Interview guides · Bourntec Solutions

Bourntec Solutions Software Engineer Interview Guide

Bourntec Solutions Software Engineer interview guide: reported rounds, questions and how candidates describe the process.

The 60-second brief

A Software Engineer at Bourntec Solutions plays a pivotal role in developing innovative software solutions that drive business success. This position is essential because it directly impacts the quality and performance of products that meet client needs, ultimately enhancing user experiences and satisfaction. As a Software Engineer, you will engage with cross-functional teams to create scalable applications, ensuring that the software not only meets technical specifications but also aligns with business objectives. In this role, you will work on critical projects that leverage cutting-edge technologies and methodologies, contributing to both the strategy and execution of software development. You will have the opportunity to tackle complex challenges, such as optimizing existing software systems and integrating new technologies.

This guide is scoped to a Software Engineer candidate at Bourntec Solutions.

Focus areas

Python
Object-Oriented Programming (OOP)
OOPS Concepts

The Bourntec Solutions interview process

Bourntec Solutions candidates report 5 rounds over 4-6 weeks. The stages below are what candidates describe, not a published process.

Application Review

Initial review of submitted applications to assess qualifications and fit.

What to demonstrate

Initial review of submitted applications to assess qualifications and fit
Depth in Python

How to prepare

Be able to walk your CV end to end in two minutes, and say why this company specifically.
Have your salary expectations, notice period and location constraints ready, and ask for the rest of the loop in writing.

Technical Interviews

Series of interviews focusing on technical skills and problem-solving abilities.

What to demonstrate

Series of interviews focusing on technical skills and problem-solving abilities
Depth in Python

How to prepare

Answer aloud and timed: Can you describe exception handling in Python?
Answer aloud and timed: How do you ensure code quality and maintainability?

Coding Challenges

Candidates complete coding challenges to demonstrate programming skills.

What to demonstrate

Candidates complete coding challenges to demonstrate programming skills
Depth in Python

How to prepare

Answer aloud and timed: What is the difference between a list and a tuple in Python?
Answer aloud and timed: How would you approach debugging a complex application?

Behavioral Assessments

Evaluation of interpersonal skills and cultural fit through behavioral questions.

What to demonstrate

Evaluation of interpersonal skills and cultural fit through behavioral questions
Depth in Python

How to prepare

Prepare three examples from your own work, each with a decision you made and an outcome you can quantify.
Re-read the description of the behavioral assessments above and write down what you would ask to confirm before it.

Final Discussions

Engagement with various interviewers to discuss overall fit and expectations.

What to demonstrate

Engagement with various interviewers to discuss overall fit and expectations
Depth in Python

How to prepare

Answer aloud and timed: Write a function to count the number of repeated words in a sentence.
Answer aloud and timed: Given a list of integers, how would you find the maximum sum of non-adjacent elements?

Where candidates lose points

Practice coding challenges

Regularly engage with coding platforms to sharpen your problem-solving skills.

Prepare for behavioral questions

Reflect on past experiences that showcase your teamwork and adaptability.

Understand the company’s products

Familiarize yourself with Bourntec Solutions' offerings and how your role contributes to their success.

Ask insightful questions

Prepare questions that show your interest in the company and the role during the interview.

Questions & practice

Write a function to count the number of repeated words in a sentence.

Medium · Coding / Algorithms

Approach

Restate the input: its shape, its size, and what is guaranteed about it.
Name the brute-force solution and its complexity before improving on it.
Choose the data structure from the access pattern, not from familiarity.
State the target complexity and say which constraint rules the naive version out.

Follow-up

How does this change if the input no longer fits in memory?
What is the worst case, and how likely is it on real data?

Given a list of integers, how would you find the maximum sum of non-adjacent elements?

Medium · Coding / Algorithms

Approach

Restate the input: its shape, its size, and what is guaranteed about it.
Name the brute-force solution and its complexity before improving on it.
Choose the data structure from the access pattern, not from familiarity.
State the target complexity and say which constraint rules the naive version out.

Follow-up

How does this change if the input no longer fits in memory?
What is the worst case, and how likely is it on real data?

Implement a basic algorithm for sorting data.

Medium · Coding / Algorithms

Approach

Restate the input: its shape, its size, and what is guaranteed about it.
Name the brute-force solution and its complexity before improving on it.
Choose the data structure from the access pattern, not from familiarity.
State the target complexity and say which constraint rules the naive version out.

