9 api developer jobs found

Lead .NET/Full Stack Developer - Hybrid - £700/day Outside IR35 | C# | Azure | Event Driven Systems | Payments | API Driven We have a unique opportunity for a Lead .NET/Full Stack Developer to join a payments company. As the Lead .NET/Full Stack Developer , you’ll play a key role in shaping and scaling a high-throughput payments platform as the business enters its next phase of growth. This includes launching new products, enabling new partner integrations, and expanding a platform that already powers multiple live financial services products used globally. You’ll be building on top of a modern, cloud-native platform built with .NET and Azure , designed around API-first architecture and event-driven microservices . The platform supports complex payment flows, partner integrations, and high-volume transaction processing. This is a hands-on technical role where you’ll help drive engineering best practices, contribute to architectural decisions, and mentor...

Full Stack Developer (React/TypeScript/Java) Location: London (1-2 days onsite per month) Contract: Outside IR35 Rate: £650-£700 per day Duration: 12 Month Contract Start: Immediate/Short Notice Preferred Eligibility: Active SC Clearance required (DV clearance ideally) Overview An experienced Full Stack Developer is required to build and maintain scalable, high-performance applications within a secure public sector environment. The role requires a 50/50 split across Front End and Back End development . Requirements Strong experience with React and TypeScript Solid Java Back End development experience Experience working in a full stack capacity (approx. 50/50 Front End/Back End) Strong understanding of API integration and system design Active SC Clearance required (DV clearance ideally)

Fullstack Developer – Palantir Foundry job in London – £750 - £1000 a day – London – Outside IR35 Hexwired Recruitment is recruiting for an expanding Solutions provider, now seeking Data Engineers and Fullstack Developers with solid experience working on Palantir Foundry’s data analytics dashboard. You will be working on the full product lifecycle for a range of customers within Finance, energy and more. The successful candidate must have good experience on both the API development and backend data management side of Palantir’s products. Initial 3 months with very likely extension. Outside IR35 and will require at least 3 days onsite. Key Skills: Bachelors in CS, Maths, Physics or similar 3+ commercial Palantir Foundry dashboard experience Solid experience building applications using Palantir Foundry Excellent Data Engineering experience using Palantir Foundry Company is agnostic on programming languages, Python, Java, Typescript and/or React...

Contract Senior Java Developer – Data Up to £700 per day Outside IR35 (6 month rolling) In office – City of London Quant Capital is hiring for a small, high-performing market maker in London. This is a junior-to-mid role focused primarily on Java development, with a secondary responsibility owning straightforward Python ETL/data ingestion into AWS and PostgreSQL. This is a growing team focused on data ingestion and building tooling for the wider firm. What you’ll do: Build and enhance Java backend services (APIs, batch jobs, integrations) used across the business Write clean, testable code with solid engineering discipline (testing, code review, debugging, production support) Maintain and extend Python-based ingestion/ETL (pragmatic plumbing, not heavy data engineering) Work with PostgreSQL (schemas, migrations, performant queries, data validation) Improve service reliability: monitoring/logging, sensible alerting, and predictable deployments via CI/CD...

IT Applications Manager - Central London £650 - £700 p/d (outside IR35) - 3 month initial term Well-established and highly profitable construction engineering business is seeking an experienced IT Applications Manager to join them on a permanent basis. This is a critical leadership role within an organisation undergoing significant digital transformation, with ambitious growth and acquisition plans driving demand for scalable, standardised and efficient business applications. Reporting into the Head of IT, you will lead the delivery, governance and optimisation of business applications across the enterprise. This role blends strategic oversight, hands-on expertise with modern low-code/no-code platforms and direct leadership of a multidisciplinary applications team. The IT Applications Manager will oversee a suite of core enterprise systems, including but not limited to: Workday, UKG (Kronos), COINS, SharePoint, Snowflake, Autodesk Construction Cloud, Pro-Sapien,...

IT Applications Manager - Central London (hybrid) £650 - £700 p/d (outside IR35) 3 month initial term, likely to extend Well-established and highly profitable construction engineering business is seeking an experienced IT Applications Manager to join them on a permanent basis. This is a critical leadership role within an organisation undergoing significant digital transformation, with ambitious growth and acquisition plans driving demand for scalable, standardised and efficient business applications. Reporting into the Head of IT, you will lead the delivery, governance and optimisation of business applications across the enterprise. This role blends strategic oversight, hands-on expertise with modern low-code/no-code platforms and direct leadership of a multidisciplinary applications team. The IT Applications Manager will oversee a suite of core enterprise systems, including but not limited to: Workday, UKG (Kronos), COINS, SharePoint, Snowflake, Autodesk...

IFS Cloud Consultant £600 - £700 per day | Outside IR35 Initial 12-month contract Hybrid role - St Albans (site presence required) IFS Cloud Consultant - Outside IR35 - St Albans TalentBank Technology is supporting a leading organisation within the energy and utilities sector to engage an experienced IFS Cloud Consultant on an initial 12-month contract. This role combines technical leadership, hands-on delivery, and functional expertise across a globally distributed IFS Cloud platform. The successful consultant will work closely with IT leaders, developers, architects, and functional teams to drive platform standardisation, technical excellence, and governance across security, data management, release management, and environment management. Key Responsibilities Define and implement best practices for IFS Cloud security and permissions architecture. Lead release and deployment management including updates, patches, integrations, and configurations. Oversee...

IT Applications Manager - Central London £650 - £700 p/d (outside IR35) - 3 month initial term Well-established and highly profitable construction engineering business is seeking an experienced IT Applications Manager to join them on a permanent basis. This is a critical leadership role within an organisation undergoing significant digital transformation, with ambitious growth and acquisition plans driving demand for scalable, standardised and efficient business applications. Reporting into the Head of IT, you will lead the delivery, governance and optimisation of business applications across the enterprise. This role blends strategic oversight, hands-on expertise with modern low-code/no-code platforms and direct leadership of a multidisciplinary applications team. The IT Applications Manager will oversee a suite of core enterprise systems, including but not limited to: Workday, UKG (Kronos), COINS, SharePoint, Snowflake, Autodesk Construction Cloud, Pro-Sapien, Primavera P6...

Role: Expert .NET Developer – Cross Asset Trading System Location: Very Flexible. Can offer Remote with occasional travel to London City offices Contract: 12 months Rate: Up to £750/day (OUTSIDE IR35) About the Role: We are partnering with a leading investment bank on an ambitious programme to modernise and enhance their cross-asset trading systems. This is a technically challenging, hands-on role, ideal for an expert .NET developer with a strong SQL Server background and experience working in financial environments. You will be joining a highly skilled team focused on performance, reliability, and scalability, tackling complex issues in real-time, data-driven applications. This is purely a tech-heavy role—business knowledge is helpful but not required. What You’ll Be Doing: Design, develop, and maintain RESTful APIs using .NET technologies (C#, ASP.NET Core). Redesigning and refactoring high-activity tables to improve performance and...