Top Software Engineer Jobs in London

The Senior Software Engineer will develop and maintain Lua business logic for ad serving, ensuring performance and reliability while collaborating with product teams on feature delivery.

Build full-stack product software for LabOS, orchestrating automated biology experiments across scheduling, execution, data capture, and results processing. Develop APIs and interfaces for scientists and AI agents, create AI agents and troubleshooting tools, integrate laboratory hardware through programmatic APIs, and design scheduling systems for complex instrument workflows. Own substantial product areas while working independently in an ambiguous, fast-moving environment.

Develop performant, reliable, and well-tested software for a high-performance financial exchange. Work across backend, frontend, cloud, data, and testing systems, including distributed core Java, Kafka, MySQL, JavaScript, Vue.js, Kubernetes, and Python. Collaborate through pair programming, team rotations, continuous integration, and continuous delivery while contributing to greenfield projects, performance-critical components, blockchain integrations, and developer-experience improvements.

Build and maintain scalable Python libraries, tools, and infrastructure enabling machine learning teams to train, evaluate, and deploy models at scale. Develop abstractions for distributed training, data loading, inference, checkpointing, and evaluation; support large GPU clusters and cloud environments; optimize multimodal data pipelines; and improve reliability through architecture, testing, observability, documentation, and maintainability.

Build and own critical web and mobile product surfaces for a trading platform. Develop full-stack features using Scala, Play Framework, React, TypeScript, and AG-Grid; lead migration from Codename One to React Native; improve quality, testing, observability, and performance; mentor engineers; support hiring and onboarding; and collaborate with desktop teams on feature parity and architecture.

Lead large-scale technical initiatives and build scalable product functionality and infrastructure using TypeScript, React, and Node.js. Partner with product and design teams to develop privacy features for SaaS customers, make architectural tradeoffs, mentor engineers, support hiring, and establish engineering excellence across a growing organization.

Designs and maintains scalable RESTful APIs and responsive React interfaces for enterprise financial applications. Works with SQL Server, MongoDB, external APIs, CI/CD pipelines, infrastructure-as-code, and cloud platforms. Responsibilities include secure coding, performance optimization, testing, code reviews, deployment automation, and collaboration with Product and engineering teams. The role may also use AI development tools and integrate AI services.

Join a new London engineering hub to design, implement, and maintain backend services. Own complex backend features end-to-end, drive technical design, ensure high test coverage and scalability, mentor mid-level engineers, and collaborate in a cross-functional agile product team to deliver international-grade products.

Develop and improve backend pricing, discounting, subscription, payment, and financial reporting systems for a large-scale electric vehicle charging platform. Monitor and debug applications and infrastructure, maintain asynchronous processing systems, support payment issue resolution, and collaborate with cross-functional teams to deliver robust, scalable software.

Build and maintain scalable backend systems using Java, Node.js, Spring, AWS, microservices, and REST APIs. Lead architecture and technical design, promote secure and reliable engineering practices, drive automated testing and CI/CD, mentor engineers, collaborate with clients and cross-functional teams, and evaluate AI and emerging technologies to improve software delivery.

Develop and deliver scalable cloud-first software solutions within agile squads. Responsibilities include writing and reviewing maintainable C# and .NET code, designing solutions and databases, creating unit tests, supporting CI/CD, contributing to architecture, championing security standards, mentoring engineers, maintaining documentation, and adopting AI-assisted development tools. The role collaborates with stakeholders and distributed teams across multiple countries while transforming on-premises and cloud systems.

Design and build backend systems for AI agent orchestration, tool execution, workflow management, memory, and state handling. Develop scalable APIs and reliable infrastructure for distributed AI workflows, improve platform reliability and observability, and partner with product, research, and engineering teams to deliver agent capabilities. Own technical initiatives from architecture through production, maintain software quality through testing and continuous delivery, and mentor engineers on backend and distributed-systems practices.

