The journey of every round

Define a DbContext with two entities (Order and Customer) related one-to-many. Show the OnModelCreating configuration and a simple query that loads orders with their customer.

Set up a RabbitMQ consumer that subscribes to an 'orders.created' queue. Show the publish call from the order service side.

Write a MediatR IRequestHandler<TRequest,TResponse> for a 'GetUserById' query, plus an IPipelineBehavior that writes the request type name to console before invoking the next handler.

Implement cache-aside using IDistributedCache backed by Redis to memoise an expensive lookup that returns a customer profile.

Write a BackgroundService that reads work items from an in-memory queue and processes each one with a small delay, with graceful shutdown handling.

Configure JwtBearer authentication so tokens are accepted from either the Authorization header or a query string parameter. Include the validation parameters.

Implement an IAuthorizationHandler for a 'CanEditOwn' permission that checks the current user owns the resource being modified.

Implement an IHealthCheck that returns Healthy when a TCP socket on a remote host responds within 500ms, and Unhealthy otherwise.

Create an ApiController class with a single GET ActionResult that returns a product or NotFound when no product matches the route id.

Write an IMiddleware implementation that adds an X-Request-ID header to every response. Show it being registered in the request pipeline.

Write a custom equality comparer (IEqualityComparer<Person>) that treats two Person records as equal when Email lowercased matches. Include GetHashCode.

Write a Regex that matches IPv4 addresses in the form '1.2.3.4' (each octet 0–255). Use Regex.Match on a sample string.

Write a ReadOnlySpan<byte>-based UTF-8 BOM check: return true if the span starts with the bytes 0xEF 0xBB 0xBF.

Write a using-block over a StreamReader that reads each line and counts occurrences of the word 'foo'. No async.

Write a generic Swap<T> method that swaps two ref T parameters. Include an example call with two ints.

Implement a multitenant request-scoped ITenantInfo resolver that reads the tenant id from a custom header and falls back to subdomain.

Build a SignalR Hub that lets clients subscribe to a 'price-tick' channel and broadcasts ticks to all subscribers on a one-second timer.

Implement a generic repository for read-only access to entities by id using a DbContext. Include AsNoTracking and a CancellationToken parameter.

Write a BackgroundService that reads work items from an in-memory queue and processes each one with a small delay, with graceful shutdown handling.

Write an IMiddleware implementation that adds an X-Request-ID header to every response. Show it being registered in the request pipeline.

The retailer is asking me to wait 4 weeks for a repair on a faulty appliance. Is that reasonable?

I bought clothing that didn't fit and the shop says they don't accept returns. Are my rights limited because it's a fitting issue?

A retailer is refusing to honour a price advertised on its website, claiming it was a mistake. Can I insist?

Goods I bought are not as described in the advertisement. What rights do I have?