Linux Engineer at Jane Street | London

About the RoleJoin our dynamic team as a Programming Language Engineer, where your expertise in software engineering and programming languages will be pivotal to our growth. At Jane Street, we are dedicated to enhancing OCaml, which serves as a crucial component of our extensive technology stack. By collaborating with the broader OCaml community, we strive to refine various aspects of the language, making it easier for developers to articulate their ideas, optimize code performance, and enhance the usability of the OCaml compiler.Our ongoing projects include extending the type system to incorporate innovative language features, completely re-engineering the optimizer, and implementing feedback-directed optimization strategies. We also focus on enriching the toolchain by developing tools for profiling, debugging, and generating documentation. A significant portion of our contributions is open-source, and we actively upstream enhancements to the mainstream OCaml compiler.

About the Role Jane Street is seeking talented Software Engineers who are eager to contribute to the design and development of the systems and tools that drive our operations. Our Software Engineers are integrated throughout the company, tackling complex challenges that span from trading desks to accounting, as well as creating essential infrastructure, including network monitoring solutions and risk models. We are strong advocates of functional programming, primarily utilizing OCaml, a statically-typed functional programming language. Recently, Python has emerged as a crucial component in our research and trading initiatives, serving as the primary language for data analysis, visualization, and machine learning. In addition to our internal practices, we value the significance of open-source software. We actively incorporate it into our daily operations and have released over a million lines of our code as open source. We are continually looking for ways to enhance open-source projects and provide ongoing support for tools like Mercurial, the OCaml compiler, and the OPAM package manager. We welcome passionate engineers with experience in any programming language; most of our team members started with minimal practical knowledge of OCaml. To learn more about our interview process and meet some of our newest hires, feel free to explore.

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 the RoleJane Street is seeking a skilled Data Engineer to enhance our understanding, management, and dissemination of data that informs our trading strategies. At Jane Street, the ability to comprehend and manipulate data accurately is fundamental to our operations.In this role, you will utilize a combination of proprietary and open-source tools to analyze diverse datasets, identifying anomalies, ensuring consistency in formats and symbologies, automating ETL processes, and ultimately simplifying the process for our traders to derive insightful conclusions.We are looking for someone who is passionate about diving deep into data and articulating findings to various stakeholders, collaborating closely with traders and software engineers.While familiarity with financial data is beneficial, we do not require a financial background. We are eager to hire talented engineers and provide the necessary training.

About the Position Jane Street is seeking a talented FPGA Engineer with a strong foundation in both software and hardware design to join our innovative team. In this role, you will play a pivotal part in developing our cutting-edge FPGA-based applications. We are passionate about leveraging tools to enhance programming efficiency, enjoyment, and reliability. We apply these principles within our FPGA Engineering endeavors, and we invite individuals who are keen on utilizing programming language technology to elevate the design, testing, and validation of hardware designs. Our development environment heavily incorporates Hardcaml, an OCaml library designed for succinct hardware description in RTL. Familiarity with Hardcaml is not a prerequisite. As an FPGA Engineer, you will engage in designing and implementing new FPGA applications from the ground up, as well as improving our internal high-level design and testing tools. Your daily responsibilities will primarily involve working with OCaml and Hardcaml for RTL design and testing/integration, while also occasionally utilizing Verilog and C. While prior experience with OCaml is not necessary, a solid understanding of typed programming languages will be beneficial. If you're interested in learning more about our interview process, feel free to explore our interview guide, meet some of our newest hires, or check out our OCaml All The Way Down talk as well as the Programmable Hardware podcast.

About the Role We are seeking talented Production Engineers to join our London office. At Jane Street, Production Engineers are skilled software developers who engage in both software development and provide essential support for critical software systems integral to our trading operations. Our Production Engineers are often embedded within various software teams, while others work in dedicated teams. In both scenarios, we collaborate closely with application developers, all aiming to create and maintain outstanding software systems. We strongly advocate for functional programming and primarily utilize OCaml as our development language. As a Production Engineer, you will play a vital role by interacting with diverse departments and functions across Jane Street. You will tackle real-time challenges and make a significant impact across the firm. You will take ownership of the design and architecture of systems that monitor and support our trading activities. Additionally, you will design and develop the tools we utilize, allowing you to influence their evolution positively. If you wish to explore more, visit Production Engineering at Jane Street.

