal lists scope, timeline, and price before you commit to anything.