You will work with C++, Python, Linux, machine learning/statistical libraries, Google Cloud, Airflow, InfluxDB, and Grafana. The role builds data pipelines, prediction tools, and infrastructure for systematic equities trading, supporting quantitative research and large-scale computation.

This role supports eTrading platforms using Windows/Linux, Bash, PowerShell, Python,

You’ll develop components for a research and trading platform used by quant researchers and portfolio managers, working in Python and relational databases with optional AWS/GCP, CI/CD, and containerized environments. The team builds scalable backtesting tools, data pipelines, and production-grade research infrastructure. This is a Python developer role; no team size is stated.

You will develop predictive signals and systematic HFT and market-making strategies using order book dynamics, trade flow, and large datasets with Python. The proprietary firm trades its own capital in high-frequency cryptocurrency markets. You will own the complete research lifecycle, from hypothesis through live production and performance optimisation.

You'll work with Microsoft 365, Power Platform, Python, PowerShell, and various SaaS tools and integrations. As a Business Systems Engineer at a technology consultancy, you'll support users building applications and automations, troubleshoot low-code platforms, and improve governance of internally developed tools.

Quantitative researcher role using Python or C++ to develop signals, models, and trading strategies for global financial markets, plus research tools and data pipelines evaluated with advanced statistical techniques. Works with a small team of researchers and engineers on systematic trading research infrastructure. Candidates need a PhD or postdoc in a quantitative field.

Work with Python, PyTorch, TensorFlow, Scikit-learn, XGBoost, AWS (SageMaker, Lambda, S3), MLflow, LangChain and other MLOps/LLMOps frameworks to build and deploy ML and generative AI solutions. You will design production-ready models for forecasting, classification, and anomaly detection, as well as LLM-powered applications, supporting defence, government, and national security clients as part of a technology consultancy.

This Full Stack Engineering Lead role at Citi’s Finance Technology team involves hands-on development with Java, Spring Boot, Spring Cloud, React, TypeScript, Node.js, and microservices. The team is re-platforming applications to support the Finance business, focusing on building scalable solutions for regulatory and operational needs. Testing practices use Jest, Cypress, JUnit, and Mockito, with AWS or GCP experience as a plus.

Python and C++ for building real-time market-data systems, cloud-based simulation platforms and production-deployment toolchains. This engineer designs infrastructure that lets quantitative researchers develop, test and execute predictive models at a systematic-investment firm currently spinning out from a hedge fund to become an independent manager.

React Native developer will work with JavaScript/TypeScript, APIs, and CI/CD to build and optimise mobile apps for iOS and Android. The role is with a FinTech undergoing a digital transformation programme, modernising core mobile products and improving user journeys.

Work with Microsoft Copilot Studio, Python, Azure, APIs, AI agents, LLMs, and generative AI to build AI-powered tools, automation workflows, and scalable solutions deployed into live business environments within a growing AI and Automation function.

Senior Software Engineer for pricing and availability systems on a global travel and e-commerce platform, using TypeScript, Node.js, C#/.NET or Python, and SQL. Work involves building pricing, quote-caching and availability services, resilient APIs, and improving performance and observability with tools like Datadog and Terraform.

Senior Kotlin backend role with full-stack exposure to Angular/React, Spring AI, reactive streams, and event-driven tools like Kafka or RabbitMQ. You'll build a data integration platform for banks, an open-source schema language, and a greenfield AI agent for autonomous orchestration.

Work with AI/ML systems, prompt engineering, multimodal models, retrieval systems, agent systems, computer vision, and backend services using Go, Python, or C. You will join a small R&D team building a cloud platform that transforms audio and video data into actionable intelligence for commercial clients.

You will work with SQL, Python, DBT, Fivetran, Airflow, Snowflake, Git, and cloud platforms (AWS, Azure, or GCP). The role designs, builds, and maintains scalable data platforms and pipelines that power analytics, reporting, and data-driven decision-making. No team size is stated.

You will architect low-latency inference pipelines for multimodal LLMs, TTS, and Vision models using C/C++, Python, PyTorch or JAX, and optimize them with custom CUDA/Triton kernels, TensorRT, and ONNX. The team at this seed-stage AI-native game studio builds intelligent virtual actors that speak, move, and react in real-time for interactive entertainment.

Work with Python, AWS, and Kubernetes to build and maintain custom integrations, API fixes, and SDKs for a voice AI startup. You will support the Forward Deployed Engineering team, managing one-off integrations, platform fixes, and custom builds for enterprise clients deploying large-scale voice infrastructure.

Build features across a Svelte/TypeScript front end and Python back end using FastAPI, Django, PostgreSQL, and AWS. Tab is a YC-backed London travel fintech processing thousands of real-time payments per hour for over 100,000 global tourism businesses in 100+ currencies.

You will work with Python, post-training language models (RL, distillation), and build data pipelines and inference infrastructure. The company is building a Societal World Model to simulate human opinion and influence, enabling Fortune 500 organizations to test strategies against simulated populations.

Use Python (FastAPI/Django) and Svelte with TypeScript to build and scale a payments platform processing 100 currencies and a discovery engine listing 100,000+ tourism businesses. Work on AWS cloud infrastructure and real-time transaction processing as part of a profitable, lean team of nine.

Work with Python or Node on backend distributed systems and serverless architectures on AWS, with a smart contract language such as Solidity. The company builds services to accept card payments and grow businesses globally. No team scope is specified.

Senior Machine Learning Engineer working with C++, CUDA, Python, and PyTorch. The role is within an AI technology company developing next-generation machine learning solutions for complex real-world applications.

Harvey Nash★3.8 (49)· London

You will build enterprise-scale applications using Java, Spring Boot, microservices, and front-end technologies (likely React or Angular), with exposure to AI tools and modern DevOps practices. You will join a high-performing engineering team at Harvey Nash, developing large-scale software solutions in a hybrid London-based setting.