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Exela Technologies Software Engineer Interview Guide

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

The 60-second brief

A Software Engineer at Exela Technologies plays a pivotal role in developing and maintaining the complex digital solutions that drive the company’s business process automation services. You will be tasked with building scalable software, optimizing data architectures, and integrating advanced technologies to support global operations. Whether working on enterprise-grade applications or specialized IoT and cloud initiatives, your code directly impacts the efficiency and reliability of systems used by major organizations worldwide. This position demands a blend of rigorous technical proficiency and a practical, problem-solving mindset. You will often operate at the intersection of development, system architecture, and client-specific requirements.

This guide is scoped to a Software Engineer candidate at Exela Technologies.

Focus areas

  • OOP (Object-Oriented Programming)
  • C#
  • SQL

The Exela Technologies interview process

Exela Technologies candidates report 3 rounds over 3-5 weeks. The stages below are what candidates describe, not a published process.

Initial Screening

Assessment of your technical fundamentals to gauge baseline knowledge.

What to demonstrate

  • Assessment of your technical fundamentals to gauge baseline knowledge
  • Depth in OOP (Object-Oriented Programming)

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 Discussions

In-depth, one-on-one technical discussions to evaluate your problem-solving skills.

What to demonstrate

  • In-depth, one-on-one technical discussions to evaluate your problem-solving skills
  • Depth in OOP (Object-Oriented Programming)

How to prepare

  • Answer aloud and timed: Describe the process of optimizing a slow-running query in SQL Server.
  • Answer aloud and timed: How do you implement dependency injection in an ASP.NET MVC application?

Managerial Evaluations

Assessment by managerial staff to evaluate fit within the team and company.

What to demonstrate

  • Assessment by managerial staff to evaluate fit within the team and company
  • Depth in OOP (Object-Oriented Programming)

How to prepare

  • Answer aloud and timed: Explain the concept of LINQ and provide an example of its use in data manipulation.
  • Answer aloud and timed: Write a program to demonstrate polymorphism in a real-world scenario.

Where candidates lose points

Dress formally

Regardless of the interview mode, dressing in professional attire is expected at Exela Technologies and shows respect for the process.

Review your resume

Be prepared to discuss every project listed on your resume in detail, including the specific technologies you used and the problems you solved.

Read the Job Description

Requirements can vary significantly by team (e.g., some teams prioritize Java, others.NET). Tailor your preparation to the specific tech stack mentioned in your invitation.

Ask questions

At the end of your technical rounds, ask the interviewer about the team's current projects or their approach to development. It demonstrates engagement and curiosity.

Questions & practice

How do you handle memory management and garbage collection in C#?

Medium · Technical and Domain Proficiency

Approach

  1. Say what the runtime actually does before reasoning about the code.
  2. Name what is shared across threads and what owns each piece of state.
  3. Identify the window where an invariant is briefly untrue.
  4. Distinguish a value from a reference to it, and say which one you handed out.

Follow-up

  • What happens if two callers reach this at the same time?
  • Where could this allocate more than you expect?

Write a program to demonstrate polymorphism in a real-world scenario.

Medium · Problem-Solving and Coding

Approach

  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. 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 specific error-handling requirement, how would you structure your code to ensure system stability?

Medium · Problem-Solving and Coding

Approach

  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. 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?

Describe the process of optimizing a slow-running query in SQL Server.

Medium · Technical and Domain Proficiency

Approach

  1. Name the grain you start from and join outward from it.
  2. Check whether any join is one-to-many before aggregating, or the sums inflate.
  3. Say which index the query would use, and what makes it unusable.
  4. Handle the rows that do not match: that is usually the actual question.

Follow-up

  • How does the query change if that join becomes one-to-many?
  • What happens to this when the table is ten times larger?

Explain why the owner filter ignores the listing index

Medium · composite index · query plans · sort elimination

The only index on resource is (tenant_id, status, updated_at DESC, resource_id DESC). A new endpoint returns one user's resources across all statuses, newest created first: WHERE tenant_id = $1 AND owner_user_id = $2 ORDER BY created_at DESC LIMIT 20. On a tenant with 2M rows it takes 900 ms and EXPLAIN shows a sort above a large scan. Explain precisely why the existing index cannot serve it, give the index that can, and state which of these the new index still will not help: owner_user_id alone across tenants; the same query ordered by updated_at. PostgreSQL 16.

Approach

  1. Separate the two jobs an index does. For filtering, a composite btree is seekable only on a left prefix, so with no predicate on status the scan can at best range over tenant_id and test owner_user_id per row; PostgreSQL 16 has no btree skip scan to jump the unconstrained column.
  2. For ordering, the index is sorted by (status, updated_at) within a tenant and not by created_at, so the LIMIT cannot stop early: every matching row is read and then sorted. That is the 'Sort Method: top-N heapsort' line, and it is why the plan reads 2M rows to answer with 20.
  3. Derive the replacement from the access path — equality, equality, then the ordering column: CREATE INDEX CONCURRENTLY ON resource (tenant_id, owner_user_id, created_at DESC). The scan seeks to the (tenant, owner) range and walks 20 entries in order, so the Sort node disappears along with the row-read.
  4. Treat INCLUDE (title, status) as conditional, not free. An index-only scan still visits the heap for any row whose page is not marked all-visible, so on a table taking 1.2k writes/second the win depends on autovacuum keeping the visibility map current, and the wider index costs more on every insert.

Follow-up

  • 90% of rows are status='active'. Would a partial index WHERE status = 'active' change your answer, and for which of the three queries?
  • A dashboard runs this for 40 owners in one page load. What changes about the design?

