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Verisk Software Engineer Interview Guide

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

The 60-second brief

A Software Engineer at Verisk plays a pivotal role in architecting, developing, and maintaining high-performance data analytics platforms. Verisk is a global leader in data analytics and risk assessment, meaning your work directly impacts how major insurance, financial, and energy institutions calculate risk and make critical decisions. Engineers here do not just write code; they build scalable pipelines, design robust database schemas, and develop intuitive web applications that process massive datasets daily. In this role, you will contribute to core products and platforms, such as XactAnalysis or advanced spatial data engines. You will work in a highly collaborative environment alongside data scientists, product managers, and domain experts to turn complex mathematical models into production-ready software.

This guide is scoped to a Software Engineer candidate at Verisk.

Focus areas

  • OOPS / Object-Oriented Programming
  • Data Structures & Algorithms (DSA)
  • SQL (general)

The Verisk interview process

Verisk candidates report 7 rounds over 4-6 weeks. The stages below are what candidates describe, not a published process.

Online Assessment

Dual-section assessment covering quantitative aptitude and technical concepts like Operating Systems, Computer Networks, and DBMS.

What to demonstrate

  • Dual-section assessment covering quantitative aptitude and technical concepts like Operating Systems, Computer Networks, and DBMS
  • Depth in OOPS / Object-Oriented Programming

How to prepare

  • Answer aloud and timed: Explain the four pillars of OOP and provide a real-world analogy (such as a pizza delivery system) for each.
  • Answer aloud and timed: What is the difference between method overloading and method overriding?

Technical Rounds

One or two rounds focusing on coding on paper or a whiteboard, OOP theory, and writing SQL queries.

What to demonstrate

  • One or two rounds focusing on coding on paper or a whiteboard, OOP theory, and writing SQL queries
  • Depth in OOPS / Object-Oriented Programming

How to prepare

  • Answer aloud and timed: In.NET, why was the generic List data structure created when we already had ArrayList?
  • Answer aloud and timed: Explain the differences between virtual methods, abstract methods, and interface implementations.

Recruiter Screen

Initial screening call with the recruiter to discuss the candidate's background and fit for the role.

What to demonstrate

  • Initial screening call with the recruiter to discuss the candidate's background and fit for the role
  • Depth in OOPS / 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.

Coding Assessment

Complete a coding assessment on a platform like HackerRank.

What to demonstrate

  • Complete a coding assessment on a platform like HackerRank
  • Depth in OOPS / Object-Oriented Programming

How to prepare

  • Answer aloud and timed: How do you find duplicate characters in a string, and what is the time complexity of your approach?
  • Answer aloud and timed: Explain the partition step of Merge Sort and write the code to merge two sorted arrays.

Technical Problem

Solve a technical problem over a weekend if the coding assessment is passed.

What to demonstrate

  • Solve a technical problem over a weekend if the coding assessment is passed
  • Depth in OOPS / Object-Oriented Programming

How to prepare

  • Answer aloud and timed: Write a program to print the Fibonacci series using dynamic programming (tabulation method).
  • Answer aloud and timed: Given a sliding window of size $K$, how would you find the maximum element in each window position?

Presentation Round

Present your solution using a PowerPoint deck to a panel of senior developers, explaining pseudocode and design choices.

What to demonstrate

  • Present your solution using a PowerPoint deck to a panel of senior developers, explaining pseudocode and design choices
  • Depth in OOPS / Object-Oriented Programming

How to prepare

  • Answer aloud and timed: Design a database schema for a railway booking system, detailing the tables, primary keys, and foreign key relationships.
  • Answer aloud and timed: Write a SQL query using an inner join and a left join to retrieve data from two tables where some records might be missing.

System Design and Behavioral

Engage in deep-dive system design discussions and behavioral interviews.

What to demonstrate

  • Engage in deep-dive system design discussions and behavioral interviews
  • Depth in OOPS / Object-Oriented Programming

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 system design and behavioral above and write down what you would ask to confirm before it.

Where candidates lose points

Prepare Your Presentation Thoroughly

If your loop includes a take-home presentation, do not just focus on the code. Ensure your slides are structured professionally, explain your design trade-offs clearly, and practice presenting within the allotted time limit.

