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).

Monzo★3.5 (108)· London

You will work with LLMs, autonomous agents, RAG, sequence-based architectures, Python, SQL, and Go, developing and deploying machine learning models in production. You’ll lead the design of a human-in-the-loop system that predicts, identifies, and routes customer problems to scale support for Monzo’s banking products across multiple geographies.

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.

BNY★3.5 (5.5k)· London

You'll use Java 17/21 with Spring, Maven, Groovy, JavaScript/TypeScript (Angular), Docker, GitLab CI/CD, IntelliJ, Windsurf, Splunk, and AppDynamics to build secure backend services, batches, and APIs for a global financial services company.

RELX Group★3.8 (133)· London

You will work with Java/J2EE, JavaScript, JSP, C/C++, HTML, XML, SQL, Windows, UNIX, and .Net. The team supports products for education electronic health records that introduce students to digital charting and prepare them for clinical documentation.

Elsevier★3.8 (769)· London

Work with Java/J2EE, JavaScript, JSP, C/C++, HTML, XML, SQL, Windows, UNIX, .Net, and various data storage subsystems. You'll develop complex software solutions supporting educational electronic health record products that prepare students for digital charting in clinical environments.

Quantitative Researchers at Jane Street build models, strategies, and systems for pricing and trading financial instruments, working with Python, petabytes of data, and a large GPU cluster. They apply statistical and ML techniques, from linear models to deep learning.

Design, build and optimise ETL data pipelines using Databricks, PySpark, Python, and SQL for a leading global investment bank. You will work on large-scale enterprise data platforms in a fast-paced financial services environment.

Build enterprise-grade web applications using Python (Django/FastAPI), React, TypeScript, and PostgreSQL. Develop RESTful APIs, responsive UI components, and contribute to system design, CI/CD pipelines, and performance optimization.

Lead design and delivery of web and mobile solutions using AWS, APIs, and modern web development frameworks and languages. This role drives workforce resilience solutions at International SOS, which provides global security risk management and health services.

You’ll work with Python (Django/FastAPI), React, TypeScript, PostgreSQL, REST APIs, and CI/CD. You’ll own end-to-end feature delivery on scalable, enterprise-grade web applications.

Develop core eTrading MI & Analytics platform components using q and kdb+, with CI/CD, TDD/BDD, and an additional programming language. The platform captures, stores, and analyses over 3TB/5 billion daily records from electronic trading venues for risk, quant, trading, and sales stakeholders.

Python micro-services with RabbitMQ and OpenShift/Kubernetes, using SQL Server and Parquet. The London Commodities Risk Technology team builds a front-office distributed platform for trading and risk calculations on assets like oil, gas, power, and exotics, collaborating with traders and quants.

You will work with Python, JavaScript, SQL, Kafka, AWS/Azure, PostgreSQL, SQL Server, ClickHouse, and MongoDB. The team designs and delivers real-time, high-performance trading systems for Energy & Commodities, integrating market data, risk, and front-to-back office workflows.

You will architect Citi's Release on Demand platform, defining architecture, scalability, reliability, observability (tracing, logging, metrics), and E2E testing. The platform codifies governance and automates SDLC deployments for internal engineers. You'll lead a small, agile team distributed across Belfast, Canada, and London, mentoring engineers and owning the technical roadmap.

You will use C/C++, STL, Boost, and Linux to build low-latency algorithmic trading systems. The team develops and supports all aspects of trading strategies, including exchange price feeds, back testing, and production environments for a tech-driven quantitative hedge fund.

You will work with Rust, Java, C++, KDB, event-sourcing microservices, Linux, TCP, and kernel-bypass networking (Solarflare OpenOnload). The High Performance Architectures team builds low-latency application frameworks and supports modernisation for over 100 eTrading teams across Citi.

Build microservices-based event sourcing systems on an in-house low-latency framework using Java, Rust, C++, KDB, and market data technologies within Citi’s London High Performance Architectures team. The team provides application frameworks and modernization support to over 100 teams, with a focus on low-latency algorithmic trading platforms in Markets Technology.

The role involves working with Java (server-side, multithreading), kdb+/q, Python, and CI/CD/testing frameworks. It sits within a specialist team that builds low-latency pricing, eTrading, and eRisk components for Rates and FX products, covering forwards, futures, swaps, bonds, and eCommerce quoting.

Java 11+, Spring Boot, microservices, event-driven architecture, Terraform, and cloud platforms (Azure, AWS, or GCP). The team builds post-trade technology solutions including business-critical applications, APIs, client reporting platforms, and web portals for capital markets. You will mentor developers and contribute to architectural decisions.

Java (JDK 11+), multithreading, SQL/NoSQL databases (Oracle, MySQL, PostgreSQL, MongoDB, Cassandra), message queuing (Kafka, Tibco, Solace), Linux, JVM, and TDD. This tech lead role builds high-performance FX risk calculation systems for Citi’s Markets technology team, which supports global trading and risk management.

Work with Java, GitHub Copilot, Devin.AI, Citi Squad, Stylus Workspaces (Gemini, OpenAI, Claude, Llama), Docker, Kubernetes, and CI/CD. Build high-performance, real-time FX risk management systems for a greenfield platform with a 10+ year strategic commitment. As a VP, lead end-to-end delivery and technical direction.

Work with Microsoft Fabric, Databricks, Azure, Snowflake, Python, Spark, SQL/NoSQL, PowerShell, Azure Data Factory and Azure DevOps to build a Fabric Data Lakehouse for USS’s Investment Management business, implementing scalable ETL/ELT frameworks across a medallion architecture. Share knowledge across a small team of data engineers and collaborate with architects, business stakeholders and data teams.