20 senior software engineer jobs found in London, greater london

Senior Backend Engineer (TypeScript / GCP) London (2 days hybrid onsite presence), 6 Month Contract, Outside IR35 We’re working with a high-growth fintech platform undergoing a major phase of product expansion. They are looking for Senior Backend Engineers to join an established team and contribute immediately to delivering production ready features across new product lines. This is a hands-on build role, ideal for engineers who are comfortable joining an existing codebase and shipping value from the first few weeks. What You’ll Be Doing Building and delivering end-to-end backend features in a live production environment Writing production-quality code (tested, observable, scalable) Contributing to technical design decisions within your workstream Collaborating closely with engineers via code reviews and shared standards Taking full ownership of services, including debugging and ongoing improvements Tech Stack (Must-Have) TypeScript (Node.js /...

🚀 Principal Engineer (Contract) – Insurtech | £600/day Outside IR35 I’m working with a high-growth Insurtech scale-up looking for a Principal Engineer to lead a major platform modernisation. 💰 Up to £600/day (Outside IR35) 📆 Initial 2-month contract (strong extension potential) ⚡ One-stage interview – moving fast The role: Own and shape architecture for large-scale, cloud-native systems Drive platform modernisation and technical strategy Mentor senior engineers and influence multiple teams Bridge business goals with technical delivery Tech: Golang, modern backend systems AWS (Lambda, DynamoDB) + exposure to Azure Terraform / IaC, containers Bonus: .NET, TypeScript, React This is a high-impact role in a business investing heavily in its next growth phase. 👉 Interviews are happening now – apply ASAP or message me directly to discuss.

Description We are seeking a passionate Software Engineering Manager with a strong background in modern frontend engineering, particularly React, Next.js, and TypeScript, to provide technical leadership and operate with excellence. Creative, curious, and confident, you will be an integral part of our empowered, self-managing, multi-disciplinary engineering teams -designing, building, releasing, and maintaining high-quality digital products. You will play a key role in shaping and growing a best-in-class frontend engineering capability, establishing modern development practices and building scalable, high-performance web applications. This is an initial 6-month contract (outside IR35) requiring 3 days per week onsite in Paddington, London. Key Accountabilities Team Leadership Build, mentor, and lead a high-performing team of frontend engineers specialising in React, Next.js, and TypeScript. Foster a culture of collaboration, technical excellence, and...

Full job description Description We are seeking a passionate  Software Engineering Manager  with a strong background in  modern frontend engineering , particularly  React, Next.js, and TypeScript , to provide technical leadership and operate with excellence. Creative, curious, and confident, you will be an integral part of our empowered, self-managing, multi-disciplinary engineering teams—designing, building, releasing, and maintaining high-quality digital products. You will play a key role in shaping and growing a  best-in-class frontend engineering capability , establishing modern development practices and building scalable, high-performance web applications. This is an  initial 6-month contract (outside IR35)  requiring  3 days per week onsite in Paddington, London . Requirements Key Accountabilities Team Leadership Build, mentor, and lead a high-performing team of  frontend engineers...

Description We are seeking a passionate  Software Engineering Manager  with a strong background in  modern frontend engineering  , particularly  React, Next.js, and TypeScript  , to provide technical leadership and operate with excellence. Creative, curious, and confident, you will be an integral part of our empowered, self-managing, multi-disciplinary engineering teams—designing, building, releasing, and maintaining high-quality digital products. You will play a key role in shaping and growing a  best-in-class frontend engineering capability  , establishing modern development practices and building scalable, high-performance web applications. This is an  initial 6-month contract (outside IR35)  requiring  3 days per week onsite in Paddington, London  . Requirements Key Accountabilities Team Leadership Build, mentor, and lead a high-performing team of  frontend engineers specialising...

Description We are seeking a passionate Software Engineering Manager with a strong background in modern frontend engineering , particularly React, Next.js, and TypeScript , to provide technical leadership and operate with excellence. Creative, curious, and confident, you will be an integral part of our empowered, self-managing, multi-disciplinary engineering teams—designing, building, releasing, and maintaining high-quality digital products. You will play a key role in shaping and growing a best-in-class frontend engineering capability , establishing modern development practices and building scalable, high-performance web applications. This is an initial 6-month contract (outside IR35) requiring 3 days per week onsite in Paddington, London . Requirements Key Accountabilities Team Leadership Build, mentor, and lead a high-performing team of frontend engineers specialising in React, Next.js, and TypeScript. Foster a culture of collaboration, technical...

Description We are seeking a passionate  Software Engineering Manager  with a strong background in  modern frontend engineering , particularly  React, Next.js, and TypeScript , to provide technical leadership and operate with excellence. Creative, curious, and confident, you will be an integral part of our empowered, self-managing, multi-disciplinary engineering teams—designing, building, releasing, and maintaining high-quality digital products. You will play a key role in shaping and growing a  best-in-class frontend engineering capability , establishing modern development practices and building scalable, high-performance web applications. This is an  initial 6-month contract (outside IR35)  requiring  3 days per week onsite in Paddington, London . Requirements Key Accountabilities Team Leadership Build, mentor, and lead a high-performing team of  frontend engineers specialising in React, Next.js, and...

