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Samba TV Software Engineer Interview Guide

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

The 60-second brief

A Software Engineer at Samba TV plays a pivotal role in shaping the future of real-time television analytics and multi-screen advertising. The engineering team builds and maintains the core technology that powers Automatic Content Recognition (ACR), which is embedded in millions of Smart TVs globally. By joining this team, you are responsible for processing massive, high-throughput data streams, converting raw viewing telemetry into actionable, privacy-compliant insights for broadcasters, advertisers, and content creators. The impact of this position is felt across the entire media ecosystem. You will work on complex backend architectures, high-performance data pipelines, and low-latency APIs that must scale seamlessly to handle billions of daily data points.

This guide is scoped to a Software Engineer candidate at Samba TV.

Focus areas

  • System Design
  • Algorithms
  • Coding Interviews (Problem Solving)

The Samba TV interview process

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

Recruiter Phone Screen

Initial call to discuss your background, career goals, and interest in Samba TV.

What to demonstrate

  • Initial call to discuss your background, career goals, and interest in Samba TV
  • Depth in System Design

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 Screening

Includes an online coding assessment and a technical phone interview with a hiring manager.

What to demonstrate

  • Includes an online coding assessment and a technical phone interview with a hiring manager
  • Depth in System Design

How to prepare

  • Answer aloud and timed: How would you efficiently merge multiple sorted streams of viewing data while minimizing memory usage?
  • Answer aloud and timed: Solve a classic string manipulation or sliding window problem on CoderPad, demonstrating how you handle boundary conditions and invalid inputs.

On-site Interview

Comprehensive interview consisting of five to six sessions covering various technical topics.

What to demonstrate

  • Comprehensive interview consisting of five to six sessions covering various technical topics
  • Depth in System Design

How to prepare

  • Answer aloud and timed: How would you design a high-throughput ingestion pipeline capable of processing millions of concurrent telemetry events from Smart TVs?
  • Answer aloud and timed: Explain how you would architect a real-time querying system for media analytics that supports low-latency dashboard reads.

Where candidates lose points

Do Not Pause Your Online Assessments

If you receive an automated coding test, ensure you complete it in one sitting. The system is designed to track continuous progress, and pausing or closing the test can result in automatic disqualification.

Some candidates have reported receiving automated take-home assignments or coding tests without initial human contact

Treat these tests with high priority and professionalism, as they are the primary gatekeeper to speaking with an engineer or hiring manager.

Drive the System Design Conversation

During the system design round, do not wait for the interviewer to tell you what to do. Take initiative, ask clarifying questions about scale and constraints, state your assumptions clearly, and draw a high-level architecture before diving into specific components.

Questions & practice

Implement a function to find the longest contiguous subarray that meets a specific telemetry pattern, optimizi

Medium · Algorithms and Data Structures

Implement a function to find the longest contiguous subarray that meets a specific telemetry pattern, optimizing for $O(N)$ time complexity.

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 efficiently merge multiple sorted streams of viewing data while minimizing memory usage?

Medium · Algorithms and Data Structures

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?

Solve a classic string manipulation or sliding window problem on CoderPad, demonstrating how you handle bounda

Medium · Algorithms and Data Structures

Solve a classic string manipulation or sliding window problem on CoderPad, demonstrating how you handle boundary conditions and invalid inputs.

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 how the Linux kernel handles process scheduling and memory management under heavy I/O loads.

Medium · Systems and Networking

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 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?

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?

Given a stream of data packets from a Smart TV client, how would you design an algorithm to detect and filter

Medium · Algorithms and Data Structures

Given a stream of data packets from a Smart TV client, how would you design an algorithm to detect and filter out duplicate events in real-time?

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 high-throughput ingestion pipeline capable of processing millions of concurrent telemet

Medium · System Design and Architecture

How would you design a high-throughput ingestion pipeline capable of processing millions of concurrent telemetry events from Smart TVs?

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 how you would architect a real-time querying system for media analytics that supports low-latency dash

Medium · System Design and Architecture

Explain how you would architect a real-time querying system for media analytics that supports low-latency dashboard reads.

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 software architecture and communication protocols you would use to implement Android IPC (Inter-P

Medium · System Design and Architecture

Describe the software architecture and communication protocols you would use to implement Android IPC (Inter-Process Communication) for a TV-embedded application.

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 data partitioning, replication, and consistency in a globally distributed database system?

Medium · System Design and 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 difference between TCP and UDP, and discuss which protocol you would choose for streaming TV viewi

Medium · Systems and Networking

Explain the difference between TCP and UDP, and discuss which protocol you would choose for streaming TV viewing telemetry.

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 me through the lifecycle of a system call in a Unix-like operating system.

Medium · Systems and Networking

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 network latency issue between an embedded client and your backend ingestion servers?

Medium · Systems and Networking

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?

Describe a situation where you had to debug a critical production outage under tight time constraints. How did

Medium · Behavioral and Culture Fit

Describe a situation where you had to debug a critical production outage under tight time constraints. How did you identify the root cause?

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 Samba TV candidates report.

Day 1 — Map the Samba TV loop

  • Write out the reported sequence: Recruiter Phone Screen, Technical Screening, On-site Interview.
  • 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 System Design

  • Spend the session on System Design, which Samba TV candidates report being tested on.
  • Write one worked example in System Design and time yourself on it.

Deliverable: One timed worked example in System Design.

Day 3 — Work Algorithms

  • Spend the session on Algorithms, which Samba TV candidates report being tested on.
  • Write one worked example in Algorithms and time yourself on it.

Deliverable: One timed worked example in Algorithms.

Day 4 — Work Coding Interviews (Problem Solving)

  • Spend the session on Coding Interviews (Problem Solving), which Samba TV candidates report being tested on.
  • Write one worked example in Coding Interviews (Problem Solving) and time yourself on it.

Deliverable: One timed worked example in Coding Interviews (Problem Solving).

Day 5 — Answer out loud: Algorithms and Data Structures

  • Answer aloud, timed: Given a stream of data packets from a Smart TV client, how would you design an algorithm to detect and filter out duplicate events in real-time?
  • Answer aloud, timed: Implement a function to find the longest contiguous subarray that meets a specific telemetry pattern, optimizing for $O(N)$ time complexity.

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

Day 6 — Answer out loud: System Design and Architecture

  • Answer aloud, timed: How would you design a high-throughput ingestion pipeline capable of processing millions of concurrent telemetry events from Smart TVs?
  • Answer aloud, timed: Explain how you would architect a real-time querying system for media analytics that supports low-latency dashboard reads.

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

Day 7 — Answer out loud: Systems and Networking

  • Answer aloud, timed: Explain the difference between TCP and UDP, and discuss which protocol you would choose for streaming TV viewing telemetry.
  • Answer aloud, timed: Describe how the Linux kernel handles process scheduling and memory management under heavy I/O loads.

Deliverable: Spoken answers to 2 reported Systems and Networking question(s), under time.

Behavioural preparation

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

Tell me about a time you had to resolve a highly challenging technical disagreement with a senior team member

Medium · Behavioral and Culture Fit

Tell me about a time you had to resolve a highly challenging technical disagreement with a senior team member or stakeholder.

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?

Why are you interested in working at Samba TV, and how do you see your background in systems or data engineeri

Medium · Behavioral and Culture Fit

Why are you interested in working at Samba TV, and how do you see your background in systems or data engineering contributing to our mission?

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 complex project you owned from inception to delivery. What were the key trade-offs you made du

Medium · Behavioral and Culture Fit

Tell me about a complex project you owned from inception to delivery. What were the key trade-offs you made during the design phase?

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?