Date posted
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Locations
Locations
Salaries
Date posted
Type of Company
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93 Contract API jobs in Holborn, Central London + 20 miles
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Senior Full Stack Developer JavaScript Python API
Senior Full Stack Developer JavaScript Python API
Client Server
W6, West London
£85000 - £100000 per annum
Senior Full Stack Developer / Engineer (JavaScript Python API) London to £100k - Apply now to find out more about this Senior Full Stack Developer / Engineer (JavaScript Python API) opportunity.
Senior Full Stack Developer / Engineer (JavaScript Python API) London to £100k - Apply now to find out more about this Senior Full Stack Developer / Engineer (JavaScript Python API) opportunity.
NEWPREMIUM
Fidessa Developer Java - Capital Markets
Fidessa Developer Java - Capital Markets
Client Server
The City, EC3
£100000 - £135000 per annum + bonus + benefits
Fidessa Developer (Java Spring Boot API) London to £135k - As a Fidessa Developer (Java Spring Boot API) you will receive a competitive - Apply now to find out more about this Fidessa Developer (Java Spring Boot API) opportunity.
Fidessa Developer (Java Spring Boot API) London to £135k - As a Fidessa Developer (Java Spring Boot API) you will receive a competitive - Apply now to find out more about this Fidessa Developer (Java Spring Boot API) opportunity.
NEWPREMIUM
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On Monday morning, you might be refining an API connection between a collections database and a public-facing platform. You’ll work on varied and meaningful projects; from API-driven integrations to AI experimentation - helping to shape a modern, secure, and scalable technology environment. If you’ve worked in backend development, software engineering, or API management — and you’re confident with modern PHP and Linux — we’d love to hear from you.
On Monday morning, you might be refining an API connection between a collections database and a public-facing platform. You’ll work on varied and meaningful projects; from API-driven integrations to AI experimentation - helping to shape a modern, secure, and scalable technology environment. If you’ve worked in backend development, software engineering, or API management — and you’re confident with modern PHP and Linux — we’d love to hear from you.
NEWPREMIUM
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On Monday morning, you might be refining an API connection between a collections database and a public-facing platform. You’ll work on varied and meaningful projects; from API-driven integrations to AI experimentation - helping to shape a modern, secure, and scalable technology environment. If you’ve worked in backend development, software engineering, or API management — and you’re confident with modern PHP and Linux — we’d love to hear from you.
On Monday morning, you might be refining an API connection between a collections database and a public-facing platform. You’ll work on varied and meaningful projects; from API-driven integrations to AI experimentation - helping to shape a modern, secure, and scalable technology environment. If you’ve worked in backend development, software engineering, or API management — and you’re confident with modern PHP and Linux — we’d love to hear from you.
NEWFEATURED
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AMS is a global workforce solutions partner committed to creating inclusive, dynamic, and future-ready workplaces. We help organisations adapt, grow, and thrive in an ever-evolving world by building, shaping, and optimising diverse talent strategies. Our Contingent Workforce Solutions (CWS) is one of our service offerings. Acting as an extension of their recruitment teams, we connect them with skilled interim and temporary professionals, fostering workplaces where everyone can contribute and succeed. Our client, a major UK retail bank, provides every day banking services to over 17 million retail customers. The banks expertise and services span across Business Services, Corporate banking, Wealth Management, Group Functions, Retail and Investment Banking. On behalf of this organisation, AMS are looking for 3 - Full Stack Developers for acontract until end of 2025 based
AMS is a global workforce solutions partner committed to creating inclusive, dynamic, and future-ready workplaces. We help organisations adapt, grow, and thrive in an ever-evolving world by building, shaping, and optimising diverse talent strategies. Our Contingent Workforce Solutions (CWS) is one of our service offerings. Acting as an extension of their recruitment teams, we connect them with skilled interim and temporary professionals, fostering workplaces where everyone can contribute and succeed. Our client, a major UK retail bank, provides every day banking services to over 17 million retail customers. The banks expertise and services span across Business Services, Corporate banking, Wealth Management, Group Functions, Retail and Investment Banking. On behalf of this organisation, AMS are looking for 3 - Full Stack Developers for acontract until end of 2025 based
NEWFEATURED
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API Architecture & Security: Design and secure APIs with AWS API Gateway, applying mTLS, certificate-based authentication, and Azure AD integration. Advanced knowledge of AWS services including API Gateway, CloudFront, WAF, VPC, Lambda, EKS, Fargate, and S3. Expertise in API security (mTLS, certificate-based authentication, Azure AD integration).
API Architecture & Security: Design and secure APIs with AWS API Gateway, applying mTLS, certificate-based authentication, and Azure AD integration. Advanced knowledge of AWS services including API Gateway, CloudFront, WAF, VPC, Lambda, EKS, Fargate, and S3. Expertise in API security (mTLS, certificate-based authentication, Azure AD integration).
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AI Solution Architect (AI Agents, Retail / eCommerce)
AI Solution Architect (AI Agents, Retail / eCommerce)
Staffworx Limited
WC1A, Central London
market rates, outside IR35 or permanent
Utilize AWS services (Lambda, S3, API Gateway, SageMaker, DynamoDB, ECS, etc.) to deploy scalable AI solutions. * Experience with AI/ML frameworks such as TensorFlow, PyTorch, OpenAI API, or LangChain. * Strong understanding of API design, including REST, GraphQL, and WebSockets.
