Linux Engineer

Maven Securities Holding Ltd is a distinguished proprietary trading firm that adeptly allocates internal capital across a range of strategies, including discretionary, systematic, and market-making approaches. Our team's extensive expertise encompasses traders, engineers, and technologists, all committed to optimizing our efficiency as a leading liquidity provider for globally traded derivatives. At Maven, we foster a relaxed yet rewarding culture that highly values exceptional performance. With offices located in London, Amsterdam, Hong Kong, New York, and Chicago, our Infrastructure team comprises open-minded technologists dedicated to the continuous enhancement of the end-to-end resiliency, scalability, visibility, and supportability of Maven's trading systems. The Team and the Role The Linux Engineering team is tasked with the deployment, maintenance, and stability of Maven's Linux server environment. This estate spans 10 data centers across Europe and the US, supporting all trading applications. Our infrastructure includes both bare-metal deployments and containers, facilitated by an expanding array of Kubernetes clusters, all operating on-premises. The team operates from Chicago and London, covering both European and US market hours. We proactively monitor our infrastructure for any faults and performance issues, translate technical challenges for our trading teams, design and test new hardware, kernels, and operating systems, manage centralized storage arrays that support our data pipelines, and stay up-to-date with the latest developments in the Linux open-source community. We leverage a variety of open-source tools to extract comprehensive data from our platform and dedicate time to thoroughly investigate issues to ensure we maintain a clear understanding of our environment.

ABOUT THE COMPANY: Maven is a leading proprietary trading firm, strategically allocating internal capital across a spectrum of discretionary, systematic, and market-making strategies. Our diverse team of traders, engineers, and technologists is united by a shared commitment to enhancing our capabilities as a premier liquidity provider in global derivatives markets. We utilize cutting-edge execution and pricing technologies to redefine the operational landscape of financial markets. Overview: At the intersection of technology and trading, the Maven FPGA team is at the forefront of hardware innovation, developing proprietary designs that maintain our competitive edge in an evolving landscape. With offices in London, New York, Hong Kong, and Chicago, we engineer solutions to support global trading operations across various exchanges, asset classes, and trading strategies. Our small, agile teams are dedicated to growth, investing in people, tools, and platforms to solidify our leadership in the industry. The Role: As a key member of our team, you will collaborate with traders and technologists to identify and leverage opportunities that enhance our competitive advantage through FPGA systems. By optimizing latencies, maximizing throughput, and improving system robustness, you will play a pivotal role in boosting the efficiency of existing strategies and unlocking new trading opportunities. We have several greenfield projects on the horizon, and proactive, self-motivated candidates will have the opportunity to ascend into leadership roles as the firm continues to evolve. While financial experience is advantageous, your engineering skills, problem-solving capabilities, and readiness to tackle new challenges are of paramount importance to us.

Maven Securities Holding Ltd is a leading proprietary trading firm, leveraging internal capital across a variety of strategies including discretionary, systematic, and market-making. Our diverse team of traders, engineers, and technologists is dedicated to optimizing our role as a top-tier liquidity provider for globally traded derivatives. We utilize innovative execution and pricing technologies to enhance the functionality of financial markets. As Maven grows, we maintain the vibrant energy and innovative culture of a startup, while minimizing associated risks. Key Responsibilities:Build Advanced Analytics Framework: Create scalable Python libraries and tools to standardize performance metrics across teams, establishing automated workflows that transform raw trading data into valuable insights for Portfolio Managers and the Investment Committee.Conduct In-Depth Quantitative Research: Execute comprehensive statistical analyses on trade and portfolio-level data to dissect PnL drivers. Identify alpha decay, inefficiencies, and execution challenges to provide actionable insights that enhance performance.Optimize Existing Strategies: Analyze trade and strategy performance to pinpoint areas for optimization and efficiency improvements. Deliver data-backed recommendations and ensure follow-through.Identify Trading Risks & Opportunities: Monitor portfolio exposures, performance trends, and market signals to detect emerging risks and uncover underutilized or mispriced opportunities across various strategies.Assist in Strategy Development: Support the onboarding process for Portfolio Managers and contribute to business development initiatives involving new product groups and strategies.

