Explore Alexandria · Optio Alexandria

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Illustrative payment system · authored sample knowledge

What does the recorded payment tell us?

Inspect Payment and its confirmation records. The authored source explains when the outcome becomes known and how duplicate deliveries are recognized.

Read the data, its ownership and the evidence behind the picture.

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Pay for the €100 lamp

Illustrative system · authored sample records. Mira buys a EUR 100.00 lamp, order ord-1042. Payment pay-1001 initially has an unknown outcome after checkout times out.

Actor: Mira · customer
Goal: Pay once and understand whether the shop can fulfil the order.
Trigger: Mira chooses Pay for the €100 lamp.
Outcome: Processor-confirmed payment lets the shop fulfil the order. Unknown and confirmed-decline outcomes remain visibly different.

Next step 3 steps

Preconditions

The fictional order ord-1042 requests EUR 10000. No real account, card, payment or provider credentials exist.

Steps

1 Mira chooses Pay for the €100 lamp. · Buy the €100 lamp
2 The service records, submits and resolves one logical payment. · Request one logical payment, Read and record payment state, Submit the same payment operation, Receive payment confirmation, Apply a compatible outcome
3 Checkout reads what is known; a missing answer remains visibly unknown. · Read the recorded answer, Check the existing operation, Read and record payment state

Failures and retries

No checkout response within 10 seconds: keep pay-1001 confirming and seek the existing operation’s outcome.
A confirmed decline is an explicit failure; a separate new attempt can then be requested.

Acceptance criteria

Fulfil only after processor-confirmed payment; preserve the same logical operation when its outcome is unanswered.
Repeated delivery of evt-9001 leaves one recorded EUR 10000 payment; ordering and exactly-once delivery are not assumed.

Open questions

Who owns a payment that remains unresolved? See dec-unresolved-payment-escalation.

Flows

Resolve one payment without inventing its outcome · Step 2