Python LLM Engineer at Caxton Associates | London

Role overview Genomics England is looking for a Software Engineer with solid Python experience to help create software that drives genomics research and benefits patient care. The team combines engineers and scientists who work together to build scalable tools that advance the organization's mission. What you will do Develop and maintain software applications using Python for genomics-related projects. Collaborate with fellow engineers and scientists to design solutions that back both research and clinical goals. Contribute to technology projects aimed at improving patient outcomes. Location This role is based in London.

As the Chief of Staff at Genomics England, you will play a pivotal role in shaping and executing strategic initiatives across our organization. You will collaborate closely with senior leadership, ensuring alignment of our goals and objectives while driving operational excellence. Your expertise will be crucial in optimizing workflows and fostering a culture of innovation and accountability. This position offers a unique opportunity to influence the future of genomics in healthcare.

Join Genomics England as a Genomic Data Scientist and make a significant impact in the field of rare diseases. You will be part of a dedicated team focused on leveraging genomic data to improve patient outcomes. In this role, you will analyze complex datasets, develop predictive models, and collaborate with multidisciplinary teams to drive innovation in genomic research.

Role OverviewWe are seeking a talented Software Engineer specializing in Python to join our team at cfpenergy. In this pivotal role, you will be instrumental in designing, developing, and scaling our data infrastructure, which is crucial for driving our products and informed decision-making processes. You will help define the flow of data throughout the organization, ensuring it is efficiently ingested, processed, and transformed into actionable insights. Collaborating with developers, analysts, and trading teams, you will ensure our data is not only reliable and accessible but also future-proof. This position seamlessly blends hands-on engineering with architectural insight, allowing you to participate in design discussions, enhance data pipelines, and guide our technical strategy. We are looking for someone who takes initiative, relishes solving intricate problems, and can work collaboratively across various systems and teams to create meaningful impact.Key ResponsibilitiesArchitect, develop, and uphold robust applications within a domain-driven ecosystem.Engage in architectural dialogues and influence the long-term technical strategy.Manage tasks from requirements gathering to completion, showcasing creativity and adhering to coding standards.Create well-structured data models and maintain comprehensive documentation in collaboration with your team’s data engineers.Work closely with data engineers, developers, analysts, and trading teams to gather requirements and deliver dependable, well-architected data solutions.Identify and implement enhancements to performance, automation of manual tasks, and improvements in data quality and reliability across systems.Core Skills & ExperiencesCollaborative mindset: We seek individuals who are not only adept but also enjoyable to collaborate with, promoting a positive team culture through open communication.Analytical thinking: Accuracy and performance are central to our operations; your curiosity, structured approach, and meticulous attention to detail will drive every challenge.Problem-solving skills: You should be comfortable navigating complex systems to diagnose root causes while maintaining composure under pressure, striving for elegant, sustainable solutions.Effective communication: Your ability to articulate complex technical concepts clearly will bridge the gap between technical and non-technical teams, ensuring alignment.

About the PositionAt Jane Street, we are constantly on the lookout for talented software engineers across all our offices. Technology lies at the heart of our operations, and our engineers play a crucial role in every facet of our business.We embrace functional programming, utilizing OCaml—a statically typed functional programming language—as our primary tool. Recently, Python has also become integral to our research and trading processes, serving as the preferred language for data analysis, visualization, and machine learning.We are strong advocates for open-source software, actively employing it in our daily tasks and contributing over a million lines of our own code to the open-source community.About YouExceptional programming skillsA profound passion for technology. While there is no specific checklist, we utilize software to tackle diverse challenges, so we welcome experience spanning machine learning, systems administration, and programming language design.Excellent interpersonal skills. Software engineering at Jane Street is highly collaborative, and we seek individuals who thrive in small, close-knit teams.No prior experience in functional programming, OCaml, Python, or finance is required; we are eager to hire talented engineers and provide the necessary training.Fluency in English is mandatory.To learn more about our software engineering interview process, visit our interview prep page.

