Senior Backend Product Engineer - London, UK

About SequenceJoin Sequence and play a pivotal role in developing a revolutionary platform that facilitates seamless payment solutions for businesses. With over $1 billion in annual invoice processing and a trajectory of rapid growth, we are at the forefront of transforming financial operations.Our AI-powered revenue platform is designed specifically for modern finance teams, replacing outdated spreadsheets and cumbersome legacy systems with intuitive software that enhances performance and user satisfaction.Trusted by over 100 high-growth companies, including Cognition, incident.io, and MoonPay, we manage the entire revenue cycle, from quoting to billing and revenue recognition.Founded by a team of seasoned entrepreneurs, we achieved an impressive 10x ARR growth last year and recently secured a $20M Series A led by 645 Ventures, along with contributions from a16z and remarkable founders and CFOs from notable companies like Decagon, Klaviyo, and Wise.What’s it like to work at Sequence?We offer a small team environment with vast opportunities for impact and ownership. You will engage in meaningful work, gain direct access to customers, and develop alongside a rapidly growing company.If you’re ready to elevate your career at a fast-scaling company, we’re eager to connect with you.Your RoleWe are deeply committed to the quality of our product and are seeking passionate engineers who take end-to-end ownership—from conception to delivery and ensuring that our solutions meet customer needs.Here are some projects you may contribute to:Developing AI-Driven Approval Workflows. Create flexible, customizable approval chains that adapt to various business rules, enabling customers to define workflows in natural language.Creating an Intelligent Collections Agent. Design an automated agent that manages payment reminders and escalations through natural language instructions.Scaling Billing Infrastructure. Redesign our billing pipeline to handle significant increases in throughput while optimizing costs and storage strategies.As part of our lean team, you will have the opportunity to significantly influence our engineering practices and product direction.

Join Our Vision! At Uncapped, we empower ambitious founders to scale their businesses through innovative financing solutions. We champion curiosity, continuous improvement, and impactful problem-solving.Technologies You Will Work With Core Technologies: Java 21, Spring Boot/Cloud 3.3Infrastructure: GCP, KubernetesDatabase Technologies: SQL/NoSQL (chosen per use case)Your Contributions Design and develop secure microservices tailored for financial systems.Take ownership of services throughout their lifecycle (design → deploy → monitor).Enhance code quality through automation and modern practices (CI/CD pipelines in under 15 minutes).Stay at the forefront of technology and share your insights with the team.Excel within a Kanban-driven team that values effective communication over meetings.Why Choose Uncapped?Be part of a fintech solution trusted by thousands of businesses.Contribute to a product that you can help shape and significantly impact.Supported by leading venture capitalists like LakeStar and SeedCamp.

Role overview Xero Limited is seeking a Senior Engineer to join its UK Regional Team, based in London at 7 Devonshire Square. This position focuses on shaping features for the UK market, connecting technical work directly to customer needs and business outcomes. Senior Engineers at Xero handle complex challenges that span multiple products, balancing regional requirements alongside global strategy. Team structure and collaboration The team includes an Engineering Manager, Lead Engineers, and Engineers, all reporting to the General Manager of Engineering for the UK. Collaboration is a core part of the role. Senior Engineers work closely with product owners and peers across Xero, designing, building, and delivering solutions that have real impact. Projects and technical scope Current projects span the full Xero platform, including Payments, Accounting, and Payroll. This role provides exposure to a broad range of products and technical domains within Xero’s suite. Work environment Xero holds a Great Place to Work UK accreditation. Flexible work arrangements are available: choose remote, hybrid, or office-based work in London, Milton Keynes, or Manchester. Offices are designed to support collaboration and connection. Some travel may be needed to coordinate with global teams and support international partnerships. Requirements Curiosity and drive to solve customer problems, delivering clear business value across technical areas Adaptability in learning new domains and navigating unfamiliar codebases Ability to work with stakeholders and build consensus across distributed teams Commitment to high-quality engineering practices, producing scalable and maintainable code Comfort in high-visibility situations, using strong communication to engage stakeholders and broaden influence Experience with modern programming languages and frameworks, along with a solid understanding of software engineering fundamentals

