24 backend engineer jobs found in London

Backend Engineer – C#, .Net, Azure | Payments Financial Services | £600/day outside IR35| Hybrid We’re partnering with a leading financial services firm in the FinTech payment space that’s investing heavily in modernising its technology stack. With a new tech leader driving innovation, the focus is on building in-house systems that are scalable, reliable, and future-ready. About the Role Backend Engineer position You’ll take ownership of building and enhancing key client-facing applications using C#, .Net, Azure . As a Backend Engineer you will have tried and tested experience joining a FinTech/Financial Services company at the stage of 0-50 employees. This company is looking to grow significantly, building out 4 new engineering teams include Seniors and Team Leads. The work spans complex financial products, so you’ll have the chance to engage with both technical and business stakeholders across the UK. 💰 Paying up to £600 per day (Outside IR35) 🏢 1–2 days...

Backend Engineer – C#, .Net, Azure | Payments Financial Services | £600/day outside IR35| Hybrid We’re partnering with a leading financial services firm in the FinTech payment space that’s investing heavily in modernising its technology stack. With a new tech leader driving innovation, the focus is on building in-house systems that are scalable, reliable, and future-ready. About the Role Backend Engineer position You’ll take ownership of building and enhancing key client-facing applications using C#, .Net, Azure . As a Backend Engineer you will have tried and tested experience joining a FinTech/Financial Services company at the stage of 0-50 employees. This company is looking to grow significantly, building out 4 new engineering teams include Seniors and Team Leads. The work spans complex financial products, so you’ll have the chance to engage with both technical and business stakeholders across the UK. 💰 Paying up to £600 per day (Outside IR35) 🏢 1–2 days...

London, UK Contract Up to £700p/d (Outside IR35) We’re working with an early stage start up focused on AI HR tooling to drastically improve performance and efficiency. They are a small, focused team looking for a Senior Backend Engineer to help them scale up their AI platform and make a real impact. They are looking for an engineer with strong commercial use of either Java, Kotlin or Scala and proficiency with Python to help modernise their codebase. Responsibilities: Build and scale backend systems for AI-driven automation products Collaborate with product and frontend teams on planning and decision-making Contribute to architecture, design, and scaling efforts Manage CI/CD pipelines and cloud infrastructure deployments Collaborate directly with our CEO and CTO to architect end-to-end backend solutions Key Requirements Strong programming skills in the JVM ecosystem Some proficiency in Python 6+ years of backend development experience...

Lead Backend Engineer - HIRING ASAP Start Date: ASAP Duration: 6 months Location: Remote Rate: £500 - £600 per day, outside IR35 Summary This position is suited for Senior folks, who are motivated, proactive, not afraid to take leadership and are confident to make decisions but are also good team players and have a very good technical skill. Tech stack you will be working in is NodeJS + PSQL + AWS. Responsibilities NextGen and MDM systems, which are the main engines that are powering our clients' websites. You should take a tech lead on these services and be able to mentor others, work with EM/Delivery/Product etc. Good tech skills and design principles are probably key here. Key Skills Experience within NodeJS + PSQL + AWS. iGaming, or Casino Betting industry experience preferred.

Location: Stratford, London Rate: £400–£450 per day (Outside IR35) Contract Length: 6-12 months Client: Global Consultancy (End Client: Confidential Financial Institution) We are partnering with a global consultancy who are delivering an AI‑driven automation and orchestration programme for a major enterprise client. They require an experienced AI Engineer / Senior Python Engineer with strong microservices experience, LLM integration and AWS serverless expertise to support the build of an intelligent prompt‑orchestration platform powered by AWS Bedrock. Key Responsibilities Develop and maintain Python microservices, serverless functions (AWS Lambda), backend APIs and Python packages Build LLM‑powered agents, orchestration flows and MCP servers using AWS Bedrock Analyse logs, traces and evaluation outputs from a live AI product environment Design and maintain REST APIs interacting with AWS services including OpenSearch, DynamoDB, Kendra and S3 Build and...