About the RoleAt Jane Street, we are diligently working on OxCaml, an enhanced branch of OCaml designed to optimize performance engineering. However, creating and implementing the language is just part of the journey; we need our developers to master its intricacies and utilize OxCaml like true professionals. That’s where you come in.We are on the lookout for a talented and experienced educator to assist us in developing educational materials and delivering comprehensive courses aimed at teaching our engineers to effectively harness the power of OxCaml. You will engage widely within our internal educational framework, from enhancing our OCaml Bootcamp for new hires to crafting specialized tutorials that empower seasoned developers to leverage OxCaml’s most advanced capabilities.This is a remarkable opportunity to collaborate closely with the designers and implementers of the language in building its educational framework. You will be an integral part of the Jane Street team, shaping the future of OxCaml.

About the PositionJane Street is seeking a talented and experienced ASIC Engineer to join our Ultra Low Latency team, where you will play a pivotal role in designing, testing, and deploying cutting-edge hardware solutions. In this collaborative environment, you will work closely with various teams across the firm, including trading, networking, and research infrastructure. We value versatility and are looking for someone comfortable with both FPGA and ASIC technologies.We believe in the transformative power of tools to enhance productivity, reliability, and enjoyment in hardware engineering. That's why we developed Hardcaml, a hardware development toolchain integrated with OCaml. While prior knowledge of OCaml is not a prerequisite (we will provide training), we seek hardware engineers who are enthusiastic about leveraging superior tools and are open to exploring innovative approaches.

About the RoleJane Street is seeking a passionate and proactive Technical Product Manager to provide organizational and coordination support for our dynamic engineering initiatives. As technology is at the heart of our business operations, this position presents a unique opportunity to collaborate closely with our engineering team as we enhance and optimize Jane Street's trading technology.In this role, you will leverage your technical expertise daily, guiding projects from inception through completion. This includes setting objectives, developing timelines, tracking progress, managing developer resources, identifying potential risks, and liaising with cross-functional teams. You will also communicate project schedules, priorities, and updates to the wider organization.Exceptional communication skills and the capacity to juggle multiple priorities are essential for successful collaboration with various teams at Jane Street—including developers, business units, operations, and support—as well as external financial entities. Your goal will be to ensure that projects are delivered punctually and meet or surpass established goals and expectations.We foster a flexible problem-solving environment that inspires innovative thinking when developing processes and tools for each project. The successful candidate will be a strategic thinker who aligns with the team's and project's objectives when tackling challenges.This position is part of Jane Street's technology group, which designs, implements, and supports the vital infrastructure supporting our trading activities. The scope of our systems is extensive, providing insight into a broad array of global markets as you work to enhance them. To thrive in this role, you should enjoy working autonomously within small teams, adapting quickly to new information, and making impactful decisions for the firm.At Jane Street, the “P” in TPM encompasses various roles. Depending on the team, individual, and specific circumstances, you may find yourself functioning anywhere along the spectrum from Product Manager to Program Manager. Thus, you will excel at Jane Street if you are comfortable with ambiguity and eager to engage with the task at hand, applying your relevant skills, whether through extensive program management and coordination, product vision, or business context. This is also why you will find a corresponding job posting for “Technical Program Manager” elsewhere on our site that mirrors this one—feel free to apply to whichever role aligns better with your experience and interests, and we will ensure your application is directed to the appropriate pipeline.

About the Position Jane Street is seeking a dedicated Cybersecurity Analyst to join our London office, playing a crucial role in safeguarding our employees, data, and infrastructure from online threats. As a Cybersecurity Analyst, you will be responsible for developing and utilizing monitoring tools to protect our firm, as well as managing incident response and remediation when threats are detected. Our Cybersecurity team consists of talented programmers and security professionals committed to maintaining the safety of our organization. We pride ourselves on staying abreast of the latest developments in the cybersecurity landscape, distinguishing between notable hacks by security researchers and the critical issues that impact our daily operations. In this position, you'll be expected to thoughtfully assess the context of our decisions, weighing the trade-offs in our approach to resolving cybersecurity challenges. You will employ a systematic methodology to conduct unstructured investigations, identifying and rectifying the root causes of security incidents. Additionally, you will serve as an ambassador of cybersecurity best practices within the firm. Our team members are encouraged to understand and implement good personal cybersecurity hygiene and communicate effectively about it with others. A significant aspect of success in this role involves bringing your colleagues along on the cybersecurity journey, fostering an environment of learning and collaboration.

