Technology & IT

How technology employers screen candidates

Technology hiring splits into two questions that employers ask separately, and confusing them is the most common reason good candidates do badly. The first is whether you can think in a structured way about a problem you have not seen before. The second is whether you can write and reason about code well enough to work in a team. Aptitude and reasoning tests measure the first; coding exercises, take-home tasks and technical interviews measure the second. A strong result on one does not substitute for the other.

The reasoning half is often the more neglected, because it feels less like the job. A 20-minute logical reasoning section rewards a different discipline from the one that writing production code builds, and it is easy to meet it without having practised it under time. If your invitation names a reasoning or aptitude stage, treat it as a skill in its own right rather than something your day job already covers.

Assessment types in technology hiring

Most technology processes use two or three of the following, and the mix tells you what the employer is worried about. A heavy coding stage usually means the team has been burned by candidates who interview well. A heavy reasoning stage usually means the role involves debugging unfamiliar systems.

• Logical and deductive reasoning. Short argument or constraint problems where the answer must follow from the statements given. Often the first filter.
• Inductive and pattern reasoning. Sequences, grids and rule-finding tasks. Measures how quickly you form and test a hypothesis rather than how much you already know.
• Numerical reasoning. Tables, rates and proportional reasoning. More common in data, infrastructure and finance-adjacent technology roles than candidates expect.
• Coding exercise or take-home task. Usually assessed on correctness first and clarity second. A working inelegant solution beats an elegant broken one.
• Technical interview. Live problem-solving, system discussion, and questions about past decisions. Thinking aloud is usually scored, silence is not.

A method for reasoning sections under time

Reasoning sections are lost more often to untested assumptions than to slow arithmetic. The routine below is short on purpose and is meant to be used during the test, not studied as theory.

1. Write the constraint down in symbols or a single sentence before you start manipulating anything.
2. For a sequence, test the simplest rules first: constant difference, then constant ratio, then alternating operations, then a rule that combines two previous terms.
3. For a constraint problem, try to construct a counterexample to your first answer. If you can build one, the answer is wrong.
4. For data questions, identify the exact quantity asked for before reading the table. Reading the whole table first costs more time than it saves.
5. Check the units and the direction of any comparison. Percentage-of and percentage-change are different questions and both appear.
6. If an item resists a simple method, mark it and move on; return only if time allows.

Worked examples

Common mistakes in technology assessments

• Treating the reasoning stage as a formality. It is often the stage that removes the largest share of candidates, and it is a distinct skill.
• Assuming the longest rule is the intended one. If a simple rule fits every term, the simple rule is correct; the test is not trying to trick you into complexity.
• Silence during a live technical interview. Interviewers usually want the reasoning, including dead ends described briefly. Restarting silently reads as being stuck.
• Optimising before it works. In take-home tasks, correctness and a clear structure score first; premature abstraction often costs more than it saves.
• Ignoring the stated format. A take-home task with a fixed-length brief usually expects a bounded solution, not a rewrite of the surrounding project.

Where to go next

Practise the format named in your invitation under the same time limit, then review every explanation. For the coding side, the most reliable improvement is writing a short solution to one problem a day and explaining each step out loud, because that is what a technical interview scores.

• Logical and deductive reasoning practice
• Inductive reasoning practice
• Numerical reasoning practice
• Spatial reasoning practice
• All cognitive test intros
• Employer hiring guides

Frequently asked questions