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Auterion Software Engineer Interview Guide

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

The 60-second brief

As a Software Engineer at Auterion, you are at the forefront of the robotics and autonomous systems revolution. Auterion is building the leading open-source operating system for enterprise drones and mobile robotics, seamlessly connecting aerial and ground systems to cloud infrastructure. In this role, your work directly impacts the reliability, scalability, and safety of mission-critical platforms used by enterprise and government customers worldwide. You will be tackling complex engineering challenges that bridge the gap between embedded systems, flight control software, and cloud-based fleet management. Whether you are optimizing core OS components, developing robust enterprise solutions, or ensuring seamless data flow between edge devices and the cloud, your contributions will be highly visible.

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

Focus areas

  • C++
  • Multithreading / Concurrency
  • System design (high-level design)

The Auterion interview process

Auterion candidates report 5 rounds over 4-6 weeks. The stages below are what candidates describe, not a published process.

Conversational Screening Call

Initial call with an HR representative to discuss your background, motivations, and alignment with the company’s mission.

What to demonstrate

  • Initial call with an HR representative to discuss your background, motivations, and alignment with the company’s mission
  • Depth in C++

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-Dive Interview

Interview focusing on your resume, domain-specific knowledge, and high-level system design concepts.

What to demonstrate

  • Interview focusing on your resume, domain-specific knowledge, and high-level system design concepts
  • Depth in C++

How to prepare

  • Answer aloud and timed: How do you handle memory management and prevent memory leaks in modern C++?
  • Answer aloud and timed: Describe your experience working with Linux systems and inter-process communication.

Take-Home Programming Assessment

A comprehensive assessment where you demonstrate your coding skills, typically with a 1-to-2-week deadline.

What to demonstrate

  • A comprehensive assessment where you demonstrate your coding skills, typically with a 1-to-2-week deadline
  • Depth in C++

How to prepare

  • Answer aloud and timed: How would you design a thread-safe data queue for real-time telemetry processing?
  • Answer aloud and timed: Walk me through the high-level architecture of your solution. Why did you structure it this way?

Technical Review Session

Discussion with a senior engineer to review your take-home assessment, focusing on architectural choices and optimizations.

What to demonstrate

  • Discussion with a senior engineer to review your take-home assessment
  • Focusing on architectural choices and optimizations

How to prepare

  • Answer aloud and timed: I noticed you used [specific library/approach] here. What were the trade-offs of that decision?
  • Answer aloud and timed: We found a race condition/bug on this specific line. Can you explain why it is happening and how you would fix it?

Onsite or Virtual Loop

Final stage consisting of team-fit interviews and a conversation with engineering leadership.

What to demonstrate

  • Final stage consisting of team-fit interviews and a conversation with engineering leadership
  • Depth in C++

How to prepare

  • Answer aloud and timed: If we needed to scale this application to handle 10x the current data throughput, what would you change in your code?
  • Answer aloud and timed: How would you design a system to securely stream high-definition video from a drone to a cloud server with variable network latency?

Where candidates lose points

Plan Before You Type

The biggest mistake candidates make on the take-home assessment is rushing into implementation. Map out your thread interactions, data structures, and class hierarchies on paper first. A well-planned architecture will naturally lead to cleaner, bug-free code.

Own Your Mistakes

During the technical review, if an interviewer points out a bug in your code, do not get defensive. Acknowledge it, analyze it out loud, and suggest a fix. Engineering at Auterion is collaborative, and showing that you can take feedback constructively is crucial.

Prepare Your References Early

Because the company takes reference checks seriously at the offer stage, reach out to your previous managers and colleagues early in the interview process. Having a list of responsive, supportive references ready will prevent delays in finalizing your contract.

Ask Clarifying Questions

Whether in a live system design discussion or when reviewing the requirements for the take-home test, never make silent assumptions. Asking insightful questions demonstrates maturity and a strong engineering mindset.

Questions & practice

Explain how you would prevent a deadlock in a heavily multithreaded C++ application.

Medium · Domain and Technical Foundations

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 the key differences between a mutex and a semaphore, and when would you use each?

