1 to 25 of 27 Senior Software Engineer Jobs in the City of London

Senior Software Engineer Node.js/AWS/React London (Hybrid, 3 days onsite) Are you the kind of Senior Software Engineer who enjoys taking something fast-and-scrappy and turning it into something scalable, elegant, and genuinely robust? This is a chance … Senior Software Engineer to join a small, but ambitious tech-for-good/IoT startup based in the London City Centre thats building products to make sense of massive data streams. Youll be part of a tight-knit team (around ten people total, five software engineers ...

Senior Software Engineer | Distributed Systems | Sustainable Cloud Native Platform 💸Up to £110,000 per annum plus bonus plus stock 🏠Central London office 🖱️Golang, Rust, C, Kubernetes, Linux, Cloud Native, Distributed systems... Are you a Senior Software Engineer with extensive knowledge of building distributed systems … so... I'm partnered with a very exciting Cloud scale-up who have received record Series A funding and are looking for innovative Senior Software Engineers to join their ambitious team! With a new VP of Engineering who has spent much of their career building out a world ...

Senior Software Engineer Node.js/AWS/React London (Hybrid, 3 days onsite) Are you the kind of Senior Software Engineer who enjoys taking something fast-and-scrappy and turning it into something scalable, elegant, and genuinely robust? This is a chance … Senior Software Engineer to join a small, but ambitious tech-for-good/IoT startup based in the London City Centre thats building product click apply for full job details ...

exciting opportunity has arisen for a Senior Software Engineer to join a well-established biotech company using large-scale genetic data and AI to predict disease risk and advance precision healthcare. As a Senior Software Engineer , you will be contributing to the development … scaling of secure, reliable software in a collaborative, agile environment. This is a contract-based role (12 weeks) offering hybrid/remote working options, a salary range of £500 - £700 per day (Inside IR35) and benefits. You will be responsible for: Building and scaling new software products within ...

Senior Software Engineer Key Technologies: C#, .NET, React, JavaScript, Typescript, AWS, Docker City of London, United Kingdom Perm Role: £80,000 - £120,000 Harrington Starr has partnered with a Global Financial Services Vendor and they are looking for a Senior C#, .NET Software Engineer … work in the UK. This role offers hybrid working, with an office location based in the City of London. This role will suit a Senior Software Engineer, with expert C#, .NET experience having a direct impact from the get-go. ...

Senior Software Engineer (Python - FastAPI) This fast-growing consultancy is pushing the boundaries of AI and data science, helping clients turn complex challenges into scalable, production-ready solutions. They’re now hiring a Senior Software Engineer who can blend deep technical expertise with … above What You’ll Be Doing: Leading the end-to-end design and build of applications that utilise advanced AI and data-led software solutions. Developing scalable data pipelines and backend services that support complex modelling work. Setting standards for clean, efficient engineering across Python(FastAPI), SQL and cloud ...

Senior Software Engineer London – 1 day a week onsite Are you a highly experienced individual contributor looking for a step up into a senior position in a high-performing team within the world of Banking/Payments? Are you passionate about high-throughput, real-time systems … like!) 🌍 Opportunity to collaborate with major global banks 🚀 Fast-paced, product-led environment where your voice matters If you're a motivated Senior Software Engineer ready to tackle complex challenges and deliver meaningful change, hit apply – and shape the future of payments with us. ...

Role: Senior Software Engineer/COBOL Developers/Engineers Work Location: London, Glasgow or Newcastle (Office based) Duration: 6 Months+ Our banking client is currently seeking a Senior Software Engineer/COBOL Developers with hands-on expertise in FIS Systematics to join a dynamic … banking system migrations or upgrades. Familiarity with Agile methodologies. Experience working with global teams. Essential Experience: Client facing, Very Good Communicator Good coding and software development experience Committed to highest quality standards and delivery excellence Natural Leader ...

Role: Senior Software Engineer/COBOL Developers/Engineers Work Location: London, Glasgow or Newcastle (Office based) Duration: 6 Months+ Our banking client is currently seeking a Senior Software Engineer/COBOL Developers with hands-on expertise in FIS Systematics to join a dynamic ...

Senior Software Engineer (Full-stack) - Permanent | On-Site | London Join a rapidly scaling US-backed startup at a pivotal moment. With significant funding secured and strong momentum, they are establishing their UK presence and offering exceptional equity opportunities for early team members. As a Senior Software Engineer, you'll work across our Python and TypeScript stack, contributing wherever the team needs you most. What You'll Be Doing: Develop and maintain FastAPI (Python) and Next.js (TypeScript) applications. Own features end-to-end - from user interface through to infrastructure and internal tooling. Navigate and contribute ...

Senior Software Engineer, Python, Django, ReactJS, JavaScript, PHP, Mainly Remote, Central London Senior Software Engineer (Python, Django, ReactJS) required to work for a fast growing and exciting business based in Central London. However, this role is mainly remote. We need an experienced Python Developer ...

Senior Software Engineer Location: London - Hybrid (Occasional Travel required) Salary: £75,000 - £95,000 An established, global technology business within the hospitality-tech industry is seeking a talented Backend Software Engineer to help build and scale cutting-edge digital solutions. This is a chance … doing? Design, develop, test, and maintain high-performance backend systems supporting real-time hospitality operations. Take ownership of key features throughout the software development lifecycle - from technical design through to deployment and ongoing optimisation. Collaborate with cross-functional teams including product, design, and data science to deliver innovative, customer ...

