C# Developer | Software Engineering Practice at MARGO

About UsHarmattan AI is a pioneering defense technology company focused on developing autonomous and scalable defense systems. After successfully securing $200M in Series B funding, which values the company at $1.4 billion, we are actively expanding our teams to enhance our capabilities and deliver critical systems to allied forces.Our mission is driven by a commitment to creating real-world impact through technology, striving for excellence, setting ambitious objectives, and tackling the most challenging technical problems. We operate in a high-stakes environment where rigor, accountability, and execution are paramount.About the RoleAs a Software Engineer on the Ground Control Systems (GCS) team, you will be instrumental in developing our new line of drone controllers—high-performance, Android-based control stations tailored for professional UAV operations. Your role will involve extending and adapting the open-source QGroundControl platform (C++/Qt) to work seamlessly with our proprietary hardware, enhancing its features while ensuring reliability, performance, and scalability across various missions.ResponsibilitiesApp Development: Design, develop, and optimize our QGroundControl-based application utilizing C++ and Qt.Hardware Integration: Customize the application interface with physical controls (joysticks, buttons, switches, touchscreen) to provide a cohesive user experience.Feature Implementation: Transform user needs and mission requirements into actionable functionalities and UX/UI enhancements.Platform Maintenance: Port and maintain the application across different Android versions, ensuring optimal performance, compatibility, and security.Deployment: Oversee application updates and releases across our device fleet.Collaboration: Collaborate closely with embedded systems and electronics teams to facilitate smooth hardware/software integration, and partner with QA for field validation.

Segula Technologies is seeking a Control Engineer or Control Engineer Leader to join its Paris office. The role centers on designing and implementing control systems that drive performance and efficiency across various projects. Main responsibilities Develop control system solutions for both ongoing and new projects. Collaborate with cross-functional teams to help achieve project objectives. Use control engineering expertise to fulfill technical and project requirements. Work environment The team values fresh ideas and technical innovation. Daily work involves close collaboration and a focus on practical problem-solving.

Join the Innovators at AragoArago is a pioneering company at the forefront of artificial intelligence and semiconductor technology, dedicated to advancing the future through groundbreaking innovations.Established in 2024 by a team of visionary AI researchers and physicists, Arago harnesses expertise in photonics, electronics, software, mathematics, and machine learning. Our nimble team consists of talented engineers and scientists from leading global institutions.With a multicultural team representing nine nationalities, we operate from key hubs in France, North America, and Israel. We are passionate about exceptional science and rapid progress, guided by principles that define our culture:Deliver Excellence: We take pride in our work, ensuring it meets the highest standards.Speed of Execution: We value quick, decisive actions, progressing efficiently to achieve our goals.Collaborative Spirit: We work as one cohesive unit, fostering relationships built on trust and respect.Supported by leaders from major tech companies such as Apple, Arm, Nvidia, Microsoft, and Hugging Face, along with esteemed venture firms, Arago is poised to redefine the future of technology.

Join Contentsquare as a Software Engineer focused on streaming and data-intensive systems. In this role, you will design and implement high-performance solutions that handle large data flows, ensuring scalability and reliability. Collaborate with cross-functional teams to drive innovation and enhance our data processing capabilities.

Back Market is looking for a Senior Software Engineer focused on Order Management Systems to join the team in Paris. This position centers on developing and refining the platform to support a smooth experience for customers as they place and manage orders. Role overview This engineer will play a key part in building and maintaining scalable software solutions for order management. The work involves collaborating with colleagues from different departments to design, implement, and support features that improve how orders are handled across the platform. What you will do Contribute to the development and optimization of the order management platform Work with cross-functional teams to create and maintain scalable solutions Help ensure a seamless experience for customers managing orders Drive improvements and support ongoing innovation in order management processes Requirements Experience in software engineering, particularly with order management systems Ability to design, implement, and maintain scalable software Strong collaboration skills to work with multiple teams

