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Ms Technology Software Engineer Interview Guide

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

The 60-second brief

A Software Engineer at Ms Technology plays a pivotal role in designing, developing, and maintaining high-performance software systems. In this position, you will be responsible for translating complex business requirements into robust, scalable, and clean code. The engineering team focuses on building efficient applications that directly impact product delivery, system reliability, and overall client satisfaction. At Ms Technology, software development is treated as both a craft and a science. Engineers work closely with cross-functional teams to solve challenging technical problems, optimize database queries, and implement modern software design patterns. Because the company values agility and rapid execution, your contributions will have a direct and visible impact on the systems that power daily business operations.

This guide is scoped to a Software Engineer candidate at Ms Technology.

Focus areas

  • Java
  • Core Java (fundamentals)
  • Strings (string manipulation)

The Ms Technology interview process

Ms Technology candidates report 4 rounds over 3-5 weeks. The stages below are what candidates describe, not a published process.

Written Evaluation

Multi-part written test assessing cognitive aptitude and technical coding abilities.

What to demonstrate

  • Multi-part written test assessing cognitive aptitude and technical coding abilities
  • Depth in Java

How to prepare

  • Answer aloud and timed: Explain the difference between method overloading and method overriding in Java.
  • Answer aloud and timed: How does the garbage collector manage memory, and can you force garbage collection?

Technical Interviews

Intensive face-to-face interviews starting with core concepts and advancing to application scenarios.

What to demonstrate

  • Intensive face-to-face interviews starting with core concepts and advancing to application scenarios
  • Depth in Java

How to prepare

  • Answer aloud and timed: What are the main differences between an interface and an abstract class?
  • Answer aloud and timed: Explain the life cycle of a thread in Java and how to prevent deadlocks.

Conversation with Founder

Direct discussion with the company founder to assess fit and alignment.

What to demonstrate

  • Direct discussion with the company founder to assess fit and alignment
  • Depth in Java

How to prepare

  • Answer aloud and timed: How does the HashMap class work internally in Java?
  • Answer aloud and timed: How do you reverse a singly linked list in C++?

HR Alignment Round

Final round with HR to finalize discussions and align on expectations.

What to demonstrate

  • Final round with HR to finalize discussions and align on expectations
  • Depth in Java

How to prepare

  • Answer aloud and timed: Explain the concept of pointers and references, and when you would use each.
  • Answer aloud and timed: Write a program to find the first non-repeating character in a C++ string.

Where candidates lose points

Study Classic Textbooks

Candidates have noted that practicing objective and output-type questions from classic academic programming books (such as those by E. Balagurusamy for Java and C++) is highly beneficial for clearing the written test.

Explain Your Code Out Loud

During the F2F technical round, do not code in silence. Talk your interviewer through your logic, explain why you chose a specific loop or data structure, and discuss any trade-offs you are making.

Be Ready for Tricky Questions

Interviewers are known to ask conceptual questions that sound simple but have subtle traps. Take a moment to think before answering, especially when discussing multi-threading or memory management.

Questions & practice

How does the garbage collector manage memory, and can you force garbage collection?

Medium · Core Java & Object-Oriented Programming

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?

How do you reverse a singly linked list in C++?

Medium · C/C++ Programming & Data Structures

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?

Explain the concept of pointers and references, and when you would use each.

Medium · C/C++ Programming & Data Structures

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 find the first non-repeating character in a C++ string.

Medium · C/C++ Programming & Data Structures

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?

Explain the virtual destructor concept in C++ and why it is necessary.

Medium · C/C++ Programming & Data Structures

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?

Find version gaps and relay lag with window functions

Medium · window functions · event tables · frame semantics

outbox_event holds event_id, aggregate_type, aggregate_id, aggregate_version, event_type, payload, status ('pending','published','dead'), attempts, created_at, published_at. A projection is missing rows and you must decide whether the relay skipped events or the consumer dropped them. Write three queries over the last seven days: one listing every aggregate_id whose published aggregate_version sequence has a hole, one giving per-day counts with a running total, and one returning the newest published event per aggregate. For each, say where the window function is evaluated relative to WHERE and LIMIT. PostgreSQL 16.

