cswork / libraryOpen practice workspace

Interview guides · Internet Brands

Internet Brands Software Engineer Interview Guide

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

The 60-second brief

A Software Engineer at Internet Brands plays a critical role in powering some of the web's most heavily trafficked vertical websites. Operating across diverse sectors such as health, legal, automotive, and home and travel, the engineering team builds, optimizes, and scales platforms that serve millions of unique visitors daily. The solutions you develop directly impact user acquisition, content delivery, and transaction processing across highly recognized digital portfolios. In this role, you are not just writing code; you are managing the performance, stability, and feature sets of high-volume web properties. The work involves a blend of modernizing legacy systems, implementing robust APIs, and optimizing database queries to handle massive concurrent traffic.

This guide is scoped to a Software Engineer candidate at Internet Brands.

Focus areas

  • Coding assessments
  • PHP
  • Algorithmic problem solving

The Internet Brands interview process

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

Phone Screening

Initial call with an internal recruiter to discuss your background, career goals, and compensation expectations.

What to demonstrate

  • Initial call with an internal recruiter to discuss your background, career goals, and compensation expectations
  • Depth in Coding assessments

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.

Online Technical Assessment

Timed assessment featuring coding challenges and multiple-choice questions on web fundamentals and language-specific concepts.

What to demonstrate

  • Timed assessment featuring coding challenges and multiple-choice questions on web fundamentals and language-specific concepts
  • Depth in Coding assessments

How to prepare

  • Answer aloud and timed: Given an array of integers, write a method to count the number of occurrences of a target number.
  • Answer aloud and timed: How would you find the first non-repeating character in a given string?

Technical Interviews

One or more virtual interviews conducted by senior engineers or team leads involving live coding and system design discussions.

What to demonstrate

  • One or more virtual interviews conducted by senior engineers or team leads involving live coding and system design discussions
  • Depth in Coding assessments

How to prepare

  • Answer aloud and timed: Write a program to merge two sorted arrays into a single, sorted array.
  • Answer aloud and timed: Explain the core principles of Object-Oriented Programming (OOP) and how you apply them to write maintainable code.

Comprehensive Interview Loop

Final stage where you meet with engineering managers, directors, or executive leadership to assess behavioral alignment and strategic fit.

What to demonstrate

  • Final stage where you meet with engineering managers, directors, or executive leadership to assess behavioral alignment and strategic fit
  • Depth in Coding assessments

How to prepare

  • Answer aloud and timed: What is the difference between an abstract class and an interface, and when would you use each?
  • Answer aloud and timed: Describe the architecture of a RESTful API and how you handle versioning and error states.

Where candidates lose points

Clarify the Role Stack Early

Because Internet Brands manages a massive portfolio of diverse websites, different teams use vastly different technology stacks. Ensure you know whether your target team focuses on enterprise Java, PHP/WordPress, or modern JavaScript frameworks so you can tailor your preparation accordingly.

Practice Whiteboard and Paper Coding

Some teams still conduct technical rounds where you are asked to write code on a whiteboard, a piece of paper, or a plain text document without syntax highlighting or auto-complete. Practice writing standard algorithms by hand to build confidence.

Prepare Your Project Deep Dives

Be ready to walk through a complex project from your past experience in detail. You should be able to explain the business problem, the technical architecture you chose, the trade-offs you made, and the ultimate impact of your work.

Questions & practice

Write a function to reverse a linked list in-place using your preferred programming language.

Medium · Coding and Algorithm Fundamentals

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?

Implement an algorithm to reverse a string word-by-word (e.g., "the sky is blue" becomes "blue is sky the").

Medium · Coding and Algorithm Fundamentals

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, write a method to count the number of occurrences of a target number.

Medium · Coding and Algorithm Fundamentals

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 find the first non-repeating character in a given string?

Medium · Coding and Algorithm Fundamentals

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 merge two sorted arrays into a single, sorted array.

Medium · Coding and Algorithm Fundamentals

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 box model in CSS and how asynchronous JavaScript operations interact with the DOM.

Medium · Web Technologies & Platform-Specific Con

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 optimize slow-running SQL queries in a relational database like MySQL?

Medium · Object-Oriented Programming & Web Archit

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?

Keep soft-deleted accounts from blocking re-registration

Easy · soft delete · unique constraints · engine differences

app_user holds user_id, tenant_id, email CITEXT, password_hash (NULL for SSO principals), email_verified_at, auth_version, status ('invited','active','suspended','deactivated'), created_at, updated_at, deleted_at. Two live accounts for one address inside a tenant must be impossible, but an address freed by a soft delete must be reusable, and the same tenant may delete and re-register it repeatedly. Write the uniqueness DDL for PostgreSQL 16, then the equivalent for MySQL 8 where partial indexes do not exist, and say what each permits once three deleted rows already hold that address.