Maven’s Systematic Alpha team is seeking exceptional portfolio managers to contribute to our global expansion. Our group utilizes meticulously researched strategies in trading across futures, options, and equities. We adopt a scientific and process-oriented trading approach, fostering a flexible research environment that efficiently facilitates the development, testing, and implementation of innovative ideas. The Role: This is a remarkable opportunity to research, develop, and execute systematic strategies across listed instruments such as futures and FX. You will take full ownership of the trade/strategy life-cycle, actively monitoring and managing portfolio risk to optimize the risk/reward profile. We promote a collaborative environment with our Quant PMs, encouraging teamwork and shared success. What We’re Looking For: The ideal candidate will possess a comprehensive understanding of the systematic inefficiencies they aim to exploit. They will have played a pivotal role in the research and execution of the strategy and will be adept at developing new strategies from concept to implementation. 3+ years of experience as a Portfolio Manager or 4-5 years as an Assistant Portfolio Manager; Realized Sharpe ratio greater than 2.5; Proven track record of successful strategy execution; In-depth knowledge of the strategy; Robust coding expertise; Strong research capabilities; Master's degree or PhD in a scientific discipline; Experience working with large time series data; Excellent programming skills in Python or Julia. Why You Should Apply: Join a highly rewarding, collaborative, and successful trading firm; Enjoy a flexible research environment for developing, testing, and deploying new ideas; Work in a tech-driven environment where technology is critical to our success; Thrive in a supportive atmosphere that empowers you to achieve your ambitions; Experience a friendly, informal, and rewarding culture.

Thank you for considering a future with Maven Securities Holding Ltd! We invite you to register your interest in our exciting roles and be among the first to know when applications open. This is a great opportunity to explore a career with us! In the meantime, we encourage you to visit our website and follow us on social media to stay informed about our latest news and events. We are eager to review your application soon!

About the PositionAs a Linux Engineer at Jane Street, you will be integral to the vital infrastructure that supports our technology landscape. Our team comprises dedicated Systems Engineers, Administrators, and Programmers focused on maintaining and enhancing the platform that drives our production trading systems. Our unique blend of in-house and open-source software empowers you to explore and innovate at every level. Each day presents opportunities to debug kernel performance, develop management tools, or tackle production issues in real time. We thrive on solving complex systems challenges.Our ongoing projects emphasize deployment automation, scalable configuration management, and meticulous monitoring. While we automate as much as possible, it's not out of laziness. We believe that automation minimizes errors and reduces workloads, not to mention that it adds an element of enjoyment to our tasks.Being part of our group opens avenues to collaborate with various departments across the company. We engage directly with colleagues in Trading, Technology, and Operations to design and maintain systems that have a company-wide impact. Utilizing feedback from other teams and our tailored monitoring tools, we aim to swiftly resolve production issues, conduct thorough root-cause analyses, and implement long-term solutions in a clean and robust manner.

Maven Securities Holding Ltd is a cutting-edge proprietary trading firm established in 2011, with a global presence that includes offices in London, Amsterdam, Chicago, New York, Hong Kong, and Monaco. We pride ourselves on having a team of exceptionally skilled traders, developers, engineers, and operational staff who execute a wide variety of market-making and position-taking strategies across global derivatives, equities, and debt instruments. Our culture is relaxed and informal, yet we are fiercely dedicated to high performance and rewarding excellence. The Risk team at Maven is at the forefront of innovative risk management practices, overseeing the extensive trading operations across our organization. We are a cohesive global unit that integrates risk management, technology, and development to create and implement advanced systems while ensuring meticulous monitoring of trading exposures across the firm. This Risk Analyst position offers a unique opportunity for an outstanding individual with specialized expertise in options risk management. Based in our London office, you will collaborate with experienced risk team members from our Hong Kong and Chicago locations. The successful candidate will gain insights into our diverse business activities and strategies while serving as the first line of risk management oversight for critical trading functions. The proprietary risk systems we utilize set the parameters for effective risk management, and as Maven grows and diversifies our strategies, our risk monitoring systems and processes evolve in complexity and sophistication. The Risk Analyst will be tasked with updating and managing daily risk processes and conducting thorough risk monitoring—an essential responsibility given the volume and variety of trades processed. Additionally, you will be involved in interpreting and developing risk metrics, contributing to the enhancement of our risk management practices, and collaborating with the wider team to refine our systems, controls, and procedures. Communication with traders across Europe and our global trading hubs will also be a key aspect of this role. If you excel in a dynamic environment, possess a natural curiosity for the financial markets, and have a foundational understanding of trading and risk concepts, we are committed to helping you evolve into a leading Risk Analyst in the industry.