Approach

  1. Gaps: compute lead(aggregate_version) OVER (PARTITION BY aggregate_id ORDER BY aggregate_version) in a subquery, then filter next_version <> aggregate_version + 1 in the outer query. Window functions are evaluated after WHERE, GROUP BY and HAVING and before the outer ORDER BY and LIMIT, so the predicate cannot sit in the same WHERE clause and PostgreSQL 16 has no QUALIFY.
  2. Say what the seven-day filter does to the answer: it truncates every partition, so the first row per aggregate has no predecessor inside the window and a hole spanning the boundary is invisible. Widen the window, or join to resource.version as the authority for the true maximum.
  3. Running total: SELECT date_trunc('day', created_at) AS d, count() AS n, sum(count()) OVER (ORDER BY date_trunc('day', created_at) ROWS UNBOUNDED PRECEDING). An aggregate inside a window call is legal because grouping runs before windowing. The grouping key is unique per row here so ROWS and RANGE agree, but write the frame anyway — over ungrouped rows with tied timestamps the default RANGE frame pulls in every peer row and the total jumps.
  4. Newest per aggregate: DISTINCT ON (aggregate_id) ... ORDER BY aggregate_id, aggregate_version DESC is the cheap PostgreSQL-only form when an index matches that order; row_number() OVER (PARTITION BY aggregate_id ORDER BY aggregate_version DESC) = 1 is the portable form and needs a subquery for the same evaluation-order reason as the gap query.

Follow-up

  • Relay failover redelivers events. Does a duplicate break the gap query, and how would you detect one from this table alone?
  • Turn the gap check into a continuous monitor rather than a query someone runs after an incident. What does it watch?

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

  1. 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.
  2. 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.
  3. 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.
  4. 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?

Explain the difference between method overloading and method overriding in Java.

Medium · Core Java & Object-Oriented Programming

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?

What are the main differences between an interface and an abstract class?

Medium · Core Java & Object-Oriented Programming

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 does the HashMap class work internally in Java?

Medium · Core Java & Object-Oriented Programming

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?

What is the difference between a Servlet and a JSP?

Medium · Web Basics & Enterprise Java

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 request life cycle in a typical Servlet container.

Medium · Web Basics & Enterprise Java

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?

What are the different HTTP methods, and when should you use POST versus PUT?

Medium · Web Basics & Enterprise Java

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 life cycle of a thread in Java and how to prevent deadlocks.

Medium · Core Java & Object-Oriented Programming

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?

What is a memory leak in C++, and how can you prevent it?

Medium · C/C++ Programming & Data Structures

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 Ms Technology candidates report.

Day 1 — Map the Ms Technology loop

  • Write out the reported sequence: Written Evaluation, Technical Interviews, Conversation with Founder, HR Alignment Round.
  • 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 4 reported rounds, with the weakest marked.

Day 2 — Work Java

  • Spend the session on Java, which Ms Technology candidates report being tested on.
  • Write one worked example in Java and time yourself on it.

Deliverable: One timed worked example in Java.

Day 3 — Work Core Java (fundamentals)

  • Spend the session on Core Java (fundamentals), which Ms Technology candidates report being tested on.
  • Write one worked example in Core Java (fundamentals) and time yourself on it.

Deliverable: One timed worked example in Core Java (fundamentals).

Day 4 — Work Strings (string manipulation)

  • Spend the session on Strings (string manipulation), which Ms Technology candidates report being tested on.
  • Write one worked example in Strings (string manipulation) and time yourself on it.

Deliverable: One timed worked example in Strings (string manipulation).