Senior Software Engineer (Python) 💰 Up to £130,000 + excellent benefits (including work from abroad) 📍 Hybrid - 2 days onsite in Central London (London Bridge) Are you a Senior Python Engineer who loves solving deep technical challenges? Want to help reinvent how future hardware is created … building a revolutionary platform that turns high-level hardware requirements into complete circuit designs. You’ll work on complex problems at the crossroads of software, data and engineering, collaborating with experts across multiple disciplines. What You’ll Do Own and evolve backend systems across data models, algorithms, infrastructure ...

Title: Senior Software Engineer Salary/Package: £80k-£100k + Equity Company Sector: Fintech (SaaS) Tech: TypeScript, Node, React, Next, GraphQL, AWS Location: Central London (London Bridge/Bank) WFH/Hybrid: 2-3 days in office (Bank) I’m hiring a full-stack Software Engineer … impact Are curious about AI, automation, and modern code-assist tools (Cursor, Copilot, etc.) Move fast, test properly, and think like a product engineer Enjoy working in small, high-energy teams Bonus Points For: Experience with Postgres, Prisma, GraphQL, Next.js Exposure to LangChain/LangGraph/AI-driven workflows ...

Senior Software Engineer Location: London (Hybrid/On-site) Salary: £100,000 – £150,000 + equity About the Company We’re working with an early-stage, venture-backed legal technology startup on a mission to transform one of the UK’s most broken consumer experiences: the legal … strong foundation for navigating regulation while moving quickly in a traditionally slow industry. The Role This is an opportunity for a Staff or Senior Product Engineer to join as one of the earliest engineers in the business. You’ll be part of a small, high-calibre team ...

Senior Software Engineer Full Stack - Ruby on Rails, React Up to £120k DOE Fully Remote - must be UK based A fast-growing sports tech company building high-performance, data-driven products for a rapidly expanding global audience is searching for a Senior Full Stack Engineer . This is a pivotal role for an experienced engineer who thrives on shaping architecture, driving technical direction, and still remaining hands-on in the codebase. As a technical leader within a cross-functional Product Team, you’ll influence the long-term engineering strategy, guide architectural decisions ...

Software Engineer London/Hybrid | Perm Role £80,000 - £100,000 Harrington Starr has partnered with a fast-growing fintech that’s transforming how businesses manage foreign exchange and treasury operations. Their technology enables clients to access institutional-grade execution, automate manual workflows, and gain greater transparency across … product offering and deliver cutting-edge solutions that help clients manage risk more effectively. The Role This is an excellent opportunity for an experienced Software Engineer — ideally with a background in financial technology or FX — to join a high-performing engineering team within a scaling fintech. ...

Senior Software Engineer – 3D Graphics/Computer Vision London preferred | Full-time | Visa sponsorship available The mission Work at a stealthy 3D/graphics startup that turns real‐world objects into production‐ready, photoreal assets for film, games and real‐time experiences. Think: high‐end material capture … photogrammetry tools used behind the scenes by top studios, not off‐the‐shelf consumer software. The role You’ll be the go‐to engineer for 3D rendering and asset processing in a Windows desktop app that sits at the heart of the company’s pipeline. Expect deep work ...

Senior C# Engineer City of London (On-site) Permanent | £90,000 – £120,000 We’re partnered with an innovative proprietary trading firm in the City of London that is hiring a Senior C# Software Engineer . You’ll work on greenfield projects, cutting-edge technology ...

Senior C++ Software Developer, Python - Financial/Banking Candidates will have 5+ years C++ experience (ideally more) and excellent knowledge of Python - ideally coming from a Financial/Banking background with knowledge of Equities, Futures & Options and Fixed Income and Exchange Connectivity, FIX Protocol and some Low Latency … work with the Product, Infrastructure and QA teams, to produce high performance, low latency and highly reliable code. Your goal will be to develop software which handle large amount of TPS to drive a highly efficient technology used by several markets around the world. To be successful in this ...

Lead Software Engineer – Java Microservices | London (1 day per week on-site) | £74,000 – £92,000 + Package We’re partnering with a leading UK bank to recruit a Lead Software Engineer with strong Java and microservices expertise. This is a hands-on role building high … performance, scalable software for real-world, high-traffic systems. About the Role You’ll join a permanent feature team, taking end-to-end ownership of services, from design and development to testing, deployment, and optimisation. Your focus will be on building robust microservices that support high-traffic user experiences ...

client is looking for an experienced Senior C++ Software Engineer to help grow and enhance our PTP software platform. The candidate will work on strategic enhancements to the platform as well as on client implementation projects. The PTP Platform is a leading-edge, cloud-based Securities … Processing solution that provides trade lifecycle processing for a wide range of global financial institutions. What you will need: · Extensive commercial software development experience using C++ · SQL experience · Unix/Linux experience · Relevant degree in a numeric discipline, or equivalent work experience · Excellent written and spoken English Added bonus ...

Backend Engineer (Rust/Python – DeFi Trading) London or Remote (Europe) A DeFi-native trading platform is building high-performance, user-focused trading tools and is looking for a backend engineer to help shape the core platform. The team strongly believes DeFi is the future of finance ...

data science problem. They are deploying massive compute clusters and proprietary machine learning models to trade billions of dollars daily. If you're an engineer who cares about nanoseconds, cache locality, and architecting petabyte-scale infrastructure, this is the pinnacle of technical challenge. What You’ll Work On Architect … implement the critical path for trading execution, building order management systems and market connectivity layers where performance is measured in microseconds. Scale Data Pipelines: Engineer elegant, distributed systems capable of ingesting and processing petabytes of market and alternative data, ensuring absolute consistency for research teams. Operationalize Machine Learning: Bridge ...

About Us: We’re a VC-backed stealth-mode company building behavioural AI solutions for the retail industry. Our platform is designed from the ground up — no legacy, no patchwork systems — just a clean slate ...