Thank you for taking the time to complete our coding test. Your challenge is to recreate a hypothetical version of our internal pricing service.

You can use any language, framework and/or library for this test. We want to see how you think about and solve problems in code, so make sure there is a decent chunk of your own code in there.

Feel free to spend as much or as little time as you'd like as long as the specified functionality is complete. As a ballpark, the test should take around 90 minutes of development time.

Using the pricing data, build a RESTful API endpoint that accepts requests like the one below.

{
    "order": {
        "id": 12345,
        "customer": {},
        "items": [
            {
                "product_id": 1,
                "quantity": 1
            },
            {
                "product_id": 2,
                "quantity": 5
            },
            {
                "product_id": 3,
                "quantity": 1
            }
        ]
    }
}

The endpoint should return a data structure which includes:

• the total price for the order
• the total VAT for the order
• the price and VAT for each item in the order

Data structure for the response is up to you.

All monetary values in the pricing.json file are in pennies (pound sterling, GBP). The calculated results should be in pennies too. Any rounding should use standard arithmetic rounding to the nearest penny.

In this hypothetical universe we have decided to launch tails.com overseas. We now want the pricing service to return prices in any currency. Those prices should be calculated using the latest available exchange rate.

Expand the API to allow a currency to be submitted as part of the request, and return the prices in that currency. How that currency code is passed in is up to you.

Use a currency conversion rate API like free.currencyconverterapi.com to get the latest exchange rates as part of your solution. (Hint: you might want to think about how to cache that data).

For the purposes of the test, assume the same VAT rates apply to all countries and currencies.

We would like to see some tests written in the testing framework of your choice for the pricing logic.

If you do not have time to write tests, tell us how you would test the pricing logic works as intended. For example: what level of testing, what sorts of test cases, etc.

Once you are happy with your code, zip it up and email it back to us along with answers to the following questions:

1. What command(s) do we run to install and start your server?
2. If you had more time, what improvements would you make if any?
3. What bits did you find the toughest? What bit are you most proud of? In both cases, why?
4. What one thing could we do to improve this test?