Sam Thompson

Available for freelance and contract work

Sam Thompson Senior Shopify Developer Custom Apps, Subscriptions and AWS

I build whole systems for Shopify brands, not just themes.

Custom apps, subscriptions that don't break, and the AWS infrastructure behind them, backed by nearly 20 years of commercial experience.

Get in touch LinkedIn (opens in a new tab)
Hand-drawn sketch of how a typical custom Shopify app runs on AWS. The Shopify store sends webhooks to Amazon EventBridge, which feeds an SQS queue. A Lambda worker processes the queue, keeps state in DynamoDB, and writes configuration back to the store through Admin GraphQL API mutations as metafields. Shopify Functions read those metafields inside checkout. The merchant uses an embedded Polaris app UI in the Shopify admin, which fetches from an API Lambda through CloudFront, backed by DynamoDB for sessions and app data. EventBridge Scheduler triggers the worker on a cron schedule.

About

I build whole systems for Shopify and Shopify Plus brands, not just themes: custom apps, subscriptions that don't break (Recharge, Ordergroove and Skio), and the AWS infrastructure behind them.

I'm a senior developer with nearly 20 years of commercial experience across digital agencies and freelance work. I'm happiest owning the tricky problems, and I see projects through from first scoping to post-launch fixes and ongoing development.

I'm based in North Wales, UK, and work remotely.

Selected work

A few recent projects from my work at Underexposed. Client names are left out on purpose.

WooCommerce → headless Shopify

Custom discounts for a bed retailer

I helped a bed retailer move from WooCommerce to headless Shopify by building a custom discounts app for bundles, BOGO, mix-and-match and complex client-specific rules beyond Shopify's native capabilities.

It runs on AWS Lambda with SQS queues and scheduled jobs, CloudFront and S3, all deployed through a Git-based workflow. I also built a sync app that lets their development stores pull data from production, so the team can test against real data.

  • Headless Shopify
  • Custom app
  • AWS Lambda
  • SQS
  • Scheduled jobs
  • CloudFront
  • S3
  • Git-based deploys

Subscription migration

250,000 customers, moved safely

I've led large Recharge and Ordergroove migrations, including one covering 250,000 customers, moving subscriptions and customer accounts across with careful testing and reconciliation.

  • Recharge
  • Ordergroove
  • Subscriptions
  • Customer accounts
  • Testing
  • Reconciliation

Public Shopify app

A customisable shopping cart app

A customisable shopping cart app, launched on the Shopify App Store as a public app for merchants to install.

  • Shopify App Store
  • Public app
  • Cart

Also

  • Multi-market Shopify launches across the UK, EU, Ireland, Australia and the US
  • Consultation and prescription flows for a UK health platform
  • A Laravel CMS for a creative-industry portfolio platform
  • Custom Shopify apps from reviews, analytics, promotions and bundles to checkout extensions and subscriber account tools for pausing, swapping and skipping orders

Skills

The tools I use day to day.

Frontend

  • JavaScript
  • TypeScript
  • Vue.js
  • React
  • Next.js
  • Remix
  • Alpine.js
  • Tailwind
  • Vite
  • Polaris
  • HTML
  • CSS
  • Responsive UI
  • Shopify themes
  • Liquid

Backend

  • PHP
  • Laravel
  • Node.js
  • REST APIs
  • GraphQL APIs
  • Shopify Admin API
  • Shopify Storefront API
  • Webhooks
  • Queues
  • SQL
  • DynamoDB

Commerce

  • Shopify
  • Shopify Plus
  • Headless Shopify
  • Hydrogen
  • Custom and public Shopify apps
  • Shopify Functions
  • Checkout UI extensions
  • Customer Account UI extensions
  • Shopify Flow
  • Shopify Markets
  • Recharge
  • Ordergroove
  • Skio
  • Klaviyo

DevOps

  • AWS Lambda
  • ECS
  • SQS
  • EventBridge
  • CloudFront
  • S3
  • SES
  • CloudWatch
  • SST
  • Terraform
  • Docker
  • Vercel
  • Cloudflare
  • Sentry
  • CI/CD
  • GitHub workflows

AI

  • Claude
  • Cursor
  • AI-assisted development
  • Code review
  • AI features in Shopify apps

Experience

Nearly 20 years across digital agencies and freelance work.

  1. Underexposed · Senior Web Developer

    09/2018 – Present · Remote

    I build and look after high-traffic ecommerce and subscription platforms for clients in health and beauty, subscription retail, consumer products and digital publishing, much of it through custom Shopify apps.

  2. Lean Labs · Freelance Web Developer

    10/2014 – 12/2017 · Remote

    Full-stack websites from design to browser on HubSpot and WordPress, in a fully remote team (from Costa Rica to the Philippines!).

  3. Shout! Creative · Freelance Web Developer

    02/2011 – 10/2014 · Norwich

    As Shout!'s only web developer, I took every project from start to finish, building custom WordPress templates.

  4. One Agency · Freelance Web Developer

    10/2008 – 01/2012 · Norwich

    Maintained and developed a large electronics retailer's white-label ecommerce sites and backend EPOS integration, then delivered ecommerce projects for large clients.

Education

BSc (Hons) Computing Sciences, University of East Anglia, 2004 – 2007

Available for freelance and contract work

Got a Shopify build, custom app or subscription migration in mind? Send me a message using the form and I'll get back to you, or get in touch on LinkedIn.

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