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.

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.

Blockchain★3.4 (14)· London

Lead a small engineering team building crypto savings and crypto-backed lending products at Blockchain, using Kotlin or Java, Kafka, PostgreSQL, and Redis. You will define technical architecture, design distributed systems, and drive best practices in a hands-on role.

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.

TypeScript, React, Node.js (Bun where it fits), Kubernetes, and AWS. This Staff Engineer sets technical direction for the Financial Services team, building web apps, back office systems, and tooling that power financial product comparison.

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.

Java, PostgreSQL, Oracle DB, RESTful APIs, Kubernetes, AWS, SQL, and microservices. The role involves developing and testing backend APIs, new services, and database integrations for scalable systems, collaborating with cross-functional teams including DevOps and QA.

Google★4.3 (6.2k)· London

Work with IMS, 3GPP NAS, LTE, and 5G NR protocols. As a firmware engineer on the Pixel Testing Engineering team, you will develop, customize, and test Android/modem software for the IMS/telephony/NAS domain, and develop AI-driven automation for task streamlining.

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 build the UI/UX for AI-powered intellectual property tools using TypeScript, React, and full-stack frameworks, with Python backend and WYSIWYG editors (TinyMCE/CKEditor) for patent attorney workflows. Solve Intelligence provides AI infrastructure for the IP industry, serving 600+ global teams including DLA Piper with 20-30% monthly revenue growth. As a founding engineer on a small, talent-dense team, you'll own product evolution and end-to-end feature delivery across the stack.