Senior Engineer, Fullstack - Growth

An Introduction to PrimerPrimer is the unified infrastructure for global payments. We give finance and payments teams the visibility and control to reduce complexity, improve performance, and capture more revenue - all from a single platform.Backed by Sofina, Peak XV Partners, ICONIQ, Tencent, Accel, and Balderton, we're building the payments layer the world's best companies rely <on.Watch> our showcase >Read up on our $100m Series CLearn more about our culture >Which team will you be joining?You'll be joining the Growth team, which owns merchant onboarding and activation: everything between a new account and a first live payment. It's a newly formed team taking on a new product area for Primer, so there's a lot of scope to shape both what we build and how.Primer is remote-first and globally distributed — always will be.What will you be doing?Lead frontend architecture and technical direction for the self-serve onboarding and platform experience, with real ownership over how it's built, not just what gets shippedYou’ll spend roughly 80% of your hands-on codebase time on frontend and 20% on backend. That split is a guide, not a rule, and it will shift in either direction depending on what we're focused on at the time.Partner closely with Design to take onboarding and platform experience from concept to production, shaping the details that decide whether a merchant's first steps with Primer feels effortless or frustratingMentor and raise the bar for the engineers who join the team, you're the person newer engineers learn frontend craft fromSet frontend conventions and quality standards for a team that's still being built — architecture reviews, code quality, testing approach, all early enough that your calls stickContribute to the Python backend where it's needed to unblock frontend work or ship a feature end to end, without needing deep backend expertise going inWhat we're looking forStrong, proven frontend expertise — production experience architecting and building complex frontend applications, not just consuming a design systemComfortable being the most senior frontend voice in the room, including pushing back on design or product where the frontend reality demands itSome backend experience and a genuine willingness to work in a Python codebase — depth isn't required, but you shouldn't be reluctant to touch itExperience mentoring other engineers, ideally including people earlier in their career than youNice to have, not required:Experience building or integrating payment productsExperience in a growth, onboarding, or activation-focused product surfaceWhat you should be aware of:The team is still forming, so you're inheriting mentoring responsibility for people who haven't been hired yet — the "who" of who you're mentoring is still unknownRemote-first, high autonomy, no hand-holding — you're expected to set your own standards, not follow someone else's playbookEarly-stage team means some ambiguity on process and tooling that a more established team would already have solved✅ A typical interview processAn initial intro call with a Talent PartnerAn interview with the Hiring ManagerChallenge Stage - Contextualised to the roleA final, values-alignment interviewWhat's the culture like at Primer?We're building a culture where people can do their best work and be proud of the impact they have. You'll be working with people who are mission-driven, smart, and reflective, and who are genuinely invested in building exceptional products and delivering success for our merchants.We work remotely, and have done since day one. We believe that building a successful, profitable company goes beyond proximity. We invest in our relationships through great remote working practices and thoughtfully designed face-to-face time, including workations, our annual company retreat, and access to co-working spaces across most major cities.The work is challenging. Scaleups are a challenge, and building category-defining products is a challenge. But there's a meaningful difference between a challenge and a struggle. At Primer, the right challenge comes with the right support: strong onboarding, a collaborative environment, and a team that is genuinely invested in your success. It's never something you face alone.Our benefits🌍 We are fully remote and globally distributed; and have been since day one💰 Competitive share options🌴 Uncapped holiday, with 25 days minimum to be taken🗣️ Co-working space access across major cities📅 Workations & Company Retreat💻 The best equipment for your role🏠 £500 towards your home office setup🔎 Generous learning budget🏥 Private Medical Insurance📈 A broad set of additional perks and benefits (depending on location)Don’t meet every single requirement?At Primer, we're dedicated to building a diverse, inclusive, and authentic workplace. If you're excited about this role but your experience doesn't align perfectly with every qualification listed, we encourage you to apply. You may be the right candidate for this or other roles.Primer is committed to the equal treatment of all current and prospective employees and adopts a zero-tolerance approach to discrimination, regardless of age, disability, sex, sexual orientation, pregnancy and maternity, race or ethnicity, religion or belief, gender identity, marriage and civil partnership, or any other background or belief.