About AboundAt abound, we are revolutionizing the landscape of consumer lending across the UK and beyond. By leveraging cutting-edge AI and Open Banking data, we strive to make fair and affordable personal finance accessible to a wider audience. Unlike traditional lenders who heavily depend on credit scores, we analyze the complete financial picture of our customers—considering their spending patterns and repayment capabilities—to build a nuanced understanding of their unique financial situations.Our approach has proven successful at scale. We have facilitated over £1.3 billion in loans directly to customers while achieving exceptional credit performance—for every 10 defaults anticipated by the industry, we experience only 3. Remarkably, we reached profitability just 2.5 years post-launch.With backing from over £2 billion from prestigious investors including Citi, GSR Ventures, and Deutsche Bank, we are recognized as one of Europe’s fastest-growing fintech companies (Sifted, CNBC). As we expand into new markets and product lines, we are on the lookout for driven individuals eager to learn, take ownership, and grow alongside us.We are seeking a talented Senior Python Engineer to join our engineering team. In this role, you will collaborate closely with our Finance team to design and implement automation solutions that enhance our core financial operations. You will be responsible for translating business needs into robust, maintainable systems that increase accuracy and efficiency across critical workflows.This position requires a candidate who blends strong technical acumen with a desire to understand the business intricacies. You will be empowered to independently scope and execute changes, manage stakeholder expectations, and ensure every enhancement is durable. Your contributions will play a vital role in maintaining the smooth and scalable operation of our financial processes.We value engineers who take initiative, enjoy tackling complex challenges, and excel at clarifying ambiguous requirements. You will thrive in our environment if you are motivated by creating systems that deliver tangible business impact, can articulate technical concepts to non-technical partners, and take pride in producing high-quality, well-designed code.At abound, you will immerse yourself in a culture that champions autonomy, curiosity, and continuous improvement. You will engage with a modern Python-based tech stack, gain in-depth insights into how financial operations function in a rapidly growing lending business, and have the opportunity to enact significant technical changes in collaboration with experienced stakeholders.

Join G MASS as a Senior Software Engineer and play a pivotal role in supporting a prominent Investment Manager. This initial 6-month engagement places you within a core engineering team that operates in a dynamic, quantitative investment setting. You will be integral in enhancing the technology and data frameworks that power systematic trading strategies and cutting-edge research. Your contributions will enable investment teams to efficiently access, process, and leverage extensive market and research data in a fast-paced, analytics-driven environment.Key Responsibilities:Architect, develop, and refine large-scale data and infrastructure platforms that underpin trading and research activities.Establish and sustain systems designed to process vast amounts of data from a variety of global sources.Collaborate closely with researchers, traders, and fellow engineers to ensure seamless support for investment workflows.Enhance the scalability, performance, and reliability of distributed systems.Utilize Java and Python primarily in the development and maintenance of services.Engage with modern data and messaging technologies, including Kafka, ArcticDB, and MongoDB.

Join Nevis: Pioneering AI Wealth ManagementAt Nevis, we're on a mission to revolutionize wealth management through cutting-edge AI technology. Our innovative platform is designed to empower financial advisors, enabling them to enhance client relationships while our AI automates time-consuming workflows. As we build the future of wealth management, we have secured $40 million in funding from top-tier investors including Sequoia Capital, ICONIQ, and Ribbit, and are led by a talented team of ex-Revolut executives.Your Impact as a Software Engineer (Python)We are seeking a talented Software Engineer (Python) who is passionate about developing robust AI-driven platforms. In this key role, you will design and implement Python-based systems and services that drive intelligent workflows for leading financial firms. You will work on applied AI, data pipelines, model execution frameworks, and backend components that support our innovative AI products.If you thrive in a fast-paced environment, love creating production-grade AI solutions, and are eager to see your ideas come to life quickly, Nevis is the place for you. You'll join a world-class engineering team dedicated to building scalable AI systems.Your ResponsibilitiesDesign and enhance Nevis’ Python-based AI platform, enabling core workflows and agentic automation.Develop model orchestration, data processing pipelines, and execution runtimes for our applied AI features.Create scalable APIs and services that facilitate rapid development and deployment of AI systems.Architect systems for model inference, prompt execution, and multi-step agent reasoning.Maintain high engineering standards through clean code practices and CI/CD workflows.Collaborate with AI engineers, product managers, and designers to deliver impactful features used by thousands.Take ownership of greenfield AI platform components, from architecture to production.Engage in design and code reviews that shape Nevis’ technical future.