Senior Software Engineer | Java | AI | London | £500- £600/day About the Role We are seeking an exceptional Senior Software Engineer with expertise in Java and AI to join our client, an established financial services brand, on a 6-month contract Outside IR35. This is a unique opportunity for a Senior Software Engineer to work at the cutting edge of AI-driven development. The Opportunity As a Senior Software Engineer, you 'll join a small, innovative team modernising and simplifying critical legacy services using cutting-edge AI tooling. You 'll demonstrate what 's possible when AI is deeply integrated throughout the software development lifecycle, working with the latest AI technologies including Claude Code, GitHub Copilot, MCP, LLMs. Senior Software Engineer will: Develop and maintain software applications using Java Implement AI solutions to enhance software functionality and accelerate development workflows Collaborate with...

Senior Java Engineer – Hedge Fund Contract Outside IR35 £1100 PD 2 month contract Hybrid Quant Capital is urgently looking for a Senior Java Engineer to join our high profile client. Our client is a well known Systematic Trading Hedge Fund. They like technology especially the opensource variety as well as scalability and robust performance (much like their track record). They currently run around £2 billion in liquid capital. The business has expanded continuously and is building a new risk engine for their systematic fund clients. This role will be working with a large distributed system (Built in Java) automating a large volume of realtime data into a portfolio management system. I am looking for a proficient developer with good data knowledge and an understanding of latency. I am looking for an engineer with strong core Java knowledge who is happy to learn risk. You should be happy to expand a data platform from scratch with some serious help on the...

Senior Infrastructure Engineer - Central London £550 - £600 p/d (outside IR35) 3 month initial term A leading construction engineering business is seeking a Senior Infrastructure Engineer to join their team. They are a well-established business about to enter a period of considerable operational change, including merger and acquisition activity, making it an exciting time to join and be part of their journey. Reporting into the Infrastructure Manager, you will oversee core infrastructure and networking. You 'll work closely with managed service providers to ensure seamless operations and business continuity, whilst taking a lead on regular site set-ups and supporting infrastructure integration across newly acquired entities. Key Responsibilities: * Lead and manage office and site networks, aligning with business strategy * Act as an escalation point for the Service Desk Team * Set up and configure Local...

Contract Senior .NET Engineer - £650/day (OUTSIDE IR35) - Hybrid working We are partnering with a rapidly growing, private equity-backed tech company that is delivering cutting-edge tax and regulatory software to an elite client base. With a team of approximately 140 and a strong, collaborative culture, this organisation is known for innovation, reliability, and outstanding customer service They are now seeking an experienced Contract Snr .NET Engineer to work on their enterprise-grade, cloud-native SaaS product helping multinational organisations. Key Responsibilities: Own technical strategy Shape the technology roadmap Guide architecture & refactoring Champion code quality Drive AI augmented What You Bring: Deep expertise in .NET, Cloud & DevOps: Azure App Service, Functions, Azure SQL, Storage, Key Vault, Azure DevOps Pipelines, Bicep / Terraform, CI/CD SPA frameworks (Vue preferred). Extensive enterprise market background Successful...

Senior Infrastructure Engineer - Central London £550 - £600 p/d (outside IR35) 3 month initial term A leading construction engineering business is seeking a Senior Infrastructure Engineer to join their team. They are a well-established business about to enter a period of considerable operational change, including merger and acquisition activity, making it an exciting time to join and be part of their journey. Reporting into the Infrastructure Manager, you will oversee core infrastructure and networking. You'll work closely with managed service providers to ensure seamless operations and business continuity, whilst taking a lead on regular site set-ups and supporting infrastructure integration across newly acquired entities. Key Responsibilities: * Lead and manage office and site networks, aligning with business strategy * Act as an escalation point for the Service Desk Team * Set up and configure Local Area Networks (LANs), including hardware deployment and support *...

Role Type: Contract Title: Senior C# Engineer Client: Established Financial Institution Rate: Up to £600 P/D! Location: London/Hybrid Duration: 6 month rolling My client is a well-established and successful tech house working in the finance sector who are looking a talented senior C# Developer, with outstanding technical and communication skills to join their existing team of software engineers and work on an exciting new project! You will get the chance to work with some of the best technologists out there, one some of the most up to date tech in the industry, on a greenfields project! This is a 6 month rolling Contract, with high possibility of extension, and can pay up to £600 P/D Requirements: Strong experience working with C#/.Net Experience working with Cloud Technologies (Azure preferred) Finance experience a plus! Strong Communication skills with a drive to be working with the best tech! If this sounds like your next contract and you...

SC Cleared Java Consultants (Senior Software Developers / Java Architects) with good experience of Camunda BPM (ideally to v8 but v7 considered), are required by my consultancy client. To be considered, you must hold SC Clearance and be either a senior / lead Java Software Engineer or a Java Technical Architect with strong project knowledge of Camunda BPM. These roles will be outside IR35 and on a hybrid working basis. ONLY   SC Cleared candidates with good Camunda experience will be considered. Please send your CV in the first instance and if relevant you will be contacted with full role and company information.  

