26 to 50 of 81 API Design Jobs in London

Software Engineer III (UI) - Digital Markets Execution Technology (DMET), Execute

Hiring Organisation
J.P. MORGAN
Location
Westminster, Greater London, UK
Employment Type
Full-time
your application. \n JOB DESCRIPTION \n As a Software Engineer III at JPMorganChase, you serve as a seasoned member of an agile team to design and deliver trusted market-leading technology products in a secure, stable, and scalable way. You are responsible for carrying out critical technology solutions across … measured by resiliency, usability, and speed of delivery in a highly operational, business-critical environment. \n Job Responsibilities \n \n Executes software solutions, design, development, and technical troubleshooting with ability to think beyond routine or conventional approaches to build solutions or breakdown technical problems \nCreates secure and high-quality ...

Senior Application Security Engineer - DevSecOps & Cloud Security

Hiring Organisation
Additional Resources
Location
London, United Kingdom
Employment Type
Permanent
Salary
£70000 - £80000/annum
applications, platforms and deployment processes. This is not a traditional vulnerability management role, it is a hands-on Application Security role centred on secure design, CI/CD security, cloud-native technologies, Kubernetes, API security, code analysis, security-as-code and supporting development teams to build secure applications. … controls throughout CI/CD pipelines. Strengthening the security of GitHub Actions and comparable continuous integration and deployment platforms. Providing technical guidance on secure API design and protecting externally accessible systems. Supporting the security of Azure cloud infrastructure, including Azure Kubernetes Service (AKS). Assisting with the protection ...

Senior Solutions Engineer

Hiring Organisation
Wise
Location
Greater London, United Kingdom
Employment Type
Full Time
Salary
87500 to 111000 GBP Annually
team works with top tier global financial institutions and major tech companies to offer Wise products and services directly to their customers. Through our API, we help partners to architect and build integrations to our world class-leading international finance products, which in turn improves Wise Platform by increasing … improve turnaround times. Designing and developing innovative new features that expand the functionality of Wise's services and exposing these features through the public API, enabling seamless integration with partner systems and empowering them to leverage the full potential of Wise's platform. Diagnosing and resolving complex technical issues ...

Senior Solutions Engineer

Hiring Organisation
WISE
Location
Westminster, Greater London, UK
Employment Type
Full-time
works with top tier global financial institutions and major tech companies to offer Wise products and services directly to their customers. \n Through our API, we help partners to architect and build integrations to our world class-leading international finance products, which in turn improves Wise Platform by increasing … improve turnaround times. Designing and developing innovative new features that expand the functionality of Wise's services and exposing these features through the public API, enabling seamless integration with partner systems and empowering them to leverage the full potential of Wise's platform. Diagnosing and resolving complex technical issues ...

Engineering Lead, Scale

Hiring Organisation
Jobleads-UK
Location
Greater London, England, United Kingdom
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 ...

Dell Boomi Integration Consultant

Hiring Organisation
Oscar Associates (UK) Limited
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
£500 - £550 per day
Boomi AtomSphere, connecting multiple enterprise platforms across cloud and on-premise environments. This is a hands-on technical position requiring strong Boomi development experience, API integration knowledge and the ability to support complex integration landscapes. Key Responsibilities: Design and develop scalable integration solutions using Dell Boomi AtomSphere, including … secure Managed File Transfer (MFT) workflows to support high-volume and sensitive data transfers Publish, secure and govern REST/SOAP APIs through Boomi API Management, including gateway configuration, throttling and developer portal management Develop and maintain CI/CD pipelines using Git, Azure DevOps or Jenkins, supporting automated ...

Tech Lead / Senior Software Engineer / Software Architect

Hiring Organisation
Intec Select Ltd
Location
London, Portsoken, United Kingdom
Employment Type
Permanent
Salary
£80000 - £110000/annum
Tech Lead, Senior Software Engineer or Software Architect who enjoys solving complex technical problems and building modern, scalable software. Role & Responsibilities Lead the technical design and evolution of a large-scale business-critical platform. Improve the existing architecture and define a pragmatic roadmap towards a modern, scalable solution. Design … powered capabilities into the product to improve functionality and user experience. Drive the adoption of AI-assisted software development tools and engineering best practices. Design integrations with enterprise platforms, APIs and wider business systems. Work closely with Product, Architecture and Engineering teams to deliver incremental improvements. Mentor developers ...