Day 5 — Answer out loud: Core Java & Object-Oriented Programming

  • Answer aloud, timed: Explain the difference between method overloading and method overriding in Java.
  • Answer aloud, timed: How does the garbage collector manage memory, and can you force garbage collection?

Deliverable: Spoken answers to 2 reported Core Java & Object-Oriented Programming question(s), under time.

Day 6 — Answer out loud: C/C++ Programming & Data Structures

  • Answer aloud, timed: How do you reverse a singly linked list in C++?
  • Answer aloud, timed: Explain the concept of pointers and references, and when you would use each.

Deliverable: Spoken answers to 2 reported C/C++ Programming & Data Structures question(s), under time.

Day 7 — Answer out loud: Web Basics & Enterprise Java

  • Answer aloud, timed: What is the difference between a Servlet and a JSP?
  • Answer aloud, timed: Explain the request life cycle in a typical Servlet container.

Deliverable: Spoken answers to 2 reported Web Basics & Enterprise Java question(s), under time.

Behavioural preparation

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

How do you handle session management in a web-based application?

Medium · Web Basics & Enterprise Java

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?

Ship under a deadline and bound the debt you chose

Medium · pagination · technical debt · tradeoffs

You have four days to ship a tenant-facing listing endpoint. The version you would defend uses keyset pagination over (tenant_id, status, updated_at DESC, resource_id DESC); the version you can finish uses LIMIT/OFFSET with no matching index. Describe a deadline call you actually made of this shape: what you shipped, what you knowingly deferred, how you bounded the damage with a mechanism rather than an intention, and the specific numeric condition that would force the follow-up. Name who you told and where you wrote it down.

Approach

  1. Name the deferred failure precisely instead of calling it slow. OFFSET n makes the database produce and discard n rows, so cost grows with page depth; without an index matching the sort, every matching row is read and sorted before the limit applies; and rows inserted between two page fetches shift across the boundary so items are skipped or repeated with nothing in the response to signal it.
  2. Bound the blast radius with something mechanical rather than a promise: cap maximum page depth, cap page size, restrict the endpoint to one internal caller, or keep it behind a flag. State which failure each cap removes and which it leaves standing.
  3. Attach a number to the trigger and wire it to an alarm: the first tenant crossing N resources, or the endpoint's p99 crossing its share of the 400 ms budget, so the debt announces itself instead of waiting to be remembered.
  4. Write it where the next engineer looks, which is the code and the ticket, not a chat message: what was deferred, why, the cap, and the trigger.

Follow-up

  • At what page depth does the offset version breach your latency budget, given your page size and row counts?
  • What breaks first when you switch to keyset pagination later, and what does a client holding an old page token see?

Argue against a design, lose, and commit anyway

Medium · disagreement · service boundaries · decision records

Describe a design you argued against and lost. State the failure you predicted as a named mechanism, not a feeling about complexity: two services that would need one transaction, a projection with no rebuild path, a write path with no idempotency key. Say what evidence you brought, what the decision maker weighed instead, and what you did after the decision was made: what you instrumented, what you wrote down, and whether the prediction came true. Five minutes.

Approach

  1. State the prediction in falsifiable form up front: the mechanism, the condition that triggers it, and the observable outcome. A prediction that cannot be checked also cannot be credited to you later.
  2. Show the evidence you had at the time and label each piece honestly as measured, analogous, or intuition. Keeping the intuition is fine; disguising it as data is the thing that erodes your standing in the next argument.
  3. Represent the opposing case at full strength, including the constraint you did not control: a fixed date, a team boundary, or the fact that the decision was cheap to reverse and yours was not.
  4. Make disagree-and-commit concrete. Name the artefact you left behind so the prediction could be settled without you: the alert and its threshold, the counter on the dashboard, the decision note that recorded the trade-off and the condition that would revisit it.

Follow-up

  • What threshold on that alert would have proved you right, and did anyone ever look at it?
  • If the same proposal arrived tomorrow with the same deadline, would you argue it the same way?