Senior AI Engineer | £700/day Outside IR35 | 6-Month Contract Industry: Technology / Capital Markets Location: London - 3 days in office Job Type: Contract Our client, a forward-thinking technology organisation, is seeking a Senior AI Engineer to join a team building production-grade AI systems powered by large language models (LLMs). You will work closely with software engineers and product stakeholders to design, develop, and deploy scalable AI applications, focusing on multi-agent orchestration, intelligent tool integration, and reliable production workflows. Responsibilities Design and implement LLM-powered AI systems, including RAG pipelines, vector/knowledge databases, and agentic frameworks. Build and maintain production-grade AI applications with clean code, APIs, data pipelines, and robust error handling. Develop and maintain evaluation frameworks to measure and monitor system performance, accuracy, and reliability. Implement feedback loops...

Role: AWS Cloud Platform Engineer Location :London Contract : 6 Months + Extension Type : outside IR35 Years of Experience: 6+ Mode : Hybrid -3 days Maintain and improve AWS cloud infrastructure for 24/7 bank operations, focusing on stability, performance, security, and compliance Enhance connectivity between AWS accounts, client, and third parties to ensure secure and reliable customer experiences Design and create automation scripts and tooling using Bash, Python, and Go Language mandatory Build and support cloud platforms for application developers, improving SDLC and developer experience Manage vendor relationships and coordinate project efforts across business areas Participate in on-call rotation to support platform reliability Required Qualifications, Capabilities, and Skills: Formal training or certification on software engineering concepts and advanced applied experience Hands-on experience with AWS and infrastructure as code...

Software Engineer (Java Focus) | up to £650 Outside IR35 | Active SC Clearance Required | 1 day a week on site in London Key Responsibilities Develop end-to-end web applications using Java 21/Kotlin (Spring Boot 3) and modern frontends utilising TypeScript and Nunjucks templates. Build and consume secure RESTful APIs and complex Middleware solutions that integrate seamlessly with distributed government systems. Architect asynchronous messaging patterns , utilising message brokers to handle high-volume, event-driven data flows and system-to-system communication. Design and maintain polyglot persistence layers , including SQL (PostgreSQL) and NoSQL databases, ensuring optimal schema design and data integrity. Own the full testing life cycle by adopting a "Devs-as-Testers" philosophy, writing comprehensive unit, integration, and end-to-end tests for every feature delivered. Manage Infrastructure as Code (IaC) using Terraform and Scripting to provision and...

Role: AWS Cloud Platform Engineer Location :London, UK Contract : 6 Months + Extension Type : outside IR35 Years of Experience: 6+ Mode: Hybrid -3 days Maintain and improve AWS cloud infrastructure for 24/7 bank operations, focusing on stability, performance, security, and compliance Enhance connectivity between AWS accounts, client, and third parties to ensure secure and reliable customer experiences Design and create automation scripts and tooling using Bash, Python, and Go Language mandatory Build and support cloud platforms for application developers, improving SDLC and developer experience Manage vendor relationships and coordinate project efforts across business areas Participate in on-call rotation to support platform reliability Required Qualifications, Capabilities, and Skills: Formal training or certification on software engineering concepts and advanced applied experience Hands-on experience with AWS and infrastructure as code...

Role: AWS Cloud Platform Engineer Location :London Contract : 6 Months + Extension Type : outside IR35 Years of Experience: 6+ Onsite /Hybrid/Remote- : Hybrid -3 days Maintain and improve AWS cloud infrastructure for 24/7 bank operations, focusing on stability, performance, security, and compliance Enhance connectivity between AWS accounts, client, and third parties to ensure secure and reliable customer experiences Design and create automation scripts and tooling using Bash, Python, and Go Language mandatory Build and support cloud platforms for application developers, improving SDLC and developer experience Manage vendor relationships and coordinate project efforts across business areas Participate in on-call rotation to support platform reliability Required Qualifications, Capabilities, and Skills: Formal training or certification on software engineering concepts and advanced applied experience Hands-on experience with AWS and infrastructure as...

Senior Full Stack Developer (Contract) Outside IR35 | Remote | Up to £600/day Overview We're partnering with a specialist software consultancy delivering business-critical platforms across financial services and pensions. They're looking for a Senior Full Stack Developer who enjoys proper engineering - clean architecture, ownership of solutions, and working alongside experienced senior engineers and QA specialists. This is a hands-on delivery role (no line management, no ticket-factory environments) with meaningful technical influence across the full stack. What you'll be doing Designing and building end-to-end full-stack solutionsin a modern cloud environment Backend development using Python and C# Frontend development with TypeScript and React Working within Azure (Functions, Azure SQL, Service Bus, ADF) Contributing to architecture discussions, technical design, and code reviews Applying pragmatic AI-assisted/agentic engineering practices to improve delivery...