About UsAt Harmattan AI, we are pioneering the development of autonomous and scalable defense systems. With a recent $200 million Series B funding round that has raised our valuation to $1.4 billion, we are poised for growth and are seeking talented individuals to join our mission of delivering cutting-edge systems to allied forces.Our guiding principles are centered around creating impactful technologies, striving for excellence, setting ambitious objectives, and confronting complex technical challenges head-on. We thrive in a dynamic environment where accountability, precision, and execution are critical.About the RoleWe invite a passionate Backend Software Engineer to become a vital part of our C2 Core team in Paris. In this role, you will be instrumental in developing the foundational architecture for our advanced tactical Command and Control (C2) application. You will operate in a high-stakes, technical environment where low latency, high availability, and secure data management are crucial.Your primary responsibilities will involve ensuring seamless data flow for real-time telemetry, high-bandwidth video streams, and mission commands between our fleet of robots and the internal C2 components, including the Common Operational Picture (COP) and Mission Planner. This system is designed for deployment on ruggedized tactical PCs in field environments often characterized by limited network connectivity.

Join the Arago TeamArago is at the forefront of innovation in AI and computer hardware, dedicated to advancing technology and shaping the future. Our mission is to catalyze breakthroughs at the intersection of artificial intelligence and semiconductor technology.Established in 2024 by leading AI researchers and physicists specializing in photonics, electronics, software, mathematics, and machine learning, Arago consists of a dynamic team of engineers and scientists sourced from prestigious companies and research institutions around the globe.With a diverse team representing nine nationalities and operational hubs in France, North America, and Israel, we thrive on exceptional science and rapid progress. Our guiding principles include:Deliver Excellence: We take pride in the quality of our work.Agility: We prioritize speed and efficiency in our processes.Team Synergy: We foster a collaborative environment built on trust and respect.Our esteemed team is supported by executives from industry giants such as Apple, Arm, Nvidia, Microsoft, and Hugging Face, alongside influential deeptech venture capitalists and successful founders.

Join Segula Technologies as a Project Manager specializing in Ground Liaison operations. In this dynamic role, you will be responsible for coordinating and managing projects that ensure efficient ground operations, collaborating closely with multidisciplinary teams to deliver innovative solutions.Your ability to oversee project timelines, budgets, and resources will be crucial in achieving our objectives. This is an exciting opportunity to contribute to cutting-edge projects in a vibrant industry.

Join our dynamic team at myjobcompany1 as a Lead Systems Engineer in Paris! In this pivotal role, you will lead the design, development, and implementation of innovative systems solutions that enhance operational efficiency. Collaborate with cross-functional teams to ensure project success and drive technological advancements.

Role overview Harmattan AI seeks an Embedded Software Engineer to join the Paris office. The focus is on building embedded solutions that enhance multimedia applications and user experiences. What you will do Design and develop embedded software for multimedia systems Work closely with team members from various disciplines to bring new concepts to life Contribute to maintaining high standards for software quality and performance Location This role is based in Paris.

Blockchain.com has grown into one of the largest cryptocurrency platforms, supporting over 90 million wallet holders and more than 40 million verified users since 2011. The company has handled over $1 trillion in cryptocurrency transactions, providing secure access to digital assets for millions worldwide. Role overview The Institutional team in Paris is seeking a Senior Software Engineer to help develop products and services tailored for institutional clients. Collaboration, clear results, and ongoing improvement shape the team’s approach to their work. What you will do Work with engineers and stakeholders to deliver software solutions for institutional clients Contribute to a high-performance team focused on innovation and efficiency Help refine processes and drive measurable outcomes Support a culture that values learning and team growth Requirements Professional experience as a software engineer, ideally in a similar setting Strong teamwork and communication abilities Openness to learning and adapting in a rapidly changing field Dedication to delivering dependable, high-quality software Location This role is based in Paris.

Join BlaBlaCar as a Senior System and Network EngineerBlaBlaCar, the world's foremost community-driven travel application, connects 27 million members annually for carpooling and bus travel across 21 countries. With a diverse team of 800 professionals from over 50 nationalities, we operate from five global offices, with 30% of our workforce thriving in fully remote roles.Your RoleAs a Senior System and Network Engineer within our IT Operations team, you will be instrumental in delivering robust IT services and solutions throughout our organization, ensuring efficiency and security. Your expertise will help streamline our network and software solutions, empowering our team members to perform at their best. You will work in close collaboration with both the Security and Engineering teams to uphold the integrity, availability, and reliability of our IT infrastructure.Reporting directly to Henry Marinho Faiacida, our IT Operations Manager, you will join a skilled team of six, comprising three IT Engineers and three Tech Support Experts.Key ResponsibilitiesIn this role, you will serve as a vital resource for knowledge, best practices, and the execution of technological innovations. Your main responsibilities will include:• Leading IT projects from inception to completion in collaboration with various engineering teams.• Setting up, administering, and maintaining IT SaaS systems and applications.• Reviewing and optimizing SSO workflows within SaaS platforms to ensure peak performance.• Keeping our infrastructure current by implementing security policies, patches, and necessary updates.• Partnering with the Security team to enforce security policies, permissions, and procedures.• Ensuring compliance across all hardware, including networking equipment, computers, IoT devices, and printers.• Taking responsibility for L2/L3 support troubleshooting within the IT Operations domain.• Communicating effectively with internal departments and stakeholders.Scope of Work:• Overseeing users' technical working environment across various development departments.

