A Software Engineer at Ness Digital Engineering plays a crucial role in developing innovative solutions that drive business success and enhance user experiences. This position is vital to the company, as it bridges the gap between technical capabilities and client needs, ensuring that products not only meet but exceed expectations. As a Software Engineer, you will contribute to a diverse range of projects that span various industries, tackling complex challenges and creating scalable systems that impact thousands of users. The role involves a mix of coding, problem-solving, and collaboration, requiring you to work closely with multidisciplinary teams. You will be involved in designing, implementing, and maintaining software applications across various domains, such as cloud computing, data analytics, and enterprise solutions. This dynamic environment offers the opportunity to work on cutting-edge technologies and methodologies, making it a rewarding career path for those who thrive on creativity and technical excellence. Expect your work to influence projects that are strategic to our clients and impactful in the marketplace. As a, you will not only write code but also shape the future of technology solutions that drive business innovation. Software Engineer
Initial Screening
reportedAssess your qualifications and fit for the role.
What to demonstrate
- Assess your qualifications and fit for the role
- Depth in Java
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 Interviews
reportedFocus on core skills and problem-solving abilities.
What to demonstrate
- Focus on core skills and problem-solving abilities
- Depth in Java
How to prepare
- Answer aloud and timed: Describe how Spring Boot simplifies the development of Java applications.
- Answer aloud and timed: What are the advantages of using microservices architecture?
Managerial Discussions
reportedEvaluate your leadership potential and fit within the team.
What to demonstrate
- Evaluate your leadership potential and fit within the team
- Depth in Java
How to prepare
- Answer aloud and timed: How do you handle exceptions in your code?
- Answer aloud and timed: How would you optimize a slow-running SQL query?
Final HR Discussions
reportedDiscuss expectations, salary negotiations, and onboarding process.
What to demonstrate
- Discuss expectations, salary negotiations, and onboarding process
- Depth in Java
How to prepare
- Answer aloud and timed: Describe a time when you faced a technical challenge. How did you resolve it?
- Answer aloud and timed: Provide a solution for a given problem using data structures. What considerations did you take into account?
PracHub editorial advice for the preparation topics above.
Research the Company
Understand Ness Digital Engineering’s mission, values, and recent projects. This knowledge will help you align your answers with the company's goals.
Practice Coding
Regularly solve coding challenges on platforms like LeetCode or HackerRank to sharpen your problem-solving skills.
Prepare Real-World Examples
Be ready to discuss your past experiences, focusing on challenges faced, solutions implemented, and outcomes achieved.
Ask Questions
Prepare thoughtful questions for your interviewers that reflect your interest in the role and the company.
Choose a category, try a prompt, then open its approach, worked solution or follow-up when you need it.
Write a function to remove duplicates from an array.
Write a function to remove duplicates from an array.
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?
Implement a sorting algorithm from scratch and explain your reasoning.
Implement a sorting algorithm from scratch and explain your reasoning.
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?
Find overlapping job attempts and peak concurrency from lease records
A day of job_run history yields about 50,000,000 attempt records: (job_run_id, job_type, attempt, started_at, finished_at which is NULL when the worker died, lease_expires_at). Leases expire on a clock, so a job that outran its lease ran twice. Produce (a) every job_run_id whose attempts overlapped in wall-clock time and (b) the peak number of simultaneously running attempts per job_type with the minute it occurred. Target O(n log n). State how you treat a NULL finished_at and what clock skew does to your answer.
Approach
- Define the interval before sorting anything: an attempt occupies [started_at, COALESCE(finished_at, lease_expires_at)). finished_at is observed and lease_expires_at is only a promise, so every attempt without a finish contributes an estimate and the whole result is a lower bound on overlap rather than an exact count.
- For peak concurrency, sweep: emit 2n endpoints, sort by (timestamp, kind) with ends ordered before starts at equal timestamps, then walk the sequence maintaining a counter per job_type and record each type's maximum with its timestamp. O(n log n) dominated by the sort, O(n) space, or O(1) extra if the sort is external and the walk streams.
