Checkout

What it does: Guides the customer from cart to placed order — collecting delivery details, validating everything, and submitting the order intent.

Why it matters: Checkout is the highest-stakes step. Any failure here means a lost sale. Checkout must handle guest users, delivery vs. collection differences, and be resilient to submission errors.

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Feature Table

Feature	Problem It Solves	What It Does	How It Works	Dependencies	Prerequisites	Limitations	Impacted Metrics
Guest Checkout	Not every customer wants to create an account	Lets customers place an order without signing in	Session-based checkout: OTP email or anonymous session used; cart tied to session	Checkout Orchestrator, Address service	Valid cart with items	No order history or loyalty for guest sessions; addresses not saved	Guest checkout conversion rate
Checkout — Delivery	Customer wants food delivered to their address	Collects delivery address, shows fees, submits order	Address validated → delivery fees quoted → order submitted with delivery info attached	Checkout Orchestrator, Address service, Geo service	Delivery mode set; store with delivery coverage active	Address must be within coverage zone; fees are backend-calculated (not Byte Helium-owned)	Delivery checkout rate
Checkout — Collection	Customer picking up in store	Simplified checkout with store selection and pickup time	Store confirmed → no address needed → order submitted	Checkout Orchestrator	Collection mode set; store open	Store must be in open state; throttling policies may limit orders	Collection checkout rate
Checkout Delivery Variants	Different markets/scenarios have different checkout flows	Supports market-specific checkout step configurations	Orchestrator manages variant-aware checkout sessions; steps vary by context	Checkout Orchestrator	Market variant configured	Variants must be configured by the market team — not self-serve from Byte Helium	Checkout completion rate by variant
Order Again	Customer wants to repeat a previous order	Repopulates cart with items from a past order	Previous order detail fetched → items added back to cart → checkout resumed	Orders service, Cart Service	Customer must be signed in; previous orders must exist	Items unavailable in current menu will be excluded with a warning	Reorder rate

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Technical Sources

📎 Technical Source: Guest Checkout / Delivery Checkout

• FRD References: FRD-HEL-012, FRD-HEL-013, FRD-HEL-014, FRD-HEL-015
• TRD Domain: Checkout (Core)
• Key Interfaces / APIs: Start/Resume Checkout, Address Create/Validate, Fees & Taxes Quote, Submit Order
• Data Contracts: CheckoutSession (id, cartRef, mode, steps); OrderIntent (totals, tenders, deliveryInfo — with idempotency keys)
• Source Summary:
  • Checkout submission p99: ≥99.5% success
  • Idempotency keys prevent duplicate orders on resubmit (409 replay returns original orderRef)
  • Fees and taxes calculated by backend — Byte Helium displays only
  • Orchestrator APIs: additive changes only, 120-day deprecation
  • Correlation IDs tracked for all submission events

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See it in the wiki

• How customers experience checkout in the front-end → Order and Get: Checkout