Migrating from Nacelle to Swell - A Complete Guide

For merchants running Nacelle as their headless commerce integration layer, the multi-platform complexity eventually becomes a liability. Nacelle doesn't replace your commerce backend—it sits on top of Shopify, BigCommerce, or Salesforce, adding a GraphQL performance layer while you continue paying for the underlying platform, subscription apps, and CMS integrations separately. Headless commerce platforms built as complete commerce engines offer a different approach: one platform handling products, checkout, subscriptions, and customer data natively.

Swell addresses this architectural complexity by providing a unified API-first platform where the same Backend API powering the dashboard is available to developers for complete customization. The migration represents more than switching platforms—it consolidates your entire commerce stack into a single system.

Key Takeaways

• Nacelle migration to Swell isn't a like-for-like platform swap—you're consolidating multiple vendors (Shopify + Nacelle + subscription app + CMS) into a unified commerce engine, eliminating coordination overhead and reducing annual platform costs significantly
• The migration process follows strict data dependencies: products → customers → orders → shipments → subscriptions, with incorrect sequencing causing broken references and data integrity failures
• Swell's REST API architecture reduces the GraphQL expertise barrier that Nacelle requires, making development more accessible for general web development teams
• Native subscription billing eliminates third-party app dependencies and fees while providing tighter integration with checkout, payment tokens, and customer self-service
• Typical migration timeline runs 6-8 weeks—3-8 weeks faster than enterprise platform implementations—with pre-migration planning determining success more than store complexity

Understanding the Swell Advantage for Headless Commerce

The fundamental difference between Nacelle and Swell lies in what each platform actually provides. Understanding this distinction shapes every migration decision.

Why Swell Is an API-First Platform

Swell operates on a simple principle: the same API powering the admin dashboard and hosted checkout is available to developers. Every dashboard function—product management, order processing, customer accounts, subscription billing—works through the Backend API. This means developers can replicate, customize, or extend any native functionality without hitting artificial limitations.

The Backend API provides full CRUD access to all data models with secret key authentication. The Frontend API handles browser-based operations with public key authentication for customer-facing features. Both follow RESTful conventions, reducing the learning curve compared to Nacelle's GraphQL-only approach.

What "Headless" Means in This Context

Nacelle acts as "connective tissue" that collects data from your existing commerce platform, re-indexes it, and serves it through a GraphQL API optimized for Progressive Web App frontends. It enhances performance but doesn't replace your commerce backend.

Swell provides the complete commerce engine. Products, inventory, orders, customers, subscriptions, checkout, and payments all live in one system. You're not layering performance optimization on top of Shopify—you're replacing the entire commerce stack with an architecture designed for headless from the ground up.

Building Custom Experiences with Swell's APIs

Modern JavaScript frameworks connect directly to Swell's APIs. Build storefronts in React, Vue, Next.js, or Svelte. Deploy to Vercel, Netlify, or your own infrastructure. The headless storefront guide provides starter templates handling authentication, cart management, and checkout flows.

For merchants wanting faster launches, Swell's hosted storefront with visual theme editor offers drag-and-drop page building without custom development. The platform supports both paths without forcing either approach.

Seamless Transition: Migrating Your Store to Swell

Migration success depends on systematic preparation and understanding data relationships before moving anything.

Preparing Your Data for Migration

Nacelle doesn't store commerce data—it indexes and serves data from your underlying platform. Export from your source system (Shopify, BigCommerce) directly rather than from Nacelle itself.

Data inventory checklist:

• Products with all variants, options, pricing, and inventory levels
• Customer accounts with addresses, order history references, and custom fields
• Historical orders with complete line item, payment, and fulfillment details
• Active subscriptions including billing schedules, payment tokens, and next charge dates
• Custom metafields requiring mapping to Swell custom fields

Review products approaching or exceeding your current platform's variant limits. These items benefit most from Swell's unlimited variant capability and need restructuring during migration.

Leveraging Swell's APIs for Data Import

The migration endpoint with $migrate: true flag enables bulk imports while preserving original IDs and skipping validation for historical data. Follow the dependency sequence strictly:

1. Products first (no dependencies)
2. Customers second (no dependencies)
3. Orders third (require product_id and customer_id)
4. Shipments fourth (require order_id)
5. Subscriptions last (require everything above plus payment tokens)

Batch imports handle up to 1,000 records per call. For catalogs under 10,000 products, expect 2-3 weeks for data migration. Larger catalogs (50,000+ products) require 8+ weeks.

Critical warning: Do NOT use $migrate: true for subscriptions. They rely on subsequent events to set up billing automation properly. Skipping event triggers breaks automatic payment processing.

Testing Your Swell Store Pre-Launch

Swell provides test environments separate from live stores. Validate data accuracy across representative samples:

• Verify variant combinations, pricing, and inventory counts
• Confirm customer accounts, addresses, and customer group assignments transferred correctly
• Check order totals calculate accurately with product references resolving properly
• Test subscription billing schedules and payment method attachment

Run both systems in parallel for 2-4 weeks before full cutover. This validation period catches issues before they impact customers.

