Date posted
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Locations
Locations
Salaries
Date posted
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42 API jobs in Hertfordshire + 20 miles
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skilled with API development, message buses and languages such as C#, Python, or PHP
skilled with API development, message buses and languages such as C#, Python, or PHP
FEATURED
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Integration Architect
Integration Architect
Lynx Recruitment Limited
SW1W, South West London
From £85,000 to £100,000 per annum
Create high-level architectural assets, including API catalogues, application and connectivity models, guiding detailed design - Solid understanding of SOA, REST, and API management principles - Proficient with XSD, XML, XSLT, JSON, API
Create high-level architectural assets, including API catalogues, application and connectivity models, guiding detailed design - Solid understanding of SOA, REST, and API management principles - Proficient with XSD, XML, XSLT, JSON, API
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Solid background in Apex, LWC, SOQL, and REST/SOAP API integration.
Solid background in Apex, LWC, SOQL, and REST/SOAP API integration.
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Entity Framework, Blazor (server side), .NET API, Redis Cache
Entity Framework, Blazor (server side), .NET API, Redis Cache
Champion best practices across testing disciplines including unit, integration, UI, API, and performance * Knowledge of web, mobile, API/microservices testing and contract testing (e.g. PACT)
Champion best practices across testing disciplines including unit, integration, UI, API, and performance * Knowledge of web, mobile, API/microservices testing and contract testing (e.g. PACT)
PREMIUM
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Lead Java SDET
Lead Java SDET
Deerfoot Recruitment Solutions
The City, EC4N 6JD
£90000 - £120000 per annum + Benefits + Bonus + Hybrid Working
Lead SDET | SDET | Software Development Engineer in Test | Test Manager | Test Lead | Lead Test Engineer | Principal Test Engineer | QA Lead | Quality Assurance Lead | Software Test Lead | Automation Lead | Java | Unit Testing | Contract Testing | REST | API | Java OOP | API Testing | Cucumber | Selenium WebDriver | JSON | Performance Testing | Leadership
Lead SDET | SDET | Software Development Engineer in Test | Test Manager | Test Lead | Lead Test Engineer | Principal Test Engineer | QA Lead | Quality Assurance Lead | Software Test Lead | Automation Lead | Java | Unit Testing | Contract Testing | REST | API | Java OOP | API Testing | Cucumber | Selenium WebDriver | JSON | Performance Testing | Leadership
FEATURED
Senior Software Developer
Senior Software Developer
Tech 4
E10, East London
From £64,000 to £70,000 per annum + excellent benefits
Assist with the design, implementation, and testing of APIs that adhere to the Open API specification
Assist with the design, implementation, and testing of APIs that adhere to the Open API specification
Hands-on experience with Azure Integration Services: Logic Apps, API Management, Service Bus, Event Grid, Function Apps
Hands-on experience with Azure Integration Services: Logic Apps, API Management, Service Bus, Event Grid, Function Apps
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Cybersecurity Engineer - Hybrid Remote
Cybersecurity Engineer - Hybrid Remote
VERTECH GROUP (UK) LTD
N7, North London
From £65,000 to £75,000 per annum + Benefits
Strong knowledge of web/mobile security (OWASP Top 10, API security), cloud security (AWS), and CI/CD pipeline hardening
Strong knowledge of web/mobile security (OWASP Top 10, API security), cloud security (AWS), and CI/CD pipeline hardening
FEATURED
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At least 2+ years experience with building secure Web Applications utilising an API backend
At least 2+ years experience with building secure Web Applications utilising an API backend
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Experience with API integrations and version control (GitHub/Bitbucket)
Experience with API integrations and version control (GitHub/Bitbucket)
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Senior/Lead Full Stack Developer (React / Python) AI Start up!
Senior/Lead Full Stack Developer (React / Python) AI Start up!
Robert Half
EC1, City of London
Negotiable
API & database experience
API & database experience
API & database experience
API & database experience
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)
NEW
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Senior Node.js Developer
Senior Node.js Developer
ARC IT Recruitment Ltd
SW1V, South West London, SW1W 9SJ
Up to £100,000 per annum
Build and implement new API systems integrating with ferry operators, third-party service providers, and more.
