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S&P Global Energy Software Engineer Interview Guide

S&P Global Energy Software Engineer interview guide: reported rounds, questions and how candidates describe the process.

The 60-second brief

As a Software Engineer at S&P Global Energy, you sit at the intersection of complex data, global markets, and critical infrastructure. You are responsible for building and maintaining the high-performance platforms that provide energy market participants with the transparency and insights they need to make mission-critical decisions. Your work directly impacts how energy is tracked, traded, and analyzed on a global scale. The role involves navigating significant technical challenges, ranging from processing high-volume streaming data to designing resilient microservices architectures. You will collaborate with cross-functional teams to modernize legacy systems, optimize database performance, and ensure our software solutions are scalable and secure.

This guide is scoped to a Software Engineer candidate at S&P Global Energy.

Focus areas

  • Data Structures & Algorithms (DSA)
  • Java
  • Spring Boot

The S&P Global Energy interview process

S&P Global Energy candidates report 3 rounds over 3-5 weeks. The stages below are what candidates describe, not a published process.

Recruiter Screening

Initial screening call with a recruiter to assess candidate qualifications and fit.

What to demonstrate

  • Initial screening call with a recruiter to assess candidate qualifications and fit
  • Depth in Data Structures & Algorithms (DSA)

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 Deep Dives

Multiple technical interviews focusing on specific skills and problem-solving abilities.

What to demonstrate

  • Multiple technical interviews focusing on specific skills and problem-solving abilities
  • Depth in Data Structures & Algorithms (DSA)

How to prepare

  • Answer aloud and timed: Describe the principles of SOLID design and provide an example of how you have applied them.
  • Answer aloud and timed: Explain the concept of event bubbling and how to manage event propagation in JavaScript.

Managerial Discussion

Final discussion with a manager to evaluate overall fit within the team and company culture.

What to demonstrate

  • Final discussion with a manager to evaluate overall fit within the team and company culture
  • Depth in Data Structures & Algorithms (DSA)

How to prepare

  • Answer aloud and timed: How do you optimize memory usage in a high-concurrency environment?
  • Answer aloud and timed: Given an array, find the largest number or implement a specific sorting algorithm.

Where candidates lose points

Own your resume

Be prepared to discuss every project or skill listed on your resume in detail. If you mention a technology, expect to be asked how it works under the hood.

Think aloud

When solving a coding problem, do not stay silent. Walk the interviewer through your logic so they can see how you approach ambiguity.

Ask meaningful questions

At the end of your interviews, ask about the team’s current technical challenges or how they balance innovation with maintenance. It shows genuine interest.

Be ready for puzzles

Occasionally, interviewers may ask logical puzzles to test your lateral thinking and problem-solving speed.

Research the domain

Understanding the basics of the energy or financial data sector will give you a significant edge in demonstrating your interest in the company's mission.

Questions & practice

How do you optimize memory usage in a high-concurrency environment?

Medium · Technical Foundations & 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?

Given an array, find the largest number or implement a specific sorting algorithm.

Medium · Data Structures, Algorithms & SQL

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 manage database joins and complex filtering for large datasets?

Medium · Data Structures, Algorithms & SQL

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 time and space complexity of your chosen solution for a given problem.

Medium · Data Structures, Algorithms & SQL

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 your strategy for SQL query optimization (e.g., indexing, B-Trees, execution plans).

Medium · Data Structures, Algorithms & SQL

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?

Denormalise tenant onto revisions and backfill it live

Hard · denormalisation · online migration · backfill

resource_revision (revision_id, resource_id, version, actor_user_id, change_kind, patch, request_id, created_at) has 400M rows and no tenant column; tenant_id lives only on resource. Two reads need it: a tenant-scoped audit feed ordered by created_at DESC, and an offboarding purge. Both join back to resource today. Justify adding tenant_id to resource_revision against those two reads, name the anomaly the copy introduces and the constraint that prevents it, then give the ordered migration for a live table taking 1.2k writes/second — the lock each step takes, how the backfill is batched, and where each step stops being reversible. PostgreSQL 16.

