Top Software Engineer Jobs in London

Develop high-performance, real-time sports data services using C#/.NET and modern engineering practices. Apply Specification-Driven Development, ATDD/BDD, AI-assisted tooling, AWS/serverless and GitLab CI to build and maintain scalable APIs and frontend features (ideally React). Collaborate in an Agile team and translate cricket domain complexity into software solutions.

Own end-to-end development of automation and AI-driven systems across tenant find, property management, or payments. Responsibilities include understanding complex operational workflows, identifying automation opportunities, designing scalable architectures, collaborating with product managers, making pragmatic AI and agentic system decisions, and delivering reliable solutions from concept through production. The role requires strong product judgment, technical ownership, and the ability to improve business outcomes in a fast-changing environment.

Design, implement and maintain scalable, high-performance backend microservices. Write automated unit and integration tests, manage deployments from testing to production, collaborate with other engineering teams, translate customer requirements into deliverables, and work on client-facing scoping and delivery.

Build and maintain Joybuy backend systems ensuring performance, availability, concurrency, security, and scalability. Identify and mitigate technical risks with monitorability, maintainability, and grey-release/rollback strategies. Research and adopt new technologies, integrate emerging tech into global architectures, and work onsite in London.

Develop and maintain Joybuy backend services for European retail markets, emphasizing high performance, availability, concurrency, security, scalability, and global integration. Mitigate technical risks, implement monitoring and rollback strategies, research and adopt new technologies, and collaborate with product teams across marketing, fulfillment, and supply chain.

Design, build, and maintain Joybuy backend systems focused on performance, availability, concurrency, security, and scalability. Identify and mitigate technical risks, enable monitorability and rollback, research and adopt new technologies, and integrate emerging tech into global architectures.

Generic Software Engineer role at JD.com. Description provides company and team overview but lists no specific responsibilities, tech stack, or required duties. Opportunity to join a collaborative, global engineering team working on supply chain and logistics technology.

Lead architecture and backend development for international core systems, ensuring high availability, concurrency, security, and scalability. Design Java/Spring Boot services, optimize performance, integrate MySQL/Redis/Kafka, manage technical risk, drive productization, mentor engineers, and coordinate with suppliers and product teams. Onsite role in London supporting European operations.

Build and maintain production-grade iOS applications using Swift and SwiftUI, integrating AI through backend APIs. Design reliable AI interaction patterns, optimize performance and memory, support concurrency and background tasks, capture user feedback, and collaborate with backend and machine learning engineers. Maintain App Store quality, monitor production issues, and deliver responsive, stable, and efficient user experiences.

Design and implement cloud-native security controls and guardrails across Azure/AWS/GCP and managed Kubernetes clusters. Improve product security in the SDLC by building secure infrastructure-as-code, admission controls, secrets management, and observability. Perform architecture reviews, security assessments, and support incident detection and response while advising platform and engineering teams on secure AuthN/AuthZ, service mesh, and cluster hardening.

Design, implement, integrate, and validate autonomy and mission behavior for robotic platforms. Deploy software onto embedded Linux hardware, run SIL/HIL tests, support live UAV flight tests, troubleshoot integration issues, and collaborate with cross-functional teams and third-party vendors to deliver modular autonomy solutions for defense customers.

Design, develop, test, and deploy high-performance modern C++ software and libraries. Work with product managers and customers to translate requirements, contribute to CI/CD, build automation, and containerized deployments, and occasionally travel to customer sites and offices to integrate and validate systems.

Develop and optimize low-latency trading systems alongside traders, researchers, and risk analysts. Participate in training, own well-architected code, and apply knowledge of algorithms, concurrency, CPU architecture, operating systems and databases to support real-time market decisioning.

Ten-week software engineering internship building and shipping production code for Optiver's real-time trading systems. Work with mentors and cross-functional teams on performance-sensitive projects, learn trading fundamentals, and may receive a full-time offer based on performance.

Designs and evolves scalable data pipeline, orchestration, and inference infrastructure for autonomous driving data platforms. Responsibilities include developing DAG-based workflow systems, tooling, shared libraries, batch inference capabilities, and high-throughput processing workflows. The role focuses on reliability, performance optimization, resource prioritization, incident response, and collaboration with partner teams to support large-scale data ingestion, processing, evaluation, and machine learning operations.

Design, build, test, and operate scalable backend services, APIs, and microservices. Work on distributed systems, asynchronous workflows, messaging, and event-driven architectures. Troubleshoot production issues, improve reliability and observability, participate in code reviews, CI/CD, and collaborate cross-functionally from design through production.

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.

Lead the technical vision and development of Elasticsearch’s core search infrastructure, including indexing, retrieval, query execution, and relevance. Research search algorithms and data structures, contribute to Lucene, guide technical roadmaps, collaborate across teams, mentor senior engineers, and build high-performance distributed search systems. Serve as a subject-matter expert while driving projects from concept through completion.

Develop and maintain quantitative trading strategies, pricing models, backtesting frameworks, and market simulations for cryptocurrency markets. Collaborate with traders and quantitative researchers to convert ideas into production software, manage strategy deployment and real-time tuning, and analyze performance data to improve returns and generate alpha. The role requires strong software engineering, quantitative finance, market microstructure, and algorithmic trading expertise.

Design, develop, test, and maintain scalable backend applications, services, and APIs using modern engineering practices. Responsibilities include architecture and solution design, unit and integration testing, troubleshooting, code reviews, technical discussions, Agile collaboration, continuous improvement, and mentoring junior engineers. The role emphasizes performance, reliability, scalability, security, maintainability, and translating business requirements into high-quality technical solutions.

Build and improve resilient fintech platforms in Java within a small, collaborative team. Responsibilities include pair programming, refactoring, extensive automated testing, continuous integration, test-driven development, behavior-driven development, domain-driven design, and process automation. The role emphasizes whole-system ownership, clear communication, continuous learning, and consideration of performance factors such as throughput and latency.

Build and improve resilient fintech platforms in Java within a collaborative, pair-programming team. Responsibilities include refactoring code, writing comprehensive automated tests, automating processes, and accounting for performance, throughput, and latency. The role uses trunk-based development, continuous integration, TDD, BDD, and DDD. Candidates need commercial Java experience, professional software development experience, TDD exposure, strong communication skills, and willingness to pair-program full time.

Build and extend high-scale egress-path systems running on Linux kernel and network dataplanes. Work on kernel network stack (eBPF), routing (BGP), and distributed systems to optimize packet flow, reliability, and performance. Collaborate across teams and participate in on-call rotation.

Design, develop, and deploy scalable SaaS applications while implementing DevOps practices, ensuring high performance, and collaborating with the product team to enhance user experience.

Design, develop, and maintain cloud networking foundations for Neo4j Aura. Collaborate across teams to scale global cloud networking, improve platform performance, reliability, and scalability, and operate Kubernetes-based SaaS infrastructure.