How to build Custom Bundles / Bundle Builder?

Bundle Builder gives your customers the option of choosing from a selection of products (curated by you) to create their desired bundle. It is a 2 step process, in the 1st step you create your parent bundle product in shopify admin, in the next step you add bundle definitions (it's components) for each product variant.

Follow these steps to create a bundle builder

Step 1: Create the product in Shopify

On the Shopify Product page, go to the Options section and select "This product has options, like size or color". Here, you can add in the options that your customers can select from. For example.

As you can see, We have created 2 options here for our customers to choose from

Option 1 allows selection of perfumes for the gift set, it has 3 values
Option 2 is for selection for body oils, it has 2 values

In total we will have 3x2 = 6 Variants here in this product.

Please Note: Currently Shopify enforces a hard limit of 100 variants per products and maximum 3 set of options (dropdowns on storefront) limit per product, but it is rumored that soon (before Winters 23 Editions) this limits is going to be removed.

Step 2: Build the Bundle

Next part is similar to building a regular bundle in profit bundles.

Open the app, Go to the bundles tab. Click on Add New Bundle, it should open the bundle creation flow with 2 steps. In the 1st step, select the parent bundle product(s). So here select the product you just created with all it's 6 variants.
Next in the second step, add individual SKU for each product variant of the bundle. Add the composition (child skus) and properties like price and weight for each bundle variant.
Click Save. This will create 6 separate bundles in app (1 for each product variant).

Now when customer purchases any bundle variant after customizations, app shall add these bundle components as per composition rules defined by you.

P.S. It is totally possible to create bundle builder where not all components are available for option selection i.e they are part of bundle composition but not available for choice selection for customers. You would need to add these as part of your composition definition during creation process.

Advantages of this approach

There are many bundle builder apps in Shopify app store. But in order to create a bundle builder for your store, they mess with your theme code. Which can lead to many complications like degraded store performances and inconsistent branding.
In this approach your bundle builder page is totally in your own control. Your theme stays consistent.
You create this bundle once and you sell it everywhere like your normal Shopify products, which is not possible if you have an bundle builder app that creates custom storefront flow .
It could be included in your upsell funnel apps like cart upsell or post purchase upsell.
They are compatible with translations apps and Shopify Markets.