Key takeaways
- Vetting a software developer starts with defining the work and the level you need, not with the CV.
- A good technical interview combines a practical task, a code review and a system design discussion scaled to the candidate's seniority.
- Communication and English matter as much as code for remote engineers, so test them in the interview itself.
- Compare candidates against the level the work actually needs and your budget, rather than hiring the most senior person available.
- DevKit's senior engineers interview every candidate and share interviewer notes, level, English, time zone and monthly rate, so you can skip early screening rounds.
How do you vet a software developer?
To vet a software developer, define the work and the level first, screen the CV for evidence rather than keywords, then run a technical interview with a practical task, a code review and a system design discussion scaled to seniority. Finish with a check on communication, references and a short trial period with clear goals.
Each step answers a different question. The definition tells you what good looks like. The interview tells you whether the candidate can do it. References and the trial period tell you whether they will do it consistently inside your team.
Start by defining the work and the level you need
Most hiring mistakes happen before the first interview. Write down what the engineer will do in their first three months: the codebase, the stack, the problems to solve and how much guidance they will get. That tells you whether you need a junior, a mid-level, a senior or a tech lead.
Be honest about the level. A senior engineer on routine feature work is often bored and expensive, while a junior engineer without mentoring will struggle. Match the level to the work, then to the budget.
- Main stack and must-have skills versus nice-to-haves
- Ownership expected: tasks, features, systems or the whole team
- Who reviews their code and who they report to
- Required time zone overlap and English level
CV red flags to watch for when screening developers
A CV is a starting point, not proof. Look for concrete evidence of what the person built and their role in it. Long lists of technologies with no context tell you little.
None of these flags should disqualify someone on their own, but each one deserves a direct question in the interview.
- Skill lists that cover every framework but projects that describe none of them
- Vague descriptions such as "worked on" or "participated in" with no outcome or ownership
- Seniority titles that don't match the scope of the work described
- Frequent very short engagements with no explanation
- No mention of testing, code review or production support for a senior role
Technical interview checklist: structure by seniority
A strong technical interview has three parts. A practical task shows how the candidate actually writes code: keep it short and close to your real work, and ask them to talk through decisions. A code review exercise, where they review a small pull request with planted issues, shows judgment, attention to detail and how they give feedback.
The third part is system design, and it should scale with seniority. Juniors can skip it or discuss a single component. Mid-level engineers should design a feature end to end. Seniors and tech leads should handle trade-offs, scaling, failure modes and how they would guide a team through the build. Many teams now also ask how candidates use AI coding assistants and how they review generated code.
Communication is part of the interview, not a separate step. For remote engineers, check that they can explain a technical decision clearly in English, ask good questions when requirements are unclear and write a short, readable summary.
| Level | Practical task | Code review | System design | Communication and ownership |
|---|---|---|---|---|
| Junior | Clean, working code on a small, well-defined task; basic testing | Spots obvious bugs and naming issues | Not required, or one simple component | Asks for help early, follows feedback |
| Mid-level | Builds a complete feature with tests and sensible structure | Finds logic, edge-case and readability issues | Designs a feature end to end within an existing system | Works independently on tasks, explains choices clearly |
| Senior | Solves an ambiguous problem, makes trade-offs explicit | Raises design, performance and security concerns with clear reasoning | Designs a service or system, covers scaling and failure modes | Owns features to production, mentors others |
| Tech lead | Reviews or shapes an approach more than writing it from scratch | Gives feedback that improves the team's standards | Sets architecture, plans migrations, balances delivery and technical debt | Aligns engineers and stakeholders, makes and explains decisions |
References and trial period expectations
References are most useful when you ask specific questions: what did this person own, how did they handle a production issue, would you work with them again? Generic praise tells you little, so listen for concrete examples.
A trial period is the final check. Set two or three clear goals for the first weeks, such as shipping a small feature, completing a code review cycle and joining on-call or standups, and review progress together. Don't expect full speed immediately; look for steady ramp-up, good questions and code that passes review.
How to compare developer candidates against your budget
Score every candidate against the same criteria from your role definition, using the interview notes rather than memory. Then compare the result with the cost. The best choice is the candidate who meets the level the work needs at a rate you can sustain, not automatically the most experienced one.
If two candidates are close, prefer the one with stronger communication and time zone overlap for a remote role. If nobody meets the bar, widen the search instead of lowering the standard.
How engineer-led vetting saves you time
Running this full process for every candidate takes real engineering time, which is often the scarcest resource on the team. If you have a strong in-house hiring process and time to run it, keep it. If you don't, a staffing partner can do the heavy lifting.
At DevKit, every candidate passes a technical interview with our senior engineers. Each profile includes interviewer notes, level, English, time zone, availability and a clear monthly rate, so you start with evidence instead of a raw CV. We match you with engineers from our own team and private network, including senior people who are rarely on job boards, share shortlisted CVs in 3–5 business days and offer free replacement with handover if an engineer isn't a fit.
Talk to us about your hiring needs
Tell us the roles you need. We reply within one business day and send vetted CVs in 3–5 days.
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