A Senior Full Stack Developer is needed to work with Angular, .NET, and legacy ASP.NET MVC. The role involves developing, enhancing, and modernising business-critical Front Office applications for an Investment Bank.

Full Stack Developer role using C#, .NET, JavaScript, and Umbraco for an established luxury travel company. The work involves a major transformation programme building web-based tools to automate operational tasks, improve pricing accuracy and management information, plus website enhancements.

C# .NET developer role at a boutique FX brokerage specializing in currency options and interest rate swaps. Requires 3-5 years’ C# .NET experience, ideally with FX project understanding, joining the London team.

Work with .NET to design, build and improve secure, reliable software. As part of multidisciplinary delivery teams at a digital consultancy, you will deliver complex technology programmes for critical public sector digital services.

You'll work with JavaScript, Java, .Net, or Python; version control (e.g., Git, Mercurial); CI/CD tools (e.g., Jenkins, TeamCity); and automated testing frameworks. The team collaboratively designs and builds proof-of-concept or production systems.

You'll work with AWS, GCP, SIEM, EDR, DLP, MDM, Python, Go, and TypeScript. Risk Ledger builds a network for supply-chain organisations to share security maturity and visualise risks. You'll mature security operations, detection, incident response, and cloud security across cloud, endpoint, and SaaS environments.

Work with Python, Jenkins/Groovy, pytest, GTest, and CI/CD pipelines to build automation, tooling, and test frameworks for SDK teams across Linux and Windows environments. You'll develop quality engineering practices—automated tests, diagnostics, reporting, and developer feedback loops—to improve the reliability and delivery of SDK solutions. The role spans SDK teams in London, Bristol, and Dublin.

Expedia Group★3.8 (1.2k)· London

The iOS engineer will work with Swift, SwiftUI, Xcode, Git, and AI-assisted tools like Claude Code, handling UI patterns, animations, testing, and debugging. They join Expedia Group’s Design System team, building reusable UI patterns and experiences across the company’s travel platforms. The team’s scope isn’t specified.

You will work with REST APIs, FIX protocol, JSON, SQL, command-line tools, and Python scripting to lead technical implementations and connectivity integrations for institutional clients. The role manages end-to-end onboarding of exchanges, liquidity providers, and clients onto Talos’ institutional-grade digital asset trading platform, handling platform configuration and troubleshooting. This is an implementation-focused role, not production support, requiring 3+ years of capital markets or fintech experience.

Proton★5.0 (1)· London

You will work with .NET, Windows desktop application development, multi-threaded programming, file systems, Git, GitLab CI/CD, and monitoring/alerting frameworks. You’ll build and maintain Proton Drive for Windows, a privacy-by-default application that manages local and remote state and performs cryptographic operations.

You'll work with JavaScript, Node.js, Express, React, and MongoDB/Mongoose to set technical direction and oversee AI-assisted content-creation features. As Fractional Head of Product at StoryTerrace, you'll own the roadmap for two B2C platforms—an established product and a new self-serve app—directing one Full Stack Developer and advising on hiring. This role reports to the CEO and requires hands-on coding experience to unblock development.

Sunlighten UK & Europe★2.0 (1)· London

You’ll work with Five9 (or comparable contact-center platforms), Salesforce Sales/Service Cloud, REST APIs, Zapier, and possibly JavaScript, Python, or .NET to build IVR, dialer, lead-routing, live-chat, and SMS integrations. The role owns Sunlighten’s UK omnichannel customer-engagement platform, connecting customers with Sales and Customer Care across voice, digital, and messaging channels. No team size is stated.

HCLTech★3.7 (11k)· London

Work with Java, Selenium, Playwright, Postman, JMeter, Jira, SQL, GitHub, Git, CI/CD, Jenkins, and Azure DevOps. Design and execute manual and automated tests for web, mobile (iOS & Android), API, and backend systems, validating merchant onboarding, payment processing, settlement, and terminal management for Lloyds Banking Group.

