Top Software Engineer Jobs in London

Intern will be paired with full-time engineers to build production-quality software, learn OCaml (and sometimes Python), and work on diverse projects from trading systems to language design under close mentorship.

Freelance software developer responsible for designing, developing, testing, and maintaining high-performance applications. Collaborate with cross-functional teams to deliver innovative, client-focused solutions on a remote, on-demand platform.

Join ROOST's Coop project to design, implement, test, document, and release trust-and-safety features. Work across backend APIs, GraphQL, databases, and UI to improve reviewer workflows, detection integrations, and reporting. Lead code quality, security practices, community contribution reviews, and stakeholder coordination while engaging with users and the open source community.

Join the ROOST Osprey team to design, implement, test, and maintain a high-performance, real-time safety rules engine. Work includes building data/event pipelines, scaling and containerizing services, integrating with Kafka and gRPC, reviewing community contributions, maintaining code quality and security, and engaging with users and open source contributors to prioritize and deliver features.

Design, build, and maintain scalable microservices and integrations with local partners, payment rails, and government institutions across MEA. Support on-call rotations, incident response, and operational teams; share regional learnings globally to scale Wise's cross-border payments products.

Develop and maintain frontend software for a video management platform using TypeScript and modern frameworks. Implement state management and API integrations (REST, websockets), write tested maintainable code, apply CI/CD and Git practices, debug and analyze issues, and collaborate with cross-functional teams to build resilient, scalable systems.

Design, build and maintain production-grade Python services and scalable APIs supporting risk analytics. Collaborate with Risk Managers and Quants to productionise models, ensure performance, reliability, observability, and improve engineering standards using cloud-native practices and AI-assisted tools.

Build production-grade web and hybrid applications to replace thick-client workflows. Migrate internal utilities, integrate with existing backends, establish CI/CD and test automation, rapidly prototype bespoke tools for high-profile clients, and set web engineering standards across the organization.

Design and implement backend systems for a Performance Medicine EMR. Build Ruby services to capture, move, and protect athlete medical data. Address reliability and scaling for a global SaaS platform and collaborate with product, design, and medical staff to deliver production-ready features.

Lead backend-heavy (80%) engineering to build and improve account integrity and fraud-prevention systems. Design scalable, distributed detection services, operate CI/CD pipelines, optimize relational and non-relational schemas, and deliver frontend features (20%). Own product outcomes, apply TDD, collaborate with Product, Data Science, and Investigations teams.

Own and deliver end-to-end solutions across services, APIs, UI surfaces, and event flows. Design reliable production systems, handle monitoring and incidents, debug distributed systems, collaborate with product and cross-functional teams, and improve quality through tests, observability, and simpler designs.

Design and build distributed backend services for the cloud monetization platform, focusing on correctness, consistency, scalable microservices, distributed transactions, and reliable asynchronous workflows. Influence system architecture, own service implementations, and collaborate across teams to support billing, reservations, payments, and revenue flows.

Build and maintain Paloma's cloud-native full‑stack EPR and AI‑powered patient pathway. Write clean C#/TypeScript code, develop React single‑page interfaces, integrate REST APIs, deploy containerised apps on AWS/GCP, design event‑driven systems, manage cloud SQL databases, automate user journeys, participate in code reviews, and explore AI/agent applications for process automation and assistance.

Lead development of the Live View feature for iOS, build mobile apps that integrate with devices, collaborate cross-functionally, contribute to architecture and design, and follow full SDLC practices including code reviews, source control, testing, and operations.

Develop data extraction and manipulation pipelines, use AI models and NLP (e.g., ChatGPT APIs) to analyze and match available luxury items to customer requests and sales orders, and collaborate to improve matching accuracy and processing efficiency.

Design, build and operate production Scala services within multidisciplinary agile teams to meet GDS standards. Write secure, well-tested code, participate in CI/CD, perform code reviews, and resolve production incidents. Coach junior engineers, contribute to architecture, and collaborate with product, design and user research to deliver user-centred digital services.

Design, build and operate production Scala services within multidisciplinary agile teams to meet GDS standards. Write secure, well-tested code, support production incidents, conduct code reviews, coach junior engineers, and collaborate with product and design.

Develop, test, deploy and maintain secure, scalable backend services and APIs in an Agile environment. Follow secure SDLC and DevOps practices; senior engineers provide architecture direction, lead technical initiatives, mentor engineers, and support high-volume production systems.

Build and own backend platform systems around AI models: design APIs, data models and schemas, implement integrations and data pipelines, create internal libraries/tooling, and drive features end-to-end from design to production while collaborating with engineers and AI specialists.

Build and own full-stack platform systems around AI models: design APIs, database schemas, frontend components, shared libraries, connectors, and data pipelines. Collaborate with design and AI teams, drive features end-to-end from design to production, and shape technical direction and engineering practices.

Build high-quality user-facing experiences primarily in TypeScript and React; influence frontend architecture and product design; own tasks end-to-end; collaborate with designers and AI experts; build component libraries and internal tooling; debug backend issues encountered in development; set technical direction and establish engineering conventions.

Build and maintain scalable Python backend microservices: productionize data science prototypes, fix production issues, improve monitoring, and ensure tested, well-documented code following engineering best practices.

As an ML Engineer at Luma AI, you will design high-performance model serving pipelines, manage GPU resources, and optimize CI/CD for large-scale AI systems.

The ML Engineer will integrate model architectures, optimize deployment workflows, maintain CI/CD pipelines, and ensure reliability of inference services across large-scale systems.

This role requires shaping technical direction, leveraging AI tools for production systems, and making crucial decisions to align product intent with engineering realities.