Overview Join Tipalti as a Senior Software Engineer and play a crucial role in developing and delivering impactful product features that enhance customer satisfaction and address significant business challenges. Collaborate closely with Product Managers, Designers, and cross-functional engineering teams to transform product visions into scalable, secure, and maintainable software solutions. This role integrates hands-on engineering with a product-focused mindset, allowing you to define requirements, engage in technical discussions, and influence user experience while owning the entire software development lifecycle. Responsibilities Engineering & Delivery Create robust, efficient, and well-tested code across the software stack. Implement new features and enhancements in alignment with product priorities. Engage in design and architecture discussions to refine technical direction. Review code with peers, uphold clean code practices, and ensure quality standards are met. Product Collaboration Partner closely with Product Managers to clarify requirements and propose solutions. Proactively raise questions, identify edge cases, and assist in refining specifications. Contribute technical insights into prioritization and product decision-making. Cross-Functional Communication Communicate effectively with designers, engineers, and stakeholders. Share knowledge and mentor team members as appropriate. Collaborate with external partners and vendors on integration work when necessary. Requirements You are: Skilled in full-stack development and enthusiastic about learning new technologies. Committed to writing clean, maintainable, secure, and thoroughly tested code. Collaborative and communicative, thriving in team environments. Curious about customer needs, adept at translating them into technical solutions. Dedicated to continuous learning and sharing insights with your team. Preferred Technical Skills Proficient in JavaScript / TypeScript, Node.js, React (or similar technologies). Experience with REST APIs or microservices. Familiarity with MongoDB. Knowledge of cloud services, particularly AWS. Why Join Tipalti? Become part of an innovative and dynamic team at Tipalti, where your contributions will directly impact the growth and success of our products and services.

Join Carta as a Senior Software Engineer and play a vital role in developing innovative software solutions that empower businesses and transform the way equity is managed. Collaborate with a talented team of engineers to create scalable applications that enhance user experience and drive efficiency.

Genomics England is looking for a Platform Engineer based in London. This full-time position centers on building and maintaining the platforms that enable genomic analysis and data processing. The work directly contributes to making genomic data more accessible and valuable for healthcare. Key responsibilities Develop and maintain platforms that handle genomic data analysis. Collaborate with cross-functional teams to design effective solutions. Ensure data processing systems are reliable and efficient to support ongoing research. Role focus This role supports research and healthcare initiatives by providing stable and scalable technology for genomic data. Platform Engineers at Genomics England play a part in advancing how genomic information is used in medical settings.

We are looking for a Senior Staff Python Software Engineer to join our dynamic team at abound. In this role, you'll leverage your expertise in Python to design, develop, and maintain high-quality software solutions that meet our clients' needs. You'll work closely with cross-functional teams to deliver innovative products that drive our mission forward.

