276 to 300 of 308 API Design Jobs in London

Java / Scala Developer

Hiring Organisation
Quant Capital
Location
London, UK
Employment Type
Full-time
passionate about. The Java Scala developer will be involved in: Web application greenfield developmentWeb analytics & business intelligenceMachine learning, risk modelling, fraud detection. API design and provisionIntegration patterns & messagingHybrid cloud infrastructureJavaScript application developmentWeb application performanceScalabilityExceptional knowledge of low-high level systems coupled with true programming ability. Java Scala Developers ...

Product Manager - Customer Service Platform

Location
Greater London, England, United Kingdom
empathetic support at scale. You’ll help improve the advisor experience through intelligent tooling, define how customers reach support across channels, and strengthen the API layer underpinning our service ecosystem. Your work will bring platform thinking together with real human impact, helping our advisors do their best work … support across chat, email, social messaging, and emerging channels, helping the right contact reach the right advisor at the right time. Strengthen the foundational API layer connecting our support systems, with a focus on reliability, extensibility, and developer experience as the platform scales. Take initiatives from discovery through launch ...

Software Engineer - Cloud Compute Platform

Location
Greater London, England, United Kingdom
global scale. Working in Software means joining a team fueled by curiosity and collaboration. You’ll work with diverse technologies, partners, and industries to design, develop, and deliver solutions that power digital transformation. With a culture that values innovation, growth, and continuous learning, IBM Software places … workloads across Kubernetes clusters and cloud providers, providing common capabilities for scheduling, lifecycle management, security, and operations. You’ll work with experienced engineers to design, implement, test, and operate reliable systems. Areas you may contribute to include: Workload orchestration across Kubernetes clusters Platform APIs and Kubernetes operators Cloud platform ...

Senior Java Developer

Location
Greater London, England, United Kingdom
party integrations. You will work closely with Product Owners, Frontend Developers, DevOps, and QA to ensure smooth, efficient, and secure platform operations. Key Responsibilities: Design and implement backend systems capable of handling thousands of concurrent player connections across multiple services. Develop scalable, modular microservices to support game logic, session … management, and operational services. API Development. Ensure low-latency data processing to support game engines. Collaborate with the product team to build new features, improve system performance, and support business requirements. Work with relational databases such as PostgreSQL and Oracle to ensure reliable and efficient data operations. Manage service ...

Senior Full Stack Developer (C#/React/TypeScript) - REMOTE working

Location
Greater London, England, United Kingdom
/TypeScript Minimum 6 years of solid C# in a commercial environment Produces initial results rapidly and iterate based upon feedback. Knowledge of microservice design principles - preferably with commercial experience. Experience with modern git workflows. Effective communicator and excellent communication skills. Makes pragmatic implementation decisions and can fail fast … rest. Microservices architecture. Docker, Kubernetes in Azure, Vercel. Jenkins/BitBucket Pipelines for CI/CD. RabbitMQ/MassTransit. Microfrontends. Test Driven Development. RESTful API design. GraphQL APIs. Integrations with third-party APIs and SaaS platforms. Benefits Competitive salary and benefits package REMOTE working Holiday allowance 50% staff discount ...

Blockchain / DLT Developer

Hiring Organisation
Delta Capita
Location
London, UK
Employment Type
Full-time
architects, product managers, and client stakeholders, you will bring deep technical expertise and a proactive approach to solving complex on-chain challenges. RequirementsResponsibilities include: Design, develop, and deploy smart contracts and decentralised applications across Ethereum, Hedera, Algorand, and MACH Chain (our proprietary blockchain).Design and implement blockchain-based solutions … equivalent SDKs for Hedera and Algorand. Proficiency in one or more backend languages (e.g. Node.js, Python, Go, Java) and RESTful/event-driven API design. Familiarity with blockchain development toolchains including Hardhat, Truffle, Foundry, or equivalent. Experience with version control (Git) and collaborative development workflows. Strong analytical and problem ...

Engineering London, UK or Ljubljana, Slovenia SDK Engineer

Location
Greater London, England, United Kingdom
binary size, startup cost, thread safety, and backward compatibility are the job, not afterthoughts. You will own what you build end to end, from API design through release and live integration support. Based in-office (hybrid model) in London or Ljubljana, Slovenia. You Will Build and maintain … mobile SDK on Android (Kotlin) or iOS (Swift) Own the public API surface: minimal, stable across versions, and hard to misuse Keep the SDK lightweight and resilient, with no crashes in host apps and graceful degradation when the backend is unreachable Own releases, versioning, and distribution (Maven Central, SwiftPM ...

