Senior Backend Engineer

Monzo

🚀 We’re on a mission to make money work for everyone. We’re waving goodbye to the complicated and confusing ways of traditional banking. After starting as a prepaid card, our product offering has grown a lot in the last 10 years in the UK. As well as personal and business bank accounts, we offer joint accounts, accounts for 16-17 year olds, a free kids account and credit cards in the UK, with more exciting things to come beyond. Our UK customers can also save, invest and combine their pensions with us.  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 | 💰 £155,000 - £200,000 + Equity | Benefits | Technology  Senior Staff Engineer: L70 on our Engineering Progression Framework About our Engineering Teams: 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. We contribute to open source software as much as possible. Our blog is a good place to learn even more about what we do. Senior Staff Engineer Responsibilities: A Senior Staff Engineer at Monzo is a hands on engineering leadership (IC) position. As a Senior Staff Engineer you’ll: * Partner with Engineering Directors to shape the technical and product direction of a collective, providing leadership across multiple squads (30–70+ engineers) and ensuring alignment with company-wide priorities. * Be hands on in both coding and architecture, leading from the front. * Partner closely with Product and Design leadership to define strategy, shape roadmaps, and make high-quality trade-offs that maximise business and customer impact across the collective. * Mobilise teams across your collective around high-impact problems, creating clarity, alignment and momentum, injecting urgency when needed, or slowing things down to ensure safety and long-term sustainability. * Lead and influence architectural direction for the most complex systems, ensuring cohesive, scalable designs across multiple teams and aligning local decisions with the broader system strategy. * Set and uphold a high bar for technical excellence across the collective, 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) * Cassandra for most persistent data storage * Kafka for our asynchronous message queue * Kubernetes and Docker to schedule and run our services  * AWS for most of our production infrastructure and GCP for most of our data infrastructure. * React for internal Web dashboards * Feast for storing our features along a variety of tools to train and deploy models. 🤩We’d love to hear from you if…  * You have a track record of leading complex, high-impact systems and driving technical direction across multiple teams * You combine strong technical judgment with product and business awareness, making pragmatic trade-offs * You’ve worked on scalable backend, distributed or data-intensive systems * You’re comfortable operating in ambiguous problem spaces, helping teams define direction and execute * You influence and align senior stakeholders across engineering, product and beyond * You care about outcomes and impact, using data to guide decisions * You enjoy mentoring and raising the bar for other engineers How we work 💻 Locations & Flexible Working:  Our main tech hub is in London, but our engineers live everywhere in the UK— from Brighton to the Western Isles.  We value meeting in person but we don't have a mandated requirement on office attendance, even if you're nearby. We believe you'll do your best work if you are where you want to be. If you live outside of London and we ask you to come into the office, Monzo will support you with the costs. ✨ Our offices are naturally social, especially Tuesdays, Wednesdays and Thursdays, which happen to line up with our twice-weekly Monzo lunches & treat Thursdays 🍽️. Teams also schedule time together often for work and play – in or around the office, or online. Set up a work schedule that delivers impact and fits your life: At Monzo, we value connections, flexibility, and wellbeing. We keep our meetings during core hours to stay connected and believe in maintaining work/life balance.  You’ll be empowered to manage your work in a way that suits you and your team, giving you the freedom for children drop-offs and pick-ups, walking your dog or adventurous cat, avoiding peak commuting times or gym slots, appointments, or supporting your family in an emergency. 🕒✨ If you prefer to work part-time, we'll make this happen whenever we can - whether this is to help you meet other commitments or strike a great work-life balance. Work the way that works for you with Monzo! 💼 🙌What’s in it for you 💰 Base salary £155,000 - £200,000 + Equity ✈️ 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.  ➕ Plus lots more! Read our full list of benefits. 🌈 The application journey has 4 key steps Our interview process involves four main stages after an informal recruiter call:  1. Recruiter Call  2. Initial Call  3. System Design Interview  4. Take home task or pair coding exercise  5. 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 staff engineers has written a detailed blog on their experience through this process, for extra details, hints and tips please see here. #LI-Remote #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, 2026 Diversity and Inclusion Report and 2025 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 😊