Build and implement new API systems integrating with ferry operators, third-party service providers, and more.
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Senior Data Engineer
Senior Data Engineer
I3 Resourcing Limited
The City, EC3V 3ND
£70000 - £80000 per annum + + EXCELLENT BONUS + BENEFITS
Extensive experience in AWS services, e.g. EC2, S3, RDS, DynamoDB, Redshift, Lambda, API Gateway
Extensive experience in AWS services, e.g. EC2, S3, RDS, DynamoDB, Redshift, Lambda, API Gateway
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Azure Security Engineer - Sentinel, Defender, Purview
Azure Security Engineer - Sentinel, Defender, Purview
Apsley Recruitment Ltd
EC2, City of London
From £60,000 to £68,000 per annum Full benefits package
Hands-on with PowerShell and Microsoft Graph API for security automation
Hands-on with PowerShell and Microsoft Graph API for security automation
Implement and maintain API integrations
Implement and maintain API integrations
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Senior Software Developer
Senior Software Developer
Lean People Services Limited
Luton, Bedfordshire
From £75,000 to £85,000 per annum
up to £85,000 per annum - Full Time Mon-Fri - Our Client provide remote diagnostic solutions and services to the automotive industry. They offer cutting-edge, expert diagnostics using both after-market and original equipment manufacturer tools to provide safe and accurate repairs. The company was founded in 2010 and is headquartered in Plano, TX with UK offices in Peterlee and Bedfordshire. As more automotive software technologies emerge, including autonomous driving, advanced diagnostics, vehicle connectivity, digital cockpits the Company aims to gain a first-mover advantage by developing software solutions with the help of automotive software engineers. If the idea of making an impact on a project lifecycle sounds appealing from its inception down to testing and deployment appeals to you, keep on reading!
up to £85,000 per annum - Full Time Mon-Fri - Our Client provide remote diagnostic solutions and services to the automotive industry. They offer cutting-edge, expert diagnostics using both after-market and original equipment manufacturer tools to provide safe and accurate repairs. The company was founded in 2010 and is headquartered in Plano, TX with UK offices in Peterlee and Bedfordshire. As more automotive software technologies emerge, including autonomous driving, advanced diagnostics, vehicle connectivity, digital cockpits the Company aims to gain a first-mover advantage by developing software solutions with the help of automotive software engineers. If the idea of making an impact on a project lifecycle sounds appealing from its inception down to testing and deployment appeals to you, keep on reading!
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Full Stack Engineer, GraphQL APIs, TypeScript, Node
Full Stack Engineer, GraphQL APIs, TypeScript, Node
Staffworx Limited
Brentford End, TW7
market rates, outside IR35, 6 months initial, 2 days week on site
Full Stack Software Engineer GraphQL | TypeScript | Cloud-Native - Based West London, Hybrid working, 1-2 days week on site. Outside IR35. 6 months initial, likely extensions. Were looking for aFull Stack Software Engineerwho loves building high-quality, scalable systems and isn't afraid to get deep into both the code and the infrastructure. If GraphQL APIs, TypeScript/Node.js backends and cloud-native deployments make you feel right at home, this is your stage. What you ll be doing * Design & buildrobust, scalableTypeScript/Node.jsservices andGraphQL APIsthat power real-world applications. * Write code that lastsclean, maintainable, well-tested, and resilient. * Shape our infrastructurethrough modern DevOps practices: CI/CD pipelines (Jenkins, Concourse), containerisation, Helm, and Kubernetes deployments.