Full Stack Developer

Hiring Organisation
Robert Half
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
Salary negotiable
this is an opportunity to help shape the future of a rapidly evolving platform. Role The Full Stack Developer will contribute to full-stack design and development across the platform. Design, develop, and maintain both front-end user interfaces and back-end services, APIs, and databases. Monitor platform … strong focus on backend development. Bachelor's or Master's degree in Computer Science, Engineering, or a related discipline. Strong understanding of database design, data modelling, and optimisation, particularly using SQL. Hands-on experience working with Google Cloud Platform (GCP) services. Experience monitoring production systems, triaging issues, and distinguishing ...

Senior Python Backend Engineer Fully Remote, UK

Hiring Organisation
Interact Consulting Limited
Location
South West London, London, United Kingdom
Employment Type
Permanent, Work From Home
enjoys building from the ground up. The salary range is up to £120,000 depending on experience and fit. Key Responsibilities Own the design, development, and operation of the core backend services that power our consumer-facing products and internal operational tooling. Build scalable, low-latency systems that … notification preferences, audience segmentation, and delivery tracking. Integrate with third-party data providers and external services, ensuring robust failure handling, observability, and system resilience. Design and support secure internal tooling APIs, including role-based access controls, audit trails, change history, and safe administrative workflows. Build and operate event-driven ...

Staff Software Engineer, Scale

Hiring Organisation
Jobleads-UK
Location
Greater London, England, United Kingdom
regulatory, and technical domains—areas where no single existing team has full coverage, like tax systems, compliance-driven flows, or monetization tools. Solutions Architecture: Design integrations for enterprise prospects by translating their business requirements into technical solutions. Your architectural decisions directly influence deal outcomes—from enabling multi-million dollar … 8+ for Staff) in Java/Spring Boot Excel at making the right level of abstraction—balancing flexibility and simplicity in system/component design Demonstrate clean communication across technical and non-technical stakeholders Make pragmatic decisions on when to optimize for performance vs. velocity based on business impact ...

Director, Forward Deployed Engineering

Hiring Organisation
Jobleads-UK
Location
Greater London, England, United Kingdom
lead a team of elite engineers who embed directly with Fortune 500 customers to ship deeply integrated AI agents—owning everything from agent design and evaluation to the backend services, data systems, and cloud infrastructure that make them production‐ready. You'll partner closely with our Forward Deployed … volume for senior engineering roles. Hands‐on fluency with the full AI stack. Deep familiarity with LLMs and agent systems, evaluation frameworks, backend and API design (Python or TypeScript), data systems (PostgreSQL, DynamoDB, MongoDB, or similar), and cloud infrastructure (AWS, Azure, or GCP) including Kubernetes, Docker ...

C# .Net Developer

Hiring Organisation
Pontoon
Location
Bromley, Kent, England, United Kingdom
Employment Type
Contractor
Contract Rate
£700 - £750 per day
Chicago). The role offers the opportunity to contribute to business-critical systems while working in a collaborative and supportive environment. Key Responsibilities Design, develop, enhance, and maintain enterprise applications using C# and .NET technologies. Support and improve existing business-critical systems, ensuring stability, performance, and scalability. Work closely … with business users, analysts, and technical teams to gather requirements and deliver solutions. Participate in the full software development lifecycle, including design, development, testing, deployment, and support. Collaborate with globally distributed development teams across multiple locations and time zones. Contribute to technical discussions, solution design, code reviews ...