Monzo

🚀 We’re on a mission to make money work for everyone. We’re waving goodbye to the complicated and confusing ways of traditional banking. After starting as a prepaid card, our product offering has grown a lot in the last 10 years in the UK. As well as personal and business bank accounts, we offer joint accounts, accounts for 16-17 year olds, a free kids account and credit cards in the UK, with more exciting things to come beyond. Our UK customers can also save, invest and combine their pensions with us.  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 | 💰Senior Engineer £95,000 - £130,000  +  Incentive Awards tied to your performance  Benefits | Technology - Engineering | About Platform Engineering at Monzo: The Platform Collective builds and maintains the infrastructure, tools and processes that sets the rest of Monzo technology teams up for success. We work on a wide range of shared infrastructure, services and engineer tooling. The Infrastructure Platform team sit within the Platform Collective and are responsible for running the Kubernetes clusters, service mesh and networking that all of Monzo's microservices run on. Our team is made up of backend engineers and cloud infrastructure experts, using our experience and software engineering skills to solve problems and manage our cloud infrastructure.   Our Infrastructure Platform team Has Two Focus Areas * We build and centrally manage the cloud infrastructure that underpins technology at Monzo, running components like Kubernetes and Envoy across AWS and GCP. * We help other platform teams to succeed at using cloud infrastructure by abstracting away the complexity and enabling them to solve real customer problems We’re investing heavily in this team to support Monzo’s ambitions to grow from 10 to 20 million customers, expand the range of products to improve our customers’ financial lives and set up the foundations for scaling Monzo across the globe.   How we work 💻 Locations & Flexible Working:  Our main tech hub is in London, but our engineers live everywhere in the UK— from Brighton to the Western Isles.  We value meeting in person but there’s no pressure to come into the office, even if you're nearby. We believe you'll do your best work if you are where you want to be. If you live outside of London and we ask you to come into the office, Monzo will support you with the costs. ✨ Our offices are naturally social, especially Tuesdays, Wednesdays and Thursdays, which happen to line up with our twice-weekly Monzo lunches & treat Thursdays 🍽️. Teams also schedule time together often for work and play – in or around the office, or online. What you’ll be working with: As a Platform Engineer at Monzo, you will work across the full breadth of our core infrastructure and application platform. This role involves a balanced split of responsibilities between two critical areas: 1. Platform & Infrastructure Engineering: Enhancing and maintaining our foundational tools and systems. * Working hands-on with our Kubernetes clusters, AWS infrastructure, and configuration management using Terraform. * Integrating and managing various open-source components to provide robust, scalable primitives for our engineering teams. 2. Software & Backend Engineering: Building and maintaining the services that abstract and orchestrate our infrastructure. * Designing and implementing backend services (APIs, controllers, etc.) that provide a simplified, self-service experience for other engineers. * Developing software for complex projects like infrastructure migrations, high-scale traffic management, or security tooling.   We rely heavily on the following tools and technologies, please note direct experience in these technologies is not required and our interview process can be completed in any language: * Go to write our application code (there’s an excellent interactive Go tutorial here), in platform we build services to manage parts of the platform * Kubernetes most workloads we run are on Kubernetes with this team being responsible for the underlying cluster's management * AWS and GCP whilst our primary platform is in AWS our footprint in GCP is continually growing and we are increasing our maturity across both of these platforms * Terraform is primarily how we manage any resources deployed into the cloud * Envoy Proxy for our RPC service mesh 🤩We’d love to hear from you if… To succeed in this role, you will need a strong background in both modern platform tooling and practical software development. * Software Engineering Foundation: You have significant professional experience in software engineering, demonstrated by writing, testing, and deploying robust backend services using strongly typed languages. * Cloud & Container Experience: You have hands-on experience working with AWS and/or GCP, and you are proficient with Kubernetes. * Automation & Infrastructure as Code: You are naturally inclined to solve problems through automation and have experience with Infrastructure as Code (e.g., Terraform). * System Curiosity: You are deeply curious about systems, enjoy diving deep to investigate complex issues, and understand how modern distributed applications fail and scale. * Platform Mindset: You'd be excited to build a platform that enables success for everyone at Monzo, focusing on reliability, performance, and developer experience. * Comfort with Ambiguity: You're comfortable working in a fast-paced team that deals with ambiguity and evolving requirements.   We're on the look out for L40 & L50 Platform Engineers at the moment, you can read more in our Engineering Progression Framework  The Interview Process: Our interview process involves three main stages:  1. Initial Call  2. Take home task or pair coding exercise  3. Final interview: including a system design and a behavioural interview  Our average process takes around 4 weeks but we will always work around your availability.  One of our engineers has written a detailed blog on their experience through this process, for extra details, hints and tips please see here. What’s in it for you: 💰 £95,000 - £130,000 base salary➕  Incentive Awards tied to your performance ✈️We can help you relocate to the UK  ✅We can sponsor visas. 📍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, at times that suit you and your team. 📚Learning budget of £1,000 a year for books, training courses and conferences ➕And much more, see our full list of benefits here  #LI-Remote #LI-HJ1 ---------------------------------------------------------------------------------------------------------------------------------- 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, 2026 Diversity and Inclusion Report and 2025 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 😊