Follow-up

How does this change if the input no longer fits in memory?
What is the worst case, and how likely is it on real data?

Replace offset paging on the resource feed with keyset

Easy · keyset pagination · composite index · sort order

resource holds resource_id, tenant_id, owner_user_id, title, body_ref, version, status ('draft','active','archived','deleted'), created_at, updated_at, deleted_at, with an index on (tenant_id, status, updated_at DESC, resource_id DESC). The listing endpoint returns active resources for one tenant, newest update first, 50 per page, today with LIMIT 50 OFFSET n. Tenants reach page 400 and rows are created while they read. Write the keyset query, define what the cursor carries and how it is encoded, and say which part of the index each predicate uses. Assume PostgreSQL 16.

Approach

Name the two failures separately. OFFSET 20000 makes the server produce and discard 20,000 rows, so page cost grows with depth rather than with page size. Independently, any write that changes how many rows sort above the offset moves the window between two fetches, and the direction decides which anomaly you get: an insert lands at the head of updated_at DESC and pushes already-returned rows down past the boundary, so they are returned a second time; a delete above the offset, or a row whose updated_at is bumped above the cursor, pulls rows up and one is never returned at all. Nothing in the response reveals either.
Write the seek: WHERE tenant_id = $1 AND status = 'active' AND (updated_at, resource_id) < ($2, $3) ORDER BY updated_at DESC, resource_id DESC LIMIT 50. The row-value comparison is one index range rather than a disjunction, and both columns are NOT NULL, which is what makes that comparison well defined.
Map each predicate onto the index: tenant_id and status are equality on the leading columns, (updated_at, resource_id) is the range, and the ORDER BY matches the index order so no Sort node appears and the scan stops after 50 rows. The DESC in the definition only matters for mixed directions — a plain ascending btree on the same columns is read backwards for this query.
Put both sort columns in the cursor and nothing the client can tamper with into another tenant: base64 of (updated_at, resource_id), validated server-side, with tenant_id taken from the principal.

Follow-up

The client asks for 'jump to page 400'. What do you offer instead, and what does the honest version cost?
Sort order becomes user-selectable across four columns. How many indexes is that, and which would you refuse to add?

Stop tag and share joins from fanning out a page

Medium · join fan-out · semi-joins · many-to-many

resource_tag is (resource_id, tag_id) with PK (resource_id, tag_id); resource_share is (resource_id, shared_with_user_id, permission). The tagged-and-shared listing inner-joins resource to both, filters tenant_id, tag_id = ANY($2) and shared_with_user_id = $3, orders by updated_at DESC and takes 50. Pages come back with fewer than 50 distinct resources and the total in the header is far too high. Explain the row multiplication, rewrite both the page query and the count query so each is correct, and name the index each one needs. PostgreSQL 16.

Approach

Do the arithmetic against the predicates that are actually there. An inner join emits one row per matching child row, and both joins are filtered: tag_id = ANY($2) admits only the requested tags, shared_with_user_id = $3 admits one user's share rows. So a resource holding three of the requested tags and shared with $3 once yields three rows, not one — the multiplier is its count of matching tags times its share rows for that single user, and that second factor is 1 unless the table admits duplicate (resource_id, shared_with_user_id) pairs. LIMIT 50 then limits rows rather than resources, and COUNT(*) counts pairs — the header is the product, not the population.
Reject DISTINCT as the fix. It deduplicates after the product has been built, so the planner must materialise and sort the fanned-out set before the LIMIT can apply, and it leaves any SUM or AVG in the same select list wrong.
Rewrite both filters as semi-joins, keeping resource as the only row source: AND EXISTS (SELECT 1 FROM resource_tag rt WHERE rt.resource_id = r.resource_id AND rt.tag_id = ANY($2)) and the same shape against resource_share. A semi-join stops at the first match per resource and preserves the driving index order, so ORDER BY updated_at DESC, resource_id DESC LIMIT 50 still stops after 50 rows.
Count with the same predicates and no join at all: SELECT count(*) FROM resource r WHERE r.tenant_id = $1 AND r.status = 'active' AND EXISTS (...) AND EXISTS (...). Nothing multiplies a resource, so the number is the population.

Follow-up

The filter changes from 'any of these tags' to 'all of these tags'. Rewrite it and state what it costs relative to the ANY form.
A resource can be shared with the same user twice under different permissions. Does your count change, and should it?