Understand the distinction: a fixed bundle has a predetermined set of components and variants chosen by the merchant; a componentized bundle allows buyers to select among variant options within each component slot.
For fixed bundles, all component variants are specified at bundle creation time and cannot be changed by the buyer at checkout.
For componentized bundles, use the bundle components structure that exposes options (e.g., size or color) per component slot, allowing buyer selection via a bundle UI extension at checkout.
Implement a Checkout UI Extension to render component selection UI for componentized bundles if buyer customization is required.
Ensure checkout validation and line item attributes correctly capture buyer selections for componentized bundles so fulfillment knows which specific variants to pick.
Consult current Shopify Bundles documentation for which bundle type is natively supported by the Bundles API vs which requires custom app logic.
Known gotchas
Componentized bundles typically require a Checkout UI Extension to render the selection interface; this adds app development complexity beyond just creating the bundle product.
Bundle pricing strategies (sum of components, fixed bundle price, or discount) vary by implementation; ensure the bundle price is explicitly set and does not inadvertently expose component pricing that confuses buyers.
Give your agent this knowledge — and 200+ more routes
One MCP install gives any agent live access to the full route map, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp