22 of 22 API Development Jobs in London

Senior Developer

Hiring Organisation
Ascend Consulting
Location
North West London, London, England, United Kingdom
Employment Type
Full-Time
Salary
£45,000 - £80,000 per annum
Senior Developer, Back End, API, .Net SQL, NW London to £80K (office based role) A Senior Back End Developer is required to join this established financial software house based in North London. They work with some of the leading brands in retail and media, offering financial management systems developed … required with expertise in .NET, C#/VB, SQL Server, and SAP Business One integration. The ideal candidate should have strong skills in RESTful API development, database optimization, and Azure DevOps pipeline management. Knowledge of API security, CI/CD automation, and Swagger documentation is recommended. Responsibilities ...

AI Security Engineer

Hiring Organisation
Anson Mccade
Location
City of London, London, United Kingdom
Employment Type
Permanent, Work From Home
tools, scripts, and benchmarks to automate AI/ML security testing Perform secure code reviews and penetration testing of AI-related software Research and Development Research emerging threats, trends, and best practices in AI/ML security Deliver proof-of-concepts and proof-of-value initiatives to assess … technologies and controls Contribute to the development of advanced AI/ML security tools and techniques Produce high-quality technical documentation and user guidance Security Engineering and Collaboration Provide subject matter expertise on security engineering patterns and controls Support secure software development practices aligned to OWASP and DevSecOps ...

Python Full Stack Developer

Hiring Organisation
Syntax Consultancy Ltd
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
£550/day Inside IR35
chance to work with a leading global IT and Digital transformation business specialising in Government projects: Key experience, responsibilities + tasks: Strong Python development expertise , develop and maintain Python code for data processing, API development and integration with the Azure Databricks environment. Senior experience in software development, with a focus on both front-end and back-end development. Front-end development using React, Angular, Vue.js, Front-end and back-end development of applications and APIs interacting with the Azure Databricks platform. Experience with Azure cloud platform and services. Azure Databricks. containerisation (Docker) and orchestration ...

Back End Developer

Hiring Organisation
Omnis Partners
Location
City of London, London, United Kingdom
Implementing CI/CD pipelines (GitHub Actions, GitLab, Jenkins, ArgoCD) • Shipping production-grade cloud-native applications 🎯 What We’re Looking For 👉 Strong Python backend development experience 👉 API development (FastAPI highly desirable) 👉 Solid SQL/PostgreSQL knowledge 👉 AWS experience (EKS ideal) 👉 Kubernetes deployment experience 👉 Terraform (Infrastructure as Code ...

Back End Developer

Hiring Organisation
Omnis Partners
Location
City of London, Greater London, UK
Implementing CI/CD pipelines (GitHub Actions, GitLab, Jenkins, ArgoCD) • Shipping production-grade cloud-native applications 🎯 𝗪𝗵𝗮𝘁 𝗪𝗲’𝗿𝗲 𝗟𝗼𝗼𝗸𝗶𝗻𝗴 𝗙𝗼𝗿 👉 Strong Python backend development experience 👉 API development (FastAPI highly desirable) 👉 Solid SQL/PostgreSQL knowledge 👉 AWS experience (EKS ideal) 👉 Kubernetes deployment experience 👉 Terraform (Infrastructure as Code ...

Senior Python Developer

Hiring Organisation
Experis
Location
City of London, London, United Kingdom
Employment Type
Contract
Contract Rate
£500 - £540 per day
IR35 - Umbrella only About the Role: We are seeking a highly skilled and versatile Senior Developer to join our team and contribute to the development and maintenance of our cutting-edge Azure Databricks platform for economic data. This platform is critical for our Monetary Analysis, Forecasting, and Modelling activities. … Senior Developer will be responsible for both front-end and back-end development, with a focus on Python, including the challenging but rewarding task of reverse engineering an existing codebase to integrate new features and improvements. This role requires a strong understanding of software development principles, experience with ...

Solution Architect

Hiring Organisation
Experis
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
£450 - £506/day
/3 days on site Duration: 04/05/2027 Rate- £506 MUST BE PAYE THROUGH UMBRELLA Key Responsibilities: Lead and manage software development projects using Java, Python, Typescript, AWS, React JS, Angular, and other technologies. Collaborate with cross-functional teams to define project scope, objectives, and deliverables. … data, wherever possible Work with cross-functional teams to deliver the defined scope, objectives, and deliverables on technical grounds Facilitate communication between stakeholders, development teams, and other departments. Ensure adherence to software development lifecycle (SDLC) processes and best practices. Develop detailed project plans, including timelines, resource allocation ...

Python AI Engineer

Hiring Organisation
Crisil
Location
City of London, London, United Kingdom
Engineer with Databricks exposure Overview We are looking for a Python AI Engineer (with Databricks exposure) with hands-on experience in Generative AI, backend development, and database-driven applications. The role involves designing and building AI-enabled applications, developing APIs and services to deploy AI models, and integrating them … with enterprise databases and cloud platforms. The candidate should be comfortable working across AI solution design, backend development, and data engineering. Key Responsibilities • Design and develop AI and Generative AI applications using Python. • Build backend services and APIs using Flask or Django for AI-powered systems. • Work with enterprise ...

Senior Full-Stack Engineer (Node.JS/React/Next.JS)

Hiring Organisation
Ithika Recruitment Ltd
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
£85,000 - £90,000 per annum
Improved performance and reliability of key product areas Helped shape engineering practices around code quality, testing, and maintainability Tech Stack: TypeScript/JavaScript Node.js (API development) React, Next.js AWS Serverless (Lambda, API Gateway) Vercel SQL Server Algolia CI/CD (TeamCity) You Might Be a Good ...

Engineering Manager - Software & ML

Hiring Organisation
Capital One UK
Location
City, London, United Kingdom
Employment Type
Permanent
Salary
GBP Annual
London, London Engineering Manager - Software & ML About this role We are looking for a Software Engineering Manager who brings a solid foundation in modern development and some experience with Machine Learning environments . You'll lead and grow a team that builds the core software powering our data-driven … Collaborate with Product Managers and Data Scientists to ensure ML models are effectively integrated into our production software. Build Robust Systems: Oversee the development of platforms that are performant, secure, and capable of handling the unique deployment needs of AI-powered features. Optimize Delivery: Enhance engineering and agile processes ...

Senior C# Developer C# .Net - Sports Trading

Hiring Organisation
Client Server
Location
City of London, London, United Kingdom
Employment Type
Permanent
team on Greenfield projects which you'll take ownership of and will see the business impact of. There's a focus on backend and API development although you'll also have elements of front end work with JavaScript and React.js. Location: You'll be based in plush City … office on a fulltime basis, Monday to Friday. About you: You have expertise with C# .Net, ASP.Net development You have a strong knowledge of databases (SQL or Oracle) You're comfortable with JavaScript/React You have a thorough knowledge of Computer Science fundamentals such as OOP, Design Patterns ...

Senior AI Engineer (Platform)

Hiring Organisation
Harnham
Location
New Malden, England, United Kingdom
Software Engineering with strong applied AI experience Deep expertise in GCP (Vertex AI, BigQuery, Cloud Run/Functions, ADK, Model Garden) Strong Python and API development experience Hands‐on with LLMs, embeddings, RAG, vector databases Proven track record building production‐ready AI systems with observability and testing Solid ...

Senior AI Engineer

Hiring Organisation
Harnham
Location
London Area, United Kingdom
engineering with clear documentation and stakeholder collaboration. Your Skills and Experience To be successful, you will bring: • Strong Python skills for backend services, SDKs, API development, authentication and testing. • Hands‐on experience working with LLMs, embeddings, prompt engineering, tool calling and RAG design. • Practical knowledge of GCP services ...

Senior Data Scientist - 12 Month FTC

Hiring Organisation
Vitality Corporate Services Limited
Location
Central London, London, United Kingdom
Employment Type
Permanent
Salary
£95,000
leverage external tools Familiarity with agentic SDKs (ADK, LangChain, LlamaIndex, etc.) Proven track record of deploying AI applications into production environments Strong understanding of API development, microservices, and containerization (Docker, Kubernetes) Knowledge of MLOps best practices Excellent problem-solving skills and ability to work in a fast-paced ...

Backend Software Engineer C# .Net SQL - Sports Trading

Hiring Organisation
Client Server
Location
City of London, London, United Kingdom
Employment Type
Permanent
Salary
£90,000
earning substantial bonuses. What's in it for you: Salary to £90k Bonus paid every six months based on personal performance (10-25%) Professional development Pension Health Insurance Gym membership Social events, free fruit, snacks, coffee etc. Your role: As a Backend Software Engineer within the trading engine team … team on Greenfield projects which you'll take ownership of and will see the business impact of. There's a focus on backend and API development although you'll also have elements of front end work with JavaScript and React.js. Location: You'll be based in plush City ...

Software Engineer

Hiring Organisation
Propel
Location
City of London, London, United Kingdom
unlock new revenue streams. 💻 The Role You’ll play a key part in building and scaling a modern fintech platform, working across: Backend: Node.js (API development & scalable services) Frontend: React Native (iOS & Android apps) Database: MongoDB CI/CD, Git, and clean coding best practices You’ll collaborate ...

Java Developer

Hiring Organisation
Sanderson
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
£550 per day
seeking a skilled Java Developer to join our engineering team and contribute to the design, development, and maintenance of high-quality, scalable software solutions. The ideal candidate has strong experience in core Java, modern frameworks, API development, and cloud-based architectures. You will work closely with product ...

GenAI Specialist

Hiring Organisation
Velocity Talent Ltd
Location
Bromley, London, United Kingdom
Employment Type
Contract
Contract Rate
From £500 to £550 per day £500 TO £550 A DAY inside IR35
hybrid 8-12 month contract paying £500 - £550 per day inside IR35, (2-3 days in the office) This includes core Python development using OOPs concepts, Large Language Models (LLMs), and Agentic AI architectures. The ideal candidate will collaborate with clients to understand complex business challenges, architect scalable … Capital Markets. As a Senior Lead Analyst, you will: Anchor the engagement effort from business process consulting and problem definition to solution design, development, and deployment. Lead the discovery and definition of AI/ML solutions and guide teams on project processes and deliverables. Act as a thought leader ...

Full Stack Engineer

Hiring Organisation
Rise Technical
Location
City of London, London, United Kingdom
expanding its internal systems and automation capabilities and is looking for a developer with strong experience in Python, AWS cloud services, and modern API development. This role offers the chance to work on impactful projects including business automation, data processing systems, and modern web applications. In this role … build backend services, APIs, and automation tools. You will work with technologies such as Python, AWS services including Lambda, EC2, S3, RDS, and API Gateway, as well as SQL databases and data processing libraries. You will also contribute to front end development using React where required and support ...

Senior Full Stack Engineer

Hiring Organisation
Access Computer Consulting
Location
City of London, London, United Kingdom
Employment Type
Contract
Contract Rate
£400 - £440/day
Java Full Stack, React, Kubernetes & Docker. Experience in building responsive, component based user interfaces using modern front end frameworks. Hands on expertise in API design and development (REST/JSON), including versioning and backward compatibility. Experience with UI testing, component testing, and front end build tooling. Experience ...

Applications Developer

Hiring Organisation
Ryder Reid Legal Ltd
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
Salary negotiable
aligned with business goals. What They Are Looking For Degree in Computer Science, Information Systems, or related field. Minimum 3 years' experience in software development, with strong skills in SharePoint, SQL Server, and the .NET environment. Proficiency in C#, ASP.NET MVC/Core, and web API development. Experience … with front-end frameworks and modern development practices. Strong problem-solving skills and ability to manage multiple projects. Excellent communication and collaboration skills. Why Apply? This is a fantastic opportunity to join a prestigious global organization that values innovation and offers a collaborative, forward-thinking environment. You'll work ...

Backend Software Engineer Junior-Mid Level - Programmatic

Hiring Organisation
Mobkoi
Location
City of London, London, England, United Kingdom
Employment Type
Full-Time
Salary
Competitive salary
partners developing the best technology across the globe. ROLE OVERVIEW As a Backend Software Engineer (Junior–Mid Level) – Programmatic, you will contribute to the development and evolution of MOBKOI’s programmatic advertising platform. You will work closely with experienced engineers on backend systems that power real-time bidding … exposure to the programmatic advertising ecosystem. You will be supported through mentorship, code reviews, and progressive ownership of backend components. RESPONSIBILITIES • Contribute to the development and improvement of MOBKOI’s programmatic backend systems, including components of the real-time bidding (RTB) pipeline.• Support the design and implementation of scalable ...