Date posted
Commute time
Locations
Type of Company
Job types
Salaries
Locations
Locations
Salaries
Date posted
Type of Company
Job types
Locations
4 Contract API jobs in Hemel Hempstead + 20 miles
273 exact matches jobs are outside your preferred location
)
I am currently working with a London-based Tier 1 investment bank who are actively seeking a Python Developer on a long-term contract basis. What you'll need to succeed * Strong Python programming experience within Financial Services - Mandatory * Good understanding of quantitative finance * Good experience developing and optimising Python-based calculators and models. * Strong experience developing high-performance APIs using Flask or FastAPI. * Expertise in Pandas, NumPy and other computing libraries. * Strong experience liaising with front-office stakeholders - What you'll get in return * Initial 6-month contract with extensions * Up to £700pd umbrella * London-based hybrid working - What you need to do nowIf you're interested in this role, click 'apply now' to forward an up-to-date copy of your CV, or call us now.
I am currently working with a London-based Tier 1 investment bank who are actively seeking a Python Developer on a long-term contract basis. What you'll need to succeed * Strong Python programming experience within Financial Services - Mandatory * Good understanding of quantitative finance * Good experience developing and optimising Python-based calculators and models. * Strong experience developing high-performance APIs using Flask or FastAPI. * Expertise in Pandas, NumPy and other computing libraries. * Strong experience liaising with front-office stakeholders - What you'll get in return * Initial 6-month contract with extensions * Up to £700pd umbrella * London-based hybrid working - What you need to do nowIf you're interested in this role, click 'apply now' to forward an up-to-date copy of your CV, or call us now.
NEW
)
Company Description - At The Stepstone Group, we have a simple yet very important mission: The right job for everyone. Using our data, platform, and technology, we create opportunities for jobseekers and companies around the world to find a perfect match in fair and equitable way. With over 20 brands across 30+ countries, we strive for fair and unbiased hiring. Join our team of 4,000+ employees and be part of reshaping the labour market and becoming the worlds leading job platform. Job Description - Join our team and youll be responsible for providing technical leadership to all engineering and development areas across your domain, developing and executing an engineering strategy aligned to the portfolio and global tech strategies. Working in the Design and Platform Performance domain, you willlead the technology side of web and mobile analytics for a platform with ov
Company Description - At The Stepstone Group, we have a simple yet very important mission: The right job for everyone. Using our data, platform, and technology, we create opportunities for jobseekers and companies around the world to find a perfect match in fair and equitable way. With over 20 brands across 30+ countries, we strive for fair and unbiased hiring. Join our team of 4,000+ employees and be part of reshaping the labour market and becoming the worlds leading job platform. Job Description - Join our team and youll be responsible for providing technical leadership to all engineering and development areas across your domain, developing and executing an engineering strategy aligned to the portfolio and global tech strategies. Working in the Design and Platform Performance domain, you willlead the technology side of web and mobile analytics for a platform with ov
NEWEQUALITY BOOST
Halian Technology are searching for aLead Android Engineerto join our clients forward-thinking mobile team. Our client isone of the UKs most trusted and innovative omni-channel retailers, where technology and customer experience go hand in hand. If youre passionate about delivering high-quality mobile experiences and want to work with modern tools, great people, and at a company where learning and development are core valuesthis is the role for you. * Influence architecture and development strategy within a high-performing Agile squad. * Provide technical assurance and guidance across complex, high-impact projects. * Collaborate cross-functionally with iOS Engineers, BAs, QAs, Designers, and UX Specialists. * Champion Android best practices including Accessibility, CI/CD, TDD, and clean architecture.
