You will work with Rust or Python to build core infrastructure for Indices, a startup creating network-level tools that let AI agents reliably and securely programmatically navigate any website. Your work will include designing hardened sandboxed runtimes, building CLI tools and telemetry systems, and owning features end-to-end in a high-agency, systems-focused environment.

Sony Music Entertainment★4.2 (454)· London

Use Python, JavaScript/TypeScript, React, GraphQL, REST APIs, SQL/NoSQL databases, and AWS Cloud. Build products for Sony Music's PDEGO team that empower artists and record labels globally. Work with distributed systems, microservices, and

You'll work with Java 17+, Python, Spring Boot, Oracle SQL, document-store DBs, Kubernetes, Jenkins, and GitHub Copilot. The team builds mission-critical systems providing end-to-end visibility into payment lifecycles for an investment bank. You will mentor junior engineers and lead code reviews.

Founding ML Engineer role at an early-stage consumer health-tech startup building systems for chronic disease management. You will own the technical stack end-to-end, working with Python, Bayesian/probabilistic modelling, NLP/LLM tooling, knowledge graphs, and causal inference methods. The 12-month fixed-term position involves co-designing a domain ontology and building extraction pipelines with human-in-the-loop validation, with a path to CTO.

You will work with the Hivemind Enterprise Autonomy SDK, writing modern C++ and intermediate Python to develop AI and autonomy applications for unmanned platforms across air, sea, land, and space. You will deploy Hivemind AI infrastructure at customer sites, integrate autonomy into vehicles, debug API issues, and provide technical training. You join Shield AI, a defense-tech company building autonomy software and aircraft, supporting operations worldwide.

You'll work with Python, TypeScript, AWS, PostgreSQL, and event-driven architectures building real-time software for energy trading and grid optimization. This early-stage climate tech startup is building a new platform from scratch, and as part of a small engineering team you'll own backend services, APIs, and product features end-to-end.

Work with Python (C++, Rust, or Go for latency-critical paths), AWS, Terraform, PostgreSQL/TimescaleDB, Kafka, Redis, ClickHouse, and Grafana/Prometheus/Loki. You own the production infrastructure for a stealth systematic trading and AI research lab building low-latency decision engines that operate in live markets.

LMAX Group★0.0· London

Develop high-performance data pipelines and real-time streaming systems using Python, Terraform, Ansible, Kubernetes, Kafka, and SQL. You will build and scale data infrastructure to support business intelligence initiatives for LMAX's Forex and digital currency trading platforms.

You will use .NET C#, LINQ, MS SQL, Entity Framework, GIT, REST APIs, Docker, and Agile methodologies to design, build, and debug web and mobile applications. You will join the TransPerfect TechOps team, which delivers the company's GlobalLink platform and related client interfaces.

S&P Global★3.9 (1.7k)· London

Work with SQL for querying, validating, and analyzing data; Python or a complementary language; cloud-based infrastructure (preferably Databricks); and data visualization tools like Power BI or Tableau. You will develop scripts and automation to validate data, resolve discrepancies, and improve data quality for the Ratings Data Center of Excellence at S&P Global Ratings.

Allwyn UK★3.4 (8)· London

This role delivers security testing across web applications, REST APIs, backend services, cloud-hosted workloads (AWS and Azure), and internal infrastructure using tools like Burp Suite, Kali Linux, Nmap, Nessus, and Wireshark. The position supports Allwyn UK's transformation of The National Lottery to increase funds for good causes.

Allwyn UK★3.4 (8)· London

You will conduct hands-on security testing across web applications, REST APIs, backend services, AWS and Azure cloud platforms, and internal infrastructure using Burp Suite, Kali Linux, Nmap, Nessus and Wireshark. Your work supports Allwyn UK’s National Lottery, ensuring vulnerabilities in its applications and cloud-hosted workloads are identified, validated, remediated and retested. This role sits within a team delivering security testing for a high-availability, transaction-critical national lottery system.

You will work with Rust, Python, Java, Go, C++, and a distributed systems stack involving edge computing, low-bandwidth radio links, and air-gapped networks. This company builds AI software that turns unstructured sensor data into real-time intelligence for semi-autonomous platforms. You will set technical direction across multiple teams.

You'll work with TypeScript, Python, Playwright, Cypress, WebdriverIO, Node.js, Docker, and GitHub Actions/GitLab CI to build and maintain test automation frameworks and CI pipelines for Connected TV devices. You'll join FX Digital's Quality Engineering team, taking ownership of automation platform pieces and mentoring junior engineers—no prior TV experience required.

Meta★4.0 (1.1k)· London

Business Support Engineer supporting Meta's Business Agent, an AI platform helping businesses boost productivity. Work with Python, PHP/Hack, JavaScript/React, REST APIs, SQL, PyTorch, Llama and other LLMs, plus cloud infrastructure (Kubernetes, Docker). Provide engineering support, troubleshoot distributed systems, and build AI solutions from prototype to production.

You'll work with Java, Python, JavaScript and Agile methods to design, build and test software. The Engineering Platforms team delivers a modern software development tools chain for engineers across NatWest Group.

You'll work with React, TypeScript, and Python (or Node.js) to build AI-driven matchmaking systems connecting pharma with medical experts. The platform processes 9M+ clinician profiles and billions of records, automating healthcare commercialization workflows for global drug development at G LNK (YC W25).

Houseful★0.0· London

You will work with Databricks, DBT, Fivetran, Python, SQL, AWS (EventBridge, Kinesis, Lambda, S3, EC2), Terraform, Kafka, ECS, and Kubernetes. You will scale the data lakehouse powering analytics and AI, build infrastructure for data commercialisation products, and create reusable building blocks for engineering teams.

Work with Snowflake data architecture, SQL, Python pipelines, RESTful APIs, the Microsoft Power Platform, React front ends, and, optionally, ServiceNow, Workday, and Azure services. The Data and Applications team builds analytics, AI-powered tools, and data infrastructure for PJT Partners, a global advisory-focused investment bank.

Rippling★0.0 (17)· London

You'll develop Rippling's full-service payroll platform handling configuration and calculations for hundreds of thousands of employees, using Python, Django, and React. The role involves owning product initiatives from conception through scaling, mentoring engineers, and maintaining platform reliability. You'll partner with design and product leadership to shape the payroll team's vision while driving engineering excellence across the organization.

You will work with Rust, C, C++, Go, CUDA, Triton, CUTLASS, PTX/SASS, MLIR/LLVM, and applied cryptography for

Build backend databases in SQL Server and Azure, build machine-learning models in Azure, Microsoft Fabric and Alteryx, and develop front-end apps using Python, SQL, C#/.NET and JavaScript for the SMDAM Private Markets team. The role drives private credit data infrastructure end-to-end, extracting insights from text to power deal-sourcing and monitoring across the entire private credit lifecycle.

Work with AWS, Docker, Kubernetes, CI/CD pipelines, infrastructure-as-code, and Python/Go/Ruby/JavaScript. You will support Digital Engagement products and help build the AI Platform at SBS, a global fintech partner for banks and financial institutions.

You will work with Java, SpringBoot microservices, Linux, OpenShift, Gradle, Git, CI/CD, and Docker/Podman. The Technology Application Strategy team builds productivity and tooling solutions to streamline workflows for Citi’s global developer community.

You will use Python, REST APIs, and cloud platforms such as AWS, Kubernetes, Docker, and Helm. As part of the Risk team at a tech-driven quantitative investment manager, you will build and deliver solutions for Risk Management and Trading desks.