Senior Data Scientist

Marshmallow
London
4 days ago
Applications closed

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We started Marshmallow when we found out how unfair insurance prices are for people who move to the UK. All because the industry hasn’t given this huge cohort of people a second’s thought, and isn’t set up to price them properly.

We saw an opportunity to do things differently, so we made it our mission to back the ones who step outside the norm. Since we started, we’ve helped 100,000s of people get a fairer deal on their car insurance. Using technology, we serve people that are often overlooked by financial services companies, solving important problems for people who need it most.

We know there are millions of marginalised customers out there. And we know that they face unique problems that most companies aren’t even aware of. We believe that our future is helping these people by learning about their experiences, and building our company around their needs. And there are strong signs that there’s a need for a company like us. Earlier this year we hit profitability, which is a huge milestone, but the most exciting thing is that we’re only just getting started.

How We Work

We’re really proud of the culture we’ve created. We push for progress every day, because we know that we’ll only hit big milestones by taking lots of smaller steps. We’re always open to helping our team mates, sharing our ideas, experience and knowledge to solve problems together. We take risks, think creatively and experiment relentlessly to meet our customer’s needs, and never pass blame when things go wrong. We encourage people at all levels to take ownership of their work, and to be bold in challenging how we do things. Everyone has a voice and the opportunity to make an impact.

And autonomy and ownership are only possible with clear direction. That’s why we collaborate to do in-depth planning twice a year, and make sure we leave with clear goals and objectives that flow from top to bottom. To make sure we’re as aligned as possible across functions, most of our work rolls up into four tribes; Acquisition, Retention, Claims and Pricing, Underwriting & Fraud. Each tribe has multiple teams embedded in it, working cross-functionally to do great work.

We’re so excited for all of the challenges up ahead, and we need more people to help us tackle them! If life at Marshmallow sounds like it could be for you, explore our culture handbook or read our blog to find out more.

The Acquisition Data Science Team

We’re here to use data and AI to bring more people to Marshmallow and give them a seamless, personalised experience from the moment they first hear about us. Our remit includes marketing optimisation, AI-driven personalisation across adverts, communications, product offerings, and the sign-up flow - along with automating onboarding to make every customer journey as smooth as possible.

We focus on high-impact work that directly improves customer conversion, helps us reach bigger audiences, and reduces costs and manual effort through smart automation. With end-to-end ownership and close collaboration across the acquisition team, we drive meaningful outcomes at pace.

We’re looking for a Senior Data Scientist to help take our acquisition strategy to the next level. You’ll have the opportunity to work across a range of impactful projects, from personalisation models and marketing optimisation to automating onboarding journeys. Success in this role will require a collaborative mindset, a passion for experimentation, and a strong interest in how AI can drive customer experience and business growth. We believe a proactive Data Scientist who’s eager to own and drive their area forward can make a huge impact here.

This is just the start of Data Science’s journey to be a key innovator at Marshmallow and in the wider insurance industry. We’re expanding our use of AI to create personalised experiences at scale, and we’re excited about the impact this can have on how people discover, understand, and join Marshmallow.

What You’ll Be Doing

  • Improving how we present our products to potential customers, with a focus on delivering a personalised sign-up experience that sets the standard in the industry and drives higher conversion rates.
  • Work within a cross-functional team (including engineers, designers, analysts, marketers, and product managers), taking ownership of projects end-to-end - from discovery through to production.
  • Use data to identify and quantify new opportunities, proactively shaping the acquisition team’s roadmap through idea generation, experimentation, and insight. As part of the Data Science function, you’ll also contribute to how we operate and evolve as a team.
  • Be a champion for data and AI adoption, helping to embed data-driven practices and a culture of impact within the team.
    Design and monitor A/B tests to measure the impact of initiatives.

Who You Are

  • You have a commercial mindset, focussed on delivering impact to the business as quickly as possible.
  • You can communicate clearly with people of all technical levels and disciplines.
  • You want to discover and scope new opportunities that may be uncharted territory.
  • You see the value in and push for solid data foundations, facilitating more complex analytics/ML projects.

What Were Looking For From You

Experiences that are essential

  • Experience building future-proof data models and analytics products.
  • Experience driving business action and impact from data-driven insights.
  • Leading projects end to end from a technical perspective.
  • Experience developing ML models to answer business cases.
  • Strong coding ability in Python, SQL.
  • Ability to manipulate large data sets.
  • At least 3-4 years commercial experience.

Experiences That Will Help You

  • Experience working in cross-functional teams.
  • Experience managing a team.
  • Experience in a high-growth company.

Perks of the job

  • Flexi-office working – Spend at least 3 days a week with your team in our new collaborative London office. The rest is up to you!
  • Flexible benefits budget - £50 per month to spend wherever you like on a Ben Mastercard.
  • Learning and development – Personal budgets for books and training courses to help you grow in your role. Plus 2 days a year - on us! - to further your skillset.
  • Mental wellbeing support – Access therapy and mental health sessions through Self Space, and sign up for your free subscription to Calm.
  • Equity – Get options in Marshmallow as part of your offer, and have a real stake in the company’s success.
  • Private health care - Enjoy all the benefits Vitality has to offer, including reduced gym memberships and discounts on smartwatches.
  • Medical cash plan - To help you with the costs of dental, optical and physio (plus more!).
  • Tech scheme - Get the latest tech for less.
  • Plus all the rest; 33 days holiday (including bank holidays), pension, cycle to work scheme, monthly team socials and company-wide socials every month!

Our process

We Break It Up Into 3 Stages

  • Initial call with Orla our Tech Talent Manager (30 mins).
  • A previous experience interview where you will discuss your journey so far and ways of working with Paul, our Head of Data Science (45 minutes).
  • A technical interview with one of our Senior Data Scientists (1 hr).
  • A culture interview with a bar raiser to see if your work style fits our processes and values (1 hour).
  • We’ll let you know if you’re invited to an interview or not. But, as a small team with a lot of applications to consider, we can’t give personal feedback on each application.

Everyone belongs at Marshmallow

At Marshmallow, we want to hire people from all walks of life with the passion and skills needed to help us achieve our company mission. To do that, were committed to hiring without judgement, prejudice or bias.

We encourage everyone to apply for our open roles. Gender identity, race, ethnicity, sexual orientation, age or background does not affect how we process job applications.

Were working hard to build an inclusive culture that empowers our people to do their best work, have fun and feel that they belong.

Recruitment privacy policy

We take privacy seriously here at Marshmallow. Our Recruitment privacy notice explains how we process and handle your personal data. To find out more please view it here.

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