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

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.

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.

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.

Build a production platform using FastAPI, React, GCP, PostgreSQL, Docker, Terraform, and Redis, developing agentic AI systems and evaluations for automated cyberattack investigations. You'll own reliability end-to-end, including CI/CD, SLOs, and incident response. This is a founding role at an AI-native Digital Forensics and Incident Response startup.

You'll work with AI-assisted development tools like Claude Code, LLMs, RAG, agentic tooling, and own the full stack: React/Angular, Python, AWS/Terraform. Embedded with Product and Engineering teams, you'll design and build bespoke AI solutions for customers at a hypergrowth SaaS scaleup, turning their workflows into reusable, production features.

You will work with Python, TypeScript, LLMs, agentic workflows, Claude, Claude Code, MCP, and APIs. The company’s live AI product is a step change for a UK industry; you’ll build systems that power the commercial team’s sales and marketing automation. This is an early-stage AI-native startup with a revenue-generating product and an enterprise pilot.

Senior Frontend Engineer working with JavaScript, React, Vue, and TypeScript on a HealthTech product for the care industry. The team of 10 builds software used within the NHS to assist doctors and nurses.

Houseful★0.0· London

A 12-month fullstack engineering cover role using TypeScript, C#, .NET, Node.js, and React on AWS (ECS/Fargate, Lambda, SQS, DynamoDB, DocumentDB) with Terraform. You will build microservices and microfrontends for a B2B SaaS platform powering UK housing transactions. You will also use AI coding agents and own features from prototype to production.

Build React Native identity-verification and onboarding experiences using JavaScript/TypeScript, component architecture, state management, and CI/CD pipelines. The identity engineering team owns the customer-facing front door of Zepz’s cross-border remittance platform, handling millions of users’ first contact and security checks.

You will work with React and MUI to design and implement interfaces for visualizing attack chains and hierarchical vulnerability data. As the founding design hire, you’ll build the intelligence layer for cybersecurity, turning complex vulnerability data into intuitive threat models for a well-funded cybersecurity AI startup.

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.

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.

Senior C# .NET developer role on the Data team of a global energy trading house, building data platforms for market data collection, real-time streaming, governance, and machine learning, with a focus on data consumption and publishing. Tech stack includes C#, .NET, ASP.NET, Angular, SQL Server/Oracle, Docker, Kafka, Azure Service Bus, Grafana, and Azure DevOps.

Build a high-scale SaaS platform using Rust on the backend and React/TypeScript on the frontend, hosted on Google Cloud. Platformed Ltd automates audit and control assurance workflows for enterprise clients. As the seventh engineering hire, you will own features end-to-end, from architecture to deployment.

Build and iterate on full-stack product surfaces and core infrastructure using modern AI tools, LLM orchestration, and multi-step reasoning systems. You will work directly with founders at a stealth-stage fintech that builds an AI-native observation layer for institutional investors.

Lead a software team building MasterBuilder, a platform orchestrating robotic home construction using Node.js, TypeScript, React, and Three.js. The company automates homebuilding via robotic MicroFactories that produce timber structures on-demand.

You will own back-end infrastructure and data strategy, building scalable GCP pipelines, designing high-performance APIs with Python and FastAPI, and developing full-stack features with automated CI/CD. The company, an Imperial College spin-out, produces advanced gas sensors and AI that predict food freshness in real-time to replace printed expiry dates across global supply chains.

You will build and ship polished, full-stack features using AI tools to accelerate development, owning the entire product lifecycle from customer interviews to deployment. You will join an 8-person team at Romeai, a London startup creating an AI-driven real-time system of record for global supply chains.

You’ll build the automated outbound engine from zero to one, owning CRM workflows, data enrichment pipelines, and sequencing, using Python, SQL, JavaScript, and modern AI tools. This founding role drives global revenue growth for a VC-backed AI proptech startup, deploying AI agents to real estate decision-makers.

Work with Core Java, ReactJS, Kafka, Kubernetes, AWS, Spring Boot, RESTful APIs, gRPC, and Redux. Design, develop, and maintain scalable cloud-native applications for investment banking and risk management. No team size stated.

Flock★4.0 (6)via Jack & Jill· London

You will work with TypeScript, Node.js, PostgreSQL, and a modern AWS serverless stack including Lambda, SQS, and EventBridge, using Terraform or CDK for infrastructure. You will lead the Retain team in designing and operating full-stack services that embed Flock’s fleet-insurance product into the daily workflows of fleet owners.