Approach

  1. Justify from the access path rather than from taste. Without the column, the audit feed either scans resource_revision by created_at and discards other tenants' rows, or resolves the tenant's resource_ids first and probes with them — both proportional to the tenant's whole history rather than to one page. With (tenant_id, created_at DESC, revision_id DESC) it is a seek that stops at 50 rows, and the purge becomes a ranged delete instead of a join.
  2. Name the cost exactly: a second copy of a fact can disagree with the first. Make the disagreement unwritable rather than documented — add UNIQUE (resource_id, tenant_id) on resource so it can serve as a foreign-key target, then FOREIGN KEY (resource_id, tenant_id) REFERENCES resource (resource_id, tenant_id) on the revision table. A revision can then only ever carry its parent's tenant.
  3. Step one, expand: ALTER TABLE resource_revision ADD COLUMN tenant_id BIGINT NULL, with no default, so it is a catalogue change and no rewrite. It still needs ACCESS EXCLUSIVE for an instant, and that instant queues behind the longest open transaction on the table while every later query queues behind it — set lock_timeout to 2s and retry rather than wait.
  4. Step two, dual-write: deploy the writer that populates tenant_id on every new revision while reads still use the join. Reversible by redeploying the previous build, because nothing reads the column yet.

Follow-up

  • The backfill is half finished and a rollback is required. What state is the table in, and what does the previous build do with a half-populated column?
  • How do you verify the backfill actually finished, given rows are still being inserted while it runs?

Explain the difference between abstract classes and interfaces and when to use each.

Medium · Technical Foundations & 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?

Describe the principles of SOLID design and provide an example of how you have applied them.

Medium · Technical Foundations & Programming

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 event bubbling and how to manage event propagation in JavaScript.

Medium · Technical Foundations & 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 would you design a system to handle millions of records in a UI while maintaining performance?

Medium · System Design & 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?

Explain the role of Message Queues in a microservices architecture.

Medium · System Design & 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 design for high availability and scalability using Cloud (AWS) services?

Medium · System Design & 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?

What is your approach to debugging a slow application after prolonged usage in a production environment?

Medium · System Design & Architecture

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 S&P Global Energy candidates report.

Day 1 — Map the S&P Global Energy loop

  • Write out the reported sequence: Recruiter Screening, Technical Deep Dives, Managerial Discussion.
  • 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 Data Structures & Algorithms (DSA)

  • Spend the session on Data Structures & Algorithms (DSA), which S&P Global Energy 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 3 — Work Java

  • Spend the session on Java, which S&P Global Energy candidates report being tested on.
  • Write one worked example in Java and time yourself on it.

Deliverable: One timed worked example in Java.

Day 4 — Work Spring Boot

  • Spend the session on Spring Boot, which S&P Global Energy 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 5 — Answer out loud: Technical Foundations & Programming

  • Answer aloud, timed: Explain the difference between abstract classes and interfaces and when to use each.
  • Answer aloud, timed: How do you handle multithreading and synchronization in your applications?

Deliverable: Spoken answers to 2 reported Technical Foundations & Programming question(s), under time.

Day 6 — Answer out loud: Data Structures, Algorithms & SQL

  • Answer aloud, timed: Given an array, find the largest number or implement a specific sorting algorithm.
  • Answer aloud, timed: Describe your strategy for SQL query optimization (e.g., indexing, B-Trees, execution plans).

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

Day 7 — Answer out loud: System Design & Architecture

  • Answer aloud, timed: How would you design a system to handle millions of records in a UI while maintaining performance?
  • Answer aloud, timed: Explain the role of Message Queues in a microservices architecture.

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

Behavioural preparation

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

How do you handle multithreading and synchronization in your applications?

Medium · Technical Foundations & Programming

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 caching to improve performance when loading large volumes of data?

Medium · Data Structures, Algorithms & SQL

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 JWT authentication, token storage, and security concerns like XSS?

Medium · System Design & Architecture

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 time you faced a technical disagreement with a team member; how did you resolve it?

Medium · Behavioral & Cultural Fit

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 challenging project you worked on and your specific contributions to its success.

Medium · Behavioral & Cultural Fit

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 tasks when faced with conflicting business objectives?

Medium · Behavioral & Cultural Fit

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?

What do you do when you are stuck on a technical problem for an extended period?

Medium · Behavioral & Cultural Fit

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?

Explain a complex technical concept to a non-technical stakeholder or a six-year-old.

Medium · Behavioral & Cultural Fit

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?