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Programming Software Engineer Interview Guide

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

The 60-second brief

As a Software Engineer at Programming, you serve as a core contributor to the technical infrastructure that drives the company’s diverse range of client solutions. This role is pivotal in bridging the gap between abstract business requirements and scalable, functional code. You will be expected to demonstrate not only deep technical proficiency but also the autonomy to handle projects independently. The work environment at Programming is fast-paced and heavily project-driven. You will often find yourself working on varied tech stacks—ranging from.NET and React to Java, SQL, and mobile-specific frameworks. Because the company often operates as a service provider, your ability to adapt to client-specific requirements while maintaining high engineering standards is what defines your success and impact on the business. ##### Tip The role often involves direct client interaction.

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

Focus areas

  • Data Structures & Algorithms (DSA)
  • Problem Solving & Algorithmic Thinking
  • Coding Interview Practice

The Programming interview process

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

Initial Screening

The process begins with a screening to assess candidate qualifications.

What to demonstrate

  • The process begins with a screening to assess candidate qualifications
  • 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 Evaluations

Candidates undergo rigorous technical evaluations to demonstrate their skills.

What to demonstrate

  • Candidates undergo rigorous technical evaluations to demonstrate their skills
  • Depth in Data Structures & Algorithms (DSA)

How to prepare

  • Answer aloud and timed: Describe the lifecycle of a React component and how you optimize performance.
  • Answer aloud and timed: What are the key differences between SQL joins and when should you use stored procedures?

Client-Facing Discussions

Final discussions with clients to assess fit and project alignment.

What to demonstrate

  • Final discussions with clients to assess fit and project alignment
  • Depth in Data Structures & Algorithms (DSA)

How to prepare

  • Answer aloud and timed: How do you handle asynchronous data fetching in your preferred programming language?
  • Answer aloud and timed: Can you walk me through your logic for solving [a specific coding problem]?

Where candidates lose points

Own your resume

Be prepared to dive deep into every project you have listed. If you mention a technology, expect to be asked about its internals, not just how to use it.

Practice live coding

Since many rounds involve coding over a video call, practice writing clean, readable code in a shared environment without the benefit of a full IDE.

Ask meaningful questions

Use the interview to learn about the team's workflow and the nature of the client relationship. This shows genuine interest and professional maturity.

Stay flexible

Given the nature of project-based work, be prepared for questions that test your adaptability to changing requirements or new technologies.

Questions & practice

Explain the difference between strong and weak references in memory management.

Medium · Technical & Domain Specifics

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?

Can you walk me through your logic for solving [a specific coding problem]?

Medium · Problem Solving & Coding

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 approach writing Unit Tests for a complex business logic module?

Medium · Problem Solving & Coding

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?

What are the key differences between SQL joins and when should you use stored procedures?

Medium · Technical & Domain Specifics

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?

Replace offset paging on the resource feed with keyset

Easy · keyset pagination · composite index · sort order

resource holds resource_id, tenant_id, owner_user_id, title, body_ref, version, status ('draft','active','archived','deleted'), created_at, updated_at, deleted_at, with an index on (tenant_id, status, updated_at DESC, resource_id DESC). The listing endpoint returns active resources for one tenant, newest update first, 50 per page, today with LIMIT 50 OFFSET n. Tenants reach page 400 and rows are created while they read. Write the keyset query, define what the cursor carries and how it is encoded, and say which part of the index each predicate uses. Assume PostgreSQL 16.

Approach

  1. Name the two failures separately. OFFSET 20000 makes the server produce and discard 20,000 rows, so page cost grows with depth rather than with page size. Independently, any write that changes how many rows sort above the offset moves the window between two fetches, and the direction decides which anomaly you get: an insert lands at the head of updated_at DESC and pushes already-returned rows down past the boundary, so they are returned a second time; a delete above the offset, or a row whose updated_at is bumped above the cursor, pulls rows up and one is never returned at all. Nothing in the response reveals either.
  2. Write the seek: WHERE tenant_id = $1 AND status = 'active' AND (updated_at, resource_id) < ($2, $3) ORDER BY updated_at DESC, resource_id DESC LIMIT 50. The row-value comparison is one index range rather than a disjunction, and both columns are NOT NULL, which is what makes that comparison well defined.
  3. Map each predicate onto the index: tenant_id and status are equality on the leading columns, (updated_at, resource_id) is the range, and the ORDER BY matches the index order so no Sort node appears and the scan stops after 50 rows. The DESC in the definition only matters for mixed directions — a plain ascending btree on the same columns is read backwards for this query.
  4. Put both sort columns in the cursor and nothing the client can tamper with into another tenant: base64 of (updated_at, resource_id), validated server-side, with tenant_id taken from the principal.

Follow-up

  • The client asks for 'jump to page 400'. What do you offer instead, and what does the honest version cost?
  • Sort order becomes user-selectable across four columns. How many indexes is that, and which would you refuse to add?

How do you implement Dependency Injection in a Spring Boot or.NET environment?

Medium · Technical & Domain Specifics

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 lifecycle of a React component and how you optimize performance.

Medium · Technical & Domain Specifics

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 debug a memory leak in a production application?

Medium · Problem Solving & Coding

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 Programming candidates report.

Day 1 — Map the Programming loop

  • Write out the reported sequence: Initial Screening, Technical Evaluations, Client-Facing 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 Data Structures & Algorithms (DSA)

  • Spend the session on Data Structures & Algorithms (DSA), which Programming 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 Problem Solving & Algorithmic Thinking

  • Spend the session on Problem Solving & Algorithmic Thinking, which Programming candidates report being tested on.
  • Write one worked example in Problem Solving & Algorithmic Thinking and time yourself on it.

Deliverable: One timed worked example in Problem Solving & Algorithmic Thinking.

Day 4 — Work Coding Interview Practice

  • Spend the session on Coding Interview Practice, which Programming candidates report being tested on.
  • Write one worked example in Coding Interview Practice and time yourself on it.

Deliverable: One timed worked example in Coding Interview Practice.

Day 5 — Answer out loud: Technical & Domain Specifics

  • Answer aloud, timed: Explain the difference between strong and weak references in memory management.
  • Answer aloud, timed: How do you implement Dependency Injection in a Spring Boot or.NET environment?

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

Day 6 — Answer out loud: Problem Solving & Coding

  • Answer aloud, timed: Can you walk me through your logic for solving [a specific coding problem]?
  • Answer aloud, timed: How would you debug a memory leak in a production application?

Deliverable: Spoken answers to 2 reported Problem Solving & Coding question(s), under time.

Day 7 — Answer out loud: Behavioral & Situational

  • Answer aloud, timed: Tell me about yourself and your journey in software development.
  • Answer aloud, timed: How do you manage a situation where you disagree with a client's technical requirement?

Deliverable: Spoken answers to 2 reported Behavioral & Situational question(s), under time.

Behavioural preparation

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

How do you handle asynchronous data fetching in your preferred programming language?

Medium · Technical & Domain Specifics

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 you had to optimize a slow-running database query.

Medium · Problem Solving & Coding

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 yourself and your journey in software development.

Medium · Behavioral & Situational

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 a situation where you disagree with a client's technical requirement?

Medium · Behavioral & Situational

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 project where you had to work independently with minimal supervision.

Medium · Behavioral & Situational

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 tight deadlines while ensuring code quality?

Medium · Behavioral & Situational

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?