Approach

  1. Start from what is actually unique: not (tenant_id, email), but (tenant_id, email) among live rows. PostgreSQL says that directly — CREATE UNIQUE INDEX app_user_live_email ON app_user (tenant_id, email) WHERE deleted_at IS NULL. A full constraint over the same two columns burns the address permanently the first time someone deletes an account.
  2. Keep case-insensitivity in the type or the index, never in the application: CITEXT as given, or UNIQUE (tenant_id, lower(email)) as an expression index where the extension is unavailable. A case-sensitive unique column is exactly how two accounts for one human appear.
  3. For MySQL 8 the predicate has to move inside the key: add a discriminator column that is a constant 0 while the row is live and is set to user_id on delete, with UNIQUE (tenant_id, email, deleted_marker). Live rows share the constant and still collide; deleted rows differ from each other and stop colliding.
  4. State the NULL variant and its dependency: leaving the marker NULL for deleted rows also works, because a unique index treats NULLs as distinct — true in MySQL, and true in PostgreSQL only under the default NULLS DISTINCT, which PostgreSQL 15 lets you reverse. Check the polarity against the three existing deleted rows: constant-on-live is what preserves the collision you want, and reversing it silently admits duplicate live accounts.

Follow-up

  • A deleted account re-registers with the same address the next day. Do the old resource rows follow the new user_id, and how does the API keep the two principals apart?
  • How do you honour an erasure request while resource_revision.actor_user_id still references this table?

Explain the core principles of Object-Oriented Programming (OOP) and how you apply them to write maintainable

Medium · Object-Oriented Programming & Web Archit

Explain the core principles of Object-Oriented Programming (OOP) and how you apply them to write maintainable code.

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 an abstract class and an interface, and when would you use each?

Medium · Object-Oriented Programming & Web Archit

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 architecture of a RESTful API and how you handle versioning and error states.

Medium · Object-Oriented Programming & Web Archit

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?

Explain how sessions and cookies work in a distributed web environment.

Medium · Object-Oriented Programming & Web Archit

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 lifecycle of a request in a PHP framework or a WordPress environment.

Medium · Web Technologies & Platform-Specific Con

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 performance implications of using complex plugins or custom theme queries in WordPress, and how d

Medium · Web Technologies & Platform-Specific Con

What are the performance implications of using complex plugins or custom theme queries in WordPress, and how do you mitigate 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?

How would you implement a secure user authentication system from scratch?

Medium · Web Technologies & Platform-Specific Con

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?

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 Internet Brands candidates report.

Day 1 — Map the Internet Brands loop

  • Write out the reported sequence: Phone Screening, Online Technical Assessment, Technical Interviews, Comprehensive Interview Loop.
  • 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 Coding assessments

  • Spend the session on Coding assessments, which Internet Brands candidates report being tested on.
  • Write one worked example in Coding assessments and time yourself on it.

Deliverable: One timed worked example in Coding assessments.

Day 3 — Work PHP

  • Spend the session on PHP, which Internet Brands candidates report being tested on.
  • Write one worked example in PHP and time yourself on it.

Deliverable: One timed worked example in PHP.

Day 4 — Work Algorithmic problem solving

  • Spend the session on Algorithmic problem solving, which Internet Brands candidates report being tested on.
  • Write one worked example in Algorithmic problem solving and time yourself on it.

Deliverable: One timed worked example in Algorithmic problem solving.

Day 5 — Answer out loud: Coding and Algorithm Fundamentals

  • Answer aloud, timed: Write a function to reverse a linked list in-place using your preferred programming language.
  • Answer aloud, timed: Implement an algorithm to reverse a string word-by-word (e.g., "the sky is blue" becomes "blue is sky the").

Deliverable: Spoken answers to 2 reported Coding and Algorithm Fundamentals question(s), under time.

Day 6 — Answer out loud: Object-Oriented Programming & Web Architecture

  • Answer aloud, timed: Explain the core principles of Object-Oriented Programming (OOP) and how you apply them to write maintainable code.
  • Answer aloud, timed: What is the difference between an abstract class and an interface, and when would you use each?

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

Day 7 — Answer out loud: Web Technologies & Platform-Specific Concepts

  • Answer aloud, timed: How do you handle dependency injection in a Java environment?
  • Answer aloud, timed: Describe the lifecycle of a request in a PHP framework or a WordPress environment.

Deliverable: Spoken answers to 2 reported Web Technologies & Platform-Specific Concepts question(s), under time.

Behavioural preparation

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

How do you handle dependency injection in a Java environment?

Medium · Web Technologies & Platform-Specific Con

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 time when you had to work on a project with vague requirements. How did you proceed?

Medium · Behavioral & Situational Scenarios

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 technical bug you encountered in production and how you went about resolving it.

Medium · Behavioral & Situational Scenarios

Approach

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

Follow-up

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

How do you handle situations where a project deadline is fast approaching but the scope has suddenly changed?

Medium · Behavioral & Situational Scenarios

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?

Walk me through a project from your resume that you are particularly proud of, detailing your specific contrib

Medium · Behavioral & Situational Scenarios

Walk me through a project from your resume that you are particularly proud of, detailing your specific contributions.

Approach

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

Follow-up

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

How do you manage technical disagreements with other developers or system architects?

Medium · Behavioral & Situational Scenarios

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?