Lead TypeScript and Python development, CI/CD, and API-first design to embed AI into production software platforms. You will modernize legacy systems toward service-based architectures and guide integration with AI services like MCP, working across DevOps, platform engineering, and data science 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.

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

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

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.

You will build and evolve customer-facing interfaces for AI Virtual Agents using React, TypeScript, Next.js and Vite, and refactor the frontend into a scalable platform with a shared component library and design system. Unitary’s factory builds custom operations agents that complete complex workflows end-to-end in customer tools.

Cint★3.5 (13)· London

Use Python and SQL for statistical modeling and machine learning to optimize Cint's programmatic research marketplace (Cint Exchange). You will analyze marketplace dynamics, conduct A/B tests, and build predictive models to guide product and pricing strategy.

Samsara★3.6 (32)· London

Samsara interns work on the Connected Operations Cloud, building backend infrastructure in Golang, web clients with TypeScript/React and GraphQL, mobile with React Native, or embedded software for IoT devices. Projects involve scaling data ingestion, real-time data processing, and creating actionable insights for industries like transportation and agriculture.

Lead Software Engineers at ARQ work with Java 25, Spring Boot, Postgres, TDD, DDD, and CI/CD to build REST APIs and microservices. The team develops fintech systems powering card payments, treasury management, transaction booking, and crypto liquidity.

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.

Senior Software Engineer will work with Java 25, Spring Boot, PostgreSQL, REST APIs, and microservices, using TDD, DDD, and CI/CD. They will build and maintain backend systems for a fintech focused on cross-border money movement, including card payments, treasury, transactions, and crypto liquidity.

Zoopla★3.9 (18)· London

A 12-month maternity cover role on a dual-stack C#, .NET, and TypeScript backend with React microfrontends, using AWS managed services (ECS/Fargate, Lambda, SQS, DynamoDB, DocumentDB) and Terraform/SST. You'll build B2B SaaS software for estate agents and home builders at Alto Software Group. Take end-to-end ownership of features from design to production, working with the product team and AI coding agents.

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.

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.

You'll work primarily with TypeScript, Node.js, and PostgreSQL on GCP, designing and building scalable backend systems. The team develops and maintains a robust investment platform that powers features like mutual funds, bonds, and family investment tools.

DeepL★3.8 (4)· London

You'll work with C# / .NET, RESTful APIs, distributed architectures, and optionally React/TypeScript, plus MCP, CLIs, OAuth, and AI coding tools. You join the API Enterprise team, which builds enterprise adoption features (usage insights, cost controls, RBAC, compliance, data residency) for DeepL's Language AI API platform.

Checkout.com★3.8 (15)· London

Senior Engineering Manager leading the Disputes team, which builds tools, services, and machine learning models to help merchants manage and win chargeback disputes at scale. The team owns a full stack centered on .NET / C#, React and TypeScript front ends, Python-based ML, and event-driven microservice architectures.

Wise★3.5 (42)· London

You will build and refine financial crime prevention systems using Java (or JVM languages) with Spring, React/JavaScript/TypeScript, and CI/CD pipelines, working 80% backend and 20% frontend. You join the Account Integrity team, which protects Wise’s global platform against fraud via machine learning and real-time transaction monitoring, and you will own projects end-to-end.

Wise★3.5 (42)· London

You'll work with Java, Spring Boot, and Kafka on high-concurrency systems. The Assets team scales a "Yield Engine" managing billions in assets; the Investments team builds brokerage infrastructure for individual stock trading and tax-beneficial pots inside Wise.

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.

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.

Robert Half★3.9 (231)· London

Work with React, Next.js, TypeScript, HTML, CSS, and Figma to build pixel-perfect, responsive user interfaces. You’ll join a fast-growing, purpose-driven technology company whose product is trusted by millions, collaborating closely with Product and Design to influence frontend architecture.

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.

You'll work with React and TypeScript to build frontend interfaces for Digital Asset's Financial Engineering team, which designs mission-critical financial workflows like Asset Tokenization and Collateral Management on the Canton Network blockchain. The role involves UI architecture, design systems, performance optimization, and backend integration while collaborating with product and design teams across hybrid locations in Switzerland, UK, Hungary, or Hong Kong.

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.