Join Our Innovative Team At Octopus Legacy, we're proud to be one of the UK's most rapidly expanding tech firms, dedicated to reshaping an age-old industry. Our mission is to support individuals and organizations in navigating and finding solace after the loss of loved ones. As we strive to become a household name, we recognize that our journey towards transformation requires the right talent. We're seeking proactive, solution-oriented individuals who are passionate about making a difference. Your Role We are in search of a skilled Software Engineer proficient in PHP, with a working knowledge of Python, who is eager to make a significant impact. You will be responsible for enhancing and maintaining our existing PHP/Laravel applications, which power key products including our website and internal tools, while also contributing to new Python-based initiatives as our technological landscape evolves. Your role will encompass full-stack development, delivering tangible enhancements that our users will appreciate, ensuring our platforms remain secure and efficient. You will manage a backlog of substantial changes that will elevate our products and enrich user experiences, while also expanding your expertise in Python. This position offers a dynamic work environment with a variety of challenges each week, allowing you to directly influence our customers' experiences. Key Responsibilities Enhance and maintain existing PHP/Laravel applications, focusing on bug fixes, performance enhancements, and security improvements. Develop and contribute to Python projects, including new services and internal integrations, as our technology evolves. Assist with platform security and compliance efforts, including vulnerability remediation and system hardening. Diagnose and resolve production issues, ensuring swift and effective solutions. Collaborate with the broader engineering team through code reviews and agile ceremonies, contributing to our engineering standards. Lead small-to-medium projects from inception to completion, implementing impactful changes across our tools and products. Who You Are Extensive experience with PHP, preferably within the Laravel framework. Proficient in Python, with experience in scripting, APIs, or frameworks such as Django or FastAPI. Strong understanding of relational databases like PostgreSQL and the ability to write efficient queries. Excellent problem-solving skills and a proactive approach to work. Ability to work collaboratively in a fast-paced, team-oriented environment.

Join Edra: Pioneering Solutions in Enterprise AIAt Edra, we're tackling one of the most challenging issues in enterprise AI: while AI models are inherently generic, company processes are uniquely specific. Our mission is to develop AI agents that comprehend how these processes operate and effectively manage their tasks.As a Series A startup, we are proudly supported by Sequoia and other prestigious venture capital firms. With our teams expanding in New York and London, we are a highly technical group comprising engineers, AI researchers, and strategists who all uphold a rigorous standard for talent. We believe that exceptional individuals are the cornerstone of our future success.Your RoleWe seek dedicated Backend Engineers who are passionate about the art of software development. Your focus will be on implementing strong typing, thoughtful API design, and robust data modeling. You will not be developing AI models; instead, you will construct the surrounding ecosystem: the platform, workflows, interfaces, integrations, and observability that render our AI applicable in real-world scenarios. As one of the early engineers at Edra, you will have the opportunity to influence not only the product but also the engineering culture, tooling decisions, and technical frameworks upon which our company is built.Our approach is intentional and thorough. There is no distinction between 'building it' and 'shipping it'—you will oversee the journey from conceptualization to deployment, taking full ownership of your outcomes. We prioritize thoughtful development over speed, striving for a balance between velocity and quality.Key ResponsibilitiesDesign and implement platform systems utilizing Python (FastAPI), including API contracts, database schemas, and infrastructureDevelop and sustain connectors, integrations, and data pipelines that link our platform to external systemsCreate internal libraries, tools, and interfaces that enhance the productivity of the engineering teamTake full ownership of your work by gathering context, managing dependencies, and driving tasks to completion independentlyEngage in multiple roles across the stack—design a schema in the morning, develop the API layer in the afternoon, and troubleshoot a deployment issue by day’s endParticipate in weekly product meetings, understand user interactions with your creations, and help shape future developmentsCollaborate daily with a small, elite team of engineers and AI specialistsHave a direct impact on the technical direction: select tools, establish patterns, and define conventions for the team

Talan is looking for a Python Developer to join its London office. This position centers on building and maintaining applications for a variety of client projects. The work includes both new software development and ongoing support, with a strong emphasis on delivering solutions that meet business needs. Key responsibilities Design, develop, and maintain Python-based applications Collaborate with colleagues across different teams to achieve project objectives Take part in planning and implementing technical solutions Support existing systems and address issues as they come up Role overview This role involves hands-on development as well as troubleshooting and supporting live systems. Working in a collaborative environment, the Python Developer will contribute to projects that serve a diverse group of clients.

