Medusa Project Structure: Where Every Kind of Code Belongs
Medusa loads code by convention. A directory-by-directory guide to what goes where, and the decision tree for placing any new piece of logic.
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Field notes — page 4
Payment Providers in Medusa: Architecture, Choice and Failover
How Medusa's payment abstraction works, why running two providers is easier than you think, and the authorise-versus-capture decision that determines your refund story.
Implementing a Medusa Cart That Does Not Lose Items
Cart persistence, the guest-to-customer merge, inventory races and optimistic UI. The cart problems that only appear in production, and how to avoid them.
Block-based pages, two years in
What works, what we changed, and what we would never do again.
Customising the Medusa Admin: Widgets, Routes and UI Extensions
The dashboard is a React app you can extend. Injecting widgets into existing pages, adding new routes, and the conventions that keep extensions from looking bolted on.
Medusa vs Shopify: An Honest Comparison for 2026
Not a feature grid written by someone selling one of them. Where Shopify genuinely wins, where Medusa does, and the revenue point where the maths flips.
Medusa Events and Subscribers: Reacting Without Coupling
How Medusa's event bus works, when a subscriber is the right tool instead of a workflow step, and the retry semantics you need to design around.
Medusa Plugins: Building and Publishing Reusable Commerce Packages
When a module should become a plugin, how the package is structured, and what changes when your code has to run in someone else's application.
The Medusa JS SDK: Querying, Auth and the fields Parameter
The SDK is thin on purpose. What it handles, how authentication differs between store and admin, and why the fields parameter is the difference between a fast storefront and a slow one.
Shopify to Medusa Migration: The Complete Technical Guide
Catalog, customers, orders, subscriptions and the redirect map that decides whether you keep your rankings. A working plan for moving off Shopify, from people who have done it.
The Medusa Container: Dependency Injection Without the Ceremony
Everything in Medusa is resolved from a container. What is registered, how scoping works per request, and how to avoid the two mistakes that cause leaks.
Design tokens, not themes
A small rant about why "dark mode toggle" is the wrong abstraction.