26 to 47 of 47 API Design Jobs in London

fast to take things to the next level. Youll join as a Senior Backend Engineer , taking ownership of complex Python/Django services that power enterprise decarbonisation. Expect to design elegant APIs, tackle data-heavy challenges, and collaborate closely with sustainability experts and product teams. What makes this special? High-performance engineering team smart, passionate, and collaborative Big mission …/CD, and plenty of greenfield challenges Youll be a great fit if you bring: 7+ years backend experience (Python expertise essential) Strong knowledge of Django (or similar) and API design Experience scaling apps, with an eye for performance and reliability A proactive, problem-solving mindset and love for collaboration Enjoy a collaborative, chic, and modern office environment More ❯

Manchester) Up to £160,000 + benefits/Bonus Join a leading financial technology and trading organisation driving innovation in electronic markets. As an eFX Software Engineer, you'll design and deliver high-performance, low-latency trading solutions that underpin mission-critical systems. This role offers the chance to work on cutting-edge technology where speed, scalability, and resilience … are key. About the Role Lead the design and development of secure, high-performance eFX systems Define and evolve Java patterns and techniques optimised for ultra-low latency (<40s) Architect fault-tolerant, scalable trading systems Influence technical strategy, architecture, and product roadmaps Collaborate with multiple teams to deliver best-in-class E-trading platforms Ensure all solutions meet security … compliance, and performance standards What You'll Bring Strong experience in software engineering, architecture, and database design Expert-level Java development, including low-GC and lock-free patterns Proven background in FX trading systems, pricing, and risk management Deep understanding of CPU architecture, cache optimisation, and Linux performance tuning Expertise in networking and messaging (TCP, UDP, Multicast, FIX) Knowledge More ❯

Strong ability to integrate with REST APIs, manage secure authentication flows, and handle offline scenarios Basic understanding of backend systems (e.g. Node.js, AWS) to debug issues and contribute to API design discussions Proficient in Git, with best practices for branching, tagging, and changelogs Comfortable using tools like Jira, TestRail, and writing technical documentation Experience working in cross-functional More ❯

London (x3 days a week onsite) Salary: Up to £80k DOE Type: Perm Job Description We are looking for a passionate Senior Java Engineer in London to lead the design and development of core product features and services that power an app used by thousands of travellers on a daily basis. As a Senior Java Engineer for an loyalty … and business logic Building out impactful product features Ensure the quality of the features you built, follow-up on usage/issues post release. Work closely with product and design team to deliver new features that align with the needs of the business Provide technical leadership and mentoring to other engineers on the team Contribute and drive frameworks that … team in understanding and adopting new technologies What We're Looking For: Strong programming skills and CS fundamentals combined with 5+ years of experience building products Deep architecture and API design skills to build core services and new product features Strong sense of ownership demonstrated through shipping production-quality code equipped with testing, monitoring and documentation Passion for More ❯

data-heavy workloads while influencing product strategy. Requirements: Strong foundations in algorithms, data structures, and distributed systems Experience building and operating large-scale backend systems Expertise in system and API design, scalability, and performance tuning Proficiency in a modern backend language (Java preferred) Knowledge of cloud-native architectures, containers, and CI/CD Proven leadership in technical strategy More ❯

and data-heavy workloads while influencing product strategy.Requirements: Strong foundations in algorithms, data structures, and distributed systems Experience building and operating large-scale backend systems Expertise in system and API design, scalability, and performance tuning Proficiency in a modern backend language (Java preferred) Knowledge of cloud-native architectures, containers, and CI/CD Proven leadership in technical strategy More ❯

Deep understanding of UK wealth management business processes, including portfolio management, client onboarding, reporting, and regulatory requirements Knowledge of financial markets, investment products, and portfolio construction principles Familiarity with API design and integration patterns in financial services Experience with user research methodologies and customer journey mapping Understanding of modern web technologies and their application in financial services Previous More ❯

the Customer Journey Product Line, you'll play a key role in shaping the systems and services that power how users find and discover information across HubSpot. You will: Design, build, and maintain scalable backend services that support global search and discovery experiences across the HubSpot platform. Collaborate closely with product managers, frontend engineers, and data teams to deliver … optimization, and personalization. Improve system reliability, observability, and performance across services that touch millions of customers daily. Write clean, maintainable, and well-tested code while applying best practices in API design, data modeling, and service architecture. Help guide technical direction and contribute to long-term engineering decisions that shape the evolution of HubSpot's Global Search platform. Participate … that can evolve quickly and safely. Thrives on solving challenges involving search relevance, data flow, indexing, and performance at scale. Communicates clearly and works collaboratively across engineering, product, and design teams. Is excited about building intelligent, adaptive systems that make finding information effortless for users. Why This Role Matters Global Search is central to how millions of HubSpot users More ❯

