Sms Group · Software Engineer
Updated · 2026-10-02

Sms Group Software Engineer
Interview Guide

THE 60-SECOND BRIEF

At SMS group, a Software Engineer does not simply write code for typical consumer web applications. You will be building market-leading software solutions that directly power, optimize, and automate the metals industry. As the world's leading partner in metallurgical plant construction and mechanical engineering, SMS group integrates complex software systems with massive physical machinery to drive the future of sustainable steel production, famously known as "green steel." Your work will bridge the gap between heavy industrial equipment and modern digital solutions. Whether you are developing 3D visualization interfaces in React JS or backend business logic in C#, your contributions will directly impact the efficiency, safety, and environmental footprint of steel mills and production plants globally.

This guide is scoped to a Software Engineer candidate at Sms Group.

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

Stress-strain diagrams & material behaviorCoding (general programming assessments)Problem-solving skills

25 min read

Browse Software Engineer questions

See the practice prompts

19Practice promptsAcross five skill areas

At SMS group, a Software Engineer does not simply write code for typical consumer web applications. You will be building market-leading software solutions that directly power, optimize, and automate the metals industry. As the world's leading partner in metallurgical plant construction and mechanical engineering, SMS group integrates complex software systems with massive physical machinery to drive the future of sustainable steel production, famously known as "green steel." Your work will bridge the gap between heavy industrial equipment and modern digital solutions. Whether you are developing 3D visualization interfaces in React JS or backend business logic in C#, your contributions will directly impact the efficiency, safety, and environmental footprint of steel mills and production plants globally. This unique combination of physical-digital integration makes the Software Engineer role at SMS group both intellectually challenging and highly impactful. ##### Tip Depending on the specific office and team you are interviewing with, the technical focus can shift dramatically between modern web development (React/C#) and heavy industrial automation engineering.

01

Recruiter Call

reported

Initial screening call with a recruiter to discuss your background, experience, and interest in the company.

What to demonstrate

  • Initial screening call with a recruiter to discuss your background, experience, and interest in the company
  • Depth in Stress-strain diagrams & material behavior

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.
Sms Group Software Engineer candidate reports ↗
02

Technical Assessments

reported

Series of technical assessments including online aptitude tests, coding quizzes, or technical panel interviews.

What to demonstrate

  • Series of technical assessments including online aptitude tests, coding quizzes, or technical panel interviews
  • Depth in Stress-strain diagrams & material behavior

How to prepare

  • Answer aloud and timed: Describe your experience with C# and how you implement asynchronous programming to handle high-throughput backend tasks.
  • Answer aloud and timed: What strategies do you use to ensure seamless communication between a web-based client and an on-premise industrial database?
Sms Group Software Engineer candidate reports ↗
03

In-depth Discussions

reported

For engineering headquarters roles, prepare for discussions around physical engineering concepts and hands-on problem-solving.

What to demonstrate

  • For engineering headquarters roles, prepare for discussions around physical engineering concepts and hands-on problem-solving
  • Depth in Stress-strain diagrams & material behavior

How to prepare

  • Answer aloud and timed: Explain the working principles and applications of an IGBT (Insulated-Gate Bipolar Transistor).
  • Answer aloud and timed: Describe the basic components of a industrial refrigeration cycle, specifically focusing on the roles of compressors and condensers.
Sms Group Software Engineer candidate reports ↗

PracHub editorial advice for the preparation topics above.

01

Know your resume inside out

Be ready to discuss any project, technology, or academic subject you have listed on your resume in great detail.

02

Prepare for cross-disciplinary interviewers

Your interview panel may include mechanical or process engineers. Practice explaining software concepts in simple, practical terms.

03

Stay calm during unexpected questions

If you are asked a mechanical or electrical question that you do not know the answer to, explain your thought process and how you would go about finding the solution rather than guessing.

04

Avoid being overly defensive or aggressive if an interviewer challenges your technical answers

Maintain a collaborative and professional attitude throughout the discussion.

Choose a category, try a prompt, then open its approach, worked solution or follow-up when you need it.

16 technical prompts0 include a worked solution

Archive a resource graph without breaking live references or recursing

medium
graph traversaltopological ordertenant isolation

Resources reference other resources within a tenant; for the largest tenant the reference table holds up to 2,000,000 nodes and 8,000,000 edges. Archiving a resource must archive everything reachable from it that nothing outside the set still references, refuse when a live external referrer exists, and terminate when references form cycles, which they legitimately do. Produce the archive order and the refusal list, targeting O(V+E). Say what stops the traversal crossing a tenant boundary, and why recursion is the wrong control structure at this size.

