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Voya Investment Management Software Engineer Interview Guide

Voya Investment Management Software Engineer interview guide: reported rounds, questions and how candidates describe the process.

The 60-second brief

A Software Engineer at Voya Investment Management plays a pivotal role in bridging the gap between complex financial strategies and robust, scalable technology solutions. As a leading asset manager, Voya Investment Management relies heavily on its engineering teams to build, optimize, and maintain high-performance platforms that handle billions of dollars in assets. The systems you develop and support will directly impact portfolio managers, research analysts, and risk officers, enabling them to make data-driven decisions in real time. In this role, you will work at the intersection of finance and modern software engineering. The engineering culture values stability, precision, and performance, given the critical nature of financial transactions and data processing.

This guide is scoped to a Software Engineer candidate at Voya Investment Management.

Focus areas

  • Java
  • Spring Boot
  • Distributed Systems

The Voya Investment Management interview process

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

Initial Screening

Begins with a phone screen or online technical assessment to verify fundamental technical skills and resume details.

What to demonstrate

  • Begins with a phone screen or online technical assessment to verify fundamental technical skills and resume details
  • Depth in Java

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.

Core Technical Rounds

Conducted by experienced engineers to evaluate coding abilities, system design knowledge, and familiarity with core concepts.

What to demonstrate

  • Conducted by experienced engineers to evaluate coding abilities, system design knowledge, and familiarity with core concepts
  • Depth in Java

How to prepare

  • Answer aloud and timed: Write a query to find the second-highest salary from an employee database, and explain how you would index the table to optimize this search.
  • Answer aloud and timed: Explain the lifecycle of a bean in the Spring framework.

Managerial Discussions

Final stages involve hiring managers and senior leadership focusing on behavioral fit and architectural oversight.

What to demonstrate

  • Final stages involve hiring managers and senior leadership focusing on behavioral fit and architectural oversight
  • Depth in Java

How to prepare

  • Answer aloud and timed: Describe a scenario where you had to debug a performance bottleneck in a relational database. What tools and strategies did you use?
  • Answer aloud and timed: What is the difference between horizontal and vertical scaling, and when would you choose one over the other in a distributed environment?

Where candidates lose points

Master the fundamentals

Do not overlook basic computer science concepts. Be highly comfortable with standard data structures like linked lists, trees, and hash maps, as they frequently appear in technical screens.

Be prepared for code reviews

Practice reading and critiquing code. Being able to quickly spot inefficiencies, security flaws, or poor styling in someone else's code is a highly valued skill in their collaborative engineering environment.

During technical rounds, do not try to guess or fake an answer if you do not know a specific concept

The interviewers value honesty and intellectual integrity; it is always better to explain your current understanding and ask clarifying questions.

Questions & practice

How does the garbage collection mechanism work in Java, and how do you optimize memory management for high-thr

Medium · Core Java & Backend Development

How does the garbage collection mechanism work in Java, and how do you optimize memory management for high-throughput applications?

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?

Implement a function to reverse a singly linked list, both iteratively and recursively.

Medium · Data Structures & Algorithms

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?

How do you detect a cycle in a linked list? Explain the time and space complexity of your approach.

Medium · Data Structures & Algorithms

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 an array of integers, find the contiguous subarray with the largest sum.

Medium · Data Structures & Algorithms

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 difference between a hash map and a binary search tree in terms of lookup and insertion time compl

Medium · Data Structures & Algorithms

Explain the difference between a hash map and a binary search tree in terms of lookup and insertion time complexities.

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?

How would you implement a queue using two stacks?

Medium · Data Structures & Algorithms

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?

Write a query to find the second-highest salary from an employee database, and explain how you would index the

Medium · Core Java & Backend Development

Write a query to find the second-highest salary from an employee database, and explain how you would index the table to optimize this search.

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 optimistic and pessimistic locking in Spring Boot and how you would implement t

Medium · Core Java & Backend Development

Explain the difference between optimistic and pessimistic locking in Spring Boot and how you would implement them.