Full Stack Software Engineer GraphQL | TypeScript | Cloud-Native - Based West London, Hybrid working, 1-2 days week on site. Outside IR35. 6 months initial, likely extensions. Were looking for aFull Stack Software Engineerwho loves building high-quality, scalable systems and isn't afraid to get deep into both the code and the infrastructure. If GraphQL APIs, TypeScript/Node.js backends and cloud-native deployments make you feel right at home, this is your stage. What you ll be doing * Design & buildrobust, scalableTypeScript/Node.jsservices andGraphQL APIsthat power real-world applications. * Write code that lastsclean, maintainable, well-tested, and resilient. * Shape our infrastructurethrough modern DevOps practices: CI/CD pipelines (Jenkins, Concourse), containerisation, Helm, and Kubernetes deployments.
Senior Penetration Tester
Senior Penetration Tester
4SQUARE RECRUITMENT LTD
Bermondsey, SE1 3RT
From £50,000 to £75,000 per annum
Location:Fully Remote (UK-Based) Salary Range:£50,000 - £75,000 (dependent on experience) Position:Permanent, Full-Time - My client is a dynamic and growing cybersecurity consultancy dedicated to providing top-tier security services to a diverse range of clients. They believe in empowering the team with the flexibility of remote work while tackling challenging and engaging projects that make a real difference to their clients' security posture. The Role - We are seeking a highly skilled and motivated Senior Penetration Tester to join our remote team. You will be responsible for leading and executing complex penetration tests against a variety of systems, networks, and applications. The ideal candidate is not just a proficient tester but a critical thinker who can articulate risks clearly and provide pragmatic remediation advice to clients. Key Responsibilities
Location:Fully Remote (UK-Based) Salary Range:£50,000 - £75,000 (dependent on experience) Position:Permanent, Full-Time - My client is a dynamic and growing cybersecurity consultancy dedicated to providing top-tier security services to a diverse range of clients. They believe in empowering the team with the flexibility of remote work while tackling challenging and engaging projects that make a real difference to their clients' security posture. The Role - We are seeking a highly skilled and motivated Senior Penetration Tester to join our remote team. You will be responsible for leading and executing complex penetration tests against a variety of systems, networks, and applications. The ideal candidate is not just a proficient tester but a critical thinker who can articulate risks clearly and provide pragmatic remediation advice to clients. Key Responsibilities
NEW
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AI/ LLM - Python React Engineer - Contract Opportunity - London Hybrid based - 70% Python - 30% React - Job Description - We are seeking a highly skilled Python Fullstack Engineer with extensive experience in both front-end and back-end development. This role is very interesting as you will also be working with LLM's and AI/ML. * Knowledge of LangChain or Haystack or Llamalndex - Essential Skills * 10+ years of experience in designing and developing operational support systems and automation solutions using Python. * Front-end development skills, including designing and implementing user interfaces using JavaScript and frameworks such as React. * Back-end development skills, including maintaining server-side logic using Python, managing APIs, and integrating third-party services. * Experience with database management using Postgres to ensure application data integrity
AI/ LLM - Python React Engineer - Contract Opportunity - London Hybrid based - 70% Python - 30% React - Job Description - We are seeking a highly skilled Python Fullstack Engineer with extensive experience in both front-end and back-end development. This role is very interesting as you will also be working with LLM's and AI/ML. * Knowledge of LangChain or Haystack or Llamalndex - Essential Skills * 10+ years of experience in designing and developing operational support systems and automation solutions using Python. * Front-end development skills, including designing and implementing user interfaces using JavaScript and frameworks such as React. * Back-end development skills, including maintaining server-side logic using Python, managing APIs, and integrating third-party services. * Experience with database management using Postgres to ensure application data integrity
NEWPREMIUM
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Mid-Level C++ Developer (5+ years of experience) Location:Hybrid - 2-3 days onsite in Hounslow - Rate:£430 per day (Inside IR35) Duration:12 months (Extension highly likely) Are you an experienced C++ Developer looking for your next long-term contract? We are seeking a technically strong and versatileMid-Level C++ Developerto join our client's high-performing team on a travel technology project. Key Responsibilities * Develop and maintain high-performance Back End components using C++11 or newer. * Design dynamic, responsive Front End interfaces with AngularJS/Angular 2+. * Support and enhance existing systems with a focus on performance, stability, and maintainability. * Collaborate with cross-functional teams (Product Owners, QA, DevOps, etc.) to deliver new features. * Refactor Legacy code and actively contribute to reducing technical debt.