About the Position Jane Street is seeking an experienced UK Tax Lawyer to join our London office, where you will play a vital role in tax structuring and advisory. You will be instrumental in managing tax implications and structural considerations for internal restructurings, including investment frameworks for senior group members and complex transactions such as acquisitions and dispositions. Your expertise will also extend to structuring and advisory matters related to the firm's trading activities. This position offers you the chance to collaborate closely with our local and global Tax team as well as with various professionals across the organization, making it an exciting opportunity to engage with a dynamic and entrepreneurial work environment. The ideal candidate will be commercially driven, exceptionally comfortable with numerical data, highly collaborative, and thrive under tight deadlines.

About the Position We are seeking a proactive Cybersecurity Engineer to enhance the security framework of our applications, data, infrastructure, and processes within our dedicated Cybersecurity team. This role merges hands-on technical skills to identify and mitigate vulnerabilities with the ability to collaborate effectively across various teams. You will guide your peers in assessing the security implications of design choices and ensure that security is integrated into applications from inception. Utilizing your offensive security expertise, you will pinpoint potential threats and delve into intricate technical aspects to craft tailored security solutions while navigating complex challenges with innovative approaches. Practical experience in threat modeling is essential, along with the capacity to translate security principles into tangible architectural advancements. Additionally, you will engage with system owners who possess in-depth knowledge of their applications but may overlook potential vulnerabilities. Your role will involve collaborating with them to identify and resolve these issues, weighing the balance between security measures and business needs. As part of the Cybersecurity team, you'll collaborate with a talented group of programmers and security professionals dedicated to safeguarding the firm. Our work encompasses a broad spectrum of topics, including software engineering, DevOps, risk analysis, security governance, and cyber awareness.

About the Role At Jane Street, our quantitative traders excel in identifying market signals, analyzing and executing strategies, and constructing sophisticated quantitative models. You will conduct statistical analyses, build algorithmic trading systems, manage risk, and contribute to the development of new business initiatives. Our trading desks are integral to our collaborative and cooperative office culture. You will work closely with seasoned traders committed to mentoring and supporting our new team members. Through interactive, hands-on training, you’ll take on significant trading responsibilities within weeks to months of joining our team, complemented by a comprehensive year-long educational curriculum across the firm. At Jane Street, we intentionally blur the lines between research, technology, and trading. As our strategies become increasingly sophisticated, collaboration is vital to push the boundaries of what we can achieve. We leverage petabytes of data, operate a computing cluster with hundreds of thousands of cores, and maintain a growing GPU cluster featuring thousands of high-end GPUs. We embrace a diversity of statistical and machine learning techniques, from linear models to deep learning, tailored to fit the specific challenges we face.

Join Jane Street as a Front End Software Engineer, where your passion for front-end development and user-interface design will drive the creation of innovative browser-based tools for our trading infrastructure. As we cater to expert users, our goal is to uphold an exceptional user experience while crafting tools that are both flexible and powerful enough to meet the demands of our highly engaged clientele. In this role, you will not only contribute to individual tools but also identify opportunities to develop libraries and abstractions that encapsulate common interaction patterns, enhancing our development practices and overall approach to UI development.

About the Position Join Jane Street as a Senior Network Engineer, where you will play a pivotal role in enhancing our network infrastructure to accommodate growing business demands. Your expertise will help drive automation and explore innovative AI solutions to optimize our operations. At Jane Street, we operate a multi-vendor, highly available network infrastructure that supports diverse traffic profiles, from high-speed trading to standard internet connectivity. A typical day on the Network Engineering team includes: Collaborating on new data centre and colocation initiatives, optimizing WAN routing, and engaging in cross-team design projects. Interfacing with stakeholders to identify business needs and develop cutting-edge network features and capabilities. Leading reactive support tasks while also initiating proactive infrastructure enhancements, ensuring detailed documentation to minimize outages and improve troubleshooting efficiency. Exploring AI and machine learning enhancements to streamline operations and continuously elevate service quality. Utilizing your networking expertise to scale our infrastructure while maintaining exceptional standards for performance and reliability. Documenting solutions and processes meticulously to enhance team efficiency. If you are passionate about innovation in a complex network ecosystem, excel at building scalable systems and documentation structures, and are curious about the applications of AI in network operations, this role offers a significant opportunity to impact Jane Street. We are excited to learn from your expertise and unique insights.

