Most merchants treat "limit how much customers can order" and "let customers choose a delivery date" as two separate jobs, handled by two separate apps. They're not two jobs. They're the same job — matching demand to what you can actually fulfill — seen from two sides. This post explains why they belong in one app, and how merchants use both together.
One idea: rules on orders
Every capacity problem is a rule on an order. Don't take more than 50 orders today. Don't sell after 6pm. Don't let one customer buy 200 units. Don't accept a delivery for a day we're closed. Same shape, same enforcement point: the checkout.
OrderRules started on one side of that idea — when a customer can order:
- Automated store hours and holiday closures
- Daily, weekly, and monthly order caps
- Per-customer and per-product purchase limits
- Step / increment quantity rules
- All enforced server-side with Shopify Functions, so Shop Pay and express checkouts can't bypass them
Delivery Dates is the mirror image — when you can deliver:
- A delivery date & time-slot picker on product and cart pages
- Capacity limits per date and per slot
- Blackout dates and holiday-aware estimates
- Scheduled in-store pickup across locations
- Japanese carrier CSV export (Yamato, Sagawa, Japan Post)
Same merchant, same mental model, same technical surface.
Why one app beats two
Stitching two apps together looks fine until the rules interact — which they always do.
- One enforcement layer, no conflicts. When order caps and delivery rules live in one Function, they reason about the same order together. Two apps each running their own checkout validation is where mysterious "why was this order blocked?" bugs come from.
- Rules that reference each other. A same-day cutoff only makes sense against your store hours. A delivery blackout should reuse the store holidays you already set. In one app, they share that calendar; across two, you maintain it twice.
- One config, one place to look. Your Saturday capacity is a single number, not one cap in app A and a slot limit in app B that quietly disagree.
- One subscription, one support thread. Two apps mean two bills, two dashboards, and two vendors pointing at each other when something breaks.
How merchants use both together
A bakery caps Saturdays at 50 orders and offers a delivery-date picker with per-day slots. The cap and the slots are the same capacity expressed two ways — the picker stops the 51st order from ever choosing Saturday.
A florist runs a 2pm same-day cutoff (an order rule) alongside per-delivery-date caps (a delivery rule), so Valentine's Day fills to its real route capacity and then rolls to the next open day automatically.
A Japanese store pairs 注文制限 (order limits) with 配送日時指定 (delivery date/time selection) and hands the day's shipments to Yamato or Sagawa as a carrier CSV — order control, delivery control, and fulfillment in one place.
The Japan angle
Japan is where the two halves come together most clearly. Slot-at-checkout is a consumer default, carrier CSV export is table stakes for operations, and no global app bundles order limits and delivery scheduling and Japanese carrier CSV in one product. OrderRules does — which is why the launch leads with Japan while working everywhere.
Where to start
If you already use OrderRules for order limits, delivery scheduling is a switch you turn on, not a second app to evaluate. If you're new, you can adopt either side first and grow into the other.
- Delivery date picker · In-store pickup · Carrier CSV export
- All features · Pricing
- Guide: How to add a delivery date picker to Shopify
Control when customers order — and when you deliver — in one app. Start a free 14-day trial.