Approach
  1. Load the subgraph with the tenant predicate on both endpoints of the edge, not only on the side you started from. Scoping the left table alone is the classic cross-tenant leak: one mis-entered edge then pulls another tenant's resources into the traversal and, worse, into the archive.
  2. Traverse iteratively with an explicit stack. A 2,000,000-node graph can hold a chain deep enough to exhaust a native stack in the low tens of thousands of frames, and that failure is a process crash rather than an error you can return.
  3. Treat cycles as data rather than corruption: compute strongly connected components with Tarjan in O(V+E) using its own explicit stack, then condense. The condensation is a DAG, so a topological order over it gives the archive order, and every member of a component archives in one transaction because no order within a cycle is valid.
  4. Decide refusals with reverse edges. A candidate is archivable only if every in-edge originates inside the candidate set, so build the transpose or count in-degrees restricted to the visited set, and emit each blocked resource with the id of the external referrer, which is the only part of the answer an operator can act on.
Follow-up
  • The graph is read in one query and the archive writes a minute later. What can change in between, and how do you make the write safe?
  • The candidate set is 400,000 resources. Is that one transaction, and if not, what does a half-finished archive look like to a reader?

Diff a projection against the primary without per-row point reads

hard
reconciliationrange hashingthrottling

The listing projection has drifted and some rows show a stale version. The primary holds 40,000,000 resource rows across 12,000 tenants while serving 1,200 writes and 14,000 reads per second. The obvious repair, reading each resource row and comparing its version against the projection, is correct and would eventually finish. Explain precisely why it is unacceptable here, then give a diff that finds the differing rows, state its complexity, and make it safe to run against a live primary. Replication lag is usually under 100 ms and is not bounded.

Approach
  1. Quantify the naive cost rather than calling it slow: 40,000,000 point reads at even 0.5 ms each is over five hours serialised, and the only lever is concurrency, which is exactly what you cannot spend. The primary's pool is sized for the write path, and 40,000,000 random reads evict the buffer cache that sustains the 85 percent cache hit rate, so the audit degrades the system it is auditing.
  2. Replace random access with one ordered pass per side. Both sides can be read in (tenant_id, resource_id) order, which is a sequential scan on each and a merge join in O(n) time and O(1) memory. For a dense diff that is the whole answer, and it reads the primary once instead of 40,000,000 times.
  3. For the expected sparse case, compare range hashes instead of rows: partition the key space, compute per range an order-independent aggregate over hash(resource_id, version), compare aggregates, and descend only into ranges that differ. With d differing rows and branching factor B, at most d ranges mismatch per level, so the drill-down examines O(d log_B(n/d)) ranges and reads full rows only in mismatching leaves.
  4. Aggregate with a sum modulo 2^64 or a multiset hash, never XOR. XOR is order-independent but self-cancelling, so two rows wrong in the same way, or a row duplicated on one side, leave the range aggregate matching and the range is declared clean.
Follow-up
  • The diff reports 900 stale rows. How do you decide between patching those rows and rebuilding the projection from resource_revision?
  • Same job, but the projection lives in a search index that cannot be scanned in key order. What changes?

Collapse a redelivered event batch into per-aggregate high-water marks

easy
hashingat-least-onceaggregation

You drain a batch of up to 5,000,000 events, each (aggregate_id BIGINT, aggregate_version INT, event_type, payload). The log guarantees order within one aggregate only; the batch merges 64 partitions, and a relay failover has redelivered a range, so an older version for an aggregate can appear after a newer one. Given a map of last_applied_version per aggregate, produce the events worth applying, at most one per (aggregate_id, version), plus the count discarded. Target O(n) time. State the memory for 2,000,000 distinct aggregates and what you do when it does not fit.