Meta★4.0 (1.1k)· London

Work with languages such as C++, Java, Swift, Kotlin, Python, JavaScript, and Hack to build and optimize user-facing applications across mobile and web. As a member of Meta’s product engineering teams, you’ll help advance its platforms—Facebook, Instagram, WhatsApp, and immersive AR/VR experiences—that connect billions globally.

You'll work with Java/JVM and Spring on the backend, React/JavaScript/TypeScript on the frontend, plus CI/CD, distributed systems, and relational/non-relational databases. You'll join Wise's Account Integrity team, building fraud-prevention and financial-crime detection systems to protect customer accounts. Wise is a global technology company for moving and managing money.

Alto★2.7 (212)· London

Fullstack engineer role working with TypeScript, Node.js, C#, .NET, React frontend, and AWS services (ECS/Fargate, Lambda, SQS, DynamoDB, DocumentDB), plus Terraform, SST, and AI coding agents like Claude Code and Cursor. You'll build microfrontend web apps and evolve event-driven architecture for Alto Software Group, a B2B SaaS platform powering UK housing transactions. This is a 12-month maternity cover position.

Sainsbury’s★3.5 (16k)· London

You will build and integrate server‑side logic for the Multichannel Messaging Hub, using Node.js, TypeScript, microservices, REST/JSON/SOAP APIs, Kafka, Snowflake, AWS serverless services, Kubernetes, and Terraform. The team of 7 engineers owns cross‑channel campaign delivery for Sainsbury’s brands.

Standard Chartered★4.1 (3.3k)· London

Senior developer role on Standard Chartered’s Blade platform (in-house pricing, execution, and trade processing) using JavaScript, TypeScript, React, Redux, RxJS, Webpack, CSS, HTML, Azure DevOps CI/CD, and preferably Java backend.

You’ll develop secure data and system integrations across Azure middleware—APIM, Logic Apps, Service Bus, Functions, Data Factory, Synapse, Data Lakes—using C#, .NET, PowerShell, SQL/NoSQL, Azure DevOps, Terraform, React, and AI tools like GitHub Copilot. You’ll join AELTC’s Technology team, which supports IT systems year-round and during The Championships.

You will build and maintain server-side applications and APIs using Node.js, Python, Java, C#, PHP, and Ruby on Rails, working with MySQL, PostgreSQL, MongoDB, and cloud platforms AWS and Azure. You will join the development team to design scalable backend systems for the company’s web platforms, collaborating with front-end developers using Angular and React.

Citi★3.9 (21k)· London

You will work with TypeScript, React, HTML5, CSS, JavaScript (ES6+), Chromium/Electron/OpenFin, FDC3, REST/WebSocket APIs, Kafka/Solace/Tibco, and CI/CD with Jenkins. The team delivers pricing solutions and trading GUIs for Citi’s Foreign Exchange business. You will provide technical leadership, mentor junior engineers, and drive AI integration.

You'll work on Akeneo Activation, a next-generation product syndication platform that transforms and distributes PIM data to retailers and marketplaces globally. The role involves full-stack development using Node.js, React, Next.js, and GCP serverless architecture, building scalable cloud solutions and mentoring engineers across the team while collaborating with cross-functional stakeholders.

Work with Microsoft Fabric (Lakehouses, Warehouses, Dataflows, Pipelines), Azure (SQL, Data Lake, Data Factory), SQL, Python, and REST API/SFTP to build ETL/ELT solutions. You will deliver modern data integration solutions for a diverse portfolio of clients within RSM’s Global VAT Team.

Lead a disputes team at Checkout.com, working with a .NET/C# back end, React/TypeScript front end, and Python for machine learning, alongside REST APIs, event-driven microservices, and SQL. The team builds tools and models to help merchants manage and win chargeback disputes at scale. You will oversee engineers across disciplines and seniority levels, driving predictable delivery and operational efficiency.

Use Selenium, Playwright, Postman, JMeter, Jira, SQL, Git, Jenkins, and Azure DevOps to design and execute manual and automated tests. Validate merchant onboarding, payment processing, settlements, terminal management, and Lloyds Accept application flows across web, mobile (iOS/Android), and API systems.