testing activities. Key Responsibilities: Lead requirements analysis and documentation for complex digital projects. Write clear, detailed user stories for development and test teams. Specify and model data requirements, including API documentation. Facilitate workshops with stakeholders to capture business needs. Collaborate with Agile teams to ensure alignment with delivery goals. Maintain awareness of emerging technologies, including generative AI. Essential Skills … modelling. Demonstrated ability to write user stories for large development teams. Experience working in high-performing Agile or Scrum environments. Desirable Skills: Knowledge of digital transformation programmes. Familiarity with API design and documentation. Awareness of generative AI concepts. Professional certifications (e.g., BCS, IIBA) desirable but not mandatory. Please submit a copy of your CV for more information on More ❯

in shaping the core transactional and accounting infrastructure that underpins Pleo's spend management solution. You will be the deep subject matter expert on accounting, transaction management, and external API capabilities, ensuring our platform is robust, scalable, and compliant. You will own the product direction for the systems responsible for processing and managing payment transaction records, financial reconciliation, and … As a Senior Product Manager, you will: Bring deep subject-matter expertise in accounting, with a strong focus on payment transaction records, reconciliation flows, and financial data management Understand API fundamentals - particularly the requirements for exposing APIs externally - and ensure the platform enables seamless integrations for customers and partners Incorporate compliance and regulatory considerations relevant to the Accounting Platform … focusing on core financial, accounting, or transactional platforms Deep subject matter expertise in accounting principles, particularly related to payment processing, transaction records, and financial reconciliation Strong practical understanding of API design, documentation, and externalisation Proven ability to work with legal and compliance teams to translate regulatory requirements into technical specifications A track record of making and validating impact More ❯

impact our product, contribute to our internal ecosystem, and thrive in a dynamic, collaborative startup environment. Location: Remote Why this role is remarkable: Work directly with founders, product, and design to build and iterate on cutting-edge features for a fast-growing AI startup. Play a pivotal role throughout the entire feature lifecycle, from initial concept to execution, deployment … years of professional experience in Frontend development, with sustained experience in frameworks like React, Vue.js, or Angular. Demonstrates a solid understanding of version control (Git) and knowledge of RESTful API design and implementation. Exhibits strong problem-solving skills and adaptability, thriving in a fast-paced startup environment with excellent communication. How to Apply: To apply for this job More ❯

Linux tuning, performance profiling Background in designing high-performance architectures and distributed systems Strong grasp of FX pricing, risk, and trading workflows Solid engineering fundamentals: testing, CI/CD, API design, automation Why join? Work on mission-critical systems powering global trading Highly technical culture with genuine ownership and impact Flexibility in working hours and hybrid setup More ❯

their potential applications. Develop clear and effective data models and supporting documentation. Write and maintain user stories for large development and testing teams. Define and document data requirements and API specifications . Collaborate closely with cross-functional teams in an Agile/Scrum environment to ensure successful delivery. Essential Skills & Experience Strong core business analysis capabilities, including requirements definition … and stakeholder management. Demonstrated experience in data modelling , API documentation , and digital service delivery . Proven success working within Agile/Scrum frameworks and contributing to high-performing agile teams . Proficiency with Jira and other agile delivery tools. Prior experience working within the public sector (central or local government). Solid understanding of digital delivery practices in government … or similar settings. Desirable Knowledge Awareness of Generative AI tools and their potential applications. Experience defining and managing data requirements across large-scale systems. Familiarity with API design and documentation standards. If you're an experienced Business Analyst looking to make an impact within a digital transformation environment, we'd love to hear from you. More ❯

Have deep familiarity with Python data ecosystem Understanding of Jupyter notebooks Exposure to machine learning libraries like PyTorch, XGBoost and JAX Understanding of crypto or traditional financial markets Strong API design and documentation skills What do you get in return? Up to 250k base (depending on experience) 3 days in their new central London office Pension scheme More ❯

