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.

Lead platform engineering for internal shared data and AI capabilities, including ingestion, integration, canonical APIs, and agent workflow platforms with orchestration, monitoring, evaluation, observability, and guardrails. The team builds scalable, reliable platform services for LexisNexis Intellectual Property Solutions, enabling data-driven innovation and production-grade AI workflows across multiple product domains.

The role involves workflow automation, onboarding/offboarding, IT, AV, and AI tools. Omnea builds an AI-native procurement platform that automates approvals, supplier risk, and spend visibility for enterprises. You will support logistics, office administration, and internal operations as the company scales.

Work with TensorFlow or PyTorch, Python, and related computer vision/graphics libraries on neural network architectures (convolutional, recurrent, transformer, diffusion-based). The Visual Computing Group (VCG) researches and develops generative models for game rendering and live video streaming to advance state-of-the-art runtime efficiency, visual quality, and latency.

The technical lead will work with Java/J2EE, RESTful web services, Spring Boot, microservices, cloud technologies, Docker, Kubernetes, and CI/CD pipelines. They oversee architecture, design, and development of Java/J2EE applications, lead a team of developers, and drive technical excellence and best practices.

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.

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.

Lead Software Engineer for the PRIIP Cloud platform, owning full-stack development with TypeScript/Node.js, React, Java/Kotlin, REST APIs, event-driven architectures, AWS, Docker, and Kubernetes. The team builds a cloud-based PRIIP documentation and reporting system for regulated financial services, collaborating with compliance, quant, and product specialists. This role leads a multidisciplinary team of engineers and subject matter experts.

You'll use Java, Kafka, Flink, SingleStore, HDFS/S3, and Scala to build high-performance, low-latency data systems. The Data Platform team in Global Markets owns the post-trade stack, processing high volumes of data and developing an AI-powered analytics UI/agent framework.

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.

Work with Java/Spring, React, JavaScript/TypeScript, CI/CD pipelines, and distributed systems. You'll join the Account Integrity team building a globally scalable fraud prevention engine to protect customer accounts and prevent financial crime using machine learning and real-time monitoring.

You will study for certifications including Azure Fundamentals, CompTIA Network+, Cisco CCNA, and Forescout FSCA, while gaining hands-on practice with Cisco networking, Azure cloud, Splunk SIEM, and Tenable vulnerability management. Newto Training’s programme combines live instruction and real-world project work to prepare you for a network engineer role.

You'll use Python, SQL, shell scripting, containerization, infrastructure-as-code tools, and Scala/Java or Python to build and maintain scalable data pipelines. You'll support a financial technology company's data infrastructure, contributing to AI/ML experiences and international applications. No team size is stated.

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.

Use object-oriented programming (Java or C#), Salesforce Lightning, Force.com, Apex, SOQL, JavaScript, Git, Jira, IntelliJ, CI/CD, and Salesforce REST APIs. Hackajob Ltd is a platform that connects developers with job opportunities. This Salesforce Developer role delivers complex business and technical requirements on the Force.com platform.

Working with AUTOSAR Classic, you will implement and validate security foundations including HSM integration, Secure Boot, Secure Diagnostics, and Secure Programming. This contract role supports a company specializing in electro-mechanical systems for the automotive/EV industry.

Citi★3.9 (21k)· London

You will work with Java, Spring, Web3J/Web3JS, Solidity, Docker, and Hardhat/Foundry to build Citi’s Integrated Digital Assets Platform (CIDAP), integrating blockchain networks and digital asset infrastructure.

Citi★3.9 (21k)· London

Backend Java developer building the Citi Integrated Digital Assets Platform (CIDAP) using Java Spring, web3 libraries (Web3J/Web3JS), Solidity, and containerized DevOps tools (Git, Jenkins, Helm).

Citi★3.9 (21k)· London

Work with Solidity, Web3J/Web3JS/Ethers.js/Viem, Java/Spring, Node.js, and blockchains such as Ethereum, Hyperledger Besu, Canton, and Solana, using Hardhat/Foundry/Truffle for testing. Contribute to Citi's Integrated Digital Assets Platform (CIDAP) building Web3 components for tokenization, smart contracts, and on-chain settlement.

Goldman Sachs★3.9 (2.3k)· London

Build a high-performance, low-latency data platform for post-trade processing using Java, Kafka, Flink, SingleStore, HDFS/S3, and Scala. You will own the full lifecycle of core systems, designing distributed computation and an AI-powered UI/agent framework to deliver intelligent analytics over large-scale business data.

Work with Java 25, Spring Boot, Postgres, and CI/CD practices building REST APIs and microservices. The team develops backend systems for fintech products including card payments, treasury management, and crypto liquidity.