Salesforce Engineer | £400 – £450 | Outside IR35 | 6 Months | Remote First   We’re recruiting for an experienced Salesforce Engineer for a 6-Month contract role. This position will play a key role in leading Salesforce refactoring, modernising backend systems, and driving modern engineering practices across our clients platform. Offering £400 - £450 per day, this role is determined as Outside IR35 and may require occasional travel to the office most local to you.   Key Requirements Take ownership of large‑scale Salesforce Apex refactoring and backend process improvements Enhance Salesforce integration architecture, reliability, CI/CD, and automated testing Drive modern engineering practices and support AI‑assisted development tools Resolve technical debt, improve performance, and ensure scalable architecture Requires strong Salesforce Apex, Java, CI/CD, integrations, automation, and refactoring experience Previous experience working in Fintech or regulated...

Salesforce Engineer | £400 - £450 | Outside IR35 | 6 Months | Remote First We're recruiting for an experienced Salesforce Engineer for a 6-Month contract role. This position will play a key role in leading Salesforce refactoring, modernising backend systems, and driving modern engineering practices across our clients platform. Offering £400 - £450 per day, this role is determined as Outside IR35 and may require occasional travel to the office most local to you. Key Requirements Take ownership of large-scale Salesforce Apex refactoring and backend process improvements Enhance Salesforce integration architecture, reliability, CI/CD, and automated testing Drive modern engineering practices and support AI-assisted development tools Resolve technical debt, improve performance, and ensure scalable architecture Requires strong Salesforce Apex, Java, CI/CD, integrations, automation, and refactoring experience Previous experience working in Fintech or...

Senior Full-stack Python Typescript AI Engineer- Outside IR35   ROLE   This position is for a Senior Backend Developer working in python and typescript to support the development on a SaaS product with a focus on Ai.   This role involves designing, building, and optimising scalable backend services and APIs to support a single-tenant, multi‑instance SaaS platform, while contributing to the architecture and implementation of AI‑driven components such as Retrieval‑Augmented Generation (RAG) pipelines, vector databases, semantic search, and structured or knowledge‑graph‑based data modelling approaches. You will support the design of robust data models and pipelines capable of handling both structured and unstructured data with strong traceability and auditability, and help transition prototypes into production‑ready systems with a focus on security, access control, performance, reliability, observability, and monitoring. The role also includes building and managing...

Data Engineer l AWS l Terraform l Python l DynamoDB l Backend l API l 3-Month Contract to permanent | £500- £525 per day | Remote hybrid We 're supporting a fast-growing health tech organisation looking for a hands-on Data Engineer to help stabilise and scale their AWS serverless pipelines. With rapidly increasing data volumes, they need someone who can bring automation, structure, and production-ready engineering. The Role Improve and maintain pipelines across Lambda, AppSync, DynamoDB, Postgres, SQS, ECS, and Step Functions Standardise fragmented legacy processes into scalable, automated workflows Support internal and participant-facing applications Work closely with the outgoing engineer to ensure smooth knowledge transfer Must-Have Skills Strong Terraform Deep AWS serverless experience Python for production workloads Solid DynamoDB knowledge Nice to Have GraphQL / AppSync Node.js or Python API background...

AI Engineer (Contract) – £500/day Outside IR35 📍 Canary Wharf, London (3 days onsite) 🇬🇧 UK-based applicants only We’re looking for experienced AI Engineers who think holistically, automate relentlessly, and know how to turn modern AI capabilities into production-grade, high-impact applications . Our AI organisation is building real-world AI products that deliver business value at speed. This role is ideal for seasoned engineers who combine strong software engineering fundamentals with a pragmatic, hands-on approach to AI tooling and infrastructure. What you’ll be doing Designing, building, and maintaining production-grade AI applications using modern engineering practices (CI/CD, testing, observability, cloud-native design). Developing reusable AI platforms and tools (e.g. conversational bots, AI-powered search, unstructured data processing, GenAI solutions). Working in cross-functional, embedded teams with business stakeholders to rapidly deliver...

