As a Software Engineer at Eos, you will play a pivotal role in developing and maintaining software that supports our mission to deliver innovative solutions in the technology landscape. This position is critical not only for the functionality of our products but also for enhancing user experience and driving business growth. You will be involved in designing scalable systems that support our diverse range of offerings, from cloud services to data analytics, ensuring that our technology remains at the forefront of the industry. The impact of your work will resonate across various teams, including product management, user experience, and operations, as you collaborate to tackle complex challenges and create robust solutions. You will contribute to projects that span multiple domains, allowing you to engage with advanced technologies and methodologies. The role is intellectually rewarding and offers opportunities for personal and professional growth within a dynamic and supportive environment.
HR Screening
reportedInitial screening by HR to assess basic qualifications and fit.
What to demonstrate
- Initial screening by HR to assess basic qualifications and fit
- Depth in HR phone screening
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 Assessments
reportedCandidates undergo technical challenges to evaluate their skills.
What to demonstrate
- Candidates undergo technical challenges to evaluate their skills
- Depth in HR phone screening
How to prepare
- Answer aloud and timed: Describe a challenging technical problem you faced and how you resolved it.
- Answer aloud and timed: What tools or frameworks do you prefer for version control and why?
Team Interviews
reportedInterviews with team members or leadership to assess collaboration and cultural fit.
What to demonstrate
- Interviews with team members or leadership to assess collaboration and cultural fit
- Depth in HR phone screening
How to prepare
- Answer aloud and timed: How do you ensure the quality of your code?
- Answer aloud and timed: Tell me about a time when you had to work under tight deadlines. How did you manage your time?
PracHub editorial advice for the preparation topics above.
Practice coding challenges
Brush up on common coding problems and algorithms to prepare for technical assessments.
Be ready to discuss your projects
Have examples of your work ready to share, focusing on your contributions and the impact of your projects.
Research Eos
Familiarize yourself with the company’s products, culture, and values to demonstrate your interest during interviews.
Ask insightful questions
Prepare thoughtful questions for your interviewers to show your engagement and curiosity about the role and company.
Choose a category, try a prompt, then open its approach, worked solution or follow-up when you need it.
Solve a problem using a specific algorithm (e.g., sorting, searching).
Solve a problem using a specific algorithm (e.g., sorting, searching).
Approach
- Restate the input: its shape, its size, and what is guaranteed about it.
- Name the brute-force solution and its complexity before improving on it.
- Choose the data structure from the access pattern, not from familiarity.
- 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 optimize a piece of code for performance?
How would you optimize a piece of code for performance?
Approach
- Restate the input: its shape, its size, and what is guaranteed about it.
- Name the brute-force solution and its complexity before improving on it.
- Choose the data structure from the access pattern, not from familiarity.
- 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 differences between synchronous and asynchronous programming.
Explain the differences between synchronous and asynchronous programming.
Approach
- Say what the runtime actually does before reasoning about the code.
- Name what is shared across threads and what owns each piece of state.
- Identify the window where an invariant is briefly untrue.
- 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?
Write a function to reverse a linked list.
Write a function to reverse a linked list.
Approach
- Restate the input: its shape, its size, and what is guaranteed about it.
- Name the brute-force solution and its complexity before improving on it.
- Choose the data structure from the access pattern, not from familiarity.
- 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 tests for your code?
How do you approach writing tests for your code?
Approach
- Restate the input: its shape, its size, and what is guaranteed about it.
- Name the brute-force solution and its complexity before improving on it.
- Choose the data structure from the access pattern, not from familiarity.
- 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?
Replace offset paging on the resource feed with keyset
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
- 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.
- 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.
- 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.
- 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?
Keep soft-deleted accounts from blocking re-registration
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
- 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.
- 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.
- 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.
- 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?
What programming languages are you most comfortable with, and why?
What programming languages are you most comfortable with, and why?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- Work from the requirement backwards to the design.
Follow-up
- What assumption would you test first?
- How would you know your answer was wrong?
Can you explain the concept of object-oriented programming and its principles?
Can you explain the concept of object-oriented programming and its principles?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- 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 a challenging technical problem you faced and how you resolved it.
Describe a challenging technical problem you faced and how you resolved it.
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- 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 tools or frameworks do you prefer for version control and why?
What tools or frameworks do you prefer for version control and why?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- 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 do you ensure the quality of your code?
How do you ensure the quality of your code?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- 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 approach designing a new feature for our existing product?
How would you approach designing a new feature for our existing product?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- 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 do you evaluate the trade-offs between different technical solutions?
How do you evaluate the trade-offs between different technical solutions?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- Work from the requirement backwards to the design.
Follow-up
- What assumption would you test first?
- How would you know your answer was wrong?
Provide an example of how you have improved a process in your last job.
Provide an example of how you have improved a process in your last job.
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- 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 strategies do you employ to keep up with industry trends and advancements?
