A checkout that refuses to charge the wrong price

The call that places the order

The four things this checkout does that a buyer never sees and an operator depends on.

• Single-call, idempotent checkout

  POST /api/checkout/{code} takes the cart, contact, address, shipping rate and payment data, creates the order and returns what the client must do to pay. An Idempotency-Key retry resumes the same order instead of making a second.

  core/checkout.go

• No silent repricing

  A price that changed or stock that ran out returns 409 with per-line detail and the current values. The order is never charged at a figure the shopper did not see.

  core/checkout.go · LineConflict

• Guest checkout, for good

  An order needs an email, not an account; its access token is the guest’s handle. With the identity module a shopper can later claim a guest order into an account by presenting that token.

  core/orders.go · ext/identity

• Operator-placed orders

  Staff with orders.write place an order for a customer through the same checkout a shopper uses: the same stock reservation, numbering, discount checks and order.created event.

  POST /api/admin/orders

Payments

• Nine gateway modules

  Stripe, Razorpay, Adyen, Paddle, Lemon Squeezy, Creem, Hyperswitch, Helcim and RevenueCat, each configured from the admin’s payment methods screen.

  ext/payments-*/

• Cash on delivery by default

  The built-in cod method confirms the order and takes stock off the shelf at once; payment stays pending until an operator marks it paid.

  core/payments.go · codProvider

• Several gateways side by side

  Any number of providers run at once, each at its own checkout route with a webhook route the core owns. Writing your own is a two-method interface.

  core/ports.go · PaymentProvider

Customers and prices

• Order history for shoppers

  With the identity module, signed-in shoppers list and read their orders.

  ext/identity

• Address bookPartial

  Signed-in shoppers keep labelled addresses with a default. Missing: separate billing and shipping addresses, and staff editing a customer’s book.

  ext/identity

• Discount codesPartial

  Percentage, fixed or free shipping; scoped to the order, products, collections or a category; with minimum spend, dates, usage limits and once-per-email. Missing: automatic discounts at checkout, more than one code per cart, buy-X-get-Y.

  core/discounts.go

• Price listsPartial

  A line’s price resolves by customer group, channel, date window, priority and quantity break. Missing: a hook for your own pricing logic, and overriding one line’s price by hand.

  core/pricing.go

Stock, tax and shipping

• Stock reservationPartial

  Checkout reserves stock per location when the order is created and holds it until payment or until the unpaid-order window (24 hours by default) runs out. Missing: holding stock at the cart stage.

  core/inventory.go · reserveStock

• Shipping in partsPartial

  An order can ship in several parcels by line and quantity, each through any carrier module. Missing: several payments on one order.

  core/fulfillment.go

• Stock allocationPartial

  Each line is reserved at the first active location, by priority, that can cover it all. Missing: other strategies, and splitting one line across locations.

  core/inventory.go · pickLocation

• Tax ratesPartial

  Flat rates by country, state and category, the most specific winning, prices tax-inclusive or not, each line’s tax recorded. Missing: tax classes apart from categories, and per-channel rates.

  core/taxes.go

• Shipping zones and ratesPartial

  Zones by country and state, with named rates priced by basket subtotal (“free over 2,000”). Missing: weight-based rates and postal-code zones.

  core/shipping.go

• Address checksPartial

  Checkout requires line one, city, postal code and country. Missing: format rules and a validation hook.

  core/types.go · Address.Validate

Storefront

• A Svelte Commerce connectorPartial

  @misiki/gocommerce-connector 0.1.0, published on npm, covers catalogue, cart, shipping rates, checkout and order lookup. Missing: customer accounts and a search index.

  connectors/svelte-commerce

• Several carts at oncePartial

  Carts are anonymous tokens, so a client can hold any number. Missing: carts owned by a customer account.

  core/cart.go

Not in GoCommerce yet

Named here so nobody has to find out at launch. Each is absent from the code today.

• Recurring paymentsNo stored cards, subscriptions or off-session charges.
• Split paymentsAn order carries exactly one payment provider.
• Gift cards and store creditNo balance, issuing or redemption.
• Multi-currencyA store settles in one currency; channels carry none.
• Tax exemptionsNo exempt flag on customers, groups or orders.
• Tax or rate providersNo hook for Avalara-style tax or live carrier rates at checkout.
• Click-and-collectNo pickup option at checkout.
• Per-product quantity limitsA cart line is capped only by stock.
• ReorderNothing turns a past order into a new cart.