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 lifecycle of a bean in the Spring framework.

Medium · Core Java & Backend Development

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 horizontal and vertical scaling, and when would you choose one over the other i

Medium · Distributed Systems & Architecture

What is the difference between horizontal and vertical scaling, and when would you choose one over the other in a distributed environment?

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?

Explain the concept of eventual consistency and how it applies to microservices architecture.

Medium · Distributed Systems & Architecture

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?

How do you handle distributed transactions across multiple microservices without compromising system reliabili

Medium · Distributed Systems & Architecture

How do you handle distributed transactions across multiple microservices without compromising system reliability?

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 the CAP theorem and explain which trade-offs you would make when designing a portfolio tracking syste

Medium · Distributed Systems & Architecture

Describe the CAP theorem and explain which trade-offs you would make when designing a portfolio tracking system.

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?

How would you design a rate limiter for an API gateway that serves external clients?

Medium · Distributed Systems & Architecture

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?

Describe a scenario where you had to debug a performance bottleneck in a relational database. What tools and s

Medium · Core Java & Backend Development

Describe a scenario where you had to debug a performance bottleneck in a relational database. What tools and strategies did you use?

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 Voya Investment Management candidates report.

Day 1 — Map the Voya Investment Management loop

  • Write out the reported sequence: Initial Screening, Core Technical Rounds, Managerial Discussions.
  • 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 Java

  • Spend the session on Java, which Voya Investment Management 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 Spring Boot

  • Spend the session on Spring Boot, which Voya Investment Management candidates report being tested on.
  • Write one worked example in Spring Boot and time yourself on it.

Deliverable: One timed worked example in Spring Boot.

Day 4 — Work Distributed Systems

  • Spend the session on Distributed Systems, which Voya Investment Management candidates report being tested on.
  • Write one worked example in Distributed Systems and time yourself on it.

Deliverable: One timed worked example in Distributed Systems.

Day 5 — Answer out loud: Core Java & Backend Development

  • Answer aloud, timed: Explain the difference between optimistic and pessimistic locking in Spring Boot and how you would implement them.
  • Answer aloud, timed: How does the garbage collection mechanism work in Java, and how do you optimize memory management for high-throughput applications?

Deliverable: Spoken answers to 2 reported Core Java & Backend Development question(s), under time.

Day 6 — Answer out loud: Distributed Systems & Architecture

  • Answer aloud, timed: What is the difference between horizontal and vertical scaling, and when would you choose one over the other in a distributed environment?
  • Answer aloud, timed: Explain the concept of eventual consistency and how it applies to microservices architecture.

Deliverable: Spoken answers to 2 reported Distributed Systems & Architecture question(s), under time.

Day 7 — Answer out loud: Data Structures & Algorithms

  • Answer aloud, timed: Implement a function to reverse a singly linked list, both iteratively and recursively.
  • Answer aloud, timed: How do you detect a cycle in a linked list? Explain the time and space complexity of your approach.

Deliverable: Spoken answers to 2 reported Data Structures & Algorithms question(s), under time.

Behavioural preparation

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

Describe a time when you had to work with a highly opinionated teammate or stakeholder. How did you resolve an

Medium · Behavioral & Professional Experience

Describe a time when you had to work with a highly opinionated teammate or stakeholder. How did you resolve any technical disagreements?

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 me about a challenging project you delivered. What were the technical hurdles, and how did you overcome t

Medium · Behavioral & Professional Experience

Tell me about a challenging project you delivered. What were the technical hurdles, and how did you overcome them?

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 prioritize your tasks when faced with competing deadlines from multiple business units?

Medium · Behavioral & Professional Experience

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 a situation where you made a mistake in production. How did you handle the immediate fallout, and wha

Medium · Behavioral & Professional Experience

Describe a situation where you made a mistake in production. How did you handle the immediate fallout, and what did you do to prevent it from happening again?

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?