What strategies do you employ to keep up with industry trends and advancements?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- 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 your process for debugging a complex issue in a software application.
Describe your process for debugging a complex issue in a software application.
Approach
- Establish what changed and when, before forming any theory.
- Pick a bisection that eliminates candidates whichever way it turns out.
- Check the instrumentation before believing the symptom.
- 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?
Built from the rounds and topics Eos candidates report.
Prepare, practise & reflect
One practical outcome each day. Spend longer where you need it.
0 / 7 done01Map the Eos loop
- Write out the reported sequence: HR Screening, Technical Assessments, Team Interviews.
- 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.
02Work HR phone screening
- Spend the session on HR phone screening, which Eos candidates report being tested on.
- Write one worked example in HR phone screening and time yourself on it.
Deliverable: One timed worked example in HR phone screening.
03Work Technical capabilities assessment
- Spend the session on Technical capabilities assessment, which Eos candidates report being tested on.
- Write one worked example in Technical capabilities assessment and time yourself on it.
Deliverable: One timed worked example in Technical capabilities assessment.
04Work Interview process structuring
- Spend the session on Interview process structuring, which Eos candidates report being tested on.
- Write one worked example in Interview process structuring and time yourself on it.
Deliverable: One timed worked example in Interview process structuring.
05Answer out loud: Technical / Domain Questions
- Answer aloud, timed: What programming languages are you most comfortable with, and why?
- Answer aloud, timed: Can you explain the concept of object-oriented programming and its principles?
Deliverable: Spoken answers to 2 reported Technical / Domain Questions question(s), under time.
06Answer out loud: Behavioral / Leadership
- Answer aloud, timed: Tell me about a time when you had to work under tight deadlines. How did you manage your time?
- Answer aloud, timed: How do you handle conflict within a team?
Deliverable: Spoken answers to 2 reported Behavioral / Leadership question(s), under time.
07Answer out loud: Problem-Solving / Case Studies
- Answer aloud, timed: Describe your process for debugging a complex issue in a software application.
- Answer aloud, timed: How would you approach designing a new feature for our existing product?
Deliverable: Spoken answers to 2 reported Problem-Solving / Case Studies question(s), under time.
Expand any day for tasks and deliverables. Your progress is saved on this device.
Behavioural rounds judge the decision you made and what it cost.
Tell me about a time when you had to work under tight deadlines. How did you manage your time?
Tell me about a time when you had to work under tight deadlines. How did you manage your time?
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- 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 conflict within a team?
How do you handle conflict within a team?
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- 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?
Can you describe a situation where you took the lead on a project?
Can you describe a situation where you took the lead on a project?
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- 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 motivates you to succeed in your work?
What motivates you to succeed in your work?
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- 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 managing multiple projects?
How do you prioritize tasks when managing multiple projects?
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- 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?
- 01
Tell me about a time when you had to work under tight deadlines. How did you manage your time?
- 02
How do you handle conflict within a team?
- 03
Can you describe a situation where you took the lead on a project?
- 04
What motivates you to succeed in your work?
How difficult are the interviews at Eos?
The interviews are generally challenging, focusing on both technical skills and cultural fit. Candidates should allocate ample preparation time to ensure they can effectively showcase their abilities.
Eos Software Engineer candidate reports ↗What differentiates successful candidates at Eos?
Successful candidates demonstrate a strong technical foundation, problem-solving skills, and the ability to collaborate effectively with others. They also align closely with the company's values and mission.
Eos Software Engineer candidate reports ↗How long does the interview process typically take?
The timeline from the initial screening to the final offer can vary but generally spans several weeks. Candidates should be prepared for multiple rounds of interviews during this period.
Eos Software Engineer candidate reports ↗What is the company culture like at Eos?
Eos promotes a collaborative and innovative culture, encouraging employees to share ideas and take ownership of their work. Teamwork and open communication are highly valued.
Eos Software Engineer candidate reports ↗Are there opportunities for remote work?
While many positions offer flexibility, specific arrangements will depend on the team and role. Candidates should inquire about remote work policies during the interview.
Eos Software Engineer candidate reports ↗What topics does Eos test in interviews?
Eos interviews most often cover Candidate Experience Management, Sales & Marketing Systems Administration, Project Management, Pre-Sales Engineering, and Solutions Engineering (Pre-Sales). The exact emphasis depends on the specific role you apply for.
Eos Software Engineer candidate reports ↗Sources & methodology 3 sources ↗
No official company page is cited. Rounds and questions come from candidate reports and PracHub editorial material; each source shows the date it was read.
- 01Eos Software Engineer candidate reports ↗
Company-reported rounds, questions and FAQ.
Candidate reports · Accessed 2026-09-22 - 02PracHub Software Engineer practice ↗
PracHub practice material, not company-reported.
PracHub page · Accessed 2026-09-22 - 03PracHub preparation framework ↗
PracHub preparation guidance.
PracHub page · Accessed 2026-09-22
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