Utilize AWS services (Lambda, S3, API Gateway, SageMaker, DynamoDB, ECS, etc.) to deploy scalable AI solutions. * Experience with AI/ML frameworks such as TensorFlow, PyTorch, OpenAI API, or LangChain. * Strong understanding of API design, including REST, GraphQL, and WebSockets.
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API Integration
API Integration
NEWFEATURED
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Strong knowledge of system architecture, cloud solutions, and API design
Strong knowledge of system architecture, cloud solutions, and API design
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Undertake development of customising Dataverse, canvas apps, API integrations with 3rd party systems.
Undertake development of customising Dataverse, canvas apps, API integrations with 3rd party systems.
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7+ years of hands-on coding in server side Java with strong emphasis on Concurrency, Collections API, Messaging and Event processing across multiple streams * Coding with FIX protocol, ION API is a strong plus
7+ years of hands-on coding in server side Java with strong emphasis on Concurrency, Collections API, Messaging and Event processing across multiple streams * Coding with FIX protocol, ION API is a strong plus
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7+ years of hands-on coding in server side Java with strong emphasis on Concurrency, Collections API, Messaging and Event processing across multiple streams * Coding with FIX protocol, ION API is a strong plus
7+ years of hands-on coding in server side Java with strong emphasis on Concurrency, Collections API, Messaging and Event processing across multiple streams * Coding with FIX protocol, ION API is a strong plus
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Back End Integration Engineer
Back End Integration Engineer
I3 Resourcing Limited
The City, EC3V 3ND
£70000 - £80000 per annum + + BENS + BONUS
Strong experience in application and integration design, including microservices architecture and API lifecycle management. o API Management, Service Bus, Logic Apps, Azure Functions
Strong experience in application and integration design, including microservices architecture and API lifecycle management. o API Management, Service Bus, Logic Apps, Azure Functions
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Contract / Outside IR35 - A leading UK-based organisation is undergoing a strategic transformation of its enterprise systems, with Workday at the core of its HR and finance operations. We're seeking a Lead Integration Architect to design and oversee the integration landscape, ensuring seamless data flows across platforms using Workato. Key Responsibilities * Define and lead integration architecture across Workday and other enterprise platforms * Develop scalable, reusable integration patterns using Workato and other middleware tools * Ensure alignment with enterprise architecture principles and IT governance * Collaborate with Workday implementation teams to ensure integration readiness * Design and implement data flows between Workday and legacy systems * Support data migration, validation, and reconciliation * Own Workato platform governance, performance, and roadma
Contract / Outside IR35 - A leading UK-based organisation is undergoing a strategic transformation of its enterprise systems, with Workday at the core of its HR and finance operations. We're seeking a Lead Integration Architect to design and oversee the integration landscape, ensuring seamless data flows across platforms using Workato. Key Responsibilities * Define and lead integration architecture across Workday and other enterprise platforms * Develop scalable, reusable integration patterns using Workato and other middleware tools * Ensure alignment with enterprise architecture principles and IT governance * Collaborate with Workday implementation teams to ensure integration readiness * Design and implement data flows between Workday and legacy systems * Support data migration, validation, and reconciliation * Own Workato platform governance, performance, and roadma
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Strong knowledge of GraphQL (API design, schema evolution, integration).
Strong knowledge of GraphQL (API design, schema evolution, integration).
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Ensuring feature parity and API alignment between different platforms
Ensuring feature parity and API alignment between different platforms
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Familiarity with tools for working with Large Language Models via API or in a local context (e.g. HuggingFace transformers).
Familiarity with tools for working with Large Language Models via API or in a local context (e.g. HuggingFace transformers).
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Build and maintain API-based interfaces, ensuring security and compliance with industry standards.
Build and maintain API-based interfaces, ensuring security and compliance with industry standards.
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Manage API integrations between platforms. * Strong capability with API integrations and low/no-code tools (n8n, Zapier, Airtable, Make).
Manage API integrations between platforms. * Strong capability with API integrations and low/no-code tools (n8n, Zapier, Airtable, Make).
FEATURED
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Anypoint API Manager
Anypoint API Manager
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Senior Software Engineer
Senior Software Engineer
Halian Technology Limited
W1, Central London
From £90,000 to £95,000 per annum Plus bonus and benefits
Cloud experience withAWSservices (Lambda, API Gateway, S3, etc.)
Cloud experience withAWSservices (Lambda, API Gateway, S3, etc.)
NEW
Collaborate with Data Analysts, Architects, and system owners to improve data quality and support API/Middleware-based data management. * Full lifecycle development experience on the Mulesoft Anypoint Platform (Design Centre, Exchange, Studio, API Manager, Runtime Manager). * Proficiency in RESTful API development and working with XML, XSLT, and XSD.
Collaborate with Data Analysts, Architects, and system owners to improve data quality and support API/Middleware-based data management. * Full lifecycle development experience on the Mulesoft Anypoint Platform (Design Centre, Exchange, Studio, API Manager, Runtime Manager). * Proficiency in RESTful API development and working with XML, XSLT, and XSD.
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ASP.NET Web API
ASP.NET Web API
NEW
Perform Dataverse customizations, SQL queries, and CRUD operations using REST/Web API calls. * JavaScript (customizations & API calls)
Perform Dataverse customizations, SQL queries, and CRUD operations using REST/Web API calls. * JavaScript (customizations & API calls)
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Python, Flask ,Azure, MySQL, API, Django, FastAPI
Python, Flask ,Azure, MySQL, API, Django, FastAPI
NEWFEATURED