13 senior backend developer jobs found in London

Who Are We? Xcelirate develops technologically-advanced platforms which are accessed by thousands of users every minute! We are proud to offer a workplace where the sharpest developers come together to strategically plan and swiftly execute practices which see us maintain our existing market dominance and attain global expansion. We owe our success to our customers who have seen us grow across a decade, and our talented team who have made that growth possible!   What are we looking for? You're a Principal-Level Engineer first. The tech lead title is almost incidental. It just means you're the person the team orbits around, because that's what happens naturally when you're the one who understands the system most deeply and keeps the clearest head under pressure. The 10% that's people management fits inside your engineering work, not alongside it. You hire, you steer, you unblock, but you do it the way a strong engineer does everything: with good...

Who Are We? Xcelirate develops technologically-advanced platforms which are accessed by thousands of users every minute! We are proud to offer a workplace where the sharpest developers come together to strategically plan and swiftly execute practices which see us maintain our existing market dominance and attain global expansion. We owe our success to our customers who have seen us grow across a decade, and our talented team who have made that growth possible!   What are we looking for? You're a Principal-Level Engineer first. The tech lead title is almost incidental. It just means you're the person the team orbits around, because that's what happens naturally when you're the one who understands the system most deeply and keeps the clearest head under pressure. The 10% that's people management fits inside your engineering work, not alongside it. You hire, you steer, you unblock, but you do it the way a strong engineer does everything: with good...

Senior/Lead Java Developer About Synechron: Synechron is a leading digital transformation consulting firm dedicated to delivering innovative technology solutions within banking, financial services, and insurance. We thrive on engineering excellence, collaboration, and a passion for cutting-edge technologies. We are seeking a highly skilled and experienced Senior/Lead Java Developer with 10+ years of hands-on experience in enterprise application development. The ideal candidate must possess strong expertise in core Java fundamentals, concurrency, and distributed systems , along with exposure to AI/ML-driven solutions . This role demands a deep understanding of data structures, system design, performance optimization, and scalable architecture , along with the ability to lead technical initiatives and mentor teams. This role is Inside IR35 contract Job Locatio n: London (Hybrid - 3 days in the offi ce) Key Responsibilities: Design, develop, and...

Who Are We? Xcelirate develops technologically-advanced platforms which are accessed by thousands of users every minute! We are proud to offer a workplace where the sharpest developers come together to strategically plan and swiftly execute practices which see us maintain our existing market dominance and attain global expansion. We owe our success to our customers who have seen us grow across a decade, and our talented team who have made that growth possible!   What are we looking for? You're a Principal-Level Engineer first. The tech lead title is almost incidental. It just means you're the person the team orbits around, because that's what happens naturally when you're the one who understands the system most deeply and keeps the clearest head under pressure. The 10% that's people management fits inside your engineering work, not alongside it. You hire, you steer, you unblock, but you do it the way a strong engineer does everything: with good...

About us Founded in 2019 and part of Y Combinator's 2020 cohort, Photoroom is the leading visual solution for e-commerce. We've raised Series B funding and reached 300+ million users worldwide, processing over 5 billion images annually and serving both small businesses and major enterprises like Amazon, DoorDash, and Decathlon through our mobile app, web platform, and API. We're a remote-friendly team of 100+ passionate builders giving e-commerce businesses superpowers to create visuals that help them grow, making the hardest parts of selling online disappear. We focus on craft, innovation, and collaboration, creating exceptional impact for e-commerce businesses worldwide. Python Engineer – Public API (Contract) Day rate: Negotiable Duration: 6 months Location: Remote. We can hire people already based in selected countries only: France, Germany, Ireland, Italy, Portugal, Spain, UK   About the Role You will design,...

Must have skills: Demonstrable experience with Solidity. Strong understanding of blockchain security practices and potential vulnerabilities. Proficiency in Hardhat and Foundry. Experience with Solidity security testing tools like Slither, Mythril, Echidna Practical experience with scripting languages like Javascript or Typescript. Ability to craft unit, integration, fork, and invariant tests, ensuring code longevity. Demonstrable aptitude for best development practices, data structures, algorithms, and methodologies. Bachelor's degree in Computer Science, Engineering, or a related STEM discipline. Excellent debugging and troubleshooting skills. Strong written and verbal communication skills. Self-motivated with the ability to work in a fast-paced, evolving environment. Proficient communication skills in English. Development background in sectors such as banking, finance, or trading, paired with a comprehensive grasp of financial...

Senior AI Engineer Assignment type: 6 month contract (outside IR35) TMHCC is seeking a Senior AI Engineer to support the build-out of our AI Ops capability and delivery of strategic AI transformation initiatives across insurance operations, including Policy Revamp and FNOL (First Notice of Loss). The role will focus on designing and implementing enterprise-grade Agentic AI solutions using Azure AI Foundry, Python, Azure Functions, and modern cloud-native engineering practices. This is a hands-on engineering role requiring strong experience in AI workflow orchestration, secure Azure architecture, API integration, and scalable AI solution delivery.   Key Responsibilities Design and develop Agentic AI solutions using Azure AI Foundry and Azure OpenAI Build AI orchestration workflows using Python and Azure Durable Functions Develop document-processing and AI-driven automation solutions for insurance workflows Implement secure Azure...

