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.

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.

Lead Software Engineers use TypeScript, Java, Golang, Rust, Python; deploy on Kubernetes and Google Cloud; and work with BigQuery, REST, and observability tools. They build and scale supplier integration, search/recommendation, real-time pricing, ML marketing, booking/payment/fulfillment, and AI-powered systems for the company’s packaged-holiday platform.

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.

PA Consulting★3.7 (106)· London

You will build and lead a Forward Deployed Engineering unit, working with Domain-Adapted Language Models, Small Language Models, LLM fine-tuning, RAG, agentic workflows, evaluation frameworks, and MLOps. The team deploys production AI systems for strategic clients, growing from a founding cohort of 8-12 to a 100-plus person team.

Build REST and GraphQL APIs and MCP servers in Python (FastAPI, Flask) to expose ML models from Databricks to internal apps, CRM platforms, and AI agents at RBC. Work within the Data Science team to architect the serving layer, handling contract design, authentication, and documentation.

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.

You'll design AI-native information architecture, build operating rhythms (OKRs, business reviews), and manage investor relations. Fleek is building the AI-powered infrastructure for the secondhand clothing trade, operating a B2B marketplace and FleekSort AI. You will help align a 200-person team across three geographies.

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.

You will work with Python, SQL, BM25, vector search, reranking, RAG, and agentic systems to own and evolve Corestream, Kharon’s risk intelligence feed that surfaces entity-level insights and risk narratives for customers in global security, sanctions, and financial crimes.

Python, SQL, BM25, vector search, reranking, and RAG pipelines powering agentic systems. You will own and evolve Corestream, Kharon’s risk intelligence feed, redesigning semantic search and narrative generation for global-security insights.

Build and deploy AI agents for geopolitical and financial risk intelligence, working with Python, SQL, RAG pipelines, BM25, vector/hybrid retrieval, APIs, Docker, Kubernetes, GitHub Actions, and AWS services like RDS, EKS, and S3. Kharon provides risk-analysis tools for global financial institutions and multinationals, covering sanctions, export controls, and threat identification.

Architecting Sitecore solutions (XP/XM, SitecoreAI, Content Hub, Search, CDP, Personalize, Stream) with Next.js, React, TypeScript, Azure, microservices, APIs, and DevOps. You lead technical delivery for client projects at a digital transformation firm, removing blockers and creating blueprints for delivery teams.

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.

You will build with TypeScript, React, and SQL, using tools like GrowthBook, PostHog, LaunchDarkly, Statsig, Amplitude, Customer.io, and agentic coding tools such as Claude Code or Cursor. You'll join a small, senior engineering team at a seed-stage AI startup creating an AI employee that drafts client work for small businesses, owning the product's growth and activation funnel end-to-end.

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.

Chubb Insurance★3.7 (1.3k)· London

You will use Python, Hugging Face Transformers, LangChain, LlamaIndex, PyTorch, TensorFlow, Docker, and cloud platforms to build and deploy LLM, RAG, and conversational AI applications. As part of Chubb Insurance's Global Analytics team, you'll design production-ready AI solutions for business value.

Cognizant★3.8 (17k)· London

You will work with Python (FastAPI or Flask) in a serverless architecture, integrating with a NextJS/React frontend and third-party APIs. You will help build and enhance the NHS Digital Onboarding Service (DOS) for the NHS API Platform.

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 work with Python, React, TypeScript, and AI coding agents across the full stack. TreasurySpring is a London fintech building a regulated Fixed-Term Fund platform that replaces manual institutional treasury processes and legacy systems with digital cash-management products for investors and corporations.