Post-train, fine-tune, and distil frontier language models using RL, distillation, and reward design in Python. Build production-grade simulation systems that model thousands of individuals in real-time for a Societal World Model at a YC-backed startup.

You’ll work with Python, FastAPI, TypeScript, React, and GCP. Electric Twin builds a behavioral simulation platform that creates “digital twins” of real populations, helping organizations test decisions with 95% accuracy.

You'll work with Python (FastAPI/Django), Svelte/TypeScript, and AWS to build features across a payments and discovery platform. Tab is a YC-backed travel fintech enabling 100,000+ global tourism businesses to accept payments in 100+ currencies.

Allianz★3.8 (3.4k)· London

You'll build production data/ML systems using Python, Docker, Kubernetes, Terraform, Azure, Azure DevOps or GitHub Actions, plus SQL, PySpark, dbt, and Microsoft Fabric. Joining a small agile team, you'll deliver real-time API endpoints serving 10M+ daily requests and evolve cloud infrastructure and

Build and scale distributed infrastructure on AWS using Pulumi for high-performance AI model inference. Develop end-to-end features across TypeScript/React frontends and Python-based agents for automating complex workflows in aerospace and healthcare.

You will work with Python, PyTorch or JAX, Docker, CI/CD, and cloud platforms to deploy ML models for protein design. The team builds scalable infrastructure for training, inference, and evaluation across molecular and protein datasets, taking research prototypes into production.

You will build and optimize multi-agent AI systems using Python and LLM orchestration tools like Temporal or LangChain, plus observability and data pipelines. Tuza is a London fintech creating AI agents that automate manual banking workflows for partners like Worldpay and NatWest.

You will work with C#, Python, TypeScript, JavaScript, React Native, AWS or Azure, and various databases (relational, graph, document, key-value) plus SQL. The role supports critical projects aligned with Net Zero ambitions.

You will work with Java, Spring Boot, microservices, REST APIs, AWS, DevOps and CI/CD pipelines. You’ll lead client projects for a global technology consultancy, mainly in financial services, focusing on migrating legacy systems to AWS and introducing cloud deployments. As Principal Java Developer, you will lead projects, but team size isn’t specified.

Build UI components using Vue.js, React, or Angular, plus JavaScript, HTML/CSS, and Figma. You'll join TransPerfect TechOps, which develops workflow improvements, core services for the GlobalLink platform, and scalable client interfaces. Work within an Agile (SCRUM/Kanban) team.

NatWest Group★3.7 (1.2k)· London

Leading a team building cloud-hosted, event-driven microservices at NatWest Boxed, you will manage software and quality engineers across empowered squads while working with AWS, Google Cloud Platform, Java, Python, JavaScript, ReactJS, AngularJS, Kafka, Hadoop, PostgreSQL, Snowflake, and GitLab.

Morningstar★3.9 (185)· London

Work with Python, R, MATLAB, SQL, statistical and machine learning techniques, and AI. Build thematic and smart beta indexes for Morningstar’s Indexes New Product Development team, covering the full lifecycle from ideation to launch.

SS&C★3.2 (1.7k)· London

Design, develop, and maintain automated test suites using C#, BDD frameworks (SpecFlow/Reqnroll), GitHub Actions, Playwright, and Selenium WebDriver. You will integrate AI-powered tools like Claude Code and GitHub Copilot to accelerate testing across Calastone's financial products, a global funds network.

You will work with agentic LLMs, reinforcement learning, Python, PyTorch, JAX, HF, and tools like CleanRL/AutoGen/LangGraph on an agentic code generation tool. The team designs multi-agent and RL approaches, builds research prototypes, creates evaluation suites, and curates datasets from complex technical documents.

In this Senior Data Engineer role on the Scalable Growth team, you will work with Python, dbt, Airflow, Kafka, Trino, and Iceberg to build high-volume streaming and batch data pipelines. The Marketing Platform team owns the data infrastructure, internal tools, and third-party integrations (e.g., Meta, Google) that power Wise’s global customer acquisition channels.

Allianz★3.8 (3.4k)· London

Use Docker, Kubernetes, Terraform, Azure, Azure DevOps, and Python to build and maintain production-ready data and ML systems, including real‑time API endpoints serving 10M+ daily requests. You will join a small stream‑aligned agile team that develops cloud‑based infrastructure and automated deployment pipelines.

Atlassian★3.9 (61)· London

Leads a team of forward-deployed engineers building AI-powered solutions with Python, JavaScript, APIs, microservices, and LLMs. The team partners directly with top organizations to apply Atlassian’s AI capabilities to solve real-world problems.

EXL Service★3.7 (2k)· London

You will work with Generative AI tools (OpenAI, LangChain, Hugging Face, Vertex AI, Bedrock), LLMs, vector databases (FAISS, Pinecone, ChromaDB), and Python frameworks (Transformers, PyTorch, scikit-learn). As part of EXL’s Data Science Team, you’ll build and deploy GenAI solutions for enterprise use cases such as customer service, document automation, summarization, and knowledge retrieval.

Work with Python, large language models, AWS services, Claude, Docker, and Linux to build AI agents and cloud solutions. You'll join Cloudscaler, a consultancy delivering AWS transformations for government, defence, and enterprise clients. This graduate entry role starts in a cohort with structured mentoring and certification support.

HCLTech★3.7 (11k)· London

You will work with Python, Go or Java, TypeScript, REST/gRPC, Gemini 3.0, Vertex AI, BigQuery, Vector Search, AlloyDB, Apache Beam/Dataflow, Agent Development Kit, LangGraph, and GKE. The role deploys Gemini Enterprise Agent Platform, designs multi-agent systems, and builds RAG pipelines to integrate with legacy APIs and ERP systems. Clients are in FS, RCPG, LSH, and manufacturing domains.

EPAM Systems★3.8 (703)· London

You will lead the design and optimization of scalable cloud-native data architectures using Azure Databricks, PySpark, Delta Lake, and Delta Live Tables, with Azure-native services like Data Factory and Synapse, plus CI/CD tools (Terraform, GitHub Actions). The team builds large-scale data platforms and ETL/streaming pipelines following Lakehouse principles, driving modernization and AI initiatives. As tech lead, you mentor engineers and define data strategies.

Sonar★5.0 (2)· London

You will work with Python, core ML frameworks, and post-training techniques including GRPO, PPO, RLVR, SFT, PEFT, and preference/safety alignment (Rust or SonarQube flagship languages are a plus). You will join a cross-disciplinary team developing advanced products that post-train models to power enterprise agentic coding practices, ensuring code meets enterprise standards.

You’ll work with JavaScript, TypeScript, React, Next.js, Node.js, Python, WebGL, Three.js, Unity, Unreal Engine, TouchDesigner, LLMs, AI agents, ComfyUI, vector databases, AWS/GCP/Azure, and Figma. At WPP Production, a global content production company, you’ll rapidly prototype and scale interactive digital experiences, bridging software engineering and creative design. You will line-manage and mentor mid-level and junior developers.

You will work with SQL, BigQuery, dbt, and A/B experimentation. As part of the data team at Muzz—the world’s biggest dating and marriage app for Muslims—you will analyse user behaviour, own reporting dashboards, and provide analytical support across the product development lifecycle.

Verisk★3.5 (361)· London

Use TypeScript, JavaScript, Angular, Node.js, Azure or AWS, and microservices to design and build large-scale, cloud-native software solutions for Verisk’s insurance analytics platforms. You will shape technical architecture across multiple products and teams.