Have deep familiarity with Python data ecosystem Understanding of Jupyter notebooks Exposure to machine learning libraries like PyTorch, XGBoost and JAX Understanding of crypto or traditional financial markets Strong API design and documentation skills What do you get in return? Up to £250k base (depending on experience) 3 days in their new central London office Pension scheme More ❯

technologies like the Model Context Protocol (MCP) to enhance how services interact with AI models and automate integration flows. You'll lead through hands-on engineering - writing code, guiding design, and mentoring others - while shaping the evolution of MSCI's secure, intelligent, and scalable platform ecosystem. Join us to build the foundation for MSCI's AI-enabled future. Your … and secure scalability across our global platforms. We're seeking a Senior Technical Lead who combines deep engineering expertise with architectural vision to help drive this transformation. You'll design and deliver microservices and APIs that power next-generation platform capabilities - including AI-assisted workflows, automated integration patterns, and model interaction layers built with the Model Context Protocol (MCP … the intersection of cloud infrastructure, intelligent automation, and modern application design. Architect and build scalable, secure microservices in Go, Node.js, or Java, powering new platform and AI integration capabilities. Design and deliver cloud-native services that leverage AI models and context-aware APIs to improve system intelligence and automation. Collaborate globally with product, architecture, and AI teams to identify More ❯

fast-moving environment. Your Skills and Experience 6+ years of experience in backend systems, with 1–3 years in engineering management or strong technical leadership roles Proven ability to design, build, and scale platform systems, owning complex projects from architecture to production Strong experience with cloud-based distributed systems, including architectural decision-making, deployment strategies, and operational excellence Advanced … backend development skills with an emphasis on API design, scalability, observability, and monitoring Experience mentoring engineers and promoting high technical standards within fast-growing teams Excellent communication skills with the ability to collaborate across engineering, product, and cross-functional groups Interest in, or exposure to, ML model serving, GPU-based infrastructure, or ML platform tooling (preferred but not More ❯

Solution Architect - Client-facing TypeScript API Design Hybrid (2 Days Onsite in Central London) £105,000-£110,000 + 15% Discretionary Bonus Method Resourcing is thrilled to be partnering with a global leader in the travel industry who are hiring a Client-facing Solution Architect to join a high-performing architectural team click apply for full job details More ❯

research teams in software engineering, computer vision, machine learning and graphics to write software for SnapOS, the operating system for Spectacles Knowledge, Skills & Abilities: Strong knowledge of C++ and API design Experience with leading an engineering team working on large, complex technical initiatives Ability to collaborate with internal stakeholders at all levels of a company Strong communication and More ❯

Stack Software Engineer to join a leading global investment management firm in London. Paying up to 120k plus bonus per annum, you will contribute to the development, optimisation, and design of front-office applications, collaborating with portfolio managers and product owners to create innovative and high-performance solutions. As a Senior Full Stack Software Engineer, you will play a … React) with a focus on UI/UX. Proven backend expertise, particularly with Java (Python, Node.js a plus), and experience building distributed microservices-based architectures. Strong knowledge of system design principles, scalable architecture patterns, and API design. Hands-on experience with relational (Postgres, MySQL) and NoSQL (DynamoDB) databases. Proficiency in cloud platforms (AWS, Azure, or GCP). Experience More ❯

and validation processes. Identify and mitigate risks associated with migration and system cutover. Core Skills & Experience: Proven expertise in PAS systems and complex data migration projects. Strong knowledge of API design and integration . Advanced data modelling skills for structured and semi-structured data. Proficiency in XML, JSON, and Excel for data handling and transformation. Ability to work More ❯

Technical Business Analyst - London/Remote (Technical Business Analyst, Technical BA, Business Analyst, BA, Technical Analyst, Systems Analyst, Solutions Architect, API Designers, Systems Analysts, RESTful APIs, Web APIs, JIRA, Confluence, user stories, JSON, Open API Specification, Swagger, HTTP, Agile, SQL) Our client is an exciting and cutting-edge fintech giant with a global presence. They have been a … their worldwide client base has never been stronger, with significant growth in the last 12 months. They are looking for a Technical Business Analyst with a background designing RESTful API services in fast-paced development teams, to work on consulting projects and help to align information technology with business operations and processes. We are seeking an Technical Business Analyst … Restful APIs, data models and event-driven processes for development teams. You will also need to be comfortable in HTTP, JIRA/Confluence, user stories, JSON Schema and Open API Specification (Swagger). Excellent Agile and SQL is expected, as is experience in Postman, BPMN and Gherkin. Exceptional communication and interpersonal skills are a must, as is the ability More ❯