C# .NET Developer

Hiring Organisation
Pontoon
Location
Bromley, London, South Yorkshire, United Kingdom
Employment Type
Contract
Contract Rate
£650 - £750/day Inside IR35
Chicago). The role offers the opportunity to contribute to business-critical systems while working in a collaborative and supportive environment. Key Responsibilities Design, develop, enhance, and maintain enterprise applications using C# and .NET technologies. Support and improve existing business-critical systems, ensuring stability, performance, and scalability. Work closely … with business users, analysts, and technical teams to gather requirements and deliver solutions. Participate in the full software development lifecycle, including design, development, testing, deployment, and support. Collaborate with globally distributed development teams across multiple locations and time zones. Contribute to technical discussions, solution design, code reviews ...

UI Senior Lead Software Engineer - Commodities

Hiring Organisation
J.P. MORGAN
Location
Westminster, Greater London, UK
Employment Type
Full-time
This role emphasizes engineering excellence, operational readiness, and secure, compliant delivery in a fast-paced global environment. \n Job Responsibilities \n \n Lead the design and delivery of user interface capabilities across Execute, from discovery to production support \nSet front-end technical direction, including architecture, standards, performance, and testing … technical leadership in setting standards, leading designs, and directly managing or mentoring small teams of mid-level engineersSolid software engineering fundamentals, including OO/design patterns, debugging, and documentationFamiliarity with agentic development approaches across the software development lifecycleStrong communication and people skills, with the ability to work effectively ...

Senior Backend Python Engineer

Hiring Organisation
Interact Consulting Limited
Location
South West London, London, United Kingdom
Employment Type
Permanent, Work From Home
What were looking for: Hands-on experience running real production workloads on AWS not just deploying to it Strong Postgres/SQL skills: schema design, query tuning, migrations Solid API design chops: clear contracts, versioning, backwards compatibility Python-first mindset (FastAPI or similar) Redis experience: caching patterns ...

Lead Software Engineer

Hiring Organisation
Intec Select Ltd
Location
London, Billingsgate, United Kingdom
Employment Type
Permanent
Tech Lead, Senior Software Engineer or Software Architect who enjoys solving complex technical problems and building modern, scalable software. Role & Responsibilities Lead the technical design and evolution of a large-scale business-critical platform. Improve the existing architecture and define a pragmatic roadmap towards a modern, scalable solution. Design … powered capabilities into the product to improve functionality and user experience. Drive the adoption of AI-assisted software development tools and engineering best practices. Design integrations with enterprise platforms, APIs and wider business systems. Work closely with Product, Architecture and Engineering teams to deliver incremental improvements. Mentor developers ...

Lead Software Engineer (UI) - Digital Markets Execution Technology (DMET), Execute

Hiring Organisation
J.P. MORGAN
Location
Westminster, Greater London, UK
Employment Type
Full-time
This role emphasizes engineering excellence, operational readiness, and secure, compliant delivery in a fast-paced global environment. \n Job Responsibilities \n \n Lead the design and delivery of user interface capabilities across Execute, from discovery to production support \nSet front-end technical direction, including architecture, standards, performance, and testing … delivering real-time or data-intensive user experiencesDemonstrated technical leadership in setting standards, leading designs, and mentoring teamsSolid software engineering fundamentals, including OO/design patterns, debugging, and documentationFamiliarity with agentic development approaches across the software development lifecycleStrong communication skills and ability to work effectively in global, cross-functional ...

Software Engineer

Hiring Organisation
Corpay
Location
Central London, London, United Kingdom
Employment Type
Permanent, Work From Home
division. This position falls under our Cross Border line of business and is located in London. In this role, you will contribute to the design and development of our eMoney and FX payment systems. You will report directly to the Engineering Manager and collaborate closely with Product, Design … will set you up for success by providing: Assigned workspace or home office setup Company-issued equipment Role Responsibilities Provide significant contribution to the design, development, and maintenance of secure and scalable payment systems. Collaborate with engineering managers, designers, and product teams to gather and analyse requirements, implement technical ...