Causaly develops an AI-powered platform designed to help researchers and decision-makers in biomedicine quickly find and interpret evidence from scientific publications, clinical trials, regulatory documents, and complex data sources. The company’s mission centers on building a high-precision Knowledge Graph and applying generative AI to advance biomedical knowledge. Leading biopharmaceutical organizations use Causaly’s technology to accelerate drug discovery, improve safety, and support informed decisions. With backing from investors such as ICONIQ, Index Ventures, Pentech, and Marathon, Causaly continues to expand its product offerings and market reach. Role overview The Senior Security Engineer position at Causaly is based in London and offers the chance to shape the company’s security strategy and processes. This role provides significant autonomy and involves working closely with the security team, as well as collaborating across engineering and product groups. The Security Engineer will take ownership of vulnerability management, advise teams on security matters, and support SecOps activities. Expect to define strategies, build and refine processes, and serve as a trusted advisor throughout the engineering organization. Key responsibilities Lead the vulnerability management program: set strategy, select tools, prioritize work, and track remediation for dependencies, containers, and cloud infrastructure. Develop and maintain a dependency security strategy, including policies for third-party library use and update schedules. Integrate and manage security tools within CI/CD pipelines, such as SAST, SCA, secrets detection, and container scanning. Act as a security consultant for product and engineering teams, supporting design reviews, architecture decisions, and secure coding practices. Define and maintain security standards and guidelines that are practical for development teams. Oversee and improve the Security Champions program to build security awareness and skills across engineering teams. Support SecOps with incident triage and response, providing security engineering expertise when needed.

Join Longshot Systems Ltd, where we create cutting-edge platforms for sports betting, analytics, and trading. We are seeking a Senior DevOps Engineer to enhance our platform team.You will manage a medium-sized deployment that connects with global sports betting platforms and supports multiple internal teams with diverse infrastructure needs. Your role will involve overseeing critical systems from backtesting to real-time trading and long-running backend services.Our infrastructure is hosted on AWS, and we are undergoing an evolution focused on automation and repeatability to drive our growth. Our core systems process thousands of trading signals per second, requiring minimal latency, presenting similar challenges to high-frequency trading environments but in the sports betting sector.As a Senior DevOps Engineer, you will collaborate closely with the CTO and development team to maintain our production and development trading infrastructure. You will take the lead on developing new infrastructure and troubleshooting performance and stability issues across applications, networks, and operating systems. You should be adept at analyzing metrics, packet dumps, and logs to identify and resolve issues, followed by implementing automation to prevent future occurrences.The ideal candidate is autonomous and innovative, thriving on generating new solutions and suggesting improvements to current methodologies. We offer you flexibility and the freedom to explore effective solutions.We embrace a hybrid work model, requiring in-office attendance on Thursdays at our London (Farringdon) office, with flexible arrangements for the remainder of the week. Our standard working hours are 10 AM to 6 PM UK time, Monday to Friday, with support for flexible schedules to achieve your goals.Regarding on-call responsibilities, while we do not maintain a 24/7 rota, we have a compensated on-call system based on best efforts, which will involve sharing responsibilities within the platform team.Interview Process:Introductory call (30 mins) – discuss your background and interests.First technical interview (30 mins) – live systems management and code review.Second technical interview (60 mins) – in-depth technical questions.Full assessment day (10:30 AM – 5 PM) – a practical systems engineering exercise reflecting actual team work. Meet the team, tour the office, and enjoy a complimentary lunch.

