Our portfolio companies are always looking for great people. Apply to the opportunities below or send us your profile.

Backend Engineer, Ruby at Cleo AI
London, GB


Cleo is an AI assistant that helps over 600,000 people in the UK, US and Canada feel great about their money. We are a fast-growing start-up, backed by the founders of Skype, Transferwise and Zoopla.

We're looking for software engineers to help us deliver product at scale. You'll work within a bright, experienced backend team of 6 engineers and a wider engineering team of 10, which we're growing to 20+ over the next year.

What you’ll be doing:

Projects are undertaken over 2-week long sprints with sprint goals aligned to overall quarterly targets.

Some of our current interests lie in:

  • Machine learning: we have a wealth of user transaction data that we are leveraging, using ML techniques, to provide better insights to our users.
  • Scaling to a million users: we need to ensure that our tech stack can support our ambitious growth targets over the next 12 months. We are working on optimising our rails application for performance and memory usage, and scaling our database.
  • Product: working on an intelligent assistant used by hundreds of thousands of people offers unique challenges and opportunities compared to your standard web application. We’re constantly iterating based on user feedback to provide the best experience to our users.

Our Stack:

  • Ruby on Rails
  • Minitest
  • Sidekiq
  • React
  • Postgres
  • Redis
  • Heroku
  • Github
  • CircleCI


About you:

  • You are a Ruby developer with at least 2 years’ experience in a backend role.
  • You can reduce complex problems to simple solutions consistently.
  • You enjoy making those around you better engineers.
  • You are excited by what we're building at Cleo; you are product-focused and care about making our users’ lives better.

Advantageous, but not essential;

  • Experience with React.
  • Experience scaling platforms growing at pace (Postgres / Rails).


Our process:

  1. Quick phone call with a member of our engineering team to find out more about your experience and why you want to work at Cleo.
  2. Short take-home test.
  3. Onsite interview:
    1. Technical discussion with a senior engineer.
    2. Pairing on an interesting problem.
    3. Meet the CEO and COO.


Cleo is a great place to work:

  • An above market compensation package (Base + Equity). We're prepared to pay for the very best.
  • Work at one of the fastest growing tech startups anywhere in the world. We recently closed a competitive Series A with Balderton who join a formidable investor base including the founders of Skype, Transferwise, Zoopla, Lovefilm, Climate corporation, SongKick and others.
  • The team is exceptional. You'll get to work with brilliantly bright and dedicated individuals every day.
  • Our mission is unique. We want to radically improve everyone’s relationship with money. We're not maximising the time consumers spend in a feed, getting fast food delivered, or building an incrementally better bank. We're changing an industry in a visceral way, which you get to see every day in our customer feedback.

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