Halian Technology are searching for aLead Android Engineerto join our clients forward-thinking mobile team. Our client isone of the UKs most trusted and innovative omni-channel retailers, where technology and customer experience go hand in hand. If youre passionate about delivering high-quality mobile experiences and want to work with modern tools, great people, and at a company where learning and development are core valuesthis is the role for you. * Influence architecture and development strategy within a high-performing Agile squad. * Provide technical assurance and guidance across complex, high-impact projects. * Collaborate cross-functionally with iOS Engineers, BAs, QAs, Designers, and UX Specialists. * Champion Android best practices including Accessibility, CI/CD, TDD, and clean architecture.
NEW
Halian Technology are searching for aLead Android Engineerto join our clients forward-thinking mobile team. Our client isone of the UKs most trusted and innovative omni-channel retailers, where technology and customer experience go hand in hand. If youre passionate about delivering high-quality mobile experiences and want to work with modern tools, great people, and at a company where learning and development are core valuesthis is the role for you. * Influence architecture and development strategy within a high-performing Agile squad. * Provide technical assurance and guidance across complex, high-impact projects. * Collaborate cross-functionally with iOS Engineers, BAs, QAs, Designers, and UX Specialists. * Champion Android best practices including Accessibility, CI/CD, TDD, and clean architecture.
Halian Technology are searching for aLead Android Engineerto join our clients forward-thinking mobile team. Our client isone of the UKs most trusted and innovative omni-channel retailers, where technology and customer experience go hand in hand. If youre passionate about delivering high-quality mobile experiences and want to work with modern tools, great people, and at a company where learning and development are core valuesthis is the role for you. * Influence architecture and development strategy within a high-performing Agile squad. * Provide technical assurance and guidance across complex, high-impact projects. * Collaborate cross-functionally with iOS Engineers, BAs, QAs, Designers, and UX Specialists. * Champion Android best practices including Accessibility, CI/CD, TDD, and clean architecture.
NEW
)
Full Stack Developer Node.Js / React
Full Stack Developer Node.Js / React
Halian Technology Limited
W1, Central London
From £60,000 to £65,000 per annum Plus bonus and benefits
My client specialises in digital payments across the UK and Europe. Their platform enables seamless real-time transactions for consumers and businesses, with a focus on security, scalability, and user experience. Backed by top-tier investors and used by thousands daily, were scaling up and looking for passionate engineers to help us build the future of payments. We are seeking a talented and driven Mid-Level Full Stack Engineer with strong skills in Node.js, React, and AWS cloud infrastructure. Youll play a key role in designing, developing, and maintaining scalable microservices and user interfaces for our core payments platform. Youll work in a cross-functional agile team alongside product managers, designers, and fellow engineers to deliver features that directly impact our customers and partners. * Develop backend microservices using Node.js (Express/Nest.js prefe
My client specialises in digital payments across the UK and Europe. Their platform enables seamless real-time transactions for consumers and businesses, with a focus on security, scalability, and user experience. Backed by top-tier investors and used by thousands daily, were scaling up and looking for passionate engineers to help us build the future of payments. We are seeking a talented and driven Mid-Level Full Stack Engineer with strong skills in Node.js, React, and AWS cloud infrastructure. Youll play a key role in designing, developing, and maintaining scalable microservices and user interfaces for our core payments platform. Youll work in a cross-functional agile team alongside product managers, designers, and fellow engineers to deliver features that directly impact our customers and partners. * Develop backend microservices using Node.js (Express/Nest.js prefe
NEW
)
*outside iR35* What You'll Be Doing * Designing and developing enterprise-grade solutions in an Agile team. * Building and maintaining middleware services using C#, REST APIs, FIX messaging, XML, and Microservices. * Leading architecture discussions, code reviews, and release management. * Collaborating with users and cross-functional teams to define and execute testing strategies. * Mentoring junior developers and contributing to internal best practices. What You Bring * A strong academic background in Computer Science, Engineering, or a related field. * Proven experience in commodities trading, especially with derivatives and platforms like ICE, CME, NASDAQ, Trayport, or TT. * Deep knowledge of C# .NET, RESTful services, and microservice architecture. * Hands-on experience with FIX messaging, XML, AMQ, and ideally nHibernate, OData, and TDD.