Medium · Domain and Technical Foundations

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 handle memory management and prevent memory leaks in modern C++?

Medium · Domain and Technical Foundations

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?

We found a race condition/bug on this specific line. Can you explain why it is happening and how you would fix

Medium · Take-Home Assessment Review

We found a race condition/bug on this specific line. Can you explain why it is happening and how you would fix it?

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?

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?

Hold a per-tenant active cap against concurrent creates

Hard · write skew · isolation levels · constraints

A tenant on the standard plan may hold at most 50 resources with status='active'. The create handler runs SELECT count(*) FROM resource WHERE tenant_id = $1 AND status = 'active', compares to 50, then inserts. Two creates arrive 3 ms apart on different instances and the tenant lands at 51. Name the anomaly, say whether PostgreSQL 16 READ COMMITTED or REPEATABLE READ prevents it and why, then give an implementation that holds the cap at READ COMMITTED with the exact statements. Finally, say what changes when the cap is 'at most one running export per tenant' on job_run.

Approach

  1. Name it: write skew. The two transactions read an overlapping set and write disjoint rows, so there is no row-level conflict for the engine to detect and each commit is individually legal.
  2. Rule out the levels precisely. READ COMMITTED takes a fresh snapshot per statement and takes no lock on the counted rows, so both see 49. PostgreSQL's REPEATABLE READ is snapshot isolation: it removes non-repeatable reads and phantoms within the snapshot but still admits write skew, because the anomaly is not a re-read of a changed row, it is a read of a set that a concurrent transaction invalidates. Only SERIALIZABLE closes it, by tracking the read dependency and aborting one transaction with SQLSTATE 40001 — a guarantee that exists only if the application re-runs the whole transaction from the read.
  3. Convert the set predicate into a single-row conflict: keep tenant.active_resource_count and run UPDATE tenant SET active_resource_count = active_resource_count + 1 WHERE tenant_id = $1 AND active_resource_count < 50 in the same transaction as the INSERT. Zero affected rows is the cap, returned as 409. The row lock serialises the decision at any isolation level, and contention is bounded to one tenant's row — which is also the fair-scheduling unit, unlike a global counter that would convoy every tenant behind one row.
  4. State the cost you just took on: a counter is a second source of truth that can drift, so every path that changes status must adjust it inside the same transaction, and a periodic reconciliation has to exist, with resource_revision as the authority for what the count should have been.

Follow-up

  • A resource moves from archived back to active. Which statements change, and what breaks if the counter update and the status change land in different transactions?
  • The cap becomes plan-dependent and a plan can change mid-month. Where does the number 50 live, and who reads it?

How would you design a thread-safe data queue for real-time telemetry processing?

Medium · Domain and Technical Foundations

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?

Walk me through the high-level architecture of your solution. Why did you structure it this way?

Medium · Take-Home Assessment Review

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?

I noticed you used [specific library/approach] here. What were the trade-offs of that decision?

Medium · Take-Home Assessment Review

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?

If we needed to scale this application to handle 10x the current data throughput, what would you change in you

Medium · Take-Home Assessment Review

If we needed to scale this application to handle 10x the current data throughput, what would you change in your 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?

How would you design a system to securely stream high-definition video from a drone to a cloud server with var

Medium · System Design and Architecture

How would you design a system to securely stream high-definition video from a drone to a cloud server with variable network latency?

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?

Walk me through the high-level design of a fleet management dashboard that tracks the real-time location and b

Medium · System Design and Architecture

Walk me through the high-level design of a fleet management dashboard that tracks the real-time location and battery status of 1,000 drones.

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?

One log partition stops advancing while the others drain

Easy · poison message · head-of-line blocking · consumer lag

Search results for a subset of tenants are hours stale; the rest are current. The projection consumer reports lag of zero on 15 of 16 partitions and 400,000 on one. Its error rate is flat and its CPU is idle. outbox_event has no pending rows older than a second, so the relay has published everything it holds. Identify the mechanism, give the ordered checks, and state what you do in the first ten minutes versus what you change permanently.

