Principal Backend Engineer

Joinhorizon; Greater London; On-site; GBP 120,000 - 180,000; Full time

Benefits offered by this job

Incentives and share options

Relocation support

Visa sponsorship

Job summary

Monzo is seeking a Principal Engineer to lead architectural direction for the company’s most complex systems. You will partner with engineering and product leaders to shape the technical and product roadmap, staying hands-on to maximize leverage.

You will mentor senior engineers and drive cross-team initiatives with a multi-year horizon. The role offers base salary discussions plus incentives and share options, with visa sponsorship and UK relocation support available.

Qualifications

• Proven track record leading complex, high-impact systems across multiple teams or domains.
• Strong ability to shape technical and product direction with engineering leaders.
• Hands-on coding and architectural leadership to influence leverage.

Responsibilities

• Partner with engineering and product leaders to shape Monzo's technical direction.
• Remain hands-on in coding and architecture where it adds leverage.
• Mentor senior engineers and develop future leaders within the engineering organization.

Skills

Go

AWS

GCP

Feast

Architecture

Job description

We’re on a mission to make money work for everyone.

We’re waving goodbye to the complicated and confusing ways of traditional banking.

With our hot coral cards and get-paid-early feature, combined with financial education on social media and our award winning customer service, we have a long history of creating magical moments for our customers!

We’re not about selling products – we want to solve problems and change lives through Monzo

London / UK Remote | This is a unique role, we’re open to discussions on base salary + incentive awards tied to your performance + share options + benefits |Technology

We have around 600 engineers out of roughly 5,000 people in total – and we have big ambitions. There are many interesting challenges ahead, and we’re happy for people to move between teams or to specialise, whatever you prefer. As an engineer here you’d be able to work directly with anyone across the company, and we run regular knowledge-sharing sessions so you’ll learn heaps about everything from how banks work to effective communication.

A Principal Engineer at Monzo is a hands on engineering leadership (IC) position. As a Principal Engineer you’ll:

• Partner with and guide Engineering and Product Leaders to shape the technical and product direction of Monzo, providing company-shaping leadership across collectives (100+ engineers) and driving alignment with company-wide priorities, owning problems that materially impact Monzo’s trajectory over the next 1-5 years.
• Remain hands-on in both coding and architecture where it adds the most leverage, especially in complex, high-risk or novel areas.
• Actively identifying high-leverage opportunities for Monzo and setting the direction of Engineering effort towards the most impactful outcomes.
• Mobilise teams across Monzo around high-impact problems, creating clarity, alignment and momentum, injecting urgency, or slowing things down to ensure safety and long-term sustainability.
• Lead and influence architectural direction for the most complex systems, driving consistency and reuse across domains, aligning local decisions with the broader system strategy.
• Set and uphold a high bar for technical excellence across Monzo, identifying and driving improvements in quality, reliability and scalability, and fostering a culture where engineers hold each other to that standard.
• Proactively mentor, sponsor and develop senior engineers and future leaders, multiplying your impact by enabling others to operate at a higher level.

What you’ll be using/ What you’ll be working on:

We rely heavily on the following tools and technologies:

• Go to write our application code (there’s an excellent interactive Go tutorial here )
• AWS for most of our production infrastructure and GCP for most of our data infrastructure.
• Feast for storing our features along a variety of tools to train and deploy models.

We’d love to hear from you if…

What’s in it for you

• You have a track record of leading complex, high-impact systems and driving technical direction across multiple teams, domains or business areas
• You think in multi-year horizons to look around corners and build for the future, identifying opportunities before they present themselves
• You combine strong technical judgment with product and business awareness, making pragmatic trade-offs
• You’ve worked on large scale backend, distributed or data-intensive systems
• You’re comfortable operating in ambiguous problem spaces, helping teams define direction and execute
• You influence and align the most senior stakeholders across engineering, product and beyond
• You care about outcomes and impact, using data to guide decisions and to iterate
• You enjoy mentoring and raising the bar for other engineers

This is a unique role, we’re open to discussions on base salary + incentive awards tied to your performance + share options + benefits

We’ll help you relocate to the UK.

We can sponsor your visa.

This role can be based in our London office, but we’re open to distributed working within the UK (with ad hoc meetings in London)

We offer flexible working hours and trust you to work enough hours to do your job well, and at times that suit you and your team.

£1,000 learning budget each year to use on books, training courses and conferences.

We will set you up to work from home; all employees are given Macbooks and for fully remote workers we will provide extra support for your work-from-home setup.

The application journey has 4 key steps

Our interview process involves four main stages after an informal recruiter call:

• Initial Call
• System Design Interview
• Take home task or pair coding exercise
• Final interview including a behavioural and a leadership interview

This process should take around 3-4 weeks – your schedule is really important to us, so we promise to be as flexible as possible!

One of our engineers has written a detailed blog on their experience through this process, for extra details, hints and tips please see here .

#LI-ZM

Equal opportunities for everyone

Diversity and inclusion are a priority for us and we’re making sure we have lots of support for all of our people to grow at Monzo. At Monzo, we’re embracing diversity by fostering an inclusive environment for all people to do the best work of their lives with us. This is integral to our mission of making money work for everyone. You can read more in our blog , 2024 Diversity and Inclusion Report and 2024 Gender Pay Gap Report.

We’re an equal opportunity employer. All applicants will be considered for employment without attention to age, ethnicity, religion, sex, sexual orientation, gender identity, family or parental status, national origin, or veteran, neurodiversity or disability status.

If you have a preferred name, please use it to apply. We don’t need full or birth names at application stage