Join PPRO, where our mission is to streamline access to local payment methods and our vision is to empower global commerce by enabling sales to anyone, anywhere, using their preferred payment method. We collaborate with industry leaders such as Ant Group, PayPal, and Stripe, helping them tap into new markets, engage a broader customer base, and drive growth.Our strength is rooted in our diverse team, comprising over 50 nationalities across more than 10 international locations, all working towards a shared goal: delivering exceptional products and services to our partners and customers. While we strive to innovate in global commerce, we also embrace internal values such as #chooseaction, #beopen, #thinkcustomer, #gofurther, and #wintogether.Role Overview:We are looking for a highly skilled and driven Senior Security Operations Engineer to join our vibrant security team. This pivotal role is essential to safeguarding PPRO against an ever-changing threat landscape. You will be responsible for identifying, analyzing, and responding to security incidents, focusing primarily on enhancing our detection capabilities through the creation of SIEM rules. You should be proactive, hands-on, and self-motivated, with a solid background in operational security and a passion for addressing complex challenges with state-of-the-art technologies. This position offers a unique opportunity to engage in various aspects of security operations within a dynamic, cloud-native environment.

CUBE delivers regulatory intelligence solutions to financial services firms worldwide. Our SaaS platform uses AI to help clients manage complex and changing compliance demands. With a global presence and a team spanning 19 countries, CUBE focuses on collaboration, diversity, and continual product improvement. In 2024, CUBE achieved 50% growth through both organic expansion and acquisitions. The company values ambition, bold thinking, and personal ownership, encouraging employees to shape their careers and contribute to ongoing innovation. Our team includes over 700 professionals working together to transform regulatory compliance for financial institutions. Role overview The Senior Security Engineer will strengthen security engineering standards across CUBE's products and platforms. This hands-on role sits within the growing security function and reports to the Head of Information Security. The position is based in London. What you will do Design and implement security controls for CUBE's SaaS products and internal platforms Integrate security practices into development workflows Develop automation and system integrations to scale security across the organization Promote security awareness and collaborate with teams to maintain high standards Requirements Strong hands-on experience in security engineering Proven ability to develop automation and integrate security tools into engineering workflows Collaborative approach and ability to promote security best practices across teams Comfort working in a role that involves building and creating new solutions

Join Us in Empowering the UK's Small Businesses At Funding Circle, we believe that small businesses are the backbone of the economy, and our mission is to provide them with the support they need to thrive. Our innovative platform leverages advanced data analytics to facilitate rapid access to funding, ensuring that our clients can secure the resources they need in mere minutes.Combining the agility of a fintech startup with the reliability of a publicly traded company, we offer Circlers the independence to take initiative while making a significant impact on the industry.We take pride in our high-performance culture, where collaboration and support are at the forefront. We uplift one another, challenge the status quo, and succeed together because we understand that unity accelerates progress and innovation.Your Contribution Matters: Last year alone, our platform enabled businesses to generate £7.2 billion for the UK economy Join us in making a difference![Explore Our Impact Report] | [Check Our Trustpilot]Your Role Location: London (Hybrid) | Work Schedule: 2 days in-office | Salary: Competitive + BenefitsLead the definition, advocacy, and integration of secure software development lifecycle (SSDLC) practices and secure coding standards throughout engineering teams via collaboration, training, and the use of tools.Conduct threat modeling exercises for cloud-native applications, microservices, and various infrastructure components.Oversee internal and external penetration testing engagements for Funding Circle's applications, services, and cloud infrastructure.Work closely with Cloud Platform Engineers, DevX, and Product Engineering to embed security requirements into system designs and technology choices from the beginning.Serve as a subject matter expert in DevSecOps, application security, and cloud security (AWS), offering guidance and mentorship to fellow engineers.Drive the implementation of security automation across cloud infrastructure configuration, vulnerability management, and compliance monitoring.Design, implement, and promote the adoption of robust security architectures, controls, and best practices within our AWS cloud environment.