*outside iR35* What You'll Be Doing * Designing and developing enterprise-grade solutions in an Agile team. * Building and maintaining middleware services using C#, REST APIs, FIX messaging, XML, and Microservices. * Leading architecture discussions, code reviews, and release management. * Collaborating with users and cross-functional teams to define and execute testing strategies. * Mentoring junior developers and contributing to internal best practices. What You Bring * A strong academic background in Computer Science, Engineering, or a related field. * Proven experience in commodities trading, especially with derivatives and platforms like ICE, CME, NASDAQ, Trayport, or TT. * Deep knowledge of C# .NET, RESTful services, and microservice architecture. * Hands-on experience with FIX messaging, XML, AMQ, and ideally nHibernate, OData, and TDD.
)
*outside iR35* What You'll Be Doing * Designing and developing enterprise-grade solutions in an Agile team. * Building and maintaining middleware services using C#, REST APIs, FIX messaging, XML, and Microservices. * Leading architecture discussions, code reviews, and release management. * Collaborating with users and cross-functional teams to define and execute testing strategies. * Mentoring junior developers and contributing to internal best practices. What You Bring * A strong academic background in Computer Science, Engineering, or a related field. * Proven experience in commodities trading, especially with derivatives and platforms like ICE, CME, NASDAQ, Trayport, or TT. * Deep knowledge of C# .NET, RESTful services, and microservice architecture. * Hands-on experience with FIX messaging, XML, AMQ, and ideally nHibernate, OData, and TDD.
*outside iR35* What You'll Be Doing * Designing and developing enterprise-grade solutions in an Agile team. * Building and maintaining middleware services using C#, REST APIs, FIX messaging, XML, and Microservices. * Leading architecture discussions, code reviews, and release management. * Collaborating with users and cross-functional teams to define and execute testing strategies. * Mentoring junior developers and contributing to internal best practices. What You Bring * A strong academic background in Computer Science, Engineering, or a related field. * Proven experience in commodities trading, especially with derivatives and platforms like ICE, CME, NASDAQ, Trayport, or TT. * Deep knowledge of C# .NET, RESTful services, and microservice architecture. * Hands-on experience with FIX messaging, XML, AMQ, and ideally nHibernate, OData, and TDD.
)
Lead Salesforce Developer Contract (Outside IR35) Fully Remote - Day Rate: Competitive, open to negotiation - Duration: 6 months+ Working Arrangements: Fully Remote - Interview: 1 Video Call - About the Role - We are seeking an experienced Lead Salesforce Developer for a hands-on leadership role within a fast-growing, innovative financial services environment. You will take ownership of the Salesforce platform, leading a small, talented team and driving technical excellence across the business. What Youll Do * Lead the design, development, and deployment of Salesforce solutions * Collaborate with stakeholders to gather requirements and deliver tailored functionality * Manage and mentor a team of Salesforce professionals (Administrators, Analysts, and Developers) * Ensure data integrity, oversee integrations, and manage complex data models
Lead Salesforce Developer Contract (Outside IR35) Fully Remote - Day Rate: Competitive, open to negotiation - Duration: 6 months+ Working Arrangements: Fully Remote - Interview: 1 Video Call - About the Role - We are seeking an experienced Lead Salesforce Developer for a hands-on leadership role within a fast-growing, innovative financial services environment. You will take ownership of the Salesforce platform, leading a small, talented team and driving technical excellence across the business. What Youll Do * Lead the design, development, and deployment of Salesforce solutions * Collaborate with stakeholders to gather requirements and deliver tailored functionality * Manage and mentor a team of Salesforce professionals (Administrators, Analysts, and Developers) * Ensure data integrity, oversee integrations, and manage complex data models
)