Design and scale backend systems for AI agent orchestration, distributed workflows, experiment management, platform APIs, and developer tooling. Build reliable cloud-native infrastructure, improve observability and performance, partner across engineering and research teams, maintain software quality through testing and continuous delivery, and mentor engineers on distributed systems and backend best practices.

Build and ship reliable, scalable software features for Ledgy’s equity management and financial reporting platform. The role involves contributing across the stack, collaborating with engineers, product managers, and designers, owning well-scoped projects, participating in code reviews and architecture discussions, and translating complex equity workflows into maintainable user experiences. Engineers will work with data models, automation, reporting, tax workflows, integrations, and scalability while growing toward senior-level ownership.

Build and optimize performance-critical backend systems processing millions of real-time records. Design and improve Pigment’s formula and query engine, develop services primarily in C# and .NET Core, contribute to React frontend features, and address scalability, performance, reliability, and architecture challenges. Collaborate with product managers and engineers across the application lifecycle while delivering user-focused solutions and maintaining the production platform.

Designs and implements behavior planning algorithms for autonomous vehicles operating in structured, low-speed airport environments. Responsibilities include developing C++ and Python software, modeling multi-agent interactions, implementing decision-making and path-planning methods, testing in simulation and real-world scenarios, optimizing system performance, and collaborating with autonomy and engineering teams. The role requires expertise in behavior planning, probabilistic models, real-time navigation, debugging, profiling, and scalable software architecture.

Lead the design, development, scalability, and operation of Ebury’s high-volume, multi-currency transactional platform. Own services from architecture through production, build resilient payment and funds-processing systems, collaborate with Product and Operations, mentor engineers, and ensure strong testing, observability, monitoring, and reliability across distributed global teams.

Design and build scalable backend systems, robust APIs, data models, and integrations using Python, GraphQL, PostgreSQL, NoSQL databases, and AWS. Collaborate within cross-functional teams, contribute to frontend applications when needed, own features through delivery, and promote maintainable engineering practices. Mentor teammates and use AI tools to improve development. Frontend experience with React, TypeScript, and Next.js, plus event-driven architecture experience, is beneficial.

Build internal full-stack products across backend, frontend, and infrastructure. Work directly with users to identify needs, create reusable platforms and abstractions, make product and prioritization decisions, and independently ship solutions. Continuously iterate based on feedback while empowering less-technical users. The role requires strong systems thinking, comfort with ambiguity, and proficiency in Python, TypeScript, and React.

The Senior Software Engineer will lead the architecture and development of the Zeta Marketing Platform's Addressability part, focusing on real-time data processing, mentoring developers, and collaborating across teams to build scalable solutions.

Software Engineers at Citadel develop, maintain, and support high-performance trading platforms, focusing on custom software solutions and system stability.

Lead the design, development, and optimization of scalable backend services in Python and Rust. Architect distributed systems, improve reliability through monitoring and alerting, enforce testing and CI/CD best practices, and contribute to backend architecture decisions. Collaborate with product and engineering teams on complex projects, mentor engineers, and ensure the performance and stability of critical platform services.

Lead architecture and technical strategy for Ripple Treasury’s liquidity platform. Build scalable cloud-native systems, real-time cash and liquidity data pipelines, digital asset capabilities, and AI-powered cash-flow prediction features. Mentor engineers, establish engineering standards, improve reliability and observability, manage technical debt, lead design reviews, and own critical systems from development through production support. The role requires deep C#/.NET expertise, database knowledge, large-scale enterprise application experience, and proficiency with modern cloud, frontend, and API technologies.

Design and implement browser-based trading tools with polished, sophisticated UIs. Build reusable UI libraries and abstractions, collaborate across the stack, and work closely with traders to capture user needs. Emphasizes typed functional programming and high UX standards.

Lead development and integration of production-grade, deterministic control software for humanoid robots. Design real-time control architectures, implement high-performance control loops, industrialize algorithms, ensure safety and reliability, run automated testing (simulation and hardware-in-the-loop), manage releases, profile and optimize performance, and mentor engineers.