Join Aircall, a revolutionary unicorn in the AI-powered customer communications sphere, trusted by over 22,000 companies globally to enhance revenue, expedite issue resolution, and empower customer-facing teams. We are transforming the landscape of customer communications by integrating voice, SMS, WhatsApp, and AI into a unified workspace.Our growth is driven by a straightforward principle: to enable teams to work smarter, not harder. Our AI Voice Agent automates routine calls, while AI Assist simplifies post-call tasks, and AI Assist Pro provides real-time insights, allowing individuals to excel in their roles. This synergy results in increased revenue, quicker resolutions, and scalable teams.Headquartered in Paris, with a solid presence in North America anchored in Seattle, Aircall also has teams in vibrant cities such as Madrid, London, Berlin, San Francisco, New York City, Sydney, and Mexico City. Our product is beloved by customers, and we are rapidly scaling, supported by top-tier investors and continuous AI advancements across multiple product lines.At Aircall, you'll become part of a dynamic company. We are ambitious, focused on product development, and execution-oriented, with a clear impact, swift decision-making, and genuine growth opportunities.Our Work Culture at Aircall: We prioritize customer satisfaction, leverage data for decision-making, and are dedicated to delivering significant outcomes. We cherish ownership, continuous improvement, and thoughtful agility. If you thrive in a collaborative, fast-paced environment where trust and impact are essential, you will thrive here.Position Overview:As a Senior Backend Software Engineer, you will take charge of designing, developing, deploying, and maintaining essential features that enhance customer value on our voice platform.You will be expected to advocate for best practices, mentor team members, and contribute to the broader Engineering community as part of your daily responsibilities.Quality, excellence, and agility are at the core of our delivery process, and you will play a pivotal role in elevating these standards.Utilizing a diverse array of backend technologies tailored to specific needs, all hosted on AWS, we create resilient services that deliver added value on top of voice while fully integrating with our customers' critical business tools (CRM, Helpdesk, E-Commerce, etc.).

Role overview As a Senior Product Engineer at goodstack in London, the focus is on building and refining products that have a clear impact for users. This position plays a key part in shaping features that deliver reliable performance and meaningful experiences. Working closely with colleagues from various teams, the Senior Product Engineer helps turn ideas into well-crafted solutions. What you will do Design and implement new product features, prioritizing user experience and strong performance Work with cross-functional teams at every stage of development Refine current features in response to feedback and changing needs Contribute to keeping goodstack’s products relevant as technology evolves Location This role is based in London, UK.

About 9fin9fin is a cutting-edge AI platform revolutionizing the global debt markets, which represent the largest asset class exceeding $145 trillion.The landscape of debt markets is extensive, global, and essential, yet it often relies on disjointed data, PDFs, and manual processes. 9fin transforms this outdated infrastructure by providing a unified platform that consolidates proprietary credit data, in-depth analysis, and efficient workflows across international markets.Currently, 9fin empowers over 300 prestigious institutions worldwide, including leading banks, asset managers, private equity firms, law firms, and consulting advisors. The company is experiencing rapid growth, particularly in the US, with exceptional retention rates driven by robust workflow adoption.We are at a pivotal moment. With a validated product-market fit and strong global demand, 9fin is propelling towards becoming the definitive platform for debt markets globally.What You'll Work OnAs a Senior Backend Engineer on our Structured Credit team, you will contribute to the development of our market-leading CLO product and assist in the launch of a new vertical.Our team is dedicated to making a significant impact, leveraging technology to create value for the business. While we have overarching business goals, we enjoy the autonomy to define our team objectives and determine our success metrics. We uphold accountability and proactive behaviors such as ownership.Lead projects within a cross-functional team by defining and designing systems, building proof of concepts, and delivering new service functionalities—including APIs, data processing, and automation—while collaborating with Product and Clients.Engage in backend development and engineering primarily on the services and web applications hosted on the 9fin platform.Play a crucial role within project teams as a senior individual contributor, conducting code reviews, mentoring fellow developers, and participating in early research and experimentation with new technologies to provide insights for new features and products.Continuously enhance the 9fin codebase by seizing opportunities to automate, refactor, and document processes when it has the most significant impact.Work across diverse web platforms involving complex financial data modeling, intricate access control logic, environmental data capture, integration of ML/AI prediction services, and data visualization.

