[jstewartmobile]

In the modern context, engineering suggests a highly rigorous approach to design, testing, and implementation. This is typically only done for things where lives are at stake (civil, chemical, aerospace, etc.), or where a great inventories and reputations are at risk.

Very little software (even at Google/Apple/Facebook/etc.) is written to that standard -- regardless of how many "Software Engineers" they may employ -- because the cost of mistakes is still far less than the cost of adopting a more formal approach.

It's all about the process. Answering algorithms questions off the top of your head is neither here nor there.