Do Not Skip the Puzzles

Spend time practicing classic logic puzzles. Interviewers use them to see how you react to unfamiliar problems; they care more about your structured thinking process than whether you get the exact answer immediately.

Know Your Resume Inside Out

Be ready to explain every project, technology, and certification listed on your resume. You will face detailed questions about why you chose specific frameworks or database structures in your past work.

Show Genuine Interest in Verisk's Domain

Spend some time researching what Verisk does. Understanding how they serve the insurance, financial, and risk sectors will allow you to ask thoughtful questions at the end of your interviews.

Questions & practice

Explain the four pillars of OOP and provide a real-world analogy (such as a pizza delivery system) for each.

Medium · Object-Oriented Programming & Language F

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?

What is the difference between method overloading and method overriding?

Medium · Object-Oriented Programming & Language F

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?

In.NET, why was the generic List data structure created when we already had ArrayList?

Medium · Object-Oriented Programming & Language F

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?

Explain the differences between virtual methods, abstract methods, and interface implementations.

Medium · Object-Oriented Programming & Language F

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?

What are decorators in Python, and how do they modify function behavior at runtime?

Medium · Object-Oriented Programming & Language F

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 function to find the first and second maximum elements in an array using a single pass.

Medium · Data Structures & Algorithms (DSA)

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 find duplicate characters in a string, and what is the time complexity of your approach?

Medium · Data Structures & Algorithms (DSA)

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 partition step of Merge Sort and write the code to merge two sorted arrays.

Medium · Data Structures & Algorithms (DSA)

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 program to print the Fibonacci series using dynamic programming (tabulation method).

Medium · Data Structures & Algorithms (DSA)

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 sliding window of size $K$, how would you find the maximum element in each window position?

Medium · Data Structures & Algorithms (DSA)

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 pass-by-value and pass-by-reference using memory diagrams.

Medium · CS Fundamentals & System Concepts

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 SQL query using an inner join and a left join to retrieve data from two tables where some records migh

Medium · SQL & Database Design

Write a SQL query using an inner join and a left join to retrieve data from two tables where some records might be missing.

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?

How do you optimize a slow-running query that involves multiple joins and large datasets?

Medium · SQL & Database Design

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?

Design a database schema for a railway booking system, detailing the tables, primary keys, and foreign key rel

Medium · SQL & Database Design

Design a database schema for a railway booking system, detailing the tables, primary keys, and foreign key relationships.

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?

What is the difference between a nested subquery and a correlated subquery?

Medium · SQL & Database Design

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 stored procedures and discuss when you should use them instead of raw queries.

Medium · SQL & Database Design

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?

Walk through the OSI model layers and explain exactly what happens to a data packet at each layer.

Medium · CS Fundamentals & System Concepts

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 paging in Operating Systems, and how does it prevent external fragmentation?

Medium · CS Fundamentals & System Concepts

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?

Describe the difference between eager loading and lazy loading in Object-Relational Mapping (ORM) frameworks l

Medium · CS Fundamentals & System Concepts

Describe the difference between eager loading and lazy loading in Object-Relational Mapping (ORM) frameworks like Hibernate or Entity Framework.

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 GET request and a POST request in RESTful APIs?

Medium · CS Fundamentals & System Concepts

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?

You have 3 light bulbs in a room and 3 switches outside the room. You can only enter the room once. How do you

Medium · Puzzles & Logical Reasoning

You have 3 light bulbs in a room and 3 switches outside the room. You can only enter the room once. How do you determine which switch controls which bulb?

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?

You have two ropes. Each rope takes exactly 60 minutes to burn from end to end, but they do not burn at a cons

Medium · Puzzles & Logical Reasoning

You have two ropes. Each rope takes exactly 60 minutes to burn from end to end, but they do not burn at a constant rate. How can you measure exactly 45 minutes using these two ropes?

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 an algorithm to detect if a given pattern of shapes is logically consistent?

Medium · Puzzles & Logical Reasoning

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?

Exports duplicate a row range about once a week

Hard · leases · clock skew · idempotency

Roughly once a week an export writes a file containing a duplicated range of rows. The affected job_run rows show attempt = 1, status = succeeded, one started_at, and a lease_owner naming a different host from the one whose logs show the job starting. Leases last 30 seconds and are heartbeated every 10 from inside the handler; lease_expires_at is computed on the worker and compared against the database's now(). Find the mechanism, and give a fix that holds even if you cannot fix the clocks.

