Senior IT Interview Guide: System Design, Leadership and Behavioural Questions

The short version

Senior interviews test judgement. Interviewers already assume you can code. They want to see how you decide, how you handle ambiguity and how you lead.

Typical rounds

1. Recruiter call: background, expectations, notice period and compensation range.
2. Technical depth: your main technology and past projects.
3. System design: design a service or feature at scale.
4. Leadership and behaviour: team, conflict, failure and impact.
5. Hiring manager and senior leader rounds: fit, vision and expectations.

How to approach system design

1. Clarify requirements: who uses it, how many users, what must never fail.
2. State assumptions about scale and constraints.
3. Sketch the main components: clients, services, database, cache, queue.
4. Explain the data model and the key APIs.
5. Discuss bottlenecks, failures and how to scale.
6. Talk about trade-offs and monitoring, and what you would improve later.

Behavioural questions

• Tell me about a project you led from start to finish
• Describe a time you disagreed with your manager or a peer
• Tell me about a major failure and what you changed afterwards
• How do you mentor struggling team members?
• How do you prioritise when everything is urgent?

Use the STAR method

Situation, Task, Action, Result. Spend most of your time on Action and Result. Say I, not we, for your own contribution, and credit the team where due. End with what you learned.

Questions you should ask

• What does success look like in the first six months?
• How are technical decisions made here?
• What are the biggest challenges for the team right now?
• How is growth supported for senior people?

Next step

Prepare three STAR stories and one system design you have practised. Register on JobKarle and apply to senior roles.