URL Shortener Coding Task

Task

Build a simple URL shortener in a ** preferably JVM-based language** (e.g. Java, Kotlin).

It should:

• Accept a full URL and return a shortened URL.
• Persist the shortened URLs across restarts.
• Allow a user to customise the shortened URL (e.g. user provides my-custom-alias instead of a random string).
• Expose a decoupled web frontend built with a modern framework (e.g., React, Next.js, Vue.js, Angular, Flask with templates). This can be lightweight form/output just to demonstrate interaction with the API. Feel free to use UI frameworks like Bootstrap, Material-UI, Tailwind CSS, GOV.UK design system, etc. to speed up development.
• Expose a RESTful API to perform create/read/delete operations on URLs.
  → Refer to the provided openapi.yaml for API structure and expected behaviour.
• Include the ability to delete a shortened URL via the API.
• Have tests.
• Be containerised (e.g. Docker).
• Include instructions for running locally.

Rules

• Fork the repository and work in your fork. Do not push directly to the main repository.
• We suggest spending no longer than 6-8 hours, but you can take longer if needed.
• Commit often with meaningful messages.
• Write tests.
• Use the provided openapi.yaml as a reference.
• Focus on clean, maintainable code.
• AI tools (e.g., GitHub Copilot, ChatGPT) are allowed, but please do not copy-paste large chunks of code. Use them as assistants, not as a replacement for your own work. We will be asking.

Deliverables

• Working code.
• Decoupled web frontend (using a modern framework like React, Next.js, Vue.js, Angular, or Flask with templates).
• RESTful API matching the OpenAPI spec.
• Tests.
• A git commit history that shows your thought process.
• Dockerfile.
• README with:
  • How to build and run locally.
  • Example usage (frontend and API).
  • Any notes or assumptions.