Date posted
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Locations
Type of Company
Job types
Salaries
Locations
92 API jobs in Hertfordshire + 20 miles
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Fidessa Developer Java API OMS - Capital Markets
Fidessa Developer Java API OMS - 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
A top-tier defense organization is looking for an experienced Axway API Developer / Administrator to join their team on a 6-month contract. * Axway's core products: Policy Studio, API Gateway, and API Manager. If you are an experienced professional with a background in API, MFT, or secure file transfers, this could be the perfect opportunity for you.
A top-tier defense organization is looking for an experienced Axway API Developer / Administrator to join their team on a 6-month contract. * Axway's core products: Policy Studio, API Gateway, and API Manager. If you are an experienced professional with a background in API, MFT, or secure file transfers, this could be the perfect opportunity for you.
NEWFEATURED
As a C++ Developer you will focus on enabling the core product, written in C / C++ for Windows and Linux to run on Apple Mac software, using the latest Extensions, tools and API integrations.
As a C++ Developer you will focus on enabling the core product, written in C / C++ for Windows and Linux to run on Apple Mac software, using the latest Extensions, tools and API integrations.
NEWPREMIUM
Backend Software Engineer Java Kotlin AWS
Backend Software Engineer Java Kotlin AWS
Client Server
Shoreditch, EC2A 2AP
£100000 - £120000 per annum
Backend Software Engineer / Developer (Java Kotlin AWS API) Hybrid WFH to £110k
Backend Software Engineer / Developer (Java Kotlin AWS API) Hybrid WFH to £110k
NEWPREMIUM
API Integration
API Integration
NEWFEATURED
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Strong background in microservices architecture, including both front-end (UI) and API components.
Strong background in microservices architecture, including both front-end (UI) and API components.
NEW
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Experience with API development and Git.
Experience with API development and Git.
Build scalable cloud solutions using Azure PaaS services (App Services, Function Apps, API Management, etc.)
Build scalable cloud solutions using Azure PaaS services (App Services, Function Apps, API Management, etc.)
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Strong scripting and integration skills - JavaScript, SQL, API/Web Services.
Strong scripting and integration skills - JavaScript, SQL, API/Web Services.
PREMIUM
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Skills: C#.Net, XML / JSON API's, SC & NPPV3 Clearance
Skills: C#.Net, XML / JSON API's, SC & NPPV3 Clearance
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Proficiency in Microsoft Graph API, Azure OpenAI, and Semantic Kernel
Proficiency in Microsoft Graph API, Azure OpenAI, and Semantic Kernel
NEW
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Strong grasp of databases (SQL/NoSQL) and API integrations
Strong grasp of databases (SQL/NoSQL) and API integrations
NEW
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Applications Support Analyst/Developer
Applications Support Analyst/Developer
Kudos Partners
Datchet Common, SL3
£75,000 per annum plus 12% bonus - generous benefits package
API support and monitoring tools (e.g., SolarWinds, AzureAppInsights)
API support and monitoring tools (e.g., SolarWinds, AzureAppInsights)
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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
Microsoft Graph API understanding for advanced integrations * Experience with SharePoint REST API and modern development practices
Microsoft Graph API understanding for advanced integrations * Experience with SharePoint REST API and modern development practices
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Monitor and incorporate changes to QA compliance incorporating relevant design codes (ASME, API, etc.)
Monitor and incorporate changes to QA compliance incorporating relevant design codes (ASME, API, etc.)
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Microsoft Power Platform / Agentic AI Engineer
Microsoft Power Platform / Agentic AI Engineer
cer Financial
EC2M, City of London
£705 per day £705 per day (via Umbrella)
Microsoft 365 & Graph API Integration * Proficiency in Microsoft Graph API, Azure OpenAI, and Semantic Kernel
Microsoft 365 & Graph API Integration * Proficiency in Microsoft Graph API, Azure OpenAI, and Semantic Kernel
FEATURED
.NET Developer
.NET Developer
Halian Technology Limited
W1, Central London
From £70,000 to £80,000 per annum Plus bonus and benefits
Proven hands-on experience withAWS servicessuch as Lambda, ECS/Fargate, API Gateway, DynamoDB, S3, CloudFormation/Terraform.
Proven hands-on experience withAWS servicessuch as Lambda, ECS/Fargate, API Gateway, DynamoDB, S3, CloudFormation/Terraform.
NEW
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Forward Deployed Engineer
Forward Deployed Engineer
McGregor Boyall Associates Limited
EC1, City of London
£70000 - £90000 per annum
Strong data modelling, pipeline development, and API design experience.