Founded in 1987, ICTS UK Ltd is a leader in integrated security and customer services, delivering exceptional solutions in the most challenging environments. Our innovative approach allows us to collaborate with a diverse range of clients, including major public attractions, leisure facilities, financial institutions, retail, public sector organizations, transport services, and government entities.We are actively seeking dedicated Security Officers to join our esteemed team on high-profile contracts in the vibrant West London area. If you are looking for a fulfilling career where you can make a difference, we invite you to apply.As a Security Officer, you will be part of a close-knit team, requiring a commitment to reliability and flexibility. These positions are permanent and offer an immediate start.Key Responsibilities:Access ControlConducting Security PatrolsResponding to IncidentsProviding Excellent Customer ServiceReport WritingCompleting Daily Operational PaperworkAdhering to all company/client procedures and policiesFollowing all managerial directivesMaintaining High Standards of ProfessionalismPromoting ICTS UK Ltd positively at all times

Join Canonical as a Linux Desktop Support Engineer and elevate your career in a dynamic environment. Based in our London office, you will provide exceptional technical support to both employees and customers, ensuring seamless operation of our systems. Your role encompasses troubleshooting, case management, and delivering AV support for office events. You will own your cases from diagnosis through resolution, collaborating with colleagues and senior engineers when necessary. Come be part of a pioneering company in open-source software, where your passion for Linux and customer success can flourish.

About the Position Join us as we expand our dynamic team of Linux Engineers at Jane Street. We are in search of a dedicated leader who is passionate about technology and team development. Our team comprises diligent Systems Engineers, Administrators, and Programmers, all focused on maintaining and enhancing the platform that underpins Jane Street's production trading systems. (Learn more about the Linux Engineer role here). As a manager, you will lead by example. We expect you to support your team while also embracing the role of an individual contributor. Your journey will begin with a thorough understanding of Jane Street's technical landscape, allowing you to progressively transition into a management position. We value candidates who embody our principles: integrity, collaboration, intellectual curiosity, humility, and a data-driven approach to decision-making and problem-solving. Successful candidates will be Linux Engineers at their core, with experience in people management, project oversight, large-scale coordination, partnership development, strategic planning, and service delivery. About You The ideal candidate for the Linux Engineering Manager position will possess a robust technical background alongside substantial leadership experience. You should excel in leading through direct involvement, balancing individual technical tasks with leadership duties. A willingness to learn OCaml, our preferred programming language, is essential. The requirements are as follows: Bachelor's degree in Computer Science, Software Engineering, or a related technical field (or equivalent experience) Exceptional communication skills, capable of conveying ideas clearly in both small and large group settings, along with the ability to analyze and solve complex problems A proven history of supporting individuals and fostering team success Experience in cultivating and expanding partnerships across the organization Strong analytical and troubleshooting skills across various domains (technical, process, interpersonal) In-depth knowledge of operating system fundamentals, particularly Linux Proficiency with the Unix command line and shell scripting Hands-on experience with modern Linux systems and systems programming concepts Basic understanding of network protocols Programming experience in any language Fluency in English is required If you're a recruiting agency interested in partnering with us, please...

