Senior Software Engineer I

Thought Machine's mission is bold – to properly and permanently rid the world's banks of legacy technology. To achieve this, we have developed the foundations of modern banking through core and payments technology which run natively in the cloud. What we are attempting is hard and means we need great people working together to build great technology. We have grown rapidly in the past few years – growing our team to more than 550 individuals across offices in London, New York, Singapore, Sydney and our newly established Engineering Hub in Lisbon. We have raised more than £500m in funding and our investors include Molten Ventures, Eurazeo, Intesa Sanpaolo, Temasek, Nyca Partners, JPMorgan Chase Strategic Investments, Standard Chartered Ventures, and more. We have created a culture that enables our team to produce the best work in the industry while ensuring we have fun along the way. We're regularly cited as having a fantastic workplace culture and have been recognised by Sifted magazine as having one of the highest Glassdoor ratings for a UK fintech company and the industry's most generous employee share package. Named one of the world's most innovative fintechs by Global Finance Magazine, we were also recognised by the Financial Times as one of Europe's fastest-growing companies for two consecutive years—and a UK Best Employer for 2026. As a Senior Software Engineer II, you operate with a wide sphere of influence. You will own complex, highly ambiguous technical challenges end-to-end, handling unexpected hurdles independently and gracefully. Your role goes beyond individual team delivery; you will drive systemic, organizational change and shape the long-term technical direction of our platforms. You will actively drive our engineering and company principles by aligning with our broader codebase, architecture, objectives, and goals, while acting as a crucial link between senior leadership, external stakeholders, and engineering teams. WHAT YOU’LL DO Technical Leadership * Design & Build: Create solutions to highly complex problems, utilising a deep understanding of the codebase and architecture, and lead the direction for future technical change. * Architecture & Standards: Utilise expertise to enable solutions to meet security, performance, cost, reliability, maintainability, and scalability requirements in a repeatable way and beyond existing capabilities, shaping the overall technical direction. Take part in defining standards and engineering practices for the entire company. Drive adoption of latest technologies, such as AI-tools, to scale developer velocity and code quality, keeping Thought Machine always ahead of the curve. * Technical Direction: Keep a pulse on industry-leading software trends and best practices, introducing new tools and processes that shape Thought Machine's technical roadmap. * Code Quality & Peer Review: Provide technical leadership and guidance to support others, ensuring their work items consider broader impact, long-term outcomes, and strategic direction end-to-end. * Operational Excellence: Investigate complex issues spanning across services in non-local or production environments (including across environments, clusters, and products), and possess a deep understanding to drive improvements to operational and production support processes. * Hiring: Lead technical interviews to actively evaluate the capability of Subject Matter Experts (SMEs) and leadership roles.. Product & Delivery * End-to-End Ownership: Own the solution to work items of undefined scope and high complexity end-to-end, handling unexpected complexity gracefully and independently. Drive delivery requiring effective and timely stakeholder management across larger milestones, which can potentially span multiple units or departments. * Product Vision: Utilise a deep understanding of the product to envision and contribute to future solutions, plans, and approaches. Drive the direction and actively contribute to the product strategy, vision, and long-term roadmap. Collaboration & Mentorship * Strategic Communication: Communicate seamlessly with stakeholders at all levels, managing leadership expectations while preserving the agility and focus of engineering teams. Build consensus, and enable solutions to complex, changing requirements * Team Growth: Inspire and empower others by example and through your guidance, knowledge sharing, and idea creation. Understand the capabilities and expertise of others to enable effective delegation and personal growth. Empower, inspire, and delegate effectively to senior engineers, fostering an environment of technical excellence and continuous growth. WHAT WE’RE LOOKING FOR * Technical Expertise and Leadership: Deep expertise in modern backend languages (ideally Go/Python) and large-scale, cloud-native systems. A proven technical leader who champions industry best practices, mentors peers, and drives the delivery of solutions to highly complex problems. * Problem Solving: A proven ability to solve highly complex problems of undefined scope, utilising your expertise for decision-making that actively influences the strategic direction of the department. * Production Operations: Extensive experience investigating complex issues across multiple environments, clusters, and products, with a demonstrated ability to drive systemic improvements to operational and production support processes. * Egoless Collaboration: A visionary mindset that does not accept the status quo. You are receptive to new ideas, able to see how different approaches can be combined advantageously, and focused on finding solutions that improve company and client outcomes. * Communication: Exceptional communication skills with the capability to provide leadership across a variety of stakeholders, drive organisational change, and set the direction for how engineers operate with technical excellence. Benefits * Highly competitive salary * Pension plan (match up to 5%) * Life insurance - three times annual salary * Competitive maternity (six months fully paid) and paternity leave (four weeks fully paid) * Shared parental leave (matched to our maternity leave for the same point in time) * 25 days holiday and bank holidays * Flexible working hours * Cycle-to-work scheme * Electric car scheme * Season ticket loan * Access to outstanding learning materials and courses * Sports and hobby clubs, subsidised by Thought Machine * All the latest tech you need * Start the day properly with fresh fruit and cereals * Huge range of healthy (and not-so-healthy) snacks, smoothies and drinks * A talented and experienced team as your colleagues * An environment where we encourage learning and progress * Two charity days a year * Weekly food pop-up We actively hire candidates who demonstrate technical excellence in their field and welcome people of all ages and backgrounds, providing everyone with equal access to professional development. You are encouraged to apply even if your experience doesn't accurately match the job description. We also encourage applications from those with different abilities, including candidates with ADHD, autism, dyslexia or dyspraxia. We actively hire candidates who demonstrate technical excellence in their field and welcome people of all ages and backgrounds, providing everyone with equal access to professional development. You are encouraged to apply even if your experience doesn't accurately match the job description. We also encourage applications from those with different abilities, including candidates with ADHD, autism, dyslexia or dyspraxia.

About Us Sophos is a cybersecurity leader defending 600,000 organizations globally with an AI-driven platform and expert-led services. Sophos meets organizations wherever they are in their security maturity and grows with them to defeat cyberattacks. Its solutions combine machine learning, automation, and real-time threat intelligence with frontline human expertise from Sophos X-Ops to deliver advanced, 24/7 threat monitoring, detection, and response.   Sophos offers industry-leading managed detection and response (MDR) alongside a comprehensive portfolio of cybersecurity technologies — including endpoint, network, email, and cloud security, extended detection and response (XDR), identity threat detection and response (ITDR), and next-gen SIEM. Together with expert advisory services, these capabilities help organizations proactively reduce risk and respond faster, with the visibility and scalability needed to stay ahead of evolving threats.   Sophos goes to market with a global partner ecosystem, including Managed Service Providers (MSPs), Managed Security Service Providers (MSSPs), resellers and distributors, marketplace integrations, and cyber risk partners, giving organizations the flexibility to choose trusted relationships when securing their business. Sophos is headquartered in Oxford, U.K. More information is available at www.sophos.com. Role Summary   We are seeking a Senior Software Engineer to join our Managed Services and Emerging Technology Group. The successful candidate will bring strong hands-on experience in Go, ideally alongside experience in TypeScript, to design, build, ship, and support reliable software within a collaborative engineering team. This role is suited to an engineer who can lead complex feature and service delivery end to end, contribute to technical direction and engineering standards, mentor less experienced engineers, and make effective use of modern developer tooling, including AI-assisted tools, while continuing to strengthen our frontend and backend platforms.