Approach

  1. Start from the fact that eliminates the obvious answer. attempt = 1 means no retry was recorded, so this is not a re-run after failure; two workers ran the same row concurrently and the takeover path never touched the counter. lease_owner naming a host other than the one that started the job is the same statement from the other side.
  2. Enumerate the mechanisms that cause a premature takeover, then find the signal that separates them. Either the lease genuinely expired because the heartbeat did not fire, which is what happens when the heartbeat runs on the handler's own thread and the handler makes a long blocking call, or it only appeared expired because two clocks disagree, since lease_expires_at is written from the worker's clock and evaluated against the database's. The discriminator is the distribution: incidents clustered on the longest exports indict the heartbeat, incidents clustered on one host indict skew. Measure both, and measure each host's offset against the database directly.
  3. Read the reclaim query precisely. In PostgreSQL now() is transaction start time, not statement time, so a reclaimer holding a long transaction compares against an older timestamp than expected; clock_timestamp() is the statement-time function. This is worth ruling in or out before you redesign anything, because it changes which rows look expired.
  4. Remove the second clock rather than trying to synchronise it. Issue and extend the lease in the database, with lease_expires_at = now() + interval '30 seconds' in both the claim and the heartbeat, so exactly one clock is ever compared and worker skew stops mattering to this predicate.

Follow-up

  • The displaced worker has already streamed half the file to object storage. What makes that side effect safe to repeat?
  • You now count takeovers. What alert fires on that counter, and at what threshold?

Suggested practice checklist

Built from the rounds and topics Verisk candidates report.

Day 1 — Map the Verisk loop

  • Write out the reported sequence: Online Assessment, Technical Rounds, Recruiter Screen, Coding Assessment, Technical Problem, Presentation 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 7 reported rounds, with the weakest marked.

Day 2 — Work OOPS / Object-Oriented Programming

  • Spend the session on OOPS / Object-Oriented Programming, which Verisk candidates report being tested on.
  • Write one worked example in OOPS / Object-Oriented Programming and time yourself on it.

Deliverable: One timed worked example in OOPS / Object-Oriented Programming.

Day 3 — Work Data Structures & Algorithms (DSA)

  • Spend the session on Data Structures & Algorithms (DSA), which Verisk candidates report being tested on.
  • Write one worked example in Data Structures & Algorithms (DSA) and time yourself on it.

Deliverable: One timed worked example in Data Structures & Algorithms (DSA).

Day 4 — Work SQL (general)

  • Spend the session on SQL (general), which Verisk candidates report being tested on.
  • Write one worked example in SQL (general) and time yourself on it.

Deliverable: One timed worked example in SQL (general).

Day 5 — Answer out loud: Object-Oriented Programming & Language Fundamentals

  • Answer aloud, timed: Explain the four pillars of OOP and provide a real-world analogy (such as a pizza delivery system) for each.
  • Answer aloud, timed: What is the difference between method overloading and method overriding?

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

Day 6 — Answer out loud: Data Structures & Algorithms (DSA)

  • Answer aloud, timed: Write a function to find the first and second maximum elements in an array using a single pass.
  • Answer aloud, timed: How do you find duplicate characters in a string, and what is the time complexity of your approach?

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

Day 7 — Answer out loud: SQL & Database Design

  • Answer aloud, timed: Design a database schema for a railway booking system, detailing the tables, primary keys, and foreign key relationships.
  • Answer aloud, timed: Write a SQL query using an inner join and a left join to retrieve data from two tables where some records might be missing.

Deliverable: Spoken answers to 2 reported SQL & Database Design question(s), under time.

Behavioural preparation

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

Estimate work you have never done and defend the range

Hard · estimation · backfills · expand-contract

You are asked to estimate a change you have never attempted: add a column to a 100-million-row table, populate it, move reads across, and drop the old shape. Give a range with the assumptions that generate it, including batch size, the signal your backfill throttles on, and wall-clock hours, and name the three unknowns that would move the number most. Then describe a real estimate you gave under comparable ignorance: how you expressed its uncertainty, what you committed to, and how wrong you turned out to be.