Mid-Level C++ Developer (5+ years of experience) Location:Hybrid - 2-3 days onsite in Hounslow - Rate:£430 per day (Inside IR35) Duration:12 months (Extension highly likely) Are you an experienced C++ Developer looking for your next long-term contract? We are seeking a technically strong and versatileMid-Level C++ Developerto join our client's high-performing team on a travel technology project. Key Responsibilities * Develop and maintain high-performance Back End components using C++11 or newer. * Design dynamic, responsive Front End interfaces with AngularJS/Angular 2+. * Support and enhance existing systems with a focus on performance, stability, and maintainability. * Collaborate with cross-functional teams (Product Owners, QA, DevOps, etc.) to deliver new features. * Refactor Legacy code and actively contribute to reducing technical debt.
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Data Engineer (Defence)
Data Engineer (Defence)
Anson Mccade
SG1, Stevenage
GBP 45,000.00 - 55,000.00 per year;GBP 45,000.00 per year;GBP 55,000.0
£45,000 - 55,000 GBP - Onsite WORKING - Location: Stevenage, Cambridge, East of England - United Kingdom Type: Permanent - Data Engineer - Generative AI | Defence Technology - A leading international defence organisation is seeking an experienced Data Engineer with a focus on Generative AI to join their IM GenAI Delivery Office in the UK. You will play a pivotal role in designing, managing, and optimising datasets that support advanced defence systems and critical internal projects. * Develop and maintain robust, secure, and high-integrity datasets for internal defence applications. * Design and optimise data pipelines to ensure reliable, compliant, and scalable solutions. * Apply your expertise in Generative AI, NLP, and OCR to enhance and automate data processes. * Build ETL workflows, APIs, and other data integration solutions tailored for mission-critical environm
£45,000 - 55,000 GBP - Onsite WORKING - Location: Stevenage, Cambridge, East of England - United Kingdom Type: Permanent - Data Engineer - Generative AI | Defence Technology - A leading international defence organisation is seeking an experienced Data Engineer with a focus on Generative AI to join their IM GenAI Delivery Office in the UK. You will play a pivotal role in designing, managing, and optimising datasets that support advanced defence systems and critical internal projects. * Develop and maintain robust, secure, and high-integrity datasets for internal defence applications. * Design and optimise data pipelines to ensure reliable, compliant, and scalable solutions. * Apply your expertise in Generative AI, NLP, and OCR to enhance and automate data processes. * Build ETL workflows, APIs, and other data integration solutions tailored for mission-critical environm
PREMIUM
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Are you passionate about turning great design into seamless user experiences? Do you thrive on building interfaces that are as functional as they are beautiful? Our client is looking for aFront-End Developerwho loves working at the intersection of design, technology, and usability. What Youll Do * Build responsive, accessible, and high-quality interfaces with modern frameworks (React, Vue, or Angular). * Bring UX best practices to life, ensuring every interaction feels natural and intuitive. * Contribute to design systems and component libraries that scale across products. * Partner with product managers, designers, and backend engineers to deliver delightful experiences. * Stay ahead of front-end trends, accessibility standards, and UX/UI innovations. What they're Looking For * 4+ yearsof experience in front-end development.
Are you passionate about turning great design into seamless user experiences? Do you thrive on building interfaces that are as functional as they are beautiful? Our client is looking for aFront-End Developerwho loves working at the intersection of design, technology, and usability. What Youll Do * Build responsive, accessible, and high-quality interfaces with modern frameworks (React, Vue, or Angular). * Bring UX best practices to life, ensuring every interaction feels natural and intuitive. * Contribute to design systems and component libraries that scale across products. * Partner with product managers, designers, and backend engineers to deliver delightful experiences. * Stay ahead of front-end trends, accessibility standards, and UX/UI innovations. What they're Looking For * 4+ yearsof experience in front-end development.