At Plain, we are revolutionizing customer support for the modern B2B landscape. Our aim is to develop the most rapid and powerful platform, enabling companies to transcend traditional reactive support and foster genuine customer relationships.Renowned companies such as Cursor, Raycast, and Granola trust Plain to consolidate their customer interactions, enhance team collaboration, and elevate their workflows through the integration of AI.The B2B customer support sector is experiencing a monumental transformation, with AI redefining customer engagement. Support is evolving from a siloed function to a collaborative effort across platforms like Slack, Discord, and other communication channels. The outdated methods of slow, manual, and fragmented processes are no longer viable.This position offers a hybrid work model, requiring 3 days a week in our London office.Key ResponsibilitiesWorking at Plain involves more than just managing tasks; it encompasses owning and addressing challenges comprehensively—from infrastructure decisions to feature design and user interface elements.In this role, you will:Influence Product Strategy: Contribute to the technical architecture and product roadmap, effectively balancing customer insights with long-term product sustainability.Deliver Features from Concept to Launch: Define, develop, and deploy product features that directly address customer needs. Teams include:Core Product Team: Manage all customer-facing channels (Slack, Discord, Email, etc.), core data models, and customer requests while balancing rapid execution with foundational integrity.Developer Infrastructure Team: Create the essential tools that empower every engineer at Plain to effectively deliver and maintain the product, with a focus on optimizing team speed and minimizing obstacles.Enhance Backend Architecture: Tackle some of our most intricate challenges, from data modeling to high-performance reporting, establishing standards for our development processes.Optimize Developer Experience: Ensure that Plain is not only user-friendly but also developer-friendly, from data pipelines to APIs.

About MetaviewMetaview is dedicated to eliminating toil in the workplace. We believe that toil hinders progress, much like friction impedes motion. Our innovative solution is found in Human-Computer Symbiosis.With the introduction of AI copilots, the way we work is set to transform:Encouraging a flow state while minimizing toil.Enhancing insight while reducing guesswork.Focusing on human-centricity rather than process-centricity.Metaview serves as the AI copilot for hiring processes.Founded in April 2018 by Siadhal and Shahriar, who left their roles at Uber and Palantir, respectively, to address their own challenges in product and team development. Today, we empower thousands of users at leading companies such as Quora, Robinhood, Brex, Elastic, and Replit.Our team is small, high-performing, and fast-paced, with a relentless focus on delivering exceptional work.

Join commercetools as a Senior Backend Engineer, where you will play a pivotal role in shaping innovative backend solutions using TypeScript. Collaborate with cross-functional teams to create scalable and resilient microservices that empower our clients to deliver exceptional digital commerce experiences.

About the CompanyAffinidi is a pioneering technology firm focused on reimagining data ownership. We empower both businesses and individuals to take control of their data, providing a holistic approach to managing their digital identity while prioritizing privacy and security.Our innovative technology facilitates decentralized digital identity solutions, ensuring that everyone has the right to own and govern their data. We are dedicated to establishing a trustworthy ecosystem for digital credentials that allows secure data and service exchange across various sectors and borders. About the Role: We are seeking a solution-driven Senior Backend Engineer who possesses substantial expertise in Rust. The ideal candidate will have a track record of delivering robust backend solutions and is eager to contribute to our mission of transforming digital identity.

Join Attio in Revolutionizing CRM for the AI Era!At Attio, we are dedicated to transforming customer relationship management by creating the first AI-native CRM tailored for ambitious go-to-market teams. Our recent funding of $52M Series B, led by GV (Google Ventures) with contributions from Redpoint, Balderton, Point Nine, and 01A, enables us to tackle complex technical challenges and elevate industry standards.Your RoleAs a Senior Product Engineer on our dynamic Engineering team, you'll be at the forefront of innovation, addressing real-time infrastructure and architecting AI-native systems. Your contributions will ensure our users enjoy an effortless experience, all while maintaining our high standards for performance, reliability, and security.Key ResponsibilitiesUtilize your expertise in TypeScript, Node.js, and GCP to drive product advancements.Lead projects from inception to completion, resolving genuine customer challenges.Architect systems that support new features and optimize existing ones to meet scaling demands.Design intuitive REST API contracts for both internal and external users.Champion Attio’s Product & Engineering values within and beyond the organization.QualificationsProven experience in designing scalable, reliable, and secure backend systems.In-depth knowledge of modern Cloud Native architecture.Expertise in Node.js and TypeScript.A strong track record of ownership and successful product delivery.A proactive and self-driven approach to problem-solving, with a passion for innovation in distributed systems.Exceptional communication skills to convey technical concepts to diverse stakeholders.

Join Three UK as a Senior Counsel specializing in Regulatory Implementation, where you will play a pivotal role in navigating the complexities of telecommunications regulations. Your expertise will ensure compliance and drive strategic initiatives in regulatory matters.