React Native Engineer

Location
Greater London, England, United Kingdom
with customer requirements and business objectives. Daily Tasks To contribute to Agile Scrum, and ensure deadlines and production quality. To spearhead creative solutions for API and backend related challenges. To manage platform infrastructure for scalability, high availability, and security. To ensure product scalability, high availability, and top-notch code … alerting to maintain high availability. To build, operate, and secure the APIs, backend, and even cloud infrastructure. To incorporate security best practices into the API design and implementation. To evaluate product code against specifications and gathering requirements. To address problems and document all reported issues and actions taken. ...

Full-Stack SDE II: React + Kotlin Backend

Location
Greater London, England, United Kingdom
Engineer II, Full-Stack, to build React-based user interfaces and backend capabilities across Expedia Group brands and B2B experiences. You will contribute to API design decisions, own features from requirements through delivery, and collaborate with product management and cross-functional teams. You will create reusable components ...

Principal Android Engineer - Search & AI-Driven Discovery

Location
Greater London, England, United Kingdom
architectural direction, mentor engineers, and drive AI-enabled capabilities across the mobile platform. The role requires deep Kotlin expertise, Jetpack Compose mastery, and strong API design, with a focus on scalable, high-performance apps that delight travelers and partners alike. #J-18808-Ljbffr ...

Senior Mobile SDK Engineer — Stable APIs, Live Support

Location
Greater London, England, United Kingdom
product, so binary size, startup cost, thread safety, and backward compatibility are the job. You will own what you build end to end, from API design through release and live integration support. Based in-office (hybrid) in London or Ljubljana, Slovenia, you will work on Android (Kotlin ...

Senior Engineer

Location
Greater London, England, United Kingdom
data platform. Define and drive the architecture and strategy to support the future needs of Operations and the business. Provide technical leadership through architecture, design, code reviews, and pull request reviews, championing high standards of code quality and engineering excellence. Mentor engineers and drive continuous improvement in platform capabilities … building and supporting reactive, event-sourced systems. Hands-on experience with Apache Spark and Apache Flink. Strong understanding of Apache HTTP, Envoy, and REST API design. Experience working with Protobuf, Avro, and Parquet data formats. Knowledge of Iceberg, Databricks, and Hadoop ecosystems. Skills that will help Follows TDD, ATDD ...

Senior AI Product Engineer

Location
Greater London, England, United Kingdom
Engineer on the AI team, you\'ll own significant parts of the Agentic stack that power Elliptic\'s copilot. You\'ll lead the design of agentic workflows, drive technical decisions on how we build and operate LLM-based features, and help raise the engineering standard across the team. … take complex problems from ambiguity to shipped product, and you\'ll mentor more junior engineers as the team grows. What you will do: Design and build agentic workflows and AI-powered features that power Elliptic\'s copilot, using LLM frameworks such as LangChain or LangGraph. Lead the design ...

ML Research Engineer: From Research to Production

Location
Greater London, England, United Kingdom
London to advance machine learning platforms and research workflows. You’ll bridge research and engineering, building scalable training and inference infrastructure, and contributing to API design and system improvements. The role emphasizes solid mathematical foundations, experimentation with neural networks and ensembles, and staying current with the ML literature. ...

Global Marketplaces Product Lead – Payments & Wallets

Location
Greater London, England, United Kingdom
Marketplaces product team builds financial infrastructure for marketplace platforms to move money across currencies and countries. The role focuses on direct marketplace engagement, API design, and enabling global expansion with robust fund flow primitives. Ideal candidates bring 5+ years in product management in payments/fintech, strong ...

Lead Solutions Engineer — Apps & Gaming (Advertising Tech)

Location
Greater London, England, United Kingdom
turn business needs into robust technical outcomes. The role requires a hands-on leader with a track record in software delivery, ML infrastructure, and API design, capable of guiding cross-functional groups and communicating complex concepts clearly across audiences. #J-18808-Ljbffr ...

Software Engineer - Core IP Security

Hiring Organisation
G Research
Location
London, UK
Employment Type
Full-time
detection and scanning tools. As a Software Engineer, you will take ownership of designing, developing and operating these systems across service backends, cryptographic libraries, API integrations and hardened infrastructure. The software you build must meet the highest standards of correctness, auditability and availability. You will work on both … following skills and experience: Essential: Strong experience delivering production-quality software, ideally using C#/.NETStrong understanding of software architecture, concurrency, distributed systems and API designExperience building or operating security-sensitive systems where correctness and auditability are criticalSound engineering judgement, balancing security, performance, reliability and deliveryClear communication skills ...

