ASP.NET Core Web API Interview Question #180

How would you design an API for high traffic?

Senior API Design, Architecture, Scalability & Production Scenarios Senior Advanced

Quick Interview Answer

First measure the actual bottlenecks. Optimize database queries and indexes, paginate large results, reduce payload size, cache safe hot data, use asynchronous I/O, pool reusable resources, and scale application instances horizontally when appropriate.

Detailed Explanation

Protect expensive endpoints with limits and backpressure, monitor latency and saturation, and avoid assuming that adding more API servers will solve a database or downstream-service bottleneck.

Code Example

// Example read optimization:
var items = await _db.Products
    .AsNoTracking()
    .Where(x => x.IsPublished)
    .OrderBy(x => x.Id)
    .Take(50)
    .Select(x => new ProductDto(x.Id, x.Name))
    .ToListAsync(token);