Swell vs. Nacelle: Unlocking Unlimited Potential

The feature comparison reveals why merchants consolidate from multi-platform Nacelle stacks to unified Swell architecture.

Beyond Platform Limitations with Swell

Nacelle's capabilities depend entirely on your underlying commerce platform. If Shopify limits you to 100 variants, Nacelle can't bypass that restriction—it's just indexing what Shopify provides.

Swell removes these constraints entirely. Unlimited variants, options, and custom attributes work across all data models. A product can have unlimited size/color/style/material combinations with custom text fields, measurement inputs, and product-specific metadata. The model editor enables creating entirely custom data structures for business-specific requirements.

Financial Benefits: Transaction Fees and Simplified Billing

Nacelle's custom enterprise pricing typically starts at several thousand dollars monthly—on top of your Shopify Plus, BigCommerce, or Salesforce Commerce Cloud subscription. Add subscription app fees and you're coordinating multiple vendor invoices monthly.

Swell's transparent pricing scales with business size through defined tiers. The competitive transaction fee structure on external payment gateways, combined with eliminated third-party app subscriptions, delivers meaningful cost reduction for growing businesses.

Developer Empowerment: REST vs. GraphQL

Nacelle requires GraphQL expertise—a specialized skill set not every development team possesses. While GraphQL offers flexibility, the learning curve adds project time and limits your developer hiring pool.

Swell's RESTful APIs follow patterns most web developers already understand. The developer console built into the dashboard lets you test API calls, view request/response logs, and troubleshoot without additional tooling. Teams can start building faster without specialized GraphQL training.

Subscription & Sales Models: Powering Your Business with Swell

Native subscription billing represents one of the largest cost savings when migrating from Nacelle-based architectures.

Building Resilient Subscription Services

Nacelle setups typically require ReCharge, Bold Subscriptions, or similar third-party apps—adding monthly fees and creating integration complexity between checkout, subscription management, and your underlying platform.

Swell's subscription engine works natively with the encrypted card vault. Define billing intervals (monthly, yearly, custom), separate invoicing from fulfillment schedules, and configure automatic dunning rules for failed payments. Customer self-service handles pause/resume, payment updates, and plan changes without support tickets.

Flexible Selling: One-Time, Subscription, and Mixed Models

Purchase options let you sell the same product as a one-time purchase or subscription with different pricing—customers choose at checkout rather than browsing separate product listings.

Mixed cart functionality combines subscription and one-time products in single transactions. A customer can subscribe to monthly coffee delivery while adding a one-time grinder purchase in the same checkout, with Swell handling both order types seamlessly.

Scaling with Marketplace Features

For multi-vendor marketplace models, split payment functionality distributes funds to vendors automatically. Product bundling with individual inventory tracking supports complex selling strategies without third-party apps.

Maximizing Your Store's Reach with Swell's International Features

Global expansion requires proper currency handling, localized content, and automated tax compliance—features that add complexity to multi-platform Nacelle stacks but work natively in Swell.

Implementing Global Currency and Pricing Strategies

Swell supports 230 currencies with two approaches: explicit pricing rules per currency for psychological pricing strategies, or automatic exchange rate conversion for simplified management.

Configure product prices, shipping costs, and discount amounts per currency through the dashboard or API. Geolocation suggests currencies based on customer location, with manual override available.

Localizing Content for Diverse Audiences

Multi-language support across 170 languages handles field-level translation for all customer-facing content: products, categories, checkout instructions, and email notifications. Translations happen through the dashboard or API, enabling integration with professional translation services.

Streamlining International Tax Compliance

Avalara AvaTax and TaxJar integrations automate tax calculation based on customer location, product type, and applicable rules. Create custom tax rules by location and product type for specific compliance requirements.

Development Workflow & Support on Swell

The development experience determines how quickly teams can build and iterate on commerce experiences.

Accessing Swell's Developer Resources

The developer documentation provides API references, integration guides, and framework-specific tutorials for Next.js, React, and Vue implementations. The help center covers dashboard operations, integration setup, and troubleshooting.

Webhook support enables real-time event notifications for custom business logic. Subscribe to specific events (order placed, subscription renewed, payment failed) and Swell POSTs complete object data to your endpoints immediately.

Leveraging the Partner Network

The agency partner program connects merchants with development shops experienced in Swell implementations. For complex migrations or custom storefront builds, certified partners accelerate timelines while reducing risk.

FlexiPort integration uses AI-powered field mapping to complete platform migrations in as little as one business day for straightforward catalogs.

Understanding Support Tiers

Email and chat support comes standard across all plans. Priority support activates at higher tiers. Developer support providing direct technical assistance for complex implementation needs is available on enterprise-level plans.

