Top Software Engineer Jobs in London

Senior SDET responsible for designing scalable test strategies, building automation frameworks, managing test environments and data, and executing UI and API tests. Collaborate with engineers and cross-functional teams to ensure quality-first delivery across cloud-native, CI/CD-driven projects in financial services.

Lead strategy, architecture and implementation of test automation frameworks for web and mobile. Design and maintain UI, API and service tests, integrate tools into CI/CD, manage cloud testing, run performance and accessibility testing, and mentor engineers to drive quality engineering across projects.

Design and build reliable, scalable systems for business onboarding and verification across Europe and the UK. Automate information collection and decisioning, create adaptable onboarding journeys, implement controls to mitigate financial crime risk, and own projects end-to-end while collaborating with Product, Compliance, Operations and other engineering teams.

Design, build, and operate scalable, high-performance backend services and APIs. Lead architecture, code reviews, and cross-team integrations. Integrate AI/ML responsibly, diagnose and resolve production issues, and participate in on-call rotations to maintain operational excellence.

Design, build, and maintain low-latency, high-throughput distributed backend microservices for pricing. Implement caching, design APIs and data models, participate in architecture and code reviews, operate event-driven systems (Kafka/Kinesis), and integrate AI/ML-enabled solutions safely.

Develop, test, monitor, and debug production software within a team; apply software design principles, data structures, APIs, and database design; collaborate with stakeholders and continuously improve systems and technical skills.

Senior product engineer working on scaling and building Wealth & Investments features: architect high-availability Yield Engine, build brokerage and trading infrastructure, and deliver secure, high-concurrency distributed systems. Collaborate with PMs, designers, and analysts to define product and technical strategy, break down complex projects, and deliver well-tested, performant web services in production.

Lead development of Java-based services and front-end desktop apps to support pricing, quoting and market workflows for equities derivatives. Drive automation, integrate AI/ML autopricers, build scalable cloud deployments, design secure APIs, promote AI-assisted engineering practices, participate in code reviews, and collaborate across global teams.

Lead technical contributor on the ETF Technology team delivering secure, scalable Java/Oracle applications. Design, develop, test, and support production systems; partner with product, portfolio management, and platform teams; drive operational stability, automation, and adoption of enterprise AI-assisted engineering practices.

Design, architect, and develop scalable Go-based microservices and REST APIs for threat detection, case management, and incident response. Lead system design, own technical initiatives, mentor engineers, integrate AI/LLM capabilities, operate cloud-native services on Docker/Kubernetes and cloud platforms, participate in on-call rotation, and drive reliability and architectural improvements.

Build and scale cloud-native backend services for a global detection-engine platform. Design high-performance, resilient distributed systems, collaborate across teams, mentor engineers, and drive testing, CI, and AI-enhanced detection workflows at internet scale.

Build and maintain ultra-high-scale data platforms and pipelines (petabyte scale). Write fault-tolerant Java/Spark code, design low-latency query capabilities, improve performance and stability, participate in technical reviews, and enable customers/internal teams to query and extract analytics from event data.

Design, implement, and operate discoverability and search features for the AISOAR marketplace. Lead end-to-end technical implementations, ensure high availability and security, troubleshoot platform issues, collaborate with customers and security partners, use observability tools, drive platform improvements, and participate in monthly on-call rotation.

Lead and implement core infrastructure platform initiatives (multi-account/region Kubernetes clusters, MLOps, standardized deployments, authentication). Collaborate with product engineering stakeholders to scope requests, remove operational toil via automation, drive platform adoption, and mentor engineers to improve developer productivity across the organization.

Lead backend engineering to build secure, scalable banking services and shape engineering culture. Drive operational excellence, hiring standards, career development, communities of practice, reusable frameworks, and cross-team collaboration while supporting production systems and incident management.

Lead front-end technical direction and deliver low-latency, real-time trading UIs using React and TypeScript. Define architecture, performance benchmarks, CI/CD/testing strategies, component libraries, and observability practices. Partner with product, design, backend, and SRE teams, ensure secure compliant development, mentor engineers, and adopt enterprise AI-assisted engineering tools to improve code quality and delivery.

Design and build multi-tenant, high-scale payments infrastructure and cross-domain product features. Architect integrations for enterprise customers, ensure production excellence, performance and scalability, and lead multi-team initiatives while collaborating with Product, Design, Compliance, and Sales.

The Staff Software Engineer will lead cross-functional teams to deliver impactful features for the Flights platform, enhancing customer experiences while managing complex technical initiatives.

Design, build, and operate scalable backend systems (80%) and frontend components (20%) to prevent scams and financial crime. Own end-to-end projects, improve detection controls, work with databases, CI/CD pipelines, and collaborate with Product, Data Science, and Investigations to deliver measurable customer protection.

Develop full-stack and backend systems with hands-on Python coding across the full software lifecycle. Contribute to design, integrations, testing, process optimization, and deliver high-quality customer features in an agile team.

Lead design and development of secure, scalable, AI-enabled cloud web applications and APIs for healthcare and R&D use cases. Build full-stack features with Python/Java/C++, modern frontends, AWS services, CI/CD, testing, and integrations while ensuring regulatory compliance (HIPAA/GDPR/GxP) and mentoring engineering teams.

Summer internship contributing to front-office trading analytics: build Python microservices and APIs, develop real-time trading tools and visualizations (Streamlit), work with cloud-native AWS services, Kubernetes, Kafka and Snowflake, support CI/CD and DevOps, and help integrate ML-driven analytics into trading workflows.

As a Software Engineer I at Axon, you'll engage in high-impact projects, develop AI-assisted software, collaborate on code reviews, ensure high code quality, and learn from experienced engineers.

Work on forensic intelligence features for Evidence.com, building forensic playback, investigation tooling, media processing pipelines, and format analysis. Collaborate with product managers and global engineering teams, contribute to code quality and test automation, participate in operational ownership and on-call support, and learn across the stack with mentorship.

Lead a squad to design, develop, and operate the firmwide data catalogue (Fusion), driving secure, scalable solutions, AI-assisted engineering practices, automation, governance, and stakeholder collaboration to enable global data access and platform stability.