You prepped hard for your last product-company interview, and it still felt like a different sport when you sat down with an agency. That's because it is. Agency hiring screens for things a product interview barely touches, and strong engineers who prepare for the wrong round talk themselves out of good jobs.
How a digital agency developer interview differs from product companies
The core difference is breadth. A product company hires you to go deep on one codebase for years. An agency hires you to ship a client site in six weeks, then move to an entirely different stack for the next client.
Interviewers screen for that reality. They want proof you can pick up a legacy WordPress build, a Vue front end and a Laravel API in the same quarter without losing your footing. A product interview rewards depth. An agency interview rewards range and the calm to switch context fast.
There's a commercial angle too. Your time is billable. Every hour you spend confused is an hour the agency can't charge a client for, so hiring managers look hard at how quickly you get productive in an unfamiliar codebase. If you understand that up front, most of the interview makes more sense.
The code test: smaller, faster, closer to real work
Product companies love the algorithmic puzzle. Reverse a binary tree, find the longest palindromic substring, that sort of thing. Agencies rarely bother, because the day job is rarely CS-heavy and the test usually mirrors the work.
Expect something closer to what you'd actually build. A common format is a two to three hour take-home where you build a small component from a design file, wire up an API call and write a couple of tests. We've seen agencies hand candidates a Figma frame and ask for a responsive card layout in whatever framework the team runs.
Here's what they're really marking:
- Can you match a design closely, or do you drift 8px off and call it finished?
- Is your CSS maintainable, or a pile of magic numbers and !important?
- Did you handle the loading and error states, or only the happy path?
- Can a colleague read your commit history and follow your thinking?
Speed of communication counts as well. Some agencies now run a live pairing session instead of a take-home, where a developer sits with you for 45 minutes while you work through a small bug in their actual codebase. They aren't watching for a perfect answer. They're watching whether you ask sensible questions, narrate your thinking and stay composed when you hit something unfamiliar. Talk through what you're doing, because silence reads as panic.
A word on take-homes. If an agency asks for more than about four hours of unpaid work, push back or walk away. Good agencies respect your time because they charge clients for theirs, and a growing number now pay for test tasks. That's the right direction, and it tells you something about how they treat their people.
Portfolio reviews carry more weight than at product firms
At a product company your GitHub might barely come up. At an agency, your portfolio often is the interview. You'll walk two or three people through work you've shipped, and they will dig into the detail.
Line up three projects you can talk about for ten minutes each. For every one, know the brief, the constraint that made it hard, the trade-off you settled on and what you'd do differently now. Agency interviewers care less about the framework and more about your judgement under a client deadline.
Bring the messy stories. The project where the client changed scope two days before launch. The build you inherited with no documentation and a font licence nobody had paid for. How you handled those moments tells an agency how you'll behave when their Thursday goes sideways, and it will.
One front-end lead at a Manchester agency told us she rejects candidates who only show polished case studies. She wants to hear about the compromise, the corner of the site the budget didn't stretch to. Glossy portfolios hide how someone actually works when the money runs low.
If your best work sits behind an NDA or has been redesigned since you left, say so and describe it anyway. A rebuilt local screenshot or a short Loom walkthrough beats a dead link and a shrug.
Still deciding whether agency life suits you at all? Our guide to agency developer vs product developer breaks down the day-to-day difference before you commit to the interview.
Cultural fit is really about client-facing skills
Every company claims to interview for culture. Agencies mean something specific by it. They're checking whether they can put you in front of a client without wincing.
You may not own the account, but you'll join calls, explain why a feature slipped, and translate "the carousel feels janky on mobile" into an actual bug ticket. Interviewers test this with questions that sound soft and aren't:
- "A client asks for something you think is a bad idea. What do you do?"
- "How would you explain to a non-technical client why the site needs another week?"
- "Tell us about a time a project went wrong. What did the client see?"
The answer that sinks you is engineering purity: refusing the bad idea flat, or hiding behind jargon until the client gives up. The answer they want shows you can hold a technical line and keep the relationship intact. You'd explain the cost of the request in plain terms, offer an alternative, and let the client decide with the facts in front of them.
Pace comes up too. Agency work runs in short cycles with several projects live at once. Expect questions about how you juggle competing deadlines and what you do when two account managers both need you today. If you thrive on a single long roadmap, be honest about it, because the rhythm here is constant context-switching.
Do your homework on the agency itself
Turn up knowing their work. Agencies publish case studies for a reason, so read three or four recent ones and form a real opinion. Walking in with "I liked the interaction work on the site you built for that charity, was that GSAP or something lighter?" shows you think like someone who ships, not someone reciting a framework list.
Check the stack before you arrive. If they're a Laravel and Vue shop and you've spent five years in React and Node, have a straight answer for how you'll ramp up. Our rundown of the tech stacks UK agencies actually use is a sensible place to start.
Know their client mix, because it shapes everything. An agency working mostly with ecommerce brands hires differently from one building brochure sites for law firms. The first obsesses over performance budgets and conversion. The second cares about turnaround speed and a clean CMS handover the client can manage themselves.
It pays to know who you'd be reporting to as well. In smaller agencies a developer often answers to a project manager with no technical background, which changes how you explain estimates and risk. Ask about it. The reporting line tells you more about your daily life than the job title does.
Questions worth asking them back
The questions you ask reveal how much agency experience you really have. Weak candidates lead with holiday allowance and remote policy. Strong ones ask about the work:
- How many projects will I be running at once?
- Who owns the client relationship, and where do developers sit in it?
- What happens when a project overruns, and who absorbs the cost?
- How much of the work is greenfield versus maintenance?
- What does handover look like when a project ends?
That last question matters more than people expect. Agencies live or die on clean handover. If nobody can answer it clearly, you'll spend your evenings firefighting sites that shipped without documentation, and you'll learn that the hard way.
A short prep checklist
Give yourself a week if you can. This is what actually moves the needle:
- Rehearse three project walkthroughs out loud, timed to ten minutes each.
- Rebuild a small component from a Figma file in their stack, so the code test feels like ground you've walked.
- Read four of their case studies and form one honest opinion on each.
- Prepare two stories about projects that went wrong and how you steadied them.
- Write down five questions for them, weighted towards the work rather than the perks.
None of this is about gaming the process. Agency hiring rewards the same things the day job does: shipping under pressure and choosing the right trade-off when there's no perfect answer. Prepare for that and the interview mostly takes care of itself.
When you're ready to line up interviews, browse the latest developer jobs on Digital Agency Jobs and apply to the agencies whose work you'd be proud to show off.