Cost-Benefit Analysis: Swell's Pricing and Value

Understanding true platform costs requires looking beyond monthly subscriptions to total cost of ownership.

Comparing Swell's Tiers to Your Business Needs

Swell's pricing structure scales with business size through defined tiers. Key differentiators include admin user limits, monthly API request allocations, data storage, reporting capabilities, and support levels. Higher tiers add features like international price lists and role-based permissions.

Annual billing provides meaningful discounts compared to monthly subscriptions. Revenue-based fees apply when sales exceed plan thresholds, with higher plans offering more favorable overage rates.

Calculating Potential Savings

Nacelle-based architectures typically involve:

• Underlying commerce platform fees (Shopify Plus, BigCommerce Enterprise, etc.)
• Nacelle integration layer costs
• Third-party subscription app fees
• CMS integration costs
• Additional apps for features native to Swell

Consolidating to Swell eliminates multi-vendor coordination while providing native subscriptions, unlimited product modeling, customer group pricing, and flexible checkout—all included rather than purchased separately.

Understanding Scalability Without Re-platforming

Businesses can start on entry-level plans and scale through higher tiers as revenue grows. The platform handles hundreds of companies globally with 99.963% uptime. Infrastructure combines bare metal servers and cloud providers to handle traffic spikes during promotional periods.

Practical Features for Your E-commerce Success on Swell

Day-to-day operations benefit from features that often require third-party apps on other platforms.

Optimizing Product Catalogs

Unlimited products and variants with custom attributes visible or hidden from customers. Product types span physical goods, digital downloads, services, bundles, and gift cards. Unlimited categories and sub-categories with drag-and-drop organization. CSV import/export for bulk product management.

Enhancing Checkout Experiences

Hosted Swell Checkout handles PCI compliance while offering customization through settings. Custom checkout via API enables complete control for businesses with specific requirements.

Abandoned cart recovery emails with automated sequences recapture lost sales. Guest checkout reduces friction for first-time buyers. Saved payment methods in the encrypted vault enable faster repeat purchases.

Streamlining Fulfillment Operations

Multi-warehouse management with flexible shipping rules by geographic zone, service type, or price point. Product-specific shipping handles items requiring special handling. Split fulfillment ships order items separately when needed.

Future-Proofing Your Business: Swell's Scalability and Innovation

Migration decisions should account for where your business will be in 3-5 years, not just current requirements.

Investor Support and Industry Leadership

Backing from VMG Catalyst, Headline, Bonfire Ventures, and Commerce Ventures provides growth capital. Notable angel investors include Guillermo Rauch (Vercel founder/CEO), Jason Warner (former GitHub CTO), and Mark Lenhard (former Magento and PayPal executive)—industry leaders validating the platform's technical approach.

Extending Capabilities with Custom Apps

The custom Swell Apps framework enables building full-stack extensions on the platform. For business-specific requirements not covered by native features or integrations, custom apps provide extension points without forking core functionality.

Frequently Asked Questions

Can I reuse my Nacelle PWA frontend components with Swell?

Not directly—Nacelle's GraphQL queries don't translate to Swell's REST API patterns. However, the frontend component logic (React/Vue components, styling, user experience flows) can inform your Swell storefront build. Many teams rebuild frontends using Swell's starter templates as a foundation, incorporating design elements from their Nacelle implementation. The rebuild provides an opportunity to optimize for Swell's data structures rather than working around Nacelle's limitations.

What happens to my CMS integrations during migration?

Swell integrates natively with Contentful and supports other headless CMS platforms through API connections. If you're using Contentful with Nacelle, the integration can continue with Swell—your content remains in Contentful while Swell handles commerce. For other CMS platforms, evaluate whether native Swell content management covers your needs or if maintaining separate CMS integration adds value.

How do I handle the GraphQL to REST API transition for my development team?

REST API patterns are more accessible for general web developers without specialized GraphQL training. Swell's Node.js SDK abstracts many API interactions, reducing direct REST call complexity. Most teams report faster onboarding to Swell's REST architecture compared to maintaining GraphQL expertise required for Nacelle development.

What's the risk of subscription billing disruption during migration?

This represents the highest-risk migration element. Extract payment tokens from Stripe or Braintree BEFORE starting migration. Import customers and products first, then create subscription records referencing existing payment tokens. Set date_trial_end to align with original next billing dates. Test billing in Swell's test environment before production migration. Never use the migration flag that skips validation for subscription records—they need proper event triggers to establish billing automation.

Does Swell support the same PWA performance benefits that Nacelle provides?

Yes, through different architecture. Nacelle optimizes performance by re-indexing your existing platform's data for faster API responses. Swell's Frontend API provides similar performance characteristics natively, with media delivery through global CDN and image transformation capabilities. Custom headless storefronts deployed to Vercel or Netlify can achieve equivalent or better performance than Nacelle PWA implementations while eliminating the multi-platform complexity.