Most "Shopware vs Shopify" posts compare dashboards, app stores, and pricing tables. None of that matters to you until the day a client asks for something the platform won't let you build. Then the comparison stops being a feature grid and becomes a question about ceilings: how high can I go before the platform says no, and what happens when I hit it?

That's the only axis I care about as a developer, so that's the one I'll argue on. Shopify is an outstanding product. It's also a closed SaaS that decides, on your behalf, where customization ends. Shopware is open source built on Symfony, which means the ceiling is "however far PHP and HTTP will take you." Below are the three places that difference actually bites, with code.

Angle 1: The checkout is the wall

This is the headline because it's where most agency developers first hit something they cannot do.

For years the Shopify answer to "customize the checkout" was checkout.liquid. That era is over. Shopify deprecated checkout.liquid in favour of Checkout Extensibility. Plus stores had to migrate their Thank-you and Order-status pages by August 28, 2025, and in January 2026 Shopify began auto-upgrading stores — wiping customizations built on additional scripts, script-tag apps, or checkout.liquid. Non-Plus stores have until August 26, 2026, and legacy Shopify Scripts keep working only until June 30, 2026. (Shopify migration timeline)