The complete guide: migrating your eCommerce to headless commerce

If your eCommerce platform feels like it's slowing you down more than moving you forward, you're not alone. Many companies in Mexico and LATAM run on monoliths that worked well five years ago, but today limit how fast they can iterate, how well they can scale during key campaigns, and their ability to deliver modern shopping experiences.

Headless commerce solves this by decoupling the frontend from the backend. In this guide, I'll walk you step by step through the migration process, including the mistakes we've seen (and made) across more than 38 modern architecture projects.

What is headless commerce?

In a headless system, the presentation layer (the "head" — your website, mobile app, kiosk) is separated from the commerce engine (catalog, cart, payments, inventory). The two layers communicate exclusively through APIs.

This means your frontend team can redesign the entire shopping experience without waiting for the backend team to ship a deploy. And vice versa: you can swap out your payment engine without touching a single line of the frontend.

5 signs you need to migrate to headless

• 1. Your time-to-market exceeds 3 months. If launching a landing page for a campaign takes weeks, your architecture is the bottleneck.
• 2. Your mobile conversion rate is stuck. Monoliths produce heavy frontends. Headless lets you build mobile-first experiences with frameworks like Next.js or Remix.
• 3. You can't integrate new tools easily. Want to add a PIM, a recommendation engine, or an AI chatbot? If every integration is a project of its own, your architecture needs to evolve.
• 4. You depend on a single vendor. If swapping any component means rewriting everything, you have vendor lock-in.
• 5. Your team spends more time maintaining than building. When 60%+ of your IT effort goes to maintenance, the opportunity cost is enormous.

The 5 steps to migrate to headless commerce

Step 1: Technical audit of your current stack

Before moving a single line of code, you need a complete map of what you have:

• Inventory of services, integrations, and dependencies.
• Identification of technical debt and legacy code.
• Mapping of critical business flows (checkout, inventory, pricing).
• Evaluation of existing APIs and their documentation.

We offer a free Health Check that covers the first three points. It's a good starting point before committing budget.

Step 2: Define the target architecture

With the diagnosis in hand, design the end state. Key decisions include:

• Commerce engine: Commercetools (pure enterprise), Shopify Plus (implementation speed), BigCommerce (cost-functionality balance).
• Frontend framework: Next.js (the industry standard), Remix, Hydrogen (if you choose Shopify), or a custom PWA.
• Infrastructure: AWS, Azure, or GCP. In most LATAM projects we use AWS for the maturity of the sa-east-1 and us-east-1 regions.
• Complementary services: headless CMS (Contentful, Sanity), search (Algolia, Elasticsearch), PIM (Akeneo, Salsify).

Step 3: Incremental migration with strangler fig

The strangler fig pattern is fundamental: instead of rewriting everything at once, you extract features from the monolith one by one and replace them with microservices. The monolith keeps running everything you haven't migrated yet. Recommended extraction order:

• 1. Frontend (lowest risk, highest visible impact).
• 2. Search and catalog.
• 3. Cart and checkout.
• 4. Order management and inventory.
• 5. CRM and external integrations.

Step 4: Testing and validation in parallel

Never shut down the old system until you've validated the new one 100%. Implement:

• Feature flags to enable/disable the new frontend by user segment.
• A/B testing between the legacy version and the new one.
• Monitoring of key metrics: conversion rate, load time, errors per minute.
• Load tests simulating your historical peak × 2.

Step 5: Cutover and ongoing operation

Switch day should be a non-event. If you did the previous steps well, the cutover is simply redirecting the DNS. After go-live:

• Keep the legacy system on standby for 30 days.
• Set up alerts and dashboards in Datadog or New Relic.
• Document runbooks for the most likely failure scenarios.
• Establish a continuous improvement cycle with 2-week sprints.

Common mistakes in headless migrations

Another frequent mistake is choosing the platform on price rather than technical fit. A cheap tool that doesn't adapt to your business flows ends up costing more in customizations and workarounds.

Recommended platforms for headless commerce

Frequently asked questions (FAQ)

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