- For overlap detection, do not compare attempts pairwise. A single global sort by (job_run_id, started_at) gives both the grouping and the order; within a group, keep the maximum end seen so far and report an overlap exactly when the next start is less than that running maximum, which is one linear pass after the sort.
- Half-open intervals matter and are easy to get wrong: with closed intervals an attempt ending at the same millisecond another begins reads as concurrency two, and across 50,000,000 records that artefact swamps the real signal.
Follow-up
- A handler is not idempotent and you have found 400 overlapping jobs. Which of them actually caused damage, and what would you query to find out?
- Peak concurrency for one job_type is 4 against a configured cap of 4. Is the cap working, or is the data hiding attempts that never started?
How would you optimize a slow-running SQL query?
How would you optimize a slow-running SQL query?
Approach
- Name the grain you start from and join outward from it.
- Check whether any join is one-to-many before aggregating, or the sums inflate.
- Say which index the query would use, and what makes it unusable.
- 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?
Explain why the owner filter ignores the listing index
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
- 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.
- 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.
- 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.
- 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?
What are the key differences between Java 7 and Java 8?
What are the key differences between Java 7 and Java 8?
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 polymorphism and provide an example?
Can you explain polymorphism and provide an example?
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 how Spring Boot simplifies the development of Java applications.
Describe how Spring Boot simplifies the development of Java applications.
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 are the advantages of using microservices architecture?
What are the advantages of using microservices architecture?
Approach
- Fix the scope first: who calls this, how often, and what they do when it fails.
- Name the read and write paths separately; they rarely have the same bottleneck.
- Choose a partition key and say what query it makes expensive.
- 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?
Provide a solution for a given problem using data structures. What considerations did you take into account?
Provide a solution for a given problem using data structures. What considerations did you take into account?
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 design a system that handles thousands of concurrent users?
How would you design a system that handles thousands of concurrent users?
Approach
- Fix the scope first: who calls this, how often, and what they do when it fails.
- Name the read and write paths separately; they rarely have the same bottleneck.
- Choose a partition key and say what query it makes expensive.
- 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?
Edge instances grow 400 MB per hour until the nightly restart
Edge API instances start at 700 MB resident and grow about 400 MB/hour; a nightly rolling restart has hidden it for weeks. Growth continues unchanged when request rate halves overnight, p99 degrades in the last hours before an instance is recycled, and heap used immediately after a forced full GC rises monotonically. The service holds no product state. Name the discriminating measurement that separates the plausible causes, give the most likely cause, and give the fix and how you would verify it.
Approach
- Separate resident memory from live heap first, because they fail differently. Resident size can grow from fragmentation, native buffers or thread stacks while the heap is flat; heap used after a full GC rising monotonically is the measurement that says objects are reachable and not being released. You already have it, so this is retention, not fragmentation, and that closes off half the candidate list.
- Use the rate's independence from traffic as the discriminator. Growth that continues at half the request rate rules out per-request objects that are merely slow to collect and points at a structure that grows with distinct values observed rather than with call volume. Write the candidates that have that property: a metrics registry keyed on a high-cardinality label, an unevicted cache, an interner, a per-key lock map.
- Take two heap snapshots an hour apart and diff by retained size, reading the dominator tree, not by allocation count or instance count. Expect one root holding a map with millions of entries, then follow the reference chain to the code that inserts and never removes. Allocation profilers point at churn, which is the wrong signal here.
- The candidate that fits this service is an observability label carrying an identifier, such as a request path recorded before templating so that /v1/resources/48213 becomes its own metric series. That grows with distinct ids seen, is independent of rate, and explains the late p99 degradation, since GC cost rises with the size of the live set.
Follow-up
- Post-GC heap is now flat but resident size still creeps. What are you looking at, and does it matter?
- How would you have detected this before an OOM, given the nightly restart masked the trend?
Built from the rounds and topics Ness Digital Engineering candidates report.
Prepare, practise & reflect
One practical outcome each day. Spend longer where you need it.