Methods is looking for a Back End Developer specialising in Java Spring Boot and GCP(Google Cloud Platform) to join our team within the private Sector Business unit. Rate: £490 inside IR35 Duration: 6 month initially Location: Hybrid; 3days/w in London office   Requirements:   Architectural Rebuild: Play a role in migrating and rebuilding our core architecture in Java Spring Boot to align with a composable, cloud-native landscape. Connector Development: Design and optimize technical connectors for a diverse mix of global channels, including generalist marketplaces, social commerce (eg, TikTok Shop), and quick-commerce (eg, Glovo, Deliveroo). Catalog Publication Flow: Refocus efforts on rebuilding the catalog publication flow, addressing technical complexities such as category mapping, product variant synchronization, and asynchronous marketplace APIs. Business Logic Migration: Collaborate on transferring complex Legacy...

Must have skills: Demonstrable experience with Solidity. Strong understanding of blockchain security practices and potential vulnerabilities. Proficiency in Hardhat and Foundry. Experience with Solidity security testing tools like Slither, Mythril, Echidna Practical experience with scripting languages like Javascript or Typescript. Ability to craft unit, integration, fork, and invariant tests, ensuring code longevity. Demonstrable aptitude for best development practices, data structures, algorithms, and methodologies. Bachelor's degree in Computer Science, Engineering, or a related STEM discipline. Excellent debugging and troubleshooting skills. Strong written and verbal communication skills. Self-motivated with the ability to work in a fast-paced, evolving environment. Proficient communication skills in English. Development background in sectors such as banking, finance, or trading, paired with a comprehensive grasp of financial...

Straive is a global leader in enterprise-grade data analytics and AI solutions, committed to empowering businesses across various industries with cutting-edge technology and expert insights. Backed by EQT, a top private equity firm, we are uniquely positioned to drive innovation through significant investments and an entrepreneurial spirit.   Our core focus is on delivering advanced Data Analytics & AI Solutions. By combining sophisticated technology with subject matter expertise, we deliver material impact on our clients' topline and streamline their operations. We specialize in providing tailored solutions across financial services, CPG, legal, pharma, life sciences, retail and logistics, helping them build robust data analytics and AI capabilities.   With a client base spanning 30 countries, Straive's strategically located teams operate from eight countries and is headquartered in Singapore. This global presence enables us to offer localized...

Methods is looking for a Back End Developer specialising in Java Spring Boot and GCP(Google Cloud Platform) to join our team within the private Sector Business unit. Rate: £490 inside IR35 Duration: 6 month initially Location: Hybrid; 3days/w in London office   Requirements:   Architectural Rebuild: Play a role in migrating and rebuilding our core architecture in Java Spring Boot to align with a composable, cloud-native landscape. Connector Development: Design and optimize technical connectors for a diverse mix of global channels, including generalist marketplaces, social commerce (eg, TikTok Shop), and quick-commerce (eg, Glovo, Deliveroo). Catalog Publication Flow: Refocus efforts on rebuilding the catalog publication flow, addressing technical complexities such as category mapping, product variant synchronization, and asynchronous marketplace APIs. Business Logic Migration: Collaborate on transferring complex Legacy...

Must have skills: Demonstrable experience with Solidity. Strong understanding of blockchain security practices and potential vulnerabilities. Proficiency in Hardhat and Foundry. Experience with Solidity security testing tools like Slither, Mythril, Echidna Practical experience with scripting languages like Javascript or Typescript. Ability to craft unit, integration, fork, and invariant tests, ensuring code longevity. Demonstrable aptitude for best development practices, data structures, algorithms, and methodologies. Bachelor's degree in Computer Science, Engineering, or a related STEM discipline. Excellent debugging and troubleshooting skills. Strong written and verbal communication skills. Self-motivated with the ability to work in a fast-paced, evolving environment. Proficient communication skills in English. Development background in sectors such as banking, finance, or trading, paired with a comprehensive grasp of financial...

SC Clearance is an essential requirement for this role, as a minimum you must be willing & eligible to undergo checks. Please note, due to the exceptional requirements of this position (short-term nature of this role and speed at which we require a postholder in situ) preference may be given to candidates who meet all of the essential criteria and hold active SC clearance.    The Ministry of Justice (MoJ) priorities include improving public safety and reducing reoffending by reforming prisons, probation and youth justice, and building a justice system which makes access to justice swifter and more certain for all citizens whatever their background. Project professionals in the MoJ help to improve the government's ability to protect the public and reduce reoffending, and to provide a more effective, transparent and responsive criminal justice system for victims and the public.   As a  Lead Developer , your main responsibilities will be:...