Location: London, UK (hybrid) Role Type: Full-time Join our innovative team at Materiom as a Senior Software Engineer. In this pivotal role, you will engage in the rapid prototyping, development, and productization of data-driven and AI-centric web applications. Your contributions will play a vital role in overcoming R&D challenges for pioneers in bio-based materials. You will be tasked with designing and building robust full-stack systems, making significant architectural contributions, and translating complex user needs into actionable technical strategies. You will also champion engineering best practices within our mission-driven startup culture. Your technical prowess across the stack, particularly on the front end, combined with a product-focused approach, will ensure the delivery of high-impact results. As you design user-centric applications, you will transform prototypes into actionable solutions that propel Materiom’s mission forward. Collaborating closely with Materiom's senior leadership team, including the Co-CEOs and CTO, you will be instrumental in shaping our product and platform. #python #fastapi #react #typescript #GCP #PostgresSQL

Genomics England seeks a Principal Data Engineer based in London. This senior role centers on building and maintaining the data systems that power the company’s work in healthcare and genomics. The position involves designing and implementing solutions that turn genomic data into insights for better patient outcomes. Key responsibilities Design and develop infrastructure to manage large-scale genomic data projects. Collaborate with teams across Genomics England to identify data needs and deliver tailored solutions. Maintain data integrity and ensure accessibility throughout all systems. Influence and shape the company’s data engineering practices and standards. Requirements Significant experience in data engineering, preferably within complex or scientific settings. Proven ability to design, build, and optimize data systems. Comfort working alongside colleagues from a range of disciplines. Strong commitment to data quality and security.

Role overview LMAX seeks a C++ and Python Developer to join its Middle-Office Team in London. This group works alongside infrastructure, research, and treasury teams to advance trade reconciliation, back-testing frameworks, and trading monitoring systems. The main focus lies in data engineering and building trading systems from the ground up. Prior experience in finance or trading is not required for this position. Team approach The team operates at the intersection of C++ and Python. C++ powers the infrastructure, while Python supports research tasks like analysis and automation. Bridging these languages is central to the role, supporting integration and collaboration across disciplines. Performance and optimization Managing financial data introduces technical challenges, particularly around throughput. The team values software performance but never at the expense of maintainability. Developers work closely with the codebase to understand, optimize, and refine systems. Testing practices Comprehensive testing is a core part of the workflow. The team maintains test suites that include unit tests and full end-to-end simulations. Continuous integration runs these tests every 15 minutes, ensuring rapid feedback and no overnight waits for results. What you will do Write clear, well-structured, and thoroughly tested code in C++ and Python Develop software solutions that handle high throughput Pair program to share knowledge and prevent silos Design and implement features to enhance safety, performance, and usability Create interface code connecting C++ and Python using pybind Requirements Strong C++ skills, especially with modern C++ on Linux or UNIX Python development experience, including Numpy, Pandas, and SQL Experience with automated testing for both C++ and Python Ability to interpret business requirements and build effective systems Skilled at designing simple, well-documented, and maintainable solutions Comfortable working independently with minimal supervision No finance or trading background needed Bonus skills Experience with test-driven development and testing across multiple system levels Location This position is based in London, England, United Kingdom.

About the Role Weekday-1 is hiring a Senior Software Engineer in London to help build and scale intelligent systems with Python and Large Language Models (LLMs). This role focuses on designing, developing, and deploying AI-driven solutions for real-world problems. What You Will Do Design and implement systems that use LLMs in production settings Work across the full development lifecycle, from architecture through deployment Collaborate closely with product, data, and research teams to deliver reliable, high-performing solutions Ensure that AI systems meet performance and reliability standards What We’re Looking For Extensive experience with Python Strong background in integrating and scaling Large Language Models Ability to work collaboratively as a senior member of an engineering team Location This position is based in London, England, United Kingdom.