Top Software Engineer Jobs in London

Lead end-to-end design and rapid delivery of 0-to-1 fintech products with the Founders' Lab. Collaborate with executive leadership to define product direction, build MVPs, deploy to live users, iterate quickly, and balance rapid experimentation with sound backend architecture and occasional frontend/API work. Operate as a product-minded senior engineer in high-ambiguity, fast-paced environments.

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.

As a Staff Software Engineer (ML QA), you'll design and maintain testing infrastructure for the ML software stack, focusing on automation, software quality, and mentoring junior engineers in a collaborative environment.

The role involves building a fraud engine for the Receive Risk team, ensuring secure and fast money reception while mitigating risks. Collaboration with various teams is essential for delivering features efficiently.

Lead development of a cloud-native, low-latency payments platform. Deliver end-to-end payment flows, write and review production-quality code, establish secure AI-assisted engineering practices, drive CI/CD and resiliency, coach engineers, evaluate architectures, and promote reusable patterns across teams.

Build and deploy rapid experiments to drive user adoption, engagement, and early self-serve monetisation. Design and run high-velocity A/B tests, analyze user data, collaborate with product, design, analytics and marketing, and use pragmatic engineering and AI tools to validate growth hypotheses quickly.

Design, develop, and maintain scalable server-side components for the Joybuy online shopping experience. Implement modular microservices, APIs (GraphQL/REST), and CI/CD pipelines, contribute to architecture decisions, estimate and break down tasks, document best practices, and work onsite in London.

As a Senior Digital Assets Software Engineer, you will design and build trading systems, improve system reliability, and collaborate with traders to prototype trading strategies. Your role involves direct integration with cryptocurrency exchanges and contributing to the digital asset platform's architecture.

Design, implement, and operate large-scale C++ build systems and developer tooling. Improve build speed, reliability, and reproducibility via caching, incremental builds, remote execution, CI/CD pipelines, observability, and reusable build libraries. Collaborate with engineering teams to reduce friction and roll out standardized workflows, container images, and pipelines while balancing codebase-specific needs.

Build and optimise ultra-low latency Java systems for pricing, risk and trading. Design scalable, resilient architecture, support live trading, troubleshoot production incidents, and mentor junior engineers while collaborating with quants, front office and business ops.

Design, develop, and optimize a low-latency, high-throughput real-time FX options risk system. Provide architecture leadership, mentor engineers, collaborate with front-office trading and risk teams, implement stream processing solutions using Java, Kafka, Storm, and Couchbase, and ensure high availability, performance, and production reliability.

Develop, integrate, debug, and maintain autonomy software for unmanned aircraft using C++ and Python. Integrate software with hardware, radios, sensors, and flight controllers; support SIL/HIL/VIL, lab and live flight testing; operate ground control systems; analyze flight data; troubleshoot field issues; and produce test and deployment documentation.

Design, maintain, and extend abuse detection and prevention systems for GitLab's SaaS platform. Serve as a core maintainer of a Ruby on Rails monolith, build anomaly detection and agentic AI mitigations, automate abuse response, collaborate with peer engineering and security teams, and produce runbooks and operational documentation.

The Senior Software Engineer II will enhance operational excellence by designing automated reliability systems, incident management tooling, and observability infrastructure while mentoring teams and implementing AI-driven solutions.

Build and maintain Samsara's Cloud Governance Platform across AWS and GCP, focusing on cloud IAM guardrails, automated compliance controls, and software supply-chain security. Implement SAST/DAST and secure CI/CD patterns, design scalable, reliable systems, translate regulatory requirements into automated controls, collaborate cross-functionally, and own components end-to-end while mentoring teammates and shaping the roadmap.

Design, build, test and maintain high-throughput Java Spring Boot backend services on AWS. Build Kafka-based event-driven architectures, drive architecture and reliability, resolve performance and scalability issues, participate in on-call rotations, perform code reviews, mentor engineers, and collaborate with cross-functional teams to deliver pricing platform features.

Join an agile team to design and develop secure, scalable software services using modern technologies. Collaborate with customers and improve skills through learning and feedback.

As a Full Stack Software Engineer at Stint, you will develop and maintain systems using our main stack of Python, Go, GraphQL, and Flutter. Collaborate with product and design teams to implement features and improve our AI-driven platform while ensuring clean architecture and fast deployment.

The Software Engineer in Product will design and implement user-facing systems for Boltz Lab, focusing on usability and integration of complex machine-learning and molecular modeling features.

As a Software Engineer in Infrastructure, you will design, implement, and maintain backend systems for Boltz Lab, ensuring reliable and scalable molecular modeling workflows.

Develop and maintain research-oriented software and infrastructure for evaluation and model hosting. Implement features for Inspect, support open-weights model hosting, design custom research infrastructure, collaborate with researchers, and debug evaluation systems. Work spans cloud infrastructure, MLOps tooling, and open-source contributions.

Build and maintain AI-first product features and internal frameworks for working with LLMs, design reusable architectures and toolchains, develop evaluation systems and benchmarks, experiment with LLM techniques, and take experimental ideas into production while writing high-quality maintainable code.

The role involves designing and developing scalable software components for a Generative Physics platform, integrating AI and simulation tools, leading technical discussions, and mentoring other engineers.

Design, build and support cloud-native applications and services using Angular and .NET/.NET Core on Microsoft Azure. Participate across the full SDLC, collaborate with product and engineering teams, perform code reviews, automate testing and CI/CD, investigate production issues, and contribute to solution design and continuous improvement.

The Software Engineer will develop software for autonomous systems, collaborate with users to refine features, and build user interfaces. Responsibilities include coding, testing, and interfacing with robotic systems while fostering a culture of excellence.