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.

Thomson Reuters★3.9 (4.3k)· London

Work with Java and Python across containerized services, relational databases, and distributed systems, including AI/LLM integration patterns. As a Principal Engineer on Thomson Reuters' HighQ, an enterprise collaboration platform for law firms, you will set technical direction, architect scalable systems, and lead the integration of AI and agent platforms.

Amazon★3.5 (56k)· London

This role involves designing and building scalable security systems, with development in Java, C++, or C#. You’ll automate pentest processes and create a greenfield product that provides critical security details about Amazon applications, working with teams across the company. The position involves owning architecture, design, and reliability for new and existing systems.

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.

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.

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.

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 build server-side game logic on a Java code base implementing slot mechanics, reel logic, and bonus flows. Working closely with Game Mathematicians, you’ll own a game from concept through to release, handling configuration, metadata, and client integration. You’ll also refactor and modernise the platform, using Git and working in an Agile Scrum environment.

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.

You'll work with TypeScript/Node.js, React, Java/Kotlin, REST APIs, event-driven architectures, AWS, Docker, Kubernetes, Kafka, Keycloak, and observability tooling. You'll lead the PRIIP Cloud platform, WallStreetdocs' cloud-based documentation and reporting system for structured products and derivatives in regulated financial services. No team size is specified.

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.

Tesco★3.5 (25k)· London

You will work with Java, Spring Boot, Kafka, Apache Flink, Apache Beam, NoSQL databases, Redis, and Apache Camel. The Tesco Personalisation team builds real-time, low-latency services for recommendations, offers, and experimentation across web, mobile, and in-store channels using streaming data and ML.

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.

Build responsive React/TypeScript interfaces with Next.js, Vite, pnpm, Chakra UI, and Storybook; integrate blockchain interactions using wagmi/viem while managing state with TanStack Query and Zustand. You'll develop the frontend for Symbiotic’s onchain collateral infrastructure, powering vaults, stakers, and operators in neofinance applications.

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.

You'll work primarily in Python and PHP, building SDM (Supplier Data Manager), Akeneo's product that automates the extraction, classification, enrichment, and distribution of supplier product data at enterprise scale. The role involves scaling infrastructure for large data volumes, improving AI-powered data pipelines using LLMs, building collaboration features, and shipping production systems while participating in customer discovery across the cross-functional Impact Team.

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.

SitecoreAI (XP/XM, Content Hub, Search, CDP, Personalize, Stream), Next.js, React, TypeScript, Azure, microservices, APIs, and DevOps. You will architect and lead Sitecore solutions for client delivery teams at a digital transformation agency.

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.