Senior Technical Product Manager – Financial Data Distribution

Location
Greater London, England, United Kingdom
data distribution by working across third party platform distributors and directly with client distribution platforms. Product Discovery & Requirements Definition Lead structured product discovery and design sessions with clients, business, technology, operations. Translate business and client needs into clear product requirements, technical specifications, and prioritised backlog items. Own product documentation … distribution architectures, including APIs, event/batch delivery, entitlement models, and access controls. Demonstrated ability to work effectively with senior engineers and architects on design and tradeoff decisions. Experience defining API/FTP/Web distribution requirements. Preferred: Knowledge of the index business preferred. Experience with agentic solution ...

Senior Front Office Developer - HFT

Hiring Organisation
Quant Capital
Location
London, UK
Employment Type
Full-time
regions with a wide range of strategies. As a Senior Software Engineer, you will work closely with a talented team of engineers to collaboratively design and develop robust software solutions essential for facilitating global trading operations. This includes systems such as trading systems, exchange connectivity solutions, monitoring systems … experience in C++ , Rust, Java and PythonDemonstrated expertise in network communication, including multicast and WebSockets. Proficiency in inter-process messaging, micro-service architectures, and API design. Familiarity with Functional Programming and Immutable Design. Experience with trading systems is desirableExcellent oral and written communication skills. Bachelor's degree in Computer ...

Member of Technical Staff - Applications

Location
Greater London, England, United Kingdom
usable interfaces. Feed delivery learnings back into platform patterns and defaults so the next system ships faster. What You\'ll Work With Full-Stack & API Development: React, TypeScript, REST, gRPC, FastAPI, Go services, API design. Auth & Governance: OIDC authentication, RBAC, audit logging. Workflows & Integrations: Event-driven systems, workflow … About You Strong full-stack engineering background with experience shipping production-grade applications end-to-end. Comfortable owning the full delivery surface — UI through API through auth — without needing to hand off between layers. Experience integrating with external systems or customer environments and making those integrations reliable and maintainable. ...

Senior Software Engineer, Quant trading - Python, RUST, C++

Hiring Organisation
Quant Capital
Location
London, UK
Employment Type
Full-time
regions with a wide range of strategies. As a Senior Software Engineer, you will work closely with a talented team of engineers to collaboratively design and develop robust software solutions essential for facilitating global trading operations. This includes systems such as trading systems, exchange connectivity solutions, monitoring systems … experience in C++ , Rust, Java and PythonDemonstrated expertise in network communication, including multicast and WebSockets. Proficiency in inter-process messaging, micro-service architectures, and API design. Familiarity with Functional Programming and Immutable Design. Experience with trading systems is desirableExcellent oral and written communication skills. Bachelor's degree in Computer ...

Senior Software Engineer, Quant trading

Hiring Organisation
Quant Capital
Location
London, UK
Employment Type
Full-time
regions with a wide range of strategies. As a Senior Software Engineer, you will work closely with a talented team of engineers to collaboratively design and develop robust software solutions essential for facilitating global trading operations. This includes systems such as trading systems, exchange connectivity solutions, monitoring systems … experience in C++ , Rust, Java and PythonDemonstrated expertise in network communication, including multicast and WebSockets. Proficiency in inter-process messaging, micro-service architectures, and API design. Familiarity with Functional Programming and Immutable Design. Experience with trading systems is desirableExcellent oral and written communication skills. Bachelor's degree in Computer ...

Senior Software Engineer, Quant trading - Python, Java, C++

Hiring Organisation
Quant Capital
Location
London, UK
Employment Type
Full-time
regions with a wide range of strategies. As a Senior Software Engineer, you will work closely with a talented team of engineers to collaboratively design and develop robust software solutions essential for facilitating global trading operations. This includes systems such as trading systems, exchange connectivity solutions, monitoring systems … Python (5+ years), Java and or C++Demonstrated expertise in network communication, including multicast and WebSockets. Proficiency in inter-process messaging, micro-service architectures, and API design. Familiarity with Functional Programming and Immutable Design. Experience with trading systems is desirable, but not required. Excellent oral and written communication skills. Bachelor ...

Principal Solutions Architect, Technology Sales Lead (AWS)

Hiring Organisation
VML
Location
London, United Kingdom
Salary
£ 70 K
technical win strategy, lead client-facing deep-dives alongside AWS SAs, and remove the objections that decide competitive deals.Reference architectures that become standards: design the architectures that anchor our joint AWS solutions and get reused across pursuits. Contribute to AWS Partner Central and establish the patterns delivery teams build … patternsData & Analytics: Amazon Marketing Cloud (AMC), AWS Clean Rooms, data lakes, analytics pipelinesCustomer Experience: Amazon Personalize, Amazon Connect, serverless architecturesModern Applications: Lambda, Step Functions, API Gateway, container orchestrationIntegration: Event-driven architectures, microservices, API designHow Success LooksTechnical win rate on the strategic pursuits you leadCompetitive deals turned ...