Approach

  1. Decompose into independently deployable steps before estimating anything: add the column nullable, write both shapes, backfill in batches, verify, move reads, stop writing the old shape, drop it. That is four deploys spread over days, and the calendar estimate is dominated by them rather than by the loop's runtime.
  2. Do the arithmetic aloud for the part that has arithmetic in it: batch size times number of batches times per-batch duration, at a write rate the primary can absorb alongside roughly 1.2k writes per second of production traffic. The loop is throttled by replication lag and lock waits, not by how fast it can issue statements.
  3. Price the schema step by its lock rather than its statement duration. In PostgreSQL an ALTER TABLE taking ACCESS EXCLUSIVE waits for every open transaction on that table while later queries queue behind it, so a millisecond change issued during a thirty-second analytics query stalls that table for thirty seconds. Adding a nullable column with a non-volatile default avoids a rewrite from version 11; a new index wants CREATE INDEX CONCURRENTLY, which cannot run inside a transaction block and leaves an invalid index behind if it fails.
  4. Express the answer as a range whose endpoints each trace to a stated assumption, then name the cheapest experiment that collapses it, which is almost always running one real batch against the real table and multiplying.

Follow-up

  • How do you verify the backfill genuinely finished, given rows written by production traffic while it ran?
  • Where does the backfill resume from after a worker is killed mid-batch, and what makes that resume point trustworthy?

Narrate an outage you owned from page to postmortem

Hard · incident response · blast radius · postmortems

Pick an incident you personally drove, ideally one where writes were affected rather than reads. In six to eight minutes: state the symptom as it first appeared on a dashboard, the blast radius you established before you knew the cause, the mitigation you applied and when, the mechanism you eventually proved, and the follow-up that would prevent a repeat. Bring numbers: error rate, tenants affected, minutes to mitigate, minutes to resolve. If you cannot name what you measured, choose a different incident.

Approach

  1. Open on the signal rather than the cause: which metric at which percentile moved, on which service, at what time, so the listener follows the same evidence you had rather than a conclusion you already reached.
  2. Separate mitigation from diagnosis out loud. State what you did to stop the bleeding (flag off, shed traffic, drain a lease, roll back a deploy) and say plainly that you did it before the mechanism was known, because those are two jobs with different deadlines.
  3. Establish blast radius in countable terms: how many tenants, how many writes, and crucially whether the effect was loss or only delay. An append-only revision table or a pending outbox row means the change survived and the projection was merely behind, which is a repair rather than a data-loss incident.
  4. Prove the mechanism instead of asserting it. Name the trace span that grew, the plan that flipped to a sequential scan, the lease that expired, plus one alternative you ruled out and the signal that stayed flat while you ruled it out.

Follow-up

  • What would you do differently in the first five minutes, given the same dashboard and no more information?
  • Which follow-up action did you deliberately not take, and why was dropping it the right call?

Reverse your own decision and price the reversal

Medium · reversibility · measurement · migrations

Describe a technical decision you made and later reversed. Pick one that cost something: a service you split and merged back, a cache you added and removed, an index you created that pushed the planner onto a worse plan, a projection you rebuilt from scratch. State what you believed when you decided, the measurement that changed your mind, how long the wrong version ran in production, and what the reversal cost in migrations, dual writes, and a deprecation window for callers you did not own.

Approach

  1. State the original rationale without irony, in the version you would still defend given what was known then. If it is not defensible, the story is about carelessness rather than judgement, and a different example serves you better.
  2. Give the measurement that moved with a before and after: the p99 that did not improve, the cache hit rate that sat at 40%, the plan that flipped to a sequential scan once the table passed a size you can name.
  3. Cost the reversal in steps, not adjectives: expand-and-contract deploys, the dual-write window, the callers who had to be notified, the rows already written in the wrong shape that had to be backfilled or abandoned.
  4. Distinguish reversal from rewrite by naming what you kept. Most good reversals preserve the schema or the interface and undo one decision inside it, which is also why they were affordable.

Follow-up

  • What in that decision was irreversible, and did you know it was irreversible when you made it?
  • How did you tell the people who had already built on top of the original decision?