Interview API

We would like you to design and build a fictitious refund API endpoint.

We have some existing code to help you get started, however feel free to change anything, design and build your solution as you would for a production environment.

Requirements

• A merchant must be enabled when creating a refund.
• A refund cannot be created when the card has expired.
• A refund must have a unique per merchant, merchant supplied reference.
• A refund can be standalone, created directly against a card.
• A refund against a purchase can be for a partial or full amount of the purchase.
• A refund must match the currency of the purchase.
• A standalone refund must match one of the allowed currencies for the merchant.

Guidelines

• Use Git and commit as often as you think is necessary to properly tell your story.
• Write tests using RSpec proving that your solution works.
• Use any tools, gems, patterns, etc that you would use in a production codebase.
• Engineer your solution as you would for a production environment.
• We are here to assist, feel free to ask questions.
• We want to see how you work, feel free to use your usual workflow including searching the internet, docs, AI, etc.

Getting started

1. Clone the repository.
2. Create a new branch to work from.
3. Run bin/setup.
4. Do your thing.
5. When you're done, push your branch and create a PR for review.