Top Software Engineer Jobs in London

Build and maintain backend frameworks and libraries using Java and Spring Boot to enable product teams to build and run scalable financial services. Collaborate with SDLC and Infrastructure teams, design reusable components for functional and non-functional needs, mentor engineers, and drive standardization, compliance, and platform-as-a-product improvements.

Maintain and improve C++ codebases for the Cfx.re creator platforms (FiveM/RedM). Drive release planning, CI/CD, build/test automation, and platform health monitoring. Triage and resolve critical issues, collaborate with cross-functional teams, and optimize system performance and memory usage.

Lead design and implementation of scalable, resilient backend services for KYC/onboarding using Java and Spring. Drive architecture, mentor engineers, improve automation and reliability, collaborate with product, and build internal tools for verification workflows while ensuring security and data protection.

Lead backend development of Aether's core platform: design and build high-performance APIs, implement complex business logic, scale services for 3D modeling, simulation, and proposal workflows, and influence system architecture in an early-stage environment.

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 and deliver production-grade React and TypeScript portals and dashboards backed by Snowflake pipelines. Integrate front-end with backend inference APIs and analytics, ensure high-throughput performance, availability, security, and role-based access. Own front-end DevOps, contribute component libraries and collaborate with ML and backend engineers to surface model insights.

Develop, maintain, and test software for Motorola's systems, with a focus on frontend technologies and state management. Collaborate with teams and implement best practices.

As a Full Stack Software Engineer, you will develop features for the Mirror App, Mobile Apps, and web applications, collaborating with product, QA, and customer support teams, while contributing to a revolutionary fitness technology.

Develop and maintain FlexONE OMS/EMS features in Java/Scala. Design UI components (Swing), implement features and performance improvements, write unit tests, and support CI/CD (Docker, Jenkins) within an agile Kanban team.

Design, build, and deploy production-scale AI systems including multi-agent workflows, RAG pipelines, and fine-tuned LLMs. Deliver full-stack web and backend integrations, develop evaluation frameworks and monitoring, iterate prototypes into production, and shape internal best practices for applied AI.

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.

Design and build distributed systems for large-scale AI training, focusing on performance, stability, monitoring, and debugging of infrastructure.

Design, develop, and maintain Entrust's iOS SDK for document capture. Implement camera capabilities, on-device image processing and ML, integrate RESTful APIs, improve CI/CD and test automation, collaborate with product and design to deliver accessible, high-quality SDK features across devices.

Develop and deliver Java-based microservices across the full lifecycle, write automated tests, participate in agile ceremonies, triage and resolve issues, and improve platform quality, stability, and performance.

Build and operate agentic developer tooling and shared engineering services to improve productivity for 1,200+ engineers. Own production software from design to operation, build an engineering knowledge base (MCP server), run AI enablement workshops, improve developer portal and shared services, and use research and telemetry to drive cross-team adoption and efficiency.

Develop and maintain scalable cloud ecosystems using Golang and Python, enhancing backend microservices and collaborating within a fast-paced team.

Build and scale Wise's Acquiring Platform to receive international payments. Design and implement backend services and RESTful APIs, integrate payment methods (Google Pay, Apple Pay, PIX, UPI), expand platform into ecommerce stores and PSPs, work on distributed systems, collaborate with stakeholders, and deliver shippable milestones.

Build and maintain the Payin Platform that handles how money enters Wise. Design Payin Session and Payment abstractions, ensure reliability and scalability for high-volume transactions, collaborate across teams, write testable code, drive end-to-end ownership, and improve APIs and systems for excellent customer experience.

Join Core Infrastructure to maintain and scale Tier 0 infrastructure hosting hundreds of microservices. Design, implement, test code, participate in on-call rotation and code reviews, and collaborate with platform users to troubleshoot and improve systems. Gain hands-on experience with C++, Python, Linux, cloud, Kubernetes, and Terraform.

Build and operate GenAI production infrastructure for open-weight LLMs and VLMs: real-time GPU serving, high-throughput batch inference, fine-tuning, autoscaling, backend services, observability, and platform surfaces enabling teams to ship GenAI products.

Build and operate production GenAI infrastructure for open-weight LLMs and VLMs: real-time GPU serving, high-throughput batch inference, fine-tuning, autoscaling GPUs, backend services, observability, cost/latency optimization, and platform surfaces (LLM/Agent Gateways, evals, guardrails).

Build, maintain, and scale a multi-venue collateral management platform and related reference data and accounting systems. Design resilient, real-time event-driven distributed systems, integrate trading venue data, contribute to architecture, and own production delivery and support.

Build and own full-stack AI platform systems: backend services, data pipelines, frontends, and cloud infrastructure. Integrate LLM agents with lab data, instruments, and databases; prototype and harden agentic workflows; write well-tested code; mentor teammates and drive engineering best practices in a research-focused environment.

Full-stack mid-level engineer building and operating secure research environments (frontend, backend, infrastructure). Work includes Typescript/Node development, IaC (Terraform), Azure/Kubernetes, data modelling, operational management, and collaborating with cross-functional teams to enable secure researcher access to sensitive health data.

Build full-stack tools for AGI safety research: evaluation IDE, LLM-powered search, comparison views, streaming results, collaborative log editing, pipelines, agents, and telemetry. Collaborate with researchers and product to deliver robust, extensible software.