Join Our Dynamic Team at XapienAt Xapien, we empower businesses to truly understand their connections with suppliers, investors, partners, and third parties. Our innovative approach merges speed, scale, and precision, utilizing advanced AI technology.Since our inception in 2018, we've evolved from a deep-tech startup to a key player in AI-driven due diligence and risk intelligence. The year 2024 marked a significant milestone, with the successful closure of a $10M Series A funding round and accolades in the Chartis RiskTech100® and Everest Group’s Leading 50™. Our expansion has led to a broader product range, new market entries, and an expanding customer base.Our Growth TrajectoryWe're witnessing accelerated demand across various industries, especially in wealth management, financial services, and supply chain onboarding, extending our reach beyond the UK to customers in the Middle East, Asia, and Oceania.Why Now is the Perfect Time to Join UsThis position is not just another role; it’s a chance to influence the future of the due diligence sector with a market-leading product that organizations worldwide trust. Whether your expertise lies in marketing, communications, sales, or finance, your contributions will be vital in driving growth, enhancing credibility, and connecting our product with a swiftly changing market.As we scale rapidly, with an increasing number of customers and product releases, we face larger regulatory and market challenges. The expectation for real-time insights in due diligence is higher than ever. Your role will go beyond routine tasks; you will be shaping strategy, refining processes, and positioning a brand that is redefining trust and transparency.If you're passionate about learning, innovating, and making a meaningful impact, now is the time to join Xapien.The RoleWe are seeking a skilled Senior Backend Engineer to take on a pivotal technical leadership role within our engineering team. You will tackle our most complex technical challenges, take ownership of critical components within our platform’s architecture, and help guide our technical direction to ensure we continue to stay ahead in the industry.

About UsAre you ready to embark on a thrilling challenge?At XYZ Reality, a dynamic and award-winning Series-A startup, we're on a rapid ascent toward our next funding milestone. Our vision is to revolutionize the construction sector by enhancing our platform's features, performance, and scalability.We thrive in a fast-paced, multi-disciplinary environment, engaging in various domains such as cloud development, electronics, embedded software/hardware, mechanical design/manufacturing, AI & computer vision, and data science—all contributing to our innovative BIM Platform.To propel this mission forward, we are in search of a Backend Engineer with extensive Node.js experience to assist in our transition from Java to Node.js and develop high-performance, scalable backend services. You will collaborate closely with our API development, client applications, and data pipeline teams to design and deliver robust, efficient solutions.Our office is situated in central London, just a short stroll from Angel Station.

We are seeking an experienced and passionate Senior Backend Engineer specializing in TypeScript to join our dynamic software engineering team at onrunning. In this pivotal role, you will lead the design and development of robust backend systems that power our innovative applications. You will collaborate closely with cross-functional teams to deliver high-quality solutions that meet the needs of our users. If you have a strong background in backend development, a love for building scalable systems, and a desire to drive technical excellence, we want to hear from you!

Join Our TeamAt Tracer, we are pioneering the development of autonomous AI agents designed to enhance production data pipelines. As a venture-backed startup, we are supported by a network of seasoned investors and industry leaders who share our vision of transforming AI into a critical component of enterprise software in the coming decade. Our compact team is composed of experienced professionals dedicated to delivering impactful solutions. Role OverviewWe are on the lookout for a Founding Senior Backend Engineer based in London. In this pivotal role, you will take ownership of building the core systems that convert production alerts into actionable root cause analyses (RCAs) and effective fix recommendations, targeting a select few high-value alerts.This position merges backend engineering with product development and customer-centric problem-solving, aiming to alleviate real-world production challenges with robust, reliable systems that engineers can depend on. Our Tech StackPython + LangGraph for multi-agent alert investigationRust for high-performance systemsClickHouse for managing high-volume event data and investigation historiesAWS + Terraform for self-sustaining infrastructureNext.js + TypeScript for an engaging frontend experience Key ResponsibilitiesAs the Founding Senior Backend Engineer, you will:Design and build the foundational alert, investigation, and root cause analysis (RCA) pipeline using Python.Develop essential systems including:Alert ingestion and normalizationContext enrichment and correlationProblem framing outputsHypothesis orchestration engineInvestigation execution runtimeInvestigation artifacts and reportingLead architectural decisions ensuring the system's observability, auditability, and reliability from day one.Work closely with the founders to deliver a focused set of high-impact alert types, while strategically expanding coverage.Create customer-ready documentation and reports that enhance user understanding and trust in the system.