Monzo

🚀 We’re on a mission to make money work for everyone. We’re waving goodbye to the complicated and confusing ways of traditional banking. After starting as a prepaid card, our product offering has grown a lot in the last 10 years in the UK. As well as personal and business bank accounts, we offer joint accounts, accounts for 16-17 year olds, a free kids account and credit cards in the UK, with more exciting things to come beyond. Our UK customers can also save, invest and combine their pensions with us.  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/Cardiff/UK Remote | 💰 £93,000-120,000 + Incentive Awards tied to your performance + benefits | Hear from the team ✨  About us: At Monzo we want to make money work for everyone. We care deeply about our 15+ million customers. Through magically simple products and actionable insights, we put our customers in control of their finance. Our products are different by design, and reliable at our core. Our range of borrowing products are critical to Monzo’s mission. Not only do they serve important needs of our customers, they are also a key revenue driver to support Monzo keep delivering great products and experience. We have seen stellar growth and deep engagement with millions of borrowers, supported by effective and efficient credit risk management. Our product portfolios are still expanding fast, from personal to business credit, and markets beyond UK. We are looking for bright, passionate and creative individuals to further accelerate our growth. About the role The mission of Borrowing ML Scientists is to improve the customer and business outcomes through better automated decisioning, using Machine Learning and Statistical modelling. We have a primary focus in credit risk modelling, with our expertise also applied to predict and optimise utilisation, pricing, collection and marketing. You will be working alongside a team of very experienced and highly efficient ML Scientists, with well established toolings for the fully lifecycle of ML models. Each of you owns multiple ML applications end-to-end, from experiment design and data curation, to deployment and monitoring. You will be empowered to innovate in the data, methodologies and toolings, so we can build better models easier and faster. You will have exposure to all Borrowing products and applications, with autonomy to decide what are the most impactful topics to work on, and how to deliver them. You will work closely with our Credit Strategy Managers, Model Validation Analysts, Backend Engineers, and Product Managers, to fit your model development into the product roadmap. You are also empowered to think big about the business, market and customers, to influence our product and credit strategy beyond just the world of models. Our technology stack We rely heavily on the following tools and technologies (although we do not expect applicants to have prior experience of all them): * Google Cloud Platform for all of our analytics usages * BigQuery SQL and dbt for our data modelling and warehousing * PyData stack for model development and offline deployment * Google Vertex AI platform for cloud computing * AWS for backend infrastructure * Python for ML model microservices * Go lang for most other microservices * AI toolings for productivity (an evolving list) * Google suites including access to Gemini * ChatGPT enterprise * Claude code 🤩 You should apply if: * You are result oriented and motivated by the impact on our customers and business * You enjoy a high degree of autonomy and thrive in a fast-paced environment * You are keen to grow your knowledge in both business and technology 📌 You must have: * Excellent SQL and Python skills with good understanding of best practices in software engineering and data engineering * In-depth knowledge of statistical and machine learning models: gradient boosted trees, logistic regression, neural networks, survival analysis, etc * Solid knowledge of statistics: hypothesis testing, confidence intervals, bootstrap * Experience of end-to-end model development and maintenance of ML models used for business critical automated decisioning, in a consumer facing industry * Great attention to details while keeping an eye on the big picture * Excellent communication skills to articulate complex problems * Capability to build mutual respect and trust with people of different background Nice to have: * Experience in UK/EU retail lending businesses for personal/business customers * Experience of ML model governance in a regulated industry * Experience in leverage modern day AI tools for productivity The Interview Process: Our interview process involves: * 30’ Recruiter Call * 45’ Initial Call * 60’ ML technical skill interview * 60’ Behavioural interview All interviews will be conducted through Google Meet. What’s in it for you: 💰 £93,000 to £120,000 ➕ plus stock options & benefits ✈️ We can help you relocate to the UK ✅ We can sponsor visas 📍This role can be either based in our London office with hybrid working pattern, or fully remote within UK with occasional travels to London. 🏡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. ⏰ We offer flexible working hours and trust you to work enough hours to do your job well, at times that suit you and your team. 📚 Learning budget of £1,000 a year for books, training courses and conferences ➕ And much more, see our full list of benefits here #LI-DC2  #LI-Remote   ---------------------------------------------------------------------------------------------------------------------------------- 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, 2026 Diversity and Inclusion Report and 2025 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 😊