Approach

  1. Read the lag distribution first. A slow consumer lags everywhere; zero on fifteen partitions and 400,000 on one is not throughput. Idle CPU on the stuck partition means the consumer is not advancing its offset at all, which points at one message it cannot get past rather than at a rate problem.
  2. Exonerate the producer before touching the consumer. No pending outbox rows older than a second means the relay published, so the event exists in the log. This separates never sent from sent and never applied, which are different code paths and usually different owners.
  3. Read the message at the stuck offset and the handler's log lines for its event_id. A flat error rate with no progress has two explanations and you must distinguish them: the handler is throwing and the retry loop is swallowing it, or the handler is blocking on something and never returning. Idle CPU with no error lines favours the second.
  4. Mitigate before diagnosing further. Move the offending event to a dead-letter store and commit the offset past it. Adding consumers does nothing here, because a partition is consumed by exactly one member of the group, and the blast radius is every aggregate hashed to that partition, not only the aggregate that produced the bad event.

Follow-up

  • The dead-lettered event carried aggregate_version 7 and the projection had applied 6. What must the replay do differently if 8 and 9 landed in the meantime?
  • How do you show staleness to the user while the partition is behind, given the API already returns the projection's watermark?

Suggested practice checklist

Built from the rounds and topics Auterion candidates report.

Day 1 — Map the Auterion loop

  • Write out the reported sequence: Conversational Screening Call, Technical Deep-Dive Interview, Take-Home Programming Assessment, Technical Review Session, Onsite or Virtual 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 5 reported rounds, with the weakest marked.

Day 2 — Work C++

  • Spend the session on C++, which Auterion candidates report being tested on.
  • Write one worked example in C++ and time yourself on it.

Deliverable: One timed worked example in C++.

Day 3 — Work Multithreading / Concurrency

  • Spend the session on Multithreading / Concurrency, which Auterion candidates report being tested on.
  • Write one worked example in Multithreading / Concurrency and time yourself on it.

Deliverable: One timed worked example in Multithreading / Concurrency.

Day 4 — Work System design (high-level design)

  • Spend the session on System design (high-level design), which Auterion candidates report being tested on.
  • Write one worked example in System design (high-level design) and time yourself on it.

Deliverable: One timed worked example in System design (high-level design).

Day 5 — Answer out loud: Domain and Technical Foundations

  • Answer aloud, timed: Explain how you would prevent a deadlock in a heavily multithreaded C++ application.
  • Answer aloud, timed: What are the key differences between a mutex and a semaphore, and when would you use each?

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

Day 6 — Answer out loud: Take-Home Assessment Review

  • Answer aloud, timed: Walk me through the high-level architecture of your solution. Why did you structure it this way?
  • Answer aloud, timed: I noticed you used [specific library/approach] here. What were the trade-offs of that decision?

Deliverable: Spoken answers to 2 reported Take-Home Assessment Review question(s), under time.

Day 7 — Answer out loud: System Design and Architecture

  • Answer aloud, timed: How would you design a system to securely stream high-definition video from a drone to a cloud server with variable network latency?
  • Answer aloud, timed: Walk me through the high-level design of a fleet management dashboard that tracks the real-time location and battery status of 1,000 drones.

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

Behavioural preparation

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

Describe your experience working with Linux systems and inter-process communication.

Medium · Domain and Technical Foundations

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 data synchronization between an edge device that frequently loses internet connection and a

Medium · System Design and Architecture

How do you handle data synchronization between an edge device that frequently loses internet connection and a central database?

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 joining Auterion, and what specific areas of robotics or open-source software excite

Medium · Behavioral and Motivations

Why are you interested in joining Auterion, and what specific areas of robotics or open-source software excite you most?

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 had to compromise on a technical design due to tight business deadlines.

Medium · Behavioral and Motivations

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 situation where you had to work closely with a QA or testing team to resolve a complex, hard-to-rep

Medium · Behavioral and Motivations

Describe a situation where you had to work closely with a QA or testing team to resolve a complex, hard-to-reproduce bug.

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?

Which team or product area within Auterion do you feel you are best suited for, and why?

Medium · Behavioral and Motivations

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?