26 to 50 of 109 API Design Jobs in London

maintain high standards of engineering quality. How you will make an impact Build and maintain reliable JVM-based services using Kotlin or modern Java. Design and develop well-structured APIs and integrations. Build reusable services, APIs and components that enable other teams to deliver consistently and reduce duplication. Contribute … API design standards, documentation and versioning across services. Deliver complete end-to-end features by connecting backend services and data models with responsive web interfaces. Use appropriate test-first and test-informed practices to create effective automated tests. Experiment with AI-assisted engineering tools where they provide clear ...

work on the back-end team — leading planning, architecture, and code quality. You will work closely with the wider product and engineering team to design, develop, and maintain the back-end services that power our platform. This hybrid role is based out of our London office near Waterloo Station … reports to the Head of Platform. Responsibilities Back-end development & architecture Design, develop, and maintain scalable back-end services and APIs using Python and modern frameworks (FastAPI). Design and build high-performance API endpoints to handle complex hierarchical data queries and multi-dimensional aggregations for grid ...

development of our next-generation platform channels. Partner on the delivery of new products while continuously maintaining and improving existing ones. Architecture & Design: Collaborate with team members and engineering leaders to design new services and components utilizing our internal Request for Comments (RFC) process. End-to-End Ownership … Micro Frontends (MFEs) is a major plus. DevOps & Cloud: Hands-on experience with Docker, Kubernetes, Terraform, and AWS. Foundations: Strong understanding of system architecture, API design, scalable service integration, Linux systems, and Git version control. Core Soft Skills: Strong knowledge of basic algorithms, object-oriented/functional design ...

systems that enable global commerce, while evolving an existing real-time platform to support new markets. You will address backend capacity constraints and help design a shared transaction and ledger layer used across multiple business lines. This is a hands-on senior engineering role requiring both high-quality delivery … strong technical leadership in ambiguous, high-scale environments. You will be expected to: Design scalable systems with correctness and failure modes considered from the outset Clarify and scope requirements before proposing solutions Make pragmatic trade-offs in system design, avoiding over-engineering Operate independently without reliance ...

deliver against them. It is not a programme, delivery or governance position: you make the architectural calls rather than facilitate them. You will: Design large-scale agentic AI architectures: LLM document processing, structured extraction, RAG, invoice-to-contract matching Own low-level design decisions, including API design ...

delivery methodology to ensure timely and high-quality delivery of software applications. Technical Ownership: Take technical ownership of a product or software solution, covering design, estimation, shaping, and user story/requirement creation. Solution Documentation: Document solutions, including architecture, configuration, release, and support handover. Stakeholder Collaboration: Collaborate and liaise … practices and modern architectural patterns, including microservices and message-driven architectures. Non-Functional Requirements: Experience developing applications with non-functional requirements in mind. Application Design: Experience in application/digital services design. Software Engineering Practices: Proficiency in software engineering practices like code reviews, CI/CD pipelines, and SOLID ...

Required Technology 15+ years of progressive software engineering; 5+ years leading AI‐native solutions at enterprise scale. Hands‐on with LLMs and agentic frameworks; design and deploy AI systems that augment SDLC (requirements → coding → testing → ops). Tooling & Platforms (practitioner proficiency) Claude Code (Anthropic) for secure, context‐rich code …/Gemini for research workflows where permitted; govern enterprise knowledge ingestion. Architecture & Integration Distributed systems, microservices, cloud‐native (Azure/AWS/GCP); secure API design (REST/GraphQL). MLOps & AIOps: CI/CD for AI, model lifecycle (eval, versioning, rollout/rollback), guardrails, telemetry, drift monitoring ...

Design, build, and evolve payment services and capabilities that enable seamless customer transactions across M&S digital platforms. Develop resilient backend services, APIs, and integrations that support millions of customer payment journeys every year. Own features end-to-end, taking responsibility for solution design, development, testing, deployment … testing, and maintainability. Proficient in driving operational excellence through observability and modern engineering practices. Highest-signal resume keywords Java Engineering Expertise Backend Service Development API Design and Integration CI/CD Implementation Observability and Monitoring Hard Skills Backend Development API Development System Design Scalable Systems Resilient ...

where correctness, transparency and performance matter. You'll have real ownership, from architecture through deployment, across new and existing products. What You'll Do Design, build and ship features across the full stack (Fastify microservices, React/MUI, shared TypeScript packages in a pnpm monorepo) Design and evolve … backend services for high-volume, distributed screening workloads Build event-driven pipelines (AWS SNS/SQS) with idempotent consumers, DLQs and batch processing Design clean APIs and contribute to architecture across multiple products Integrate external identity, KYC and payments platforms (e.g. Senzing, Auth0, Stripe) Own services ...