Strong data modelling, pipeline development, and API design experience.
NEW
Strong background in software architecture, microservices, and API design.
Strong background in software architecture, microservices, and API design.
NEW
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Experience with Python for data extraction and API integration.
Experience with Python for data extraction and API integration.
FEATURED
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Ideal candidates will have a good background in Java and Python, along with a strong understanding of APIs (REST API, XML). * Api
Ideal candidates will have a good background in Java and Python, along with a strong understanding of APIs (REST API, XML). * Api
PREMIUM
Senior Solution Architect
Senior Solution Architect
UK Health Security Agency
Canary Wharf, E14 4PU
From £54,416 to £68,344 per annum
The United Kingdom Health Security Agency (UKHSA) is a system leader for health security; taking action internationally to strengthen global health security, providing trusted advice to government and the public and reducing inequalities in the way different communities experience and are impacted by infectious disease, environmental hazards, and other threats to health. UKHSAs remit, as an agency with a global-to-local reach, is to protect the health of the nation from infectious diseases and other external threats to health. * Prevent: anticipate threats to health and help build the nations readiness, defences and health security * Detect: use cutting edge environmental and biological surveillance to proactively detect and monitor infectious diseases and threats to health * Analyse: use world-class science and data analytics to assess and continually monitor threats
The United Kingdom Health Security Agency (UKHSA) is a system leader for health security; taking action internationally to strengthen global health security, providing trusted advice to government and the public and reducing inequalities in the way different communities experience and are impacted by infectious disease, environmental hazards, and other threats to health. UKHSAs remit, as an agency with a global-to-local reach, is to protect the health of the nation from infectious diseases and other external threats to health. * Prevent: anticipate threats to health and help build the nations readiness, defences and health security * Detect: use cutting edge environmental and biological surveillance to proactively detect and monitor infectious diseases and threats to health * Analyse: use world-class science and data analytics to assess and continually monitor threats
NEW
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Lead .Net Software Developer
Lead .Net Software Developer
Hireful
Milton Keynes, Buckinghamshire
£65k - £75k base salary plus Bonus and awesome benefits
Are you a hands-on Lead or Senior .Net Developer ready to shape architecture and guide talented developers? Want a hybrid role with 3 days WFH? This is your chance to stay close to the code while making key technical decisions that drive real business impact. You'll join a collaborative, forward-thinking team building cutting-edge products — with the support, tools, and flexibility to thrive. Role: Lead Software Developer, Senior .Net Developer, Software Engineering Manager, Senior Full Stack Developer, Lead .Net Developer, Lead Software Engineer, Senior C# Developer - Salary: £65k - £75k base + Bonus - Benefits: 5% pension, 25 days holiday, 2 wellbeing days, Christmas shutdown, private healthcare, life assurance, cinema tickets & more - Location: Milton Keynes – Hybrid (2 days a week in office) If you’ve got strong .Net (C#) experience and skills in GitHub, APIs, Pos
Are you a hands-on Lead or Senior .Net Developer ready to shape architecture and guide talented developers? Want a hybrid role with 3 days WFH? This is your chance to stay close to the code while making key technical decisions that drive real business impact. You'll join a collaborative, forward-thinking team building cutting-edge products — with the support, tools, and flexibility to thrive. Role: Lead Software Developer, Senior .Net Developer, Software Engineering Manager, Senior Full Stack Developer, Lead .Net Developer, Lead Software Engineer, Senior C# Developer - Salary: £65k - £75k base + Bonus - Benefits: 5% pension, 25 days holiday, 2 wellbeing days, Christmas shutdown, private healthcare, life assurance, cinema tickets & more - Location: Milton Keynes – Hybrid (2 days a week in office) If you’ve got strong .Net (C#) experience and skills in GitHub, APIs, Pos
NEWFEATURED
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Systems Engineer - Enterprise Technology
Systems Engineer - Enterprise Technology
Randstad Digital
EC1, City of London
£250000 - £350000 per annum
Proficiency with the administration, integration, and API capabilities of SaaS platforms such as Okta, Google Workspace, Atlassian products, and Slack. * Familiarity with authentication and provisioning methods like SAML, OIDC, SCIM, and non-standard API-based workflows.
Proficiency with the administration, integration, and API capabilities of SaaS platforms such as Okta, Google Workspace, Atlassian products, and Slack. * Familiarity with authentication and provisioning methods like SAML, OIDC, SCIM, and non-standard API-based workflows.
NEWFEATURED