Role: QA Engineer - Location: London - Type: Hybrid / Remote - Salary: TBC - Contract Type: Permanent - Myn is an AI driven marketplace that connects the candidates, clients and recruiters. Myn collaborates with leading employers to offer exclusive, carefully matched permanent positions. Our Recruitment Partners all have extensive industry experience, and work with a select group of niche clients, to deliver the best possible experience to the candidate. We are working with a fast-growing, product-led tech company and we are looking for a QA Engineer whos passionate about catching bugs, improving processes and making sure every release is rock solid. * Design and execute manual and automated test plans across web and mobile platforms * Collaborate with developers, designers, and PMs to ensure quality from ideation to release
Role: QA Engineer - Location: London - Type: Hybrid / Remote - Salary: TBC - Contract Type: Permanent - Myn is an AI driven marketplace that connects the candidates, clients and recruiters. Myn collaborates with leading employers to offer exclusive, carefully matched permanent positions. Our Recruitment Partners all have extensive industry experience, and work with a select group of niche clients, to deliver the best possible experience to the candidate. We are working with a fast-growing, product-led tech company and we are looking for a QA Engineer whos passionate about catching bugs, improving processes and making sure every release is rock solid. * Design and execute manual and automated test plans across web and mobile platforms * Collaborate with developers, designers, and PMs to ensure quality from ideation to release
Role Full Stack Developer - Location - London (Remote) Salary - £70K - £85K - Role Type Permanent - Myn is an AI driven marketplace that connects the candidates, clients and recruiters. Myn collaborates with leading employers to offer exclusive, carefully matched permanent positions. Overview - Are you a talented Full Stack Developer eager to make an immediate impact on exciting projects? Our client is seeking an experienced Full Stack development professional for a hybrid position to be based in Central London, but operating remotely * Design and implement robust web applications using cutting-edge technologies and frameworks. * Collaborate with cross-functional teams to drive the full development lifecycle, from concept to deployment. * Engage in continuous learning and professional development, enhancing your skills and career prospects.
Role Full Stack Developer - Location - London (Remote) Salary - £70K - £85K - Role Type Permanent - Myn is an AI driven marketplace that connects the candidates, clients and recruiters. Myn collaborates with leading employers to offer exclusive, carefully matched permanent positions. Overview - Are you a talented Full Stack Developer eager to make an immediate impact on exciting projects? Our client is seeking an experienced Full Stack development professional for a hybrid position to be based in Central London, but operating remotely * Design and implement robust web applications using cutting-edge technologies and frameworks. * Collaborate with cross-functional teams to drive the full development lifecycle, from concept to deployment. * Engage in continuous learning and professional development, enhancing your skills and career prospects.
)
Job Title: Site Reliability Engineer - 12 Month Contract - No Sponsorship Available - Job Description - Our client are hiring a Site Reliability Engineering to join their Site Reliability Engineering group whose main objective is to ensure their services are consistently reliable for their customers. As part of adynamicand self-organizing team, you will have the opportunity to work with modern programming languages and manage software within public cloud environments. Our clients cross-functional teams cover the entire technology stack, from front ends to APIs and databases, providing the resources to build, deploy, and operate their own software. Responsibilities * Support applications in production, including responding to incidents and conducting post-incident reviews. * Apply observability engineering to proactively detect system degradation, understand system sta
Job Title: Site Reliability Engineer - 12 Month Contract - No Sponsorship Available - Job Description - Our client are hiring a Site Reliability Engineering to join their Site Reliability Engineering group whose main objective is to ensure their services are consistently reliable for their customers. As part of adynamicand self-organizing team, you will have the opportunity to work with modern programming languages and manage software within public cloud environments. Our clients cross-functional teams cover the entire technology stack, from front ends to APIs and databases, providing the resources to build, deploy, and operate their own software. Responsibilities * Support applications in production, including responding to incidents and conducting post-incident reviews. * Apply observability engineering to proactively detect system degradation, understand system sta