Senior Java Engineer (Low Latency / Trading Systems) - £950-1150/Day Outside IR35 Contract London (Hybrid) | High-Performance, Real-Time Platform We’re working with a high-performing engineering team building real-time, high-throughput systems at the core of a complex trading and data platform. This is a hands-on contract role focused on designing and optimising low latency Java systems that process live market data, power pricing and risk engines, and support high-frequency decision-making. You’ll be operating in an environment where performance is critical, latency is measurable, and engineering quality directly impacts production systems. What you’ll be working on Building and optimising low latency, high-throughput Java systems for real-time data and trading workflows Designing components within a distributed, event-driven architecture handling large-scale streaming data Developing pricing, risk, and data processing systems used in live...

Senior Golang / Go Engineer - Contract - £500 per day (Outside IR35) - London A well known UK tech business is looking for a Senior Golang / Go Engineer to join on an initial 2 month contract, with a strong chance of extension. Key details * Up to £500 per day (Outside IR35) * Initial 2 month contract * 80% backend (Golang) with some React * 1 day per week onsite in London * ASAP start * Fast interview process This is a hands on role building scalable backend services and APIs. They're looking for someone product focused who understands the user journey, with experience around observability and system reliability. You'll need to be a senior engineer who can take ownership, lead projects, and drive delivery, even if you're not formally a Lead Engineer. Apply now for more details. Interviews are moving quickly.

🚀 Building a Senior AI Engineering Team (LLM + Distributed Systems) Global Investment Bank | Capital Markets Platform 📍 London (1–2 days onsite) 💰 £700–£1,200/day (Outside IR35) Contract to permanent available 📅 12-month contracts The Mandate We are building a production-grade AI platform inside a global investment bank. This is not a research team or a chatbot project. This is engineering-heavy , focused on integrating LLM systems into large-scale, distributed environments used by trading and quant teams. We are hiring across multiple levels: Lead Engineer (Agentic / RAG focus) Architect (end-to-end platform design- Agentic / RAG focus) Senior Engineers (x3) Agentic / RAG focus Potential Director-level hire to oversee the function What This Role Requires (Read Before Applying) You must have: Experience building distributed systems at scale Strong background in backend or data engineering Proven experience working on...

Contract Opportunity: AI Engineer (GenAI) Fully Remote (UK-based) Outside IR35 - £550 - £600 p/d DOE Start Date: 19th May Contract Length: 6 months (Full time) What you'll need: Strong Python engineering background (AI/ML or backend) Experience building with LLMs (LangChain, LlamaIndex, or LangGraph) Familiar with vector databases for embedding/indexing with images, audio, text and video Familiar with different multi-agent system patterns Comfortable with FastAPI or Flask Strong cloud experience (GCP or AWS) Nice to have: GCP experience Background in ML projects Experience working on data-heavy applications Familiarity with CI/CD pipelines If you're available from 19th May and interested in a short-term, high-impact GenAI project.

Full Stack Engineer (Outside IR35) £450 - £475 per day Fully Remote + Outside IR35 + Remote + Company Training + 3 month initial 1x Extension Expected Are you a Full Stack Engineer that wants to work fully remote for a UK based tech giant that is building a state of the art inhouse CRM system? Do you want to work in a small tightknit team with other senior engineers and developers that are finalising a long term project with the potential to have at least 1 if not 2 extensions? This company have a newly formed UK operations but are backed by a global leader in the digital marketing space. The ideal candidate will be a Full Stack Engineer with experience with JavaScript, TypeScript, MongoDB, React and Node.js and are happy to work fully remote. THE ROLE: Design, deploy and maintain clean code Build scalable backend services in Node.js and TypeScript Design and maintain relational and document databases in PostgreSQL and MongoDB Troubleshoot all systems to ensure...