Approach
  1. One pass, one hash map from aggregate_id to the highest version kept, and a discard counter. An event whose version is at or below last_applied_version for its aggregate is dropped without further work, which is the whole reason the event carries its version rather than a delta. O(n) expected time, O(d) space in distinct aggregates.
  2. Keep the maximum, never the last occurrence. The redelivered range means the final appearance of an aggregate in the batch can be an older version than one seen earlier in the same batch, so last-wins applies stale state over newer state and the projection regresses with no error anywhere.
  3. Cost the memory instead of calling it large: an 8-byte key plus a 4-byte version is 12 bytes of payload, and an open-addressed table held at a 0.7 load factor costs roughly 17 bytes per entry before per-slot metadata, so 2,000,000 aggregates is tens of megabytes in a native layout and several times that in a runtime that boxes both key and value.
  4. If the distinct set exceeds memory, partition on hash(aggregate_id) mod P and reduce each partition independently. Every event for one aggregate hashes to the same partition, so the per-partition result is exact and the merge is concatenation rather than a second reduction.
Follow-up
  • The payload is a patch rather than a snapshot, so applying only the highest version loses the intermediate changes. What changes in your reduction?
  • How do you detect that version 7 arrived while version 6 was never delivered, and what should the consumer do about the gap?

Built from the rounds and topics Sms Group candidates report.

Small steps. Visible outcomes.0 / 7 completed
ONE WEEK · YOUR PACE

Prepare, practise & reflect

One practical outcome each day. Spend longer where you need it.

0 / 7 done
01Map the Sms Group loop
  • Write out the reported sequence: Recruiter Call, Technical Assessments, In-depth Discussions.
  • For each round, write one sentence on what it is judging, from the description above, and mark the one you are least ready for.

Deliverable: A one-page map of the 3 reported rounds, with the weakest marked.

02Work Stress-strain diagrams & material behavior
  • Spend the session on Stress-strain diagrams & material behavior, which Sms Group candidates report being tested on.
  • Write one worked example in Stress-strain diagrams & material behavior and time yourself on it.

Deliverable: One timed worked example in Stress-strain diagrams & material behavior.

03Work Coding (general programming assessments)
  • Spend the session on Coding (general programming assessments), which Sms Group candidates report being tested on.
  • Write one worked example in Coding (general programming assessments) and time yourself on it.

Deliverable: One timed worked example in Coding (general programming assessments).

04Work Problem-solving skills
  • Spend the session on Problem-solving skills, which Sms Group candidates report being tested on.
  • Write one worked example in Problem-solving skills and time yourself on it.

Deliverable: One timed worked example in Problem-solving skills.

05Answer out loud: Software Engineering & Web Development
  • Answer aloud, timed: How do you design a scalable relational database schema for tracking real-time sensor data from a rolling mill?
  • Answer aloud, timed: Explain how you would optimize a React JS frontend that needs to render complex, real-time 3D visualizations.

Deliverable: Spoken answers to 2 reported Software Engineering & Web Development question(s), under time.

06Answer out loud: Engineering Foundations & Systems
  • Answer aloud, timed: Explain the working principles and applications of an IGBT (Insulated-Gate Bipolar Transistor).
  • Answer aloud, timed: Describe the basic components of a industrial refrigeration cycle, specifically focusing on the roles of compressors and condensers.

Deliverable: Spoken answers to 2 reported Engineering Foundations & Systems question(s), under time.

07Answer out loud: Academic & Project Discussion
  • Answer aloud, timed: Walk us through your university thesis or final-year engineering project. What was the biggest technical challenge you faced, and how did you resolve it?
  • Answer aloud, timed: What was your favorite subject in university, and how does it apply to the work we do at SMS group?

Deliverable: Spoken answers to 2 reported Academic & Project Discussion 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.

Describe your experience with C# and how you implement asynchronous programming to handle high-throughput back

medium
Software Engineering & Web Development

Describe your experience with C# and how you implement asynchronous programming to handle high-throughput backend tasks.

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?

Argue against a design, lose, and commit anyway

medium
disagreementservice boundariesdecision records

Describe a design you argued against and lost. State the failure you predicted as a named mechanism, not a feeling about complexity: two services that would need one transaction, a projection with no rebuild path, a write path with no idempotency key. Say what evidence you brought, what the decision maker weighed instead, and what you did after the decision was made: what you instrumented, what you wrote down, and whether the prediction came true. Five minutes.