PREMIUM
)
Senior Frontend Engineer (Next.js / React) High-Growth SaaS | Build Elegant, User-First Products - In partnership with Robert Half Limited. We're a high-growth SaaS company scaling fast, and we're looking for a Senior Frontend Engineer to join our team. This is a chance to shape products used by thousands of customers, working with modern tools and a team that values craftsmanship, speed, and impact. Hybrid Working in the City of London, London. 3 days in the office and 2 days from home. What You'll Do * Build and scale complex, high-performing web applications with Next.js and React * Collaborate with design and product to create polished, intuitive, responsive interfaces * Drive improvements in performance, accessibility, and scalability across platforms * Contribute to architecture decisions, code reviews, and design discussions
Senior Frontend Engineer (Next.js / React) High-Growth SaaS | Build Elegant, User-First Products - In partnership with Robert Half Limited. We're a high-growth SaaS company scaling fast, and we're looking for a Senior Frontend Engineer to join our team. This is a chance to shape products used by thousands of customers, working with modern tools and a team that values craftsmanship, speed, and impact. Hybrid Working in the City of London, London. 3 days in the office and 2 days from home. What You'll Do * Build and scale complex, high-performing web applications with Next.js and React * Collaborate with design and product to create polished, intuitive, responsive interfaces * Drive improvements in performance, accessibility, and scalability across platforms * Contribute to architecture decisions, code reviews, and design discussions
Rest API's and Microservice architecture * Restful API Design and development fundamentals * Good SQL knowledge
Rest API's and Microservice architecture * Restful API Design and development fundamentals * Good SQL knowledge
Rest API's and Microservice architecture * Restful API Design and development fundamentals * Good SQL knowledge
Rest API's and Microservice architecture * Restful API Design and development fundamentals * Good SQL knowledge
Applied AI Software Engineer - Python, Fast API, AWS, LLMs - Strong skills with Python & Fast API
Applied AI Software Engineer - Python, Fast API, AWS, LLMs - Strong skills with Python & Fast API
)
Configure and support Axway solutions, including API management and B2B gateway. * Working knowledge of Axway technologies, particularly API management and B2B gateway.
Configure and support Axway solutions, including API management and B2B gateway. * Working knowledge of Axway technologies, particularly API management and B2B gateway.
NEWFEATURED
)
REST API development
REST API development
NEW
Senior Security Engineer Defender PurView Sentinel
Senior Security Engineer Defender PurView Sentinel
Invitise Ltd
EC1A, City of London
Up to £500 per day Outside IR35
PowerShell scripting and use of Microsoft Graph API
PowerShell scripting and use of Microsoft Graph API
NEW
)
Background in API design and automated testing frameworks.
Background in API design and automated testing frameworks.
Hands-on experience integrating external data sources into internal systems using ETL pipelines and API-driven data exchange.
Hands-on experience integrating external data sources into internal systems using ETL pipelines and API-driven data exchange.
NEW
Experience of deploying into and using AWS services including VPC, EC2, RDS, API Gateway
Experience of deploying into and using AWS services including VPC, EC2, RDS, API Gateway
NEW
)
Junior Test Automation Engineer
Junior Test Automation Engineer
Lynx Recruitment Limited
SW1W, South West London
From £35,000 to £50,000 per annum
Hands-on experience with API testing tools such as RestAssured or SoapUI
Hands-on experience with API testing tools such as RestAssured or SoapUI
NEW
Test Automation Engineer
Test Automation Engineer
Lynx Recruitment Limited
SW1W, South West London
From £50,000 to £65,000 per annum
Hands-on experience with API testing tools such as RestAssured or SoapUI
Hands-on experience with API testing tools such as RestAssured or SoapUI
NEW
)
SharePoint REST API: Integration with SharePoint lists and libraries
SharePoint REST API: Integration with SharePoint lists and libraries
)
Proficiency in API testing (Postman or equivalent) and SQL for data validation.
Proficiency in API testing (Postman or equivalent) and SQL for data validation.
NEWFEATURED