What we test for
Typical work
- A feature delivered whole, instead of split across two teams and a handover
- The first engineers on a product, when there is no one to hand the other half to
- Work that keeps crossing the API line: auth, uploads, search, anything paginated
- Gluing a third-party service in without leaving its shape all over your domain
The coding test
Add a feature that cannot be done on one side alone: a list that has to stay correct while two people edit it. They design the endpoint, the query and the interface, and we watch where they put the truth. Then we tell them the product manager wants it ten times bigger and ask what breaks first. Scored on where they drew the boundary, not on how much they wrote.
Five interview questions you can reuse
We use questions like these in our soft-skills and technical rounds. Steal them for your own interviews.
Full-stack often means weaker on one side. How do you read that in an interview?
A strong answer covers: Ask about the half they are quieter on, and ask for a decision rather than a definition. Someone strong on the server who has only ever consumed a design system will say so and then describe how they kept state out of the component anyway. The answer to listen for is a trade-off they made and regretted. What should worry you is fluency in both vocabularies with no scars in either.
A page is slow. How do you find out which end is at fault?
A strong answer covers: Measure before guessing, and measure at the boundary: how long the server took, how long the network took, how long the browser took after that. The waterfall usually settles it in a minute. The common answer is neither end: it is one query per row, or a payload carrying forty fields to render three.
Where do you put business logic when you own both ends?
A strong answer covers: On the server, and only on the server, with the client free to repeat it for the sake of a fast message. The moment a rule lives only in the browser it is advice, not a rule, because the endpoint is still reachable without it. The duplication worth having is validation; the duplication that hurts is a calculation that can disagree with itself.
What does a well-drawn API boundary look like from the inside?
A strong answer covers: The screen can change without the endpoint changing, and the table can change without either. If every new screen needs a new endpoint, the API is modelling the interface. If every endpoint returns the table, the client is doing the joining. The usual tell is a field named after a component.
When would you argue against hiring full-stack for a role?
A strong answer covers: When the hard part is unmistakably on one side: a rendering engine, a query planner, a payments ledger. Breadth is worth most where features keep crossing the line and least where the depth is the job. Being able to say that is part of being senior.
One invoice a month.
The shortlist is free. Pick the contract that suits you: monthly, six months or twelve.
What every seat includes
- Contracts, payroll and compliance handled
- Vetting: coding test, soft skills, English and a level check
- Free replacements: unlimited on 12+ months, 2 on 6 months, 1 on monthly
- A direct line to our CEO
Terms in plain words
- Monthly, six months or twelve, your choice
- Your rate is locked for the whole contract on 6 and 12+ months
- Monthly ends with 30 days’ notice
- Want to hire the developer full-time? The buyout is set in the contract from day one
Questions tech leads ask us
How senior are your Full-Stack engineers?
6+ years of professional Full-Stack work, with recent production experience.
Can I see the coding test results?
Yes. Every profile card includes the score and the reviewer's notes.
Skip the sales rep. Talk to the CEO.
Tell us what you're building, your stack and when you need people. Three vetted profiles per role within 48 hours of the call, and a straight answer on whether we're the right fit.