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.

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 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.

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.

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.

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).

Lovable★4.0 (43)· London

Uses Go, Rust, TypeScript; AWS, Azure, Google Cloud, Cloudflare; Kubernetes, Terraform, Temporal, OTEL, CI/CD; PostgreSQL, ClickHouse, Firestore, Spanner, BigQuery. Builds the platform for Lovable Enterprise enabling secure, cloud-agnostic deployment, defining architecture for sandboxing, networking, encryption, identity, and mentoring engineers.

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.

Work with Java, Python, JavaScript/TypeScript, Go, cloud platforms (AWS, Azure, GCP), CI/CD pipelines, and version control. Guiding the technical direction of BabuSpace’s premium short-term rental marketplace platform for African cities, designing backend architectures, and mentoring engineers.

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 and Spring Boot, React, AWS, and CI/CD pipelines are the primary technologies. You will build microservices-based customer-facing applications for a leading retail bank’s cloud-native digital banking platform. No team size is stated.

Work with Kotlin, Java, Spring Boot, microservices, REST APIs, Node.js, TypeScript, Express.js, Nunjucks, AWS/Azure/GCP, Docker, Kubernetes, Terraform, and CI/CD tools. You'll build secure, scalable digital services on large-scale transformation programmes for the Public Sector and Healthcare within Agile, multidisciplinary teams. Mentoring other engineers is expected.

Full Stack Developer role at a specialist investment business. You'll use TypeScript, JavaScript, Python, React, Next.js, Node.js, RESTful APIs, relational/NoSQL databases, Azure, Git, and CI/CD to build and evolve the technology platform with the existing team and senior stakeholders.

You'll work with Kotlin, Java, Spring Boot, microservices, REST APIs, and cloud platforms (AWS, Azure, GCP) alongside Docker, Kubernetes, and CI/CD pipelines. As part of a digital consultancy, you'll build secure, scalable cloud-native solutions for public and private sector clients.

The role involves Java backend, SQL, database design, REST APIs, event-driven architectures, and Angular or a similar front-end framework, with system integration and distributed systems. No specific product, project, or team size is mentioned in the listing.

Java Developer role using Java, RESTful APIs, microservices, PostgreSQL, Oracle DB, SQL, Kubernetes, AWS, and monitoring tools. The developer builds and maintains backend APIs, new services, and database integrations, collaborating with product, DevOps, and QA teams. Requires at least 3 years of Java experience and Chinese language proficiency.

Koinly★3.0 (1)· London

You will work with TypeScript on Bun, RabbitMQ, Redis, PostgreSQL, Vitest, Sentry, and Rust. The team owns the distributed data-processing backend that ingests, normalizes, and reconciles on-chain and exchange data for Koinly’s crypto tax calculation product.

You'll work with frontend (TypeScript, React, Angular, Vue, Next.js, Tailwind), backend (Python, Node.js, Java/Spring, C#/.NET), databases (SQL, NoSQL, vector databases), LLM frameworks, and cloud platforms (Azure, AWS, GCP) including Docker and CI/CD. QuantumBlack, an AI division of McKinsey, builds industry-shaping products and tools across diverse industries by pairing software engineers, AI engineers, and data scientists with client leadership. As a Senior Software Engineer, you'll lead architecture design, mentor teams in engineering excellence and Agile practices, and drive technology decisions on scalable solutions.

Spotify★4.1 (116)· London

You will work with React, TypeScript, Java, GraphQL, PostgreSQL, and Google Kubernetes Engine (GKE) to build end-to-end solutions. The team builds Groove, a platform that helps thousands of employees plan, coordinate, and deliver work across Spotify.

Build with Python, Go, or Java on the backend, and React/TypeScript on the frontend, using PostgreSQL and non-relational stores, with Docker, Kubernetes, and cloud infrastructure (AWS, GCP, Azure). This role owns full-stack delivery of the B2B product—a campaign, device management, and insights platform for retail and brand partners—along with API design and distributed systems. The team includes engineers, product, and platform groups, working closely with the Head of B2B Product.

JPMorgan★3.9 (20k)· London

Lead projects on the Strategic Index Technology team, using Python, Java, C++, or C# to build and maintain the cross-markets index platform alongside Quantitative Research, Trading, and Sales.