About the PositionJoin our dynamic team as a Network Analyst, where you will play a crucial role in developing automation and DevOps-driven solutions while harnessing the potential of AI. You will be instrumental in supporting our global network infrastructure, which services various traffic profiles, from high-speed trading to extensive internet connectivity.In this position, you will collaborate with senior engineers and developers to refine existing workflows, optimize processes, and ensure our network's stability, security, and adaptability. We are looking for candidates who are passionate about solving complex challenges and eager to deepen their skills in operations and innovative infrastructure engineering.Your typical day will involve:Providing hands-on support to troubleshoot and resolve network issues across LAN, WAN, and colocation environments.Collaborating with project managers on site expansions, integrating new market data feeds, and establishing connections to third-party services.Enhancing our monitoring and alert systems with a focus on automation, AI integration, and DevOps methodologies.Utilizing scripting or development tools to minimize manual tasks, increase network visibility, and explore cutting-edge AI-driven solutions.This role offers an incredible opportunity to learn from experienced network engineers using state-of-the-art hardware, protocols, and DevOps tools. Your contributions to automation, AI integration, and innovative tooling will significantly impact our operational excellence and shape the future of our network.

About the RoleThe Operations team plays a pivotal role in the trading activities at Jane Street. We oversee the processes that connect us with external partners as well as those that facilitate internal collaboration. Our objective is to ensure the seamless movement of assets, information, and ideas with precision, control, and efficiency. The challenges we face are substantial, and we strongly believe in recruiting exceptional, intelligent individuals to address them.Our Operations team is collaborative and integrated, thriving in a dynamic environment where the best ideas prevail. As a key member of our team, you will focus on trade settlements, trade record and position management, or cost and cash management. You will collaborate closely with external service providers and trading partners, as well as colleagues locally and globally. Together, you will tackle issues arising from our complex trading flows and ensure our processes run smoothly.If you have never considered a career in finance, you’ll fit right in as many of our team members began their journeys in finance at Jane Street. We prioritize how you think and learn. You will engage with a diverse range of financial products including equities, bonds, ETFs, futures, and swaps, regardless of your prior knowledge or experience. We seek bright, eager learners from Day One.

About the Position As a Quantitative Trader at Jane Street, you will be part of a dynamic team that leverages proprietary models to execute over a million trades on busy days. Our traders collaborate to identify and capitalize on pricing inefficiencies, develop innovative models, manage risk, explore new products, and expand into emerging business areas. Experienced traders mentor and guide their less-experienced colleagues, allowing new traders to grow into their roles with increasing responsibility. At Jane Street, technology is integral to our trading strategy. We pride ourselves on being as much a technology firm as a trading company. Our primary programming language is OCaml, a statically-typed functional programming language, and we boast the largest team of OCaml engineers in any industrial context.

About the RoleJane Street is seeking a skilled Infrastructure Security Engineer with a robust background in Windows engineering and hands-on experience with contemporary platform security measures to enhance the security of our IT platforms globally. In this pivotal role, you will exercise sound judgement and a keen sense of priorities to manage complex remediation tasks effectively. Your insights will guide our mitigation strategies and provide essential technical guidance for the team.Your responsibilities will include proactively designing, testing, implementing, and documenting strategic security measures. You will lead the coordination and delivery of security solutions across our IT infrastructure while discovering opportunities to automate intelligent workflows. Your expertise will be vital in securing both internal IT and remote working environments through a blend of technical execution, consultancy, and influence over the broader IT team. This position encompasses a variety of tasks, including building scalable security controls, investigating emerging threats, developing innovative security tools, and spearheading vulnerability management initiatives.As part of our IT Engineering department, you will collaborate with a dedicated team of engineers who oversee our operations across a diverse physical and virtual computing landscape spanning three continents. Your analytical skills and technical proficiency will be crucial in supporting our colleagues' daily operations and maintaining our systems at peak performance.