Interview questions

About these interview topics

These topics are practice for technical interviews, not for a certification exam. They cover the tools and ideas that come up in almost every backend, DevOps, platform and SRE interview: Linux, Git, Docker and system design.

Interviewers rarely ask you to recite a command or a definition. They describe something that went wrong and ask what you would do: a process that won't die, a commit that vanished after a reset, a container that ignores a stop signal, a service that falls over when one customer sends ten times the normal traffic. The questions here are written the same way, each one a short scenario with a single best answer and wrong options that sound plausible because they are what people actually try.

Who they help

• Candidates preparing for an interview loop, especially the troubleshooting or "walk me through it" rounds where you have to explain the why as well as the fix.
• Developers who learned these tools on the job by copying commands and want to fill the gaps before someone asks about them.
• People working towards a certification that assumes this ground. The Kubernetes exams expect you to be at home on a Linux node and to understand how container images are built, and the cloud architect exams test the same trade-offs as system design, with service names attached.

How to use them

Each topic has a 10-question test. Take one without preparing, then read every explanation, including those for questions you got right by guessing. The explanation of each wrong option is often the part worth knowing in an interview, because it is the follow-up question an interviewer asks next. Every question also has its own page with a link to the official documentation it is based on, such as the Linux man pages or the Git and Docker references.

A practical order is Linux, then Git, then Docker, since each builds on the one before. Leave system design until last: it assumes you are comfortable with how a single machine and a single service behave before you reason about many of them.

For the foundations underneath these topics, such as networking and operating systems, see the general IT group. Your scores are kept in your browser, and more tests will be added over time.