Senior .Net Developer, C#/VB.Net, API, SQL, NW London to £85K A Back End Developer is required to join this established financial software house based in North London. They work with some of the leading brands in retail and media, offering financial management systems developed in house … required with expertise in Visual Basic .NET, C#, SQL Server, and SAP Business One integration. The ideal candidate should have strong skills in RESTful API development, database optimization, and Azure DevOps pipeline management. Knowledge of API security, CI/CD automation, and Swagger documentation is recommended. Responsibilities API ...

built to last and built to scale.* **Drive Scalability & Reliability.** Lead the engineering effort to make RoD elastically scalable and enterprise-grade reliable. Design for high availability, graceful degradation, and zero-downtime deployments. Define SLOs, own the SRE practice for the platform, and be accountable when things need fixing. … fully understood at all times. You will set the standard and ensure the team can operate with confidence.* **Establish End-to-End Testing.** Design and champion a robust E2E testing strategy across the platform. From contract testing at service boundaries to full integration and regression suites, you will ensure ...

deliver the roadmap for horizontal platform capabilities serving all private markets asset classes - including core data services, cross-fund analytics, workflow automation, and API infrastructure. Lead initiatives in AI/ML-enabled product features, including document extraction (e.g., fund documents, LP agreements, investment memos), NLP-powered search, and intelligent … reporting cycles. Demonstrated experience owning platform-level or infrastructure product workstreams with high technical complexity. Familiarity with data architecture concepts: data modeling, ETL pipelines, API design, and event-driven systems. Experience with agile development methodologies; strong proficiency with product management tools (Jira, Confluence, Productboard, or similar). Exceptional ...

Ireland providing specialist services to a wide range of blue-chip clients. The role We are seeking technical polyglots who enjoy both technical architectural design, hands-on coding and peer reviews, though also like the idea of the equally important social/client-facing aspect of the role. … development architecture as well as supporting business analysts and product owners in planning and story-mapping for new development. You will act as technical design authority (TDA) for delivery of technical stories and produce technical documentation artefacts to support the delivery process. Main Responsibilities Duties will include: The design ...

services effectively. The role will be working closely alongside the SPM business team and technology vendors to engineer solutions supporting their strategic roadmap. Responsibilities: Design, build, and improve modern application services that support a strategic business platform, focusing on quality, maintainability, and performance. Develop backend services and APIs supporting … strong track record of delivering production systems. Strong experience building backend applications and APIs, ideally in Java. Practical experience across service‐based architecture, API design, integration patterns, and modern web application delivery. Experience contributing to modernisation or platform evolution initiatives is strongly desirable. Strong engineering discipline across testing ...

work: billing, payments, subscriber management, RADIUS‐based network authentication, and integrations with ISP billing systems and mobile money providers. We are replacing legacy, non‐API systems with a modern API platform, and real money is already flowing through the system. This is a small, high‐intensity engineering team … when they hit technical walls. You will not manage people. You will build systems. What you will own Payments domain: SasaPay collections integration (C2B API, STK push, IPN handling), revenue split engine (per‐partner, per‐BNG percentage logic), ChoiceBank treasury operations (withdrawals, internal transfers, OTP flows), and the payment ...

depth in fraud prevention, abuse detection, rate limiting, or bot protection to guide architectural decisions across a complex, multi-layered fraud stack. Distributed systems design: Proven experience designing, building, and operating scalable, highly available distributed systems in a cloud-native environment. Modern tech stack experience: Demonstrable experience with cloud … platforms (preferably AWS), containerisation (Docker, Kubernetes), and API design (gRPC, REST). Database expertise: Hands-on experience with both relational and NoSQL databases. A people-first approach: Deep commitment to the growth and well-being of your team, with proven experience in coaching, mentorship, and performance management. Commercial ...