0 / 7 done01Map the Ness Digital Engineering loop
- Write out the reported sequence: Initial Screening, Technical Interviews, Managerial Discussions, Final HR 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 4 reported rounds, with the weakest marked.
02Work Java
- Spend the session on Java, which Ness Digital Engineering candidates report being tested on.
- Write one worked example in Java and time yourself on it.
Deliverable: One timed worked example in Java.
03Work OOP (Object-Oriented Programming)
- Spend the session on OOP (Object-Oriented Programming), which Ness Digital Engineering candidates report being tested on.
- Write one worked example in OOP (Object-Oriented Programming) and time yourself on it.
Deliverable: One timed worked example in OOP (Object-Oriented Programming).
04Work SOLID Principles
- Spend the session on SOLID Principles, which Ness Digital Engineering candidates report being tested on.
- Write one worked example in SOLID Principles and time yourself on it.
Deliverable: One timed worked example in SOLID Principles.
05Answer out loud: Technical / Domain Questions
- Answer aloud, timed: What are the key differences between Java 7 and Java 8?
- Answer aloud, timed: Can you explain polymorphism and provide an example?
Deliverable: Spoken answers to 2 reported Technical / Domain Questions question(s), under time.
06Answer out loud: Problem-Solving / Case Studies
- Answer aloud, timed: How would you optimize a slow-running SQL query?
- Answer aloud, timed: Describe a time when you faced a technical challenge. How did you resolve it?
Deliverable: Spoken answers to 2 reported Problem-Solving / Case Studies question(s), under time.
07Answer out loud: Behavioral / Leadership
- Answer aloud, timed: Describe a situation where you had to work with a difficult team member. How did you handle it?
- Answer aloud, timed: What motivates you to work in a collaborative environment?
Deliverable: Spoken answers to 2 reported Behavioral / Leadership 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.
How do you handle exceptions in your code?
How do you handle exceptions in your code?
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?
Describe a time when you faced a technical challenge. How did you resolve it?
Describe a time when you faced a technical challenge. How did you resolve it?
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?
Describe a situation where you had to work with a difficult team member. How did you handle it?
Describe a situation where you had to work with a difficult team member. How did you handle it?
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 work in a collaborative environment?
What motivates you to work in a collaborative environment?
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 faced with multiple deadlines?
How do you prioritize tasks when faced with multiple deadlines?
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
How do you handle exceptions in your code?
- 02
Describe a time when you faced a technical challenge. How did you resolve it?
- 03
Describe a situation where you had to work with a difficult team member. How did you handle it?
- 04
What motivates you to work in a collaborative environment?
What is the interview difficulty level?
The interview process at Ness Digital Engineering is rigorous and requires thorough preparation. Candidates should expect a mix of technical, behavioral, and problem-solving questions that assess both hard and soft skills.
Ness Digital Engineering Software Engineer candidate reports ↗What differentiates successful candidates?
Successful candidates demonstrate a strong technical foundation and the ability to communicate effectively. They also show adaptability and a willingness to collaborate with others.
Ness Digital Engineering Software Engineer candidate reports ↗What is the company culture like?
Ness Digital Engineering promotes a collaborative and innovative environment. Team members are encouraged to share ideas and work together to create impactful solutions.
Ness Digital Engineering Software Engineer candidate reports ↗How long does the interview process typically take?
The entire interview process can take anywhere from a few days to a couple of weeks, depending on scheduling and the number of candidates being interviewed.
Ness Digital Engineering Software Engineer candidate reports ↗Is remote work an option?
While policies may vary by team, Ness Digital Engineering does offer flexible work arrangements, including remote and hybrid options.
Ness Digital Engineering Software Engineer candidate reports ↗What topics does Ness Digital Engineering test in interviews?
Ness Digital Engineering interviews most often cover Java, SQL, Angular, Problem Solving, and Stakeholder Communication. The exact emphasis depends on the specific role you apply for.
Ness Digital Engineering 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.
- 01Ness Digital Engineering 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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