Why pre-screen robotics software engineers before the technical loop
The gap between simulation and hardware is where robotics engineers are made. A controller that behaves perfectly in a simulator meets sensor noise, timing jitter, a loose connector and a floor that is not level, and none of that appears in a resume. Engineers who have spent time with a robot that will not do what it did yesterday build differently, and they instrument for it. A short screen asks what hardware taught them that simulation did not.
What actually matters when screening Robotics Software Engineer candidates
- 01
Technical proficiency
Probe depth in C++ and Python on ROS or ROS 2: nodes, tf2 frames, real-time control loops, SLAM stacks, MoveIt or custom motion planners, and driver integration over CAN or EtherCAT.
- 02
Systems and trade-offs
Ask how they traded perception latency against accuracy, chose sensor fusion (EKF versus factor graph), or partitioned compute between onboard microcontrollers, Jetson boards, and fleet software.
- 03
Evidence and rigour
Check how they validate: rosbag replay, Gazebo or Isaac Sim regression suites, hardware-in-the-loop rigs, unit tests on kinematics, and metrics like localisation drift or pick success rate.
- 04
Collaboration and communication
Look for work alongside mechanical, electrical, and controls engineers plus field technicians: interface contracts, bring-up of new hardware revisions, and triaging failures reported from deployed robots.
Pre-screening questions to ask Robotics Software Engineer candidates
12 questions grouped by what they test. Ask the same set in every screen and score answers on a consistent scale, or send them as an async video screen and compare answers side by side.
Robots that ran
3 questions01Have you worked with specific types of robots such as industrial, mobile or service robots?
Listen forNamed platforms they brought up on hardware, with what they owned and how long the system actually ran.
Robot types listed with no hardware time, or work limited to a simulated environment.
02Can you provide an example of a project that involved both hardware and software integration?
Listen forBring-up described concretely including a problem at the boundary, such as timing, wiring or a driver behaving unexpectedly.
Integration described as someone else's task, or no involvement once the code left their machine.
03Can you discuss a time when you had to optimise the performance of a robotic system?
Listen forA measured bottleneck with the profiling that found it, and what the fix cost in accuracy or elsewhere in the loop.
Optimisation applied without measurement, or performance improved with no number attached.
Real-time and safety
3 questions04How do you handle real-time constraints when developing robotics software?
Listen forTiming treated as a requirement with jitter measured, and a case where a missed deadline caused visible misbehaviour.
Real-time described as fast code, or no measurement of loop timing under load.
05What approaches do you use for ensuring the reliability and safety of your software?
Listen forA defined safe state with how it is reached when a component stops responding, plus watchdogs and limits in place.
Safety treated as a hardware interlock only, or no defined behaviour when a sensor drops out.
06What methodologies do you use for software testing in robotics?
Listen forTests at several levels including hardware in the loop, with a regression a test caught before it reached a robot.
Testing limited to running the robot and watching, or no automated tests at all.
Sensors and state
3 questions07Explain your experience with sensor integration and data fusion in robotics.
Listen forSensor characteristics understood, including noise, latency and failure modes, with fusion tuned against real measurements.
Sensors treated as accurate sources of truth, or fusion parameters left at default values.
08How do you approach the problem of localisation and mapping in autonomous robots?
Listen forA working system with the failure cases named, such as featureless corridors or drift, and how they were handled.
Localisation described from the literature only, or no awareness of where the approach breaks down.
09What is your experience with path planning algorithms for robots?
Listen forPlanner chosen for the environment with real constraints included, such as dynamics, clearance and replanning rate.
Planners named with no deployment, or planning treated as solved without accounting for a moving world.
Debugging on hardware
3 questions10How do you go about debugging complex software issues in a robotic system?
Listen forA bug that only appeared on hardware, with the logging or instrumentation they added and the confirmed cause.
Problems all reproducible in simulation, or debugging that stops when the symptom disappears.
11Describe a situation where you had to troubleshoot a communication issue between robotic components.
Listen forDiagnosis that separates timing, bandwidth and physical layer causes, with the evidence that pointed to each.
Communication problems solved by restarting nodes, or a fault attributed with no evidence.
12What has been your experience with robotic simulation tools?
Listen forSimulation used deliberately with a clear view of what it does not model, and where results diverged from hardware.
Simulation results treated as validation, or no known divergence between simulated and real behaviour.
How to score responses
Score every candidate on the same four criteria immediately after the screen. At this stage you are shortlisting for panel interviews, not making the final call.
Technical proficiency
35%5Names specific stacks (Nav2, MoveIt, Cartographer), explains tf tree design and controller timing, and discusses determinism on real hardware.
Systems and trade-offs
25%5Weighs compute budget, sensor cost, and safety margins explicitly, with a reasoned choice they later validated or reversed on data.
Evidence and rigour
25%5Cites measured before and after numbers, replayed logs to reproduce field failures, and trusts simulation only where correlated with hardware.
Collaboration and communication
15%5Describes joint bring-up sessions, writes interface docs others use, and translates field failure reports into precise, reproducible engineering tickets.
A controller that is perfect in the simulator meets noise, jitter and a floor that is not level. A one-way video screen asks what hardware taught them.
Try it on HirevireScreening FAQ
Process basics
How long should a pre-screening round for a robotics engineer take?
Fifteen minutes across eight to ten questions, answered async. Enough to establish what ran on real hardware, hear one hardware-only bug, and check how they think about real-time constraints and safety.
How much should simulation experience count?
It is necessary and not sufficient. Simulation is how most development happens, but an engineer who has never brought a system up on hardware will underestimate sensor noise, timing and the failures that only occur physically.
Evaluating answers
What is the strongest signal when screening a robotics engineer?
A bug that only appeared on hardware. Engineers with real robot time describe the symptom, the instrumentation they added and the cause. Anyone whose problems were all reproducible in simulation has not been in the lab.
How do I judge safety answers?
Ask what happens when a component stops responding. Sound answers describe a defined safe state and how it is reached. Anyone who has not thought about failure behaviour is dangerous around a machine that can move.
Go deeper on this role
Sanat has been hiring since 2012 and watching the recruitment industry change up close ever since, and turned that screening process into Hirevire's video screening platform. LinkedIn
