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The Trade-offs Every Engineer Should Know Before Their Next Whiteboard Interview

System Design on AWS: The Trade-offs Every Engineer Should Know Before Their Next Whiteboard Interview

Build a RESTful Web Service with Spring Boot, Gradle, and OpenAPI

By the end of this guide you’ll have a working Spring Boot RESTful API, built with Gradle and documented with OpenAPI, and a live Swagger UI page you can show...

Items in Containers: Count Items in Closed Compartments (Code Interview Problem)

This one shows up in online coding assessments under the name Items in Containers, and it’s a trap: the obvious solution passes the examples and then times out on the...

From O(n²) to O(n): Replace Nested Loops with a HashMap in Java

One endpoint in a B2B order system I worked on returned 1,000 orders, and it was slow. The database wasn’t the problem. Two innocent-looking nested loops were. Here’s how one...

Swagger Codegen: Moving from design to API development

Swagger Codegen can simplify your build process by generating server stubs and client SDKs for any API, defined with the OpenAPI.

Shopping options with a limited budget

A shopper wants to buy one item from each category: pants, sneakers, a skirt, and a t-shirt. Each category has multiple price options, and the shopper must stay within a...