Explain the difference between an interface and an abstract class in OOPS.

Medium · Technical and Domain Proficiency

Approach

  1. Clarify what is being asked and what a complete answer contains.
  2. State your assumptions explicitly before working the problem.
  3. Say what you would check first and why it is the highest-information step.
  4. Work from the requirement backwards to the design.

Follow-up

  • What assumption would you test first?
  • How would you know your answer was wrong?

How do you implement dependency injection in an ASP.NET MVC application?

Medium · Technical and Domain Proficiency

Approach

  1. Clarify what is being asked and what a complete answer contains.
  2. State your assumptions explicitly before working the problem.
  3. Say what you would check first and why it is the highest-information step.
  4. Work from the requirement backwards to the design.

Follow-up

  • What assumption would you test first?
  • How would you know your answer was wrong?

Explain the concept of LINQ and provide an example of its use in data manipulation.

Medium · Technical and Domain Proficiency

Approach

  1. Clarify what is being asked and what a complete answer contains.
  2. State your assumptions explicitly before working the problem.
  3. Say what you would check first and why it is the highest-information step.
  4. Work from the requirement backwards to the design.

Follow-up

  • What assumption would you test first?
  • How would you know your answer was wrong?

How would you design a database schema for an ETL process?

Medium · Problem-Solving and Coding

Approach

  1. Fix the scope first: who calls this, how often, and what they do when it fails.
  2. Name the read and write paths separately; they rarely have the same bottleneck.
  3. Choose a partition key and say what query it makes expensive.
  4. State the consistency you need, and where you are willing to be stale.

Follow-up

  • What breaks first when traffic grows ten times?
  • How does this behave when that dependency is down for an hour?

Describe how you would integrate IoT devices with an Azure or AWS backend.

Medium · Problem-Solving and Coding

Approach

  1. Say who the caller is and what they do when the call fails halfway.
  2. Define the identity of a request so a retry cannot double-apply it.
  3. Separate accepted, pending, failed and confirmed; they are different facts.
  4. Design the error taxonomy before the success shape; callers branch on it.

Follow-up

  • What happens if the caller retries after a timeout?
  • How does a client discover it is on an old version of this contract?

How do you approach debugging a multi-threaded application?

Medium · Problem-Solving and Coding

Approach

  1. Establish what changed and when, before forming any theory.
  2. Pick a bisection that eliminates candidates whichever way it turns out.
  3. Check the instrumentation before believing the symptom.
  4. Separate the trigger from the cause; the deploy is rarely the bug.

Follow-up

  • What would you look at first, and what would it rule out?
  • How would you tell a cause from a coincidence here?

Suggested practice checklist

Built from the rounds and topics Exela Technologies candidates report.

Day 1 — Map the Exela Technologies loop

  • Write out the reported sequence: Initial Screening, Technical Discussions, Managerial Evaluations.
  • For each round, write one sentence on what it is judging, from the description above, and mark the one you are least ready for.

Deliverable: A one-page map of the 3 reported rounds, with the weakest marked.

Day 2 — Work OOP (Object-Oriented Programming)

  • Spend the session on OOP (Object-Oriented Programming), which Exela Technologies candidates report being tested on.
  • Write one worked example in OOP (Object-Oriented Programming) and time yourself on it.

Deliverable: One timed worked example in OOP (Object-Oriented Programming).

Day 3 — Work C#

  • Spend the session on C#, which Exela Technologies candidates report being tested on.
  • Write one worked example in C# and time yourself on it.

Deliverable: One timed worked example in C#.

Day 4 — Work SQL

  • Spend the session on SQL, which Exela Technologies candidates report being tested on.
  • Write one worked example in SQL and time yourself on it.

Deliverable: One timed worked example in SQL.

Day 5 — Answer out loud: Technical and Domain Proficiency

  • Answer aloud, timed: Explain the difference between an interface and an abstract class in OOPS.
  • Answer aloud, timed: How do you handle memory management and garbage collection in C#?

Deliverable: Spoken answers to 2 reported Technical and Domain Proficiency question(s), under time.

Day 6 — Answer out loud: Problem-Solving and Coding

  • Answer aloud, timed: Write a program to demonstrate polymorphism in a real-world scenario.
  • Answer aloud, timed: How would you design a database schema for an ETL process?

Deliverable: Spoken answers to 2 reported Problem-Solving and Coding question(s), under time.

Day 7 — Answer out loud: Behavioral and Process

  • Answer aloud, timed: Describe a challenging project you worked on and the specific technical solutions you provided.
  • Answer aloud, timed: How do you handle situations where you have conflicting requirements from different stakeholders?

Deliverable: Spoken answers to 2 reported Behavioral and Process question(s), under time.

Behavioural preparation

Behavioural rounds judge the decision you made and what it cost.

Describe a challenging project you worked on and the specific technical solutions you provided.

Medium · Behavioral and Process

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.

Follow-up

  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?

How do you handle situations where you have conflicting requirements from different stakeholders?

Medium · Behavioral and Process

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.

Follow-up

  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?

Tell us about a time you had to learn a new technology on the fly to meet a project deadline.

Medium · Behavioral and Process

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.

Follow-up

  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?

How do you manage your time when juggling multiple technical tasks or bug fixes?

Medium · Behavioral and Process

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.

Follow-up

  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?

Describe your experience working in an Agile/Scrum environment.

Medium · Behavioral and Process

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. Name the disagreement and how you resolved it with evidence.

Follow-up

  • What would you do differently if you ran that again?
  • How did you know your change caused the improvement?