secure, and cost-efficient platform infrastructure that enables AI engineering teams to ship and operate AI products reliably in production. What you'll do Design, build, and operate cloud-native AI platform infrastructure across AWS (Lambda, API Gateway, DynamoDB, S3, CloudWatch) and Databricks Deploy and operate containerised services … workflows, and RAG components Implement observability across AI workloads using CloudWatch, MLflow, and OpenTelemetry - covering latency, throughput, cost, and system health Apply secure-by-design principles including IAM, encryption, network controls, and audit logging Work closely with AI engineers to translate prototypes and proof-of-concepts into production-ready ...

applications while collaborating with architects, engineers and stakeholders to deliver innovative digital solutions. The Role As a Senior Software Engineer, you'll lead the design and development of modern cloud-native applications, working closely with clients to understand business requirements and translate them into robust technical solutions. … contribute to solution design, mentor other engineers, promote engineering best practices, and help shape scalable, resilient platforms built on Microsoft Azure. What You'll Be Doing Design, develop and deliver modern cloud-native applications. Build scalable, secure and resilient event-driven solutions. Develop production-quality software using .NET ...

applications while collaborating with architects, engineers and stakeholders to deliver innovative digital solutions. The Role As a Senior Software Engineer, you'll lead the design and development of modern cloud-native applications, working closely with clients to understand business requirements and translate them into robust technical solutions. … contribute to solution design, mentor other engineers, promote engineering best practices, and help shape scalable, resilient platforms built on Microsoft Azure. What You'll Be Doing Design, develop and deliver modern cloud-native applications. Build scalable, secure and resilient event-driven solutions. Develop production-quality software using .NET ...

contexts Use customer feedback, analytics, and direct user insights to inform technical decisions, prioritise improvements, and validate that shipped features deliver measurable value Design and implement complex data flows, API integrations, and background processing systems that handle high-volume operations reliably while maintaining system performance and data integrity … Partner with product, design, and customers to shape solutions early, translating business requirements into technical architecture while surfacing risks and opportunities that impact customer outcomes Mentor and coach other engineers, raising the bar for technical excellence through code reviews, pair programming, and architectural guidance Beyond the tech ...

security etc). Working within a project management/agile delivery methodology Experience in technical ownership for a product or software solution, covering design, estimation, shaping and user story/requirement creation Documentation of solutions (e.g. architecture, configuration, release, support-handover Collaborate and liaise with other Version … including microservices and message-driven architectures NFR/Non-Functional requirement understanding and experience developing applications with this in mind Application/Digital Services Design experience Experience in software engineering practices like Code Reviews, CI/CD Pipelines and SOLID/DRY principals Hands-on developing/coding role ...

foundational systems that power our embedded finance platform at global scale. The team owns multi‐tenant infrastructure, drives cross‐domain product capabilities, and helps design technical solutions for enterprise customers. Key areas of ownership include: Embedded Finance Platform: Build and maintain the infrastructure powering customers like Rippling, Navan, Qantas … career development. Set technical direction for scalable, reliable backend systems and partner with senior engineers on architecture and design. Ensure high standards for system design, code quality, testing, and operational excellence. Drive improvements across reliability, observability, security, and developer productivity. Work cross‐functionally with product, design, compliance, sales ...

skilled Sr. Delivery Consultant to join our team at Amazon Web Services (AWS). In this role, you will work closely with customers to design, implement, and manage AWS solutions that meet their technical requirements and business objectives. You will be a key player in driving customer success throughout … here: https://www.gov.uk/government/publications/united-kingdom-security-vetting-clearance-levels Basic Qualifications Experience as a technical specialist in design and architecture. Experience in cloud-based solution (AWS or equivalent), system, network, and operating system. Experience in external or internal customer-facing, complex ...

Slack and React: the agents people talk to and the apps they click through, built in TypeScript. And you don’t stop there. From API and MCP design to infrastructure on Vercel, AWS, Supabase, and BigQuery, plus the agents that work across the stack, you own complete features … software factory. What you’ll bring 5+ years of experience building applications or tooling that automate human workflows Full‐stack experience across the board: API design, databases, async workflows and background jobs on the backend, and clean, user‐friendly UX on the frontend Being AI‐native. An early ...

Slack and React: the agents people talk to and the apps they click through, built in TypeScript. And you don't stop there. From API and MCP design to infrastructure on Vercel, AWS, Supabase, and BigQuery, plus the agents that work across the stack, you own complete features … software factory. What you'll bring 5+ years of experience building applications or tooling that automate human workflows Full-stack experience across the board: API design, databases, async workflows and background jobs on the backend, and clean, user-friendly UX on the frontend. Being AI-native. An early ...