Why Join Deliveroo?At Deliveroo, our mission is to revolutionize how people shop and dine by seamlessly connecting consumers, restaurants, shops, and delivery riders. We strive to make food and product accessibility more convenient and enjoyable, empowering individuals to purchase what they want, when and where they desire.As a forward-thinking, technology-driven organization, we are leading the charge in one of the fastest-growing industries globally. Our small team is making a significant impact as we tackle some of the most fascinating challenges. We prioritize speed, autonomy, and innovative ideas, continuously seeking fresh perspectives.About the RoleIn the role of Senior Security Engineer, you will spearhead the development and implementation of security measures that safeguard our internal networks, workforce identities, endpoints, and corporate systems. Collaborating with security teams across the US, EU, and APAC, you will aim to minimize risk and enhance our security controls.Operating with significant independence, you will define the technical strategy, make architectural decisions, and oversee the execution of complex security projects from start to finish. Your focus will be on balancing risk mitigation with user experience, ensuring that security measures are effective without hindering employee productivity.This position emphasizes Identity and Access Management (IAM), Endpoint Security (EDR), Network Security, logging and detection engineering, and secure SaaS enablement. You will collaborate closely with IT, Legal, Privacy, Engineering, and business stakeholders to ensure that security is integrated as a fundamental practice across the organization.Our security protocols are aligned with recognized frameworks such as the CIS Critical Security Controls and the NIST Cybersecurity Framework (CSF).

Join Checkatrade as a Senior Security Engineer and play a pivotal role in safeguarding our systems and data. In this position, you will be responsible for designing and implementing robust security measures, monitoring potential threats, and ensuring compliance with industry standards. We seek a proactive individual who thrives in a fast-paced environment and is dedicated to continuous improvement.

Join Our Team as a Security EngineerAt incident.io, we are transforming incident response with our cutting-edge AI platform, dedicated to minimizing response times and enhancing reliability. Our comprehensive solution integrates on-call management, incident response, AI SRE, and status updates into one seamless platform, empowering teams to act swiftly, reduce outages, and keep their customers informed.Since our inception in 2021, we have successfully assisted over 1,500 organizations, including renowned names like Netflix, Airbnb, and Block, in managing over 500,000 incidents. Each month, thousands of engineers, product managers, and support staff rely on incident.io to restore services efficiently, maintain alignment during high-pressure situations, and focus on what truly matters.We are a rapidly expanding, ambitious team that values our customers, the quality of our product, and the magic we create together. With $100M raised from prestigious investors like Index Ventures, Insight Partners, and Point Nine, along with contributions from top executives in the tech industry, we’re poised for significant growth.Your RoleAs our inaugural Security Engineer, you will play a vital role in our product teams, ensuring application security is integrated from the foundational stages. Collaborating closely with engineers, you will identify vulnerabilities before they progress to production, mentor your peers on secure coding practices, and foster a culture where security is a primary focus.This position offers a unique opportunity to work at the intersection of security and engineering, contributing to the design and development of secure systems that align with our commitment to customer satisfaction.

At Menlo Security, we are dedicated to empowering secure connections, communications, and collaborations worldwide. Our mission has become increasingly vital in the current landscape shaped by COVID-19. We proudly serve a diverse clientele, including Fortune 500 companies, 9 out of the 10 largest global banks, and the Department of Defense.As we transition from a team of 400 towards our next growth phase, we seek passionate individuals who exhibit empathy and adaptability. The ideal candidate will possess a strong ethical foundation, exceptional organizational skills, and a commitment to service. A willingness to both give and receive constructive feedback is essential.Backed by industry-leading investors such as Vista Equity Partners, General Catalyst, JPMC, American Express, HSBC, and Ericsson Ventures, Menlo is poised for significant growth.Position Overview:The Senior Security Engineer will play a crucial role in safeguarding our organization’s digital assets, infrastructure, and data. Responsibilities include designing, implementing, and maintaining security systems and controls, managing security tools, conducting risk assessments, responding to incidents, and ensuring compliance with relevant security standards. This position involves close collaboration with various teams within Menlo to promote security best practices across all technological initiatives, thereby enhancing our security posture and resilience.Key Responsibilities:Security Operations & Monitoring:Oversee the SIEM platform and manage security alerts to identify, investigate, and respond to potential threats.Administer and optimize EDR solutions, specifically Crowdstrike, to ensure comprehensive endpoint protection.Lead incident response efforts, including investigation, containment, remediation, and post-incident analysis.Vulnerability & Risk Management:Oversee the vulnerability management program, including scanning, prioritization, and coordination of remediation efforts.Conduct risk assessments and formulate strategies for risk mitigation.