You will build and maintain robust data infrastructure at a financial technology company, supporting international applications and cutting-edge AI/ML experiences. Your work ensures seamless platform operation at scale.

You will work with backend development, databases, APIs, cloud services and production machine learning systems. This is for a growing technology business. No specific project or team size is mentioned.

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.

Monzo★3.5 (108)· London

You will build and deploy deep learning, graph-based, and sequence-based ML models using Python and SQL, with exposure to Go. You will design human-in-the-loop systems and autonomous agents to route, prioritise, and automate customer-support issues for millions of customers across thousands of support staff at Monzo. You will be one of four ML engineers embedded in product squads.

You will work with Python, AI coding agents (e.g., Claude Code, Codex), and potentially AWS, Kubernetes, and Temporal. Unitary builds Virtual Agents — AI-powered software workers that automate complex workflows end-to-end in customer tools, focusing on commercial insurance, marketplaces, and primary healthcare.

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.

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 will develop and iterate on polymer blends and additive packages using characterization tools such as DSC, TGA, and rheometry. You’ll join a climate tech team creating high-performance, compostable plastic alternatives, bridging lab characterization and industrial scale-up. The startup is well-funded at Series A, backed by leading impact investors.

You'll work with time-series data, supervised and unsupervised ML, CI/CD, version control, and tools like Claude Code, MLflow, and cloud platforms (Azure, AWS, GCP) with MongoDB. Ceto provides operational intelligence for maritime, analyzing ship data to predict mechanical failures through anomaly detection and degradation forecasting.

You will work with Python, LangGraph, CrewAI, OpenAI/Claude Agent SDKs, AWS Bedrock, ECS Fargate, Lambda, Step Functions, and LLMs like GPT, Claude, and Perplexity. You will design and evolve multi-agent systems and LLM pipelines powering a production-grade AI-powered brand analytics platform that helps businesses understand market positioning.

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.

You will build multi-agent AI systems using LangGraph, Neo4j knowledge graphs, FastAPI, and Google Cloud Platform. The role focuses on architecting and scaling AI-native software for tax advisory teams at a seed-stage London startup.

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.

Google★4.3 (6.2k)· London

You'll develop in C++, Python, or Rust, building the Google Cloud Universal Ledger (GCUL), a cutting-edge payments platform addressing cost, speed, and fragmentation in financial systems. You'll implement low-latency features, including cryptography like homomorphic encryption and zero-knowledge proofs, while owning code for consensus, transaction dissemination, and finalisation.

Hudson River Trading★4.5 (2)· London

You will work with Python, Pandas, NumPy, R, and MATLAB to apply statistical analysis and machine learning to vast quantities of market data. The team builds and maintains predictive trading models for the company's high-performance trading infrastructure. You will research, develop, and test order execution methods to increase trading efficiency.

Hudson River Trading★4.5 (2)· London

Software engineering interns work with Python, C, or C++ on independent programming projects and gain hands-on exposure to HRT's algorithmic trading research and infrastructure.

Hudson River Trading★4.5 (2)· London

You will use Python, C++, Pandas, NumPy, R, or MATLAB to build and maintain predictive trading models. As an algorithm developer, you research and test novel order execution and model training methods, applying

Hudson River Trading★4.5 (2)· London

You will write and maintain critical trading infrastructure using C/C++ or Python on Linux, working closely with engineers who design trading algorithms in a fast-paced, real-time environment. The role is with Hudson River Trading, a firm that brings a scientific approach to trading financial products.

You will use TensorFlow or PyTorch, Python, and CV/graphics libraries, plus 3D engines like Unreal or Unity, to develop generative models for graphics and video. As part of the Visual Computing Group, you'll design neural networks and ML for PlayStation's game rendering and live

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.

As the first software hire, you will build the entire cloud and platform layer, working with connected hardware, real-time data, and external energy markets. NODI Energy is a YC-backed startup orchestrating plug-in batteries as a flexible power fleet to cut grid congestion and free up capacity for data centres.

Build and scale Nxera Pharma’s computational drug discovery platform, working with Python, AWS, Docker, Prefect, GitHub Actions, Terraform/CDK, PostgreSQL, and Linux. You'll develop backend services, cloud infrastructure, CI/CD pipelines, and workflow orchestration alongside computational chemists and ML engineers. No team size is stated.