We are seeking a passionate Software Engineering Manager who will provide technical expertise and operate with excellence. Being creative, curious, and confident, you will be an integral part of our empowered, self-managing, multi-disciplinary engineering teams - designing, building, releasing, and maintaining products. You will play a key role in driving our ambition to create a best-in-class software engineering team, environment, and culture. This is an initial 6 month contract (outside IR35) that requires you to work on client site 3 days a week in London, Paddington.   Your key accountabilities will include: • Team Management: Build, mentor, and manage a high-performing software engineering team. Foster a culture of collaboration, innovation, and continuous improvement within the team. Facilitate communication and collaboration among team members. Ensure budgets, people and resource allocation, and workload, balance across projects. • Agile Delivery:...

Senior JavaScript Engineer contract - Outside IR35 - £575 per day Leading Ecommerce client is now recruiting a talented ‘Full Stack JavaScript Developer’ who is proficient in front and back-end development. (React/Node.js), with an emphasis on backend Node work initially. This role will be joining their platform team, designing, and building the foundations of which our clients innovative web and mobile applications run on. What will a day in the role entail? Working as an integral part of an agile team contributing towards the planning and development of systems/platforms. Collaborating with engineers, product owners and business analysts to define solutions, ways of working and share knowledge across the department. Reviewing code and providing support to members of your team. Working on client-facing applications in react / next.js Designing and building Node.js / GraphQL APIs. The ideal Senior JavaScript Engineer Senior level experience in modern...

Senior Software Engineer – Java (Contractor) Outside IR35 Rate: £400 - £500 per day Duration: 3 Months Plus Start Date: ASAP As a Senior Software Engineer (Java) – Contractor at Pulselive, you’ll be focused on delivering robust, high-performance backend services and APIs that power digital experiences for millions of sports fans globally. This role is ideal for an experienced, hands-on engineer with strong Java and Spring expertise who thrives in a collaborative and fast-paced delivery environment. You’ll work closely with cross-functional teams to build, integrate, and optimize systems that handle real-time sports data, video, and live commentary. This position is project- and delivery-focused, with no line management or people-leadership responsibilities required. Key Responsibilities: Design and develop scalable backend systems using Java and Spring Boot Deliver well-structured, maintainable, and testable code aligned with project...

Full job description Senior Software Engineer – Java (Contractor) Outside IR35 Rate: £400 - £500 per day Duration: 3 Months Plus Start Date: ASAP   As a  Senior Software Engineer (Java) – Contractor  at Pulselive, you’ll be focused on delivering robust, high-performance backend services and APIs that power digital experiences for millions of sports fans globally. This role is ideal for an experienced, hands-on engineer with strong Java and Spring expertise who thrives in a collaborative and fast-paced delivery environment. You’ll work closely with cross-functional teams to build, integrate, and optimize systems that handle real-time sports data, video, and live commentary. This position is project- and delivery-focused, with no line management or people-leadership responsibilities required.   Key Responsibilities: Design and develop scalable...

Frontend Developer (Contract) - Fully Remote (UK Based) Role: Frontend Developer (Contract) Location: Fully Remote (UK) Contract Length: 6 Months (Initial) Day Rate: £400–£500 per day (Outside IR35) Start Date: ASAP 🚀 The Opportunity We’re working with a fast-growing digital product company that is scaling its engineering team to support a major platform rebuild. They are looking for a highly experienced Frontend Developer to join on a contract basis and help deliver a modern, high-performance web application used by thousands of users across the UK. This is a fully remote role (UK-based), offering the chance to work on a greenfield product with a strong engineering culture and autonomy. 🛠️ Responsibilities Build and maintain scalable frontend applications using modern frameworks Collaborate closely with designers, backend engineers, and product managers Contribute to architecture decisions and technical direction Implement responsive,...