Can you explain the Builder pattern with a real-world .NET example?

Short answer: Builder separates complex object construction from its representation. For example, building an HttpRequest with optional headers, query params, and body: public class HttpRequestBuilder

Example code

{
private HttpRequestMessage _request = new HttpRequestMessage();
public HttpRequestBuilder SetMethod(HttpMethod method)
{
_request.Method = method;
return this;
}
public HttpRequestBuilder AddHeader(string key, string value)
{ _request.Headers.Add(key, value); return this;
}
public HttpRequestMessage Build() => _request;
} Allows building requests step-by-step fluently.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.