From our research
What this interview looks like
A salary negotiation in an Indian company is usually two short conversations: HR states the offer and asks for an expectation, then the hiring manager, who owns the budget, negotiates fixed pay against variable, joining bonus, notice buy-out, title and review timing, within a band they will not reveal, and raises objections such as internal parity or a budget freeze.
A performance review follows the company's cycle, mid-year and annual, with a goal sheet, a self-rating, the manager's feedback on results and behaviours, and a rating conversation that maps to hikes and promotions through calibration. A PIP is the same conversation with documented expectations over sixty to ninety days.
A system design round is forty-five to sixty minutes with a staff or principal engineer: an open prompt, requirements and scale estimation, a high-level design, a deep dive on the hardest component, and trade-offs on failure, consistency and growth. ExamPilot compresses each into twelve to sixteen minutes with the same structure and the same rubric a real interviewer uses.
How it is weighted
System design usually decides the level at which a senior engineer is hired, and it is scored on how you frame the problem, the depth and soundness of the design, and the trade-offs you can defend. Here each stage is scored on problem framing 20, design depth 35, trade-off reasoning 25 and communication 20, with a pass mark of 65.
Who this is for
Engineers facing a system design round at product companies, high-growth start-ups or services firms' senior hiring. Choose the domain closest to the role: web-scale consumer services, data platforms and pipelines, mobile and real-time backends, or enterprise and payments integrations. No whiteboard: you describe the design out loud and the interviewer keeps the picture.
The panel focuses on
- Clarifying requirements and estimating scale before designing: users, requests per second, data size, latency and consistency
- A clear high-level design with named components and data flows, then two levels deep on the hardest part
- Caching, queues, partitioning, replication and ID generation used for a reason, with the guarantees stated correctly
- Trade-offs on failure, consistency versus availability, ten-times growth and cost, defended with mechanisms and numbers
- Narrating a design without a whiteboard so the interviewer always knows where you are
Step 1
Pick your domain
The expert on the panel probes these areas at the level of this role. Optional here; you can choose during setup.
Step 2
Choose how you want to be interviewed
1:1 interview
One interviewer runs every round and adapts the focus as you go. Lower pressure; ideal for a first attempt.
Ms. Ananya Sen
Technical lead
What to expect
5 rounds · 16 minutes
The system design interview as product and platform companies run it for mid-level and senior engineers: a staff engineer states an open-ended problem in one sentence, expects the candidate to clarify requirements and scale before drawing anything, then to propose a high-level design and go deep on the parts that matter, defend trade-offs on consistency, availability, cost and operability, and reason about failure and growth.
There is no whiteboard here; the candidate describes the design out loud and the interviewer keeps a running picture, asking them to name components, data flows and numbers. The interviewer is curious and demanding, pushes on hand-waving, offers no solutions, and respects a candidate who says I do not know but here is how I would find out.
Scored on problem framing, design depth, trade-off reasoning and communication.
- Round 1
Warm-up and the problem
· 1:00Open briefly as the staff engineer running the round, learn in one answer what kind of systems the candidate has built, and state the design problem in one sentence so the requirements stage can begin.
Ms. Ananya Sen1–1 questions - Round 2
Requirements and scale
· 4:00Act as the product and platform owner of the system: answer the candidate's clarifying questions with realistic numbers from the subject's syllabus, test whether they estimate scale, and make sure the scope is fixed before the design starts.
Ms. Ananya Sen2–3 questionsup to 1 follow-up each - Round 3
High-level design and deep dive
· 6:00Get the whole shape of the system and then go two levels deep on the hardest component for this subject: the data model, the hot path, the fan-out, the ID or ordering problem, the cache or the partitioning scheme.
Ms. Ananya Sen3–4 questionsup to 2 follow-ups each - Round 4
Trade-offs, failure and growth
· 4:00Stress the design: single points of failure, consistency versus availability for a specific feature, ten times the load, a regional outage, cost, and how the team would operate it.
Ms. Ananya Sen2–3 questionsup to 1 follow-up each - Round 5
Wrap-up
· 1:00Close the round the way a staff engineer does: thank the candidate, invite one question about the team or the stack, and end without evaluating the design aloud.
Ms. Ananya Sen0–1 questions
Meet the panel
Your AI interviewers
Distinct personas, voices and questioning styles, briefed on this role.
Ms. Ananya Sen
ChairTechnical lead
Staff engineer / technical lead
Curious, precise, collaborative.
Female voice · 3 languages
Languages
Answer in the language you think in
The panel asks in your chosen language. Switch mid-answer if you like.
- English
- Hinglish (Hindi + English)Hinglish
- বাংলাBengali
How scoring works
A report you can act on
Every round is scored on the rubric
Each interviewer scores only the criteria their round covers. Weights add up to your overall score out of 100.
Only what you actually said counts
Feedback quotes your own answers. Rounds you skip show as “Not assessed” rather than a zero.
Communication is always measured
Fluency, clarity, confidence and structure are tracked across the whole interview, in any language.
Pass mark, then a plan
You see the pass mark for this interview, your gaps, and the courses that close them fastest.
Scored on
- Problem framing and requirements20%
Does the candidate turn a one-line prompt into a scoped problem before designing? Reward asking about users, core use cases, read and write volumes, latency targets, consistency needs, data size and growth, and what is explicitly out of scope. Converting answers into rough numbers such as requests per second and storage per year.
And stating assumptions aloud when the interviewer leaves them open. Penalise jumping to technologies before requirements, never estimating scale, treating every feature as in scope, and forgetting a stated constraint later in the design.
- Design depth35%
How sound and specific is the design?
Reward a clear high-level shape with named components and the data flow between them, a sensible data model with keys and indexes, correct use of caching, queues, partitioning and replication where the scale demands them, and the ability to go two levels deeper on any component the interviewer picks, for example how the feed is fanned out, how the ID generator avoids collisions, how the rate limiter counts across nodes.
Reward knowing what a chosen database or queue actually guarantees. Penalise buzzword lists without mechanics, designs that cannot meet the stated scale, hand-waving over the hard part, and claims about a technology that are wrong.
- Trade-off reasoning25%
Does the candidate reason about alternatives, failure and cost rather than asserting a single answer? Reward naming two options and choosing with a reason, discussing consistency versus availability for the specific feature, identifying single points of failure and bottlenecks and fixing them, reasoning about what breaks at ten times the load, estimating cost drivers, and considering operability: monitoring, deploys, migrations.
Reward honest limits: this design would not survive a regional outage and here is what that would take. Penalise refusing to pick, picking without a reason, ignoring failure modes, and over-engineering for scale the requirements do not have.
- Communication20%
Can the candidate keep an interviewer oriented in a design with no whiteboard? Reward narrating the structure top-down, naming components consistently, summarising the current design before going deeper, checking in with the interviewer before switching topics, and answering the question asked.
Penalise jumping between components, renaming things mid-way, long monologues without a check-in, and answering a deep-dive question with a restatement of the overview.
Pass mark 65 / 100 · System design round — a staff engineer walks you through designing a real system
Keep exploring
More Workplace scenarios interviews
- Workplace scenarios Salary negotiation interviewFreshers with an offer in hand, professionals switching jobs, employees in an appraisal cycle, and independent consultants pricing a contract
- Workplace scenarios Performance review interviewEmployees in a mid-year or annual review cycle, anyone on or expecting a performance improvement plan, and those preparing a promotion case