Affinidi develops technology that helps people and organizations manage their data with greater control. The team designs digital identity tools that keep privacy and security at the forefront. Their work emphasizes decentralized approaches, aiming to make digital credentials both secure and accessible across industries and borders. Role overview The Senior Backend Engineer (Rust) position focuses on building and refining backend systems for privacy-first digital identity products. This London-based role plays a key part in supporting secure, reliable services that underpin Affinidi's core offerings. What you will do Develop and maintain backend services using Rust Create technical solutions that enhance efficiency and reliability Support the ongoing development of decentralized identity platforms Location London, England, United Kingdom

Join V7 LabsAt V7 Labs, we're revolutionizing the AI landscape by creating platforms that empower individuals to achieve peak performance with unmatched efficiency. Our goal is to convert human expertise into reliable AI, streamlining complex processes to be quicker, smarter, and more precise. We are experiencing rapid growth, supported by top investors and AI visionaries, including the creators behind Transformers and Gemini.Your RoleAs a Product Engineer, you will contribute to V7 Go, a platform designed to equip legal, finance, insurance, and accounting sectors with a customizable no-code AI agent toolkit. This tool focuses on harnessing multi-modal data to produce verifiable outputs while ensuring transparency in AI logic for accuracy and compliance.V7 Go integrates the latest models, including GPT-5, Claude 4.1, and Gemini 2.5, ensuring optimal accuracy and performance. Check out the V7 Go keynote for more insights into our innovative solutions.Team Dynamics and ImpactYou will report directly to Chris, our Engineering Manager, and collaborate within the Go Engineering team.Working alongside a dedicated team of up to 7 professionals, you will take on significant responsibilities encompassing coding, testing, planning, and analysis.You will have the autonomy to establish your own objectives, strategies, and metrics, emphasizing impactful outcomes rather than mere task completion.We value proactive engineers who take ownership of their work, demonstrating initiative in problem-solving and collaboration.Your Day-to-Day ResponsibilitiesFacilitating the application of foundational models to scale multi-modal data.Enhancing our platform to effectively manage complex multi-tenant usage patterns.Developing a comprehensive suite of APIs to support both our internal systems and customer-facing products.Delivering production-ready updates multiple times daily, collaborating closely with Product and Design teams to address customer needs.Candidate ProfileExperience in functional programming is essential. Familiarity with Elixir is advantageous, but languages such as Scala, GoLang, Node.js, Haskell, Clojure, and F# are also welcomed.Strong problem-solving skills and a proactive attitude towards challenges.

Join Apron as a Senior Software Engineer - BackendAt Apron, our mission is to empower small and medium-sized businesses by ensuring their success. We understand that cash flow challenges often stem from the pressure of demand payments on business owners, which can hinder their ability to meet these obligations.We are bridging this gap by modernizing and simplifying the payment processing experience: from capturing invoices to issuing expense cards, and facilitating transactions—all in one seamless platform.As a rapidly growing company, we have expanded our team to approximately 100 talented individuals across the UK, Germany, Spain, and beyond. Backed by notable investors such as Index Ventures, Bessemer Venture Partners, Zinal Grow, and Tony Fadell, we have successfully raised $50 million to fuel our growth.Our Engineering CultureAt Apron, engineers play a pivotal role in our operations. Here's what you can expect:Customer-Centric Development: We utilize cutting-edge technology to create products that genuinely enhance our customers' lives.Ownership of Projects: From planning to execution, we take full responsibility for our work.Complex Financial Challenges: We embrace the intricacies of finance, navigating complex business logic and ensuring every detail is accounted for. Precision and attention to detail are paramount in creating a reliable product.Pride in Our Code: We prioritize building fast, secure, and scalable code that can grow with us.Integration of AI Tools: We leverage the best available technologies to ensure our product is genuinely beneficial.Your ResponsibilitiesWe are looking to expand our Card team, which has just launched. As a Senior Software Engineer, you will:Collaborate Across Teams: Work closely with Frontend Engineers, Product Managers, and Designers to develop innovative features.Design Robust Systems: Develop core financial integrations to ensure the security of customer funds and expedite transactions.Drive Innovation: Share your expertise with the team to foster innovation and proactively suggest improvements.

Role overview airapps is hiring a Backend Engineer for its London Metropolitan Area team. This role focuses on designing and building scalable server-side applications that support the company’s products and services. What you will do Work closely with colleagues across different functions to develop backend systems Contribute to the architecture and implementation of server-side features Help ensure backend solutions can scale and perform reliably Location This position is based in the London Metropolitan Area.