Junior FullStack Developer

Hiring Organisation
Randstad Technologies Recruitment
Location
London, United Kingdom
Employment Type
Permanent
Salary
£40000 - £45000/annum
features-you will be building impactful, user-facing applications from day one. Working closely with the founding team, you will help architect robust APIs, design intuitive frontend interfaces, and integrate cutting-edge AI/ML models into our core product. Qualifications & Experience Essential: 0-2 years of hands … projects). Education: A degree in Computer Science, Information Technology, or a related discipline. Core Fundamentals: A solid grounding in web development fundamentals, REST API design, and secure coding practices. Frontend: Proficiency in React and TypeScript, with a clear sense of how to build maintainable component hierarchies. Backend ...

Back End Development Lead

Hiring Organisation
Oyster Consultants
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
£60,000 - £75,000 per annum
evolve our stack and make constant improvements. Required Skills/Experience Strong C# development experience Experience with both .NET Core and .NET Web API Experience of building Microservices in .Net Core Experience using Message Based Architectures Experience using both SQL & NoSQL technologies Experience of API design Cloud ...

Senior Software Engineer – Data Visualisation & Graphics | London

Hiring Organisation
techstack Recruitment
Location
City of London, London, United Kingdom
working on the underlying systems that make complex visualisations fast, accurate, and scalable. The challenges range from rendering performance and interaction design through to algorithms, graphics, API design, and numerical correctness. What you’ll be doing Designing and building core charting features used by developers around … exceptionally high technical standards High levels of ownership and autonomy Small team, significant impact Opportunity to deepen expertise in performance, graphics, visualisation, and systems design Package Salary up to £200,000 Hybrid working (London) Private healthcare Pension Additional benefits If you’re interested in building the technology behind modern ...

Pre-Sales Technical Architect for SaaS Integrations

Hiring Organisation
Jobleads-UK
Location
Greater London, England, United Kingdom
client data will be sourced, validated, and integrated into Mondra, leveraging where possible our existing Import and Export APIs and identifying where custom API development may be required for fulfil Mondra’s data requirements. You will also contribute to the client contracting process, ensuring technical commitments are clearly defined … including mapping data sources, transformation logic, and validation processes. Identify the client’s BI requirements, and define data export strategies (preferably via existing Mondra API). Identify the authentication/authorisation capabilities of the client, and promote the integration with Mondra’s Identity Provider via Single Sign On. Leverage ...

Senior Product Engineer - Partner Experience

Hiring Organisation
Wise
Location
Greater London, United Kingdom
Employment Type
Full Time
Salary
87500 to 111000 GBP Annually
work: We're a small team that ships frequently and iterates on real partner feedback. Engineers own features from technical discovery and design through to production support. We work closely with our PM and designer to understand partner needs, and with adjacent teams (API Experience, Account Discovery … identity mapping between partner systems and Wise. • The communication layer services between Wise and partners, extending them to handle new case types and workflows. • API design for partner-facing endpoints. We care about consistency, documentation, and making them usable without hand-holding. • Work with FinCrime, Compliance ...

Senior Product Engineer - Partner Experience

Hiring Organisation
WISE
Location
Westminster, Greater London, UK
Employment Type
Full-time
work: \n We're a small team that ships frequently and iterates on real partner feedback. Engineers own features from technical discovery and design through to production support. We work closely with our PM and designer to understand partner needs, and with adjacent teams (API Experience, Account Discovery … between partner systems and Wise. \n • The communication layer services between Wise and partners, extending them to handle new case types and workflows. \n • API design for partner-facing endpoints. We care about consistency, documentation, and making them usable without hand-holding. \n • Work with FinCrime, Compliance ...

Full Stack Engineer

Hiring Organisation
Randstad Technologies Recruitment
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
£550 - £700/day
Data & ML Pipelines: Model data for strict auditability, versioning, and efficient querying, feeding structured datasets directly into downstream machine learning models. Empower Internal Teams: Design and implement intuitive, responsive web interfaces that allow non-technical stakeholders (Legal, Operations, Trust & Safety) to author and manage content policies with robust approval … services using Java, Kotlin, or Go . Modern Frontend Skills: Hands-on experience building clean, intuitive internal tooling using React and TypeScript . System Design & Integrity: Deep understanding of API design, backward compatibility, and data modeling for complex, versioned systems where stability is critical. Data Savvy: Experience ...