Approach
  1. State the prediction in falsifiable form up front: the mechanism, the condition that triggers it, and the observable outcome. A prediction that cannot be checked also cannot be credited to you later.
  2. Show the evidence you had at the time and label each piece honestly as measured, analogous, or intuition. Keeping the intuition is fine; disguising it as data is the thing that erodes your standing in the next argument.
  3. Represent the opposing case at full strength, including the constraint you did not control: a fixed date, a team boundary, or the fact that the decision was cheap to reverse and yours was not.
  4. Make disagree-and-commit concrete. Name the artefact you left behind so the prediction could be settled without you: the alert and its threshold, the counter on the dashboard, the decision note that recorded the trade-off and the condition that would revisit it.
Follow-up
  • What threshold on that alert would have proved you right, and did anyone ever look at it?
  • If the same proposal arrived tomorrow with the same deadline, would you argue it the same way?

Unblock an engineer without taking the keyboard

easy
mentoringleasesat-least-once

A teammate has spent two days on a job handler that occasionally writes duplicate rows. They are certain the queue is delivering twice by mistake. You suspect a lease expiring under a slow handler, so the job is running concurrently with itself. Describe how you have unblocked someone in this position: what you asked before offering a hypothesis, what you showed them rather than told them, and what you left them owning. Then say what you would do if their theory turned out to be the right one.

Approach
  1. Ask before diagnosing, and ask for things answerable from data they already have: the attempt count on the job rows that produced duplicates, the handler's observed duration against its lease expiry, and whether the duplicate rows share a natural key that a unique constraint could have caught.
  2. Teach the shape rather than the answer. A lease cannot distinguish a dead worker from a slow one, so a handler that outruns its lease is running twice by design, and deploys deliver the other half by killing handlers mid-run on every rollout. Both of their candidate theories produce identical duplicate rows, which is why the evidence has to come from timings rather than from argument.
  3. Hand over a checklist they execute: a natural key on every write the handler performs so the second copy collides rather than appends, the record of intent written before any external effect, a lease heartbeat while running, and the metric that shows it working.
  4. Keep ownership with them deliberately. Pair on the first write, then step back; if you finish it yourself you have closed one ticket and left the same person stuck on the next redelivery.
Follow-up
  • How would you distinguish a genuine double-delivery from a lease expiry using only the data already stored?
  • Their handler calls an external endpoint before recording that it did. What do you tell them to change first?
  • 01

    Describe your experience with C# and how you implement asynchronous programming to handle high-throughput backend tasks.

  • 02

    Describe a design you argued against and lost. State the failure you predicted as a named mechanism, not a feeling about complexity: two services that would need one transaction, a projection with no rebuild path, a write path with no idempotency key. Say what evidence you brought, what the decision maker weighed instead, and what you did after the decision was made: what you instrumented, what you wrote down, and whether the prediction came true. Five minutes.

  • 03

    A teammate has spent two days on a job handler that occasionally writes duplicate rows. They are certain the queue is delivering twice by mistake. You suspect a lease expiring under a slow handler, so the job is running concurrently with itself. Describe how you have unblocked someone in this position: what you asked before offering a hypothesis, what you showed them rather than told them, and what you left them owning. Then say what you would do if their theory turned out to be the right one.

PracHub preparation framework ↗
How technical are the interviews at SMS group?

The interviews are highly technical but broad. Depending on the team, you may face a mix of coding assessments, system design discussions, and fundamental engineering calculations. Preparing for both software and basic physical engineering concepts is highly recommended.

Sms Group Software Engineer candidate reports ↗
Why does a Software Engineer role require mechanical or electrical engineering knowledge?

Because our software directly controls and optimizes massive physical machinery, our engineers must understand the physical processes they are automating. This cross-disciplinary knowledge ensures our software is safe, efficient, and reliable.

Sms Group Software Engineer candidate reports ↗
What is the typical timeline for the hiring process?

The process typically takes between three to six weeks from the initial screen to the final offer, depending on the location and the availability of the interview panels.

Sms Group Software Engineer candidate reports ↗
Is there an onsite interview or office visit involved?

Yes, in many locations, successful candidates are invited to an onsite interview. This often includes a technical panel, a whiteboard session, and sometimes a shop or factory tour to give you a firsthand look at our machinery.

Sms Group Software Engineer candidate reports ↗
What topics does Sms Group test in interviews?

Sms Group interviews most often cover Digital Electronics, Microprocessors, Microcontrollers, Test Case Design, and Risk Management. The exact emphasis depends on the specific role you apply for.

Sms Group 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.