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.

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.

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.

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.

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.

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.

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 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.

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 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.

Build backend systems with Kotlin or Java, Kafka, PostgreSQL, Redis, and microservices for a crypto savings and crypto-backed lending platform. This hands-on technical lead defines architecture, remains close to the code, and leads a small team of engineers.

Lead UI Developer role using TypeScript, React, RxJS, WebSockets/SSE, GraphQL, Protobuf, Flatbuffers, Jest/Vitest, React Testing Library, Playwright, and AG Grid. You will own the front-end architecture for a real-time Single Dealer Platform used by Sales, Trading, and institutional clients globally, building low-latency trading applications for market data, pricing, RFQ, and trade capture.

You will build scalable server-side logic using JavaScript, TypeScript, and Node.js in a microservices architecture on AWS with Kubernetes, Terraform, Kafka, and Snowflake. You will join the MMH team within the Martech domain, which orchestrates campaign delivery across email, push notifications, and personalised content for all Sainsbury’s Group brands. The team includes 7 engineers.

Develop backend services using Node.js, Python, Java, C#, PHP, and Ruby on Rails, with databases including MySQL,

You will work with JavaScript (TypeScript), React, Redux, RX JS, NPM/Yarn, webpack, CSS, HTML, Azure DevOps CI/CD, and Java. As a senior developer on the FM Digital Channels team, you will build Blade, the bank's strategic in-house pricing, execution, and trade processing platform for Financial Markets.

You will work with Java, Git, Jira/ClickUp, and Agile Scrum. You own the server-side game logic for online slot games, implementing core mechanics, reel logic, and bonus flows, and coordinating with Game Mathematicians from concept to release.

Lead Python Developer role using Core Python, Flask, VueJS, JavaScript, CSS, HTML, SQL, AWS, Terraform, Docker, and serverless components, with CI/CD and Agile practices. The developer builds, enhances, and supports production applications within UK public sector programmes, collaborating with delivery, product, and data teams.

You’ll build cloud-native applications for a leading global financial institution, using Java with Spring Boot and React to support critical financial operations.

Full-stack Java development on Linux/Unix, using AI coding tools like Claude Code, Windsurf, Devin, or GitHub Copilot. The role is for Ascendion, a technology services company.