This project provides API for order management, using Elixir, GraphQL(Absinthe), PostgreSQL.

• Install docker and run docker-compose build
• Run docker-compose up
• Visit localhost:4040/api from your browser after building

Install Elixir, PostgreSQL and run mix test

• All mutations are atomic
• All IDs are UUIDs
• Query to fetch all orders
• Mutation to create an order
• Mutation to apply a payment to an order
• Mutation to order and pay in one go
• Subscriptions for all the above mutations

• Make mutations idempotent i.e if the payment is submitted twice, charge only once.
• Instead of preloading paymentsApplied, use Dataloader/Batching to load lazily.