Required add-ons for Shopify

Some add-ons aren't optional.

Make a companion product required — a warranty, an install kit, the laces a new pair of shoes needs — enforced from the product page all the way through checkout. It's a separate line at full price, never a bundle.

*Required add-on
Trail Runner Sneakers
$89.95
Add your shoelaces to check out.
Total $89.95
Shoelaces required — checkout blocked until added.
Required, not optional Never a bundle No discounts Separate line, full price Enforced at checkout No theme edits Works with Shop Pay Free to start
How it works

Three moving parts. You set one rule; the product page and checkout do the enforcing.

1

Build a requirement set

Pick a trigger product and the companion it can't ship without. Name it once — "Shoelaces required with running shoes" — and assign it to as many products as you like.

2

The product page enforces it

Shoppers see the required add-on right under the product, pick a variant, and watch the running total update. Add to cart stays locked until they choose — and express-checkout buttons are hidden so no one can skip it.

3

Checkout has the final say

A checkout rule blocks any cart that reaches checkout without the required companion — including Shop Pay, Apple Pay, and Google Pay. If the add-on is missing, the order can't complete.

What Reqmunk does

One job, done properly: make the add-on mandatory, everywhere it matters.

Gate the cart

Add to cart stays disabled until the shopper picks the required companion variant. No selection, no purchase.

Bypass-proof checkout

A Shopify checkout-validation function is the backstop — it blocks any cart missing the add-on, even Shop Pay, Apple Pay, and Google Pay express checkouts. Shoppers can't route around the requirement.

No theme edits

Turn it on with a one-click app embed. Add the checkout rule once in your settings. No code, no theme surgery.

Reusable requirement sets

Define a rule once, assign it to many products. Change the companion or the message in one place.

Not a bundle

The add-on is a separate line item at its own full price. No merged SKUs, no forced discounts, no repricing your catalog.

Shows the real total

The selector shows the companion's thumbnail, per-variant prices, and a running order total — so shoppers see exactly what they're buying before they add. No surprises at checkout.

Built for

If your product needs something to actually work, Reqmunk makes sure it's in the cart.

Extended warranties Protection plans Installation kits Laces for shoes Guards for skates Batteries for kits Assembly hardware Required service fees
Pricing

Free to start.

No per-order fees, no bundle math, no surprises.

Coming soon

More

Coming soon

More power for bigger catalogs.

  • Target whole collections, not just products
  • Multiple requirement sets
  • Custom "required selection" button label
Get notified
Questions

FAQ

No. Reqmunk installs as a one-click app embed — no theme code edits, no script injection. The checkout rule is added once in your Shopify checkout settings. Uninstalling leaves your theme exactly as it was.

No — it's the opposite. Reqmunk never merges products or changes prices. The required companion is added as its own separate line item at its own full price. It's a "non-bundling bundle": we require the add-on, we don't repackage or discount it.

Then the trigger product can't be bought until it's back — the same way Shopify treats any sold-out item. The product-page selector stays locked and checkout stays blocked. Reqmunk never quietly waives the requirement.

Yes. Express-checkout buttons are hidden on trigger products so shoppers can't skip the selector, and the checkout-validation function blocks any cart that reaches checkout without the add-on — including Shop Pay, Apple Pay, and Google Pay.

Every Shopify plan except Starter. Reqmunk's enforcement uses a checkout-validation function, which is available on Basic and up.

A requirement set can offer more than one companion product for the shopper to choose from, and the checkout rule enforces a 1:1 match — one required add-on for each trigger product in the cart.

Free to start — one requirement set with product triggers, the product-page gate, and the checkout rule. More capabilities, like collection targeting and multiple requirement sets, are coming.

Reqmunk is almost ready.

Drop your email and we'll tell you the day it's live on the Shopify App Store.