Join Our Mission to Transform Healthcare At Doctolib, we are on a mission to revolutionize the healthcare experience through cutting-edge technology. Our passionate tech team is dedicated to creating innovative products and features that enhance the daily lives of healthcare practitioners and their patients. Working in an agile environment, we collaborate closely with engineering, design, and business teams to achieve our goals. Your Role We are seeking a Senior Software Engineer to become a vital member of our Design System & Accessibility Team. Your contribution will be paramount in making Doctolib the leading digital and secure medical companion for patients. In our Platform domain, we focus on building and maintaining essential building blocks of our system with a "Platform as a Product" mindset. Our objective is to simplify the use of these complex components, allowing product teams to concentrate on their core mission: delivering faster solutions for healthcare professionals and patients. Why Your Work Matters: With a significant 80% of our traffic coming from mobile users, your role will be instrumental in bridging the gap between our Web and Mobile Design Systems, ensuring a seamless user experience across platforms. As part of the Frontend Platform team, you will empower all Doctolib Tech and Product teams to develop accessible, top-tier frontend applications. We achieve this by providing a robust web and mobile design system, creating supportive tooling, and offering guidance as Accessibility experts. Key Responsibilities: Design, build, and maintain a scalable web and mobile Design System using React and React Native to ensure consistent, accessible, and high-performance user experiences. Guide the convergence of Web and Mobile Design Systems, ensuring visual and functional consistency across React and React Native components. Develop and maintain React Native components for a seamless cross-platform experience. Mentor team members on React Native best practices, promoting a mobile-first culture within the Design System team. Collaborate with Product Designers to transform Figma designs into robust, reusable UI components, maintaining visual and functional parity between design and implementation. Advocate for accessibility (A11y), embedding inclusive design principles in our Design System and developing accessible components.

Join Alten, a leader in technology consulting and engineering, as an ADAS Systems Engineer (H/F) in Paris. You will play a pivotal role in the development of advanced driver-assistance systems, ensuring cutting-edge innovations in automotive safety and performance.

Join Alten as a Nuclear Control and Command Engineer (H/F), where you will play a vital role in ensuring the smooth operation and safety of nuclear facilities. This position offers the opportunity to work on innovative projects within the Energy & Environment sector, collaborating with a team of experts dedicated to advancing nuclear technology.

About UsAt MARGO, our consultants focus on what truly matters: complex projects that combine intellectual challenge with real business impact. We support leading players in finance, industry, and technology in designing and developing high-performance software solutions, including distributed architectures, cloud platforms, real-time systems, and large-scale critical applications.Why Join the Software Engineering Practice?You will be part of a team led by Paul Blois, Practice Manager at MARGO for 5 years, and Prosper Gratian, Practice Lead and C++ Developer. Working alongside them provides unparalleled insight into the company, close mentorship for your development, and the opportunity to contribute to demanding IT projects with significant impact for our clients.Your ResponsibilitiesYou will engage in the development of a core application for the front office of an investment bank, a booking tool that provides positioning and performs real-time risk calculations. This tool is essential for the trading floor and other data consumers such as risk management, accounting, and back office. You will be involved in:- Developing new features to enhance performance and reduce latency.- Optimizing code to ensure peak performance, particularly in multithreading and latency management.- Collaborating with front office teams and other client departments.Technical Challenges: Performance, multithreading, and latency management.Rich Functional Environment: You will work in a rich functional environment, interacting with several key departments.Tech Stack: C++ 17

Join Alten as a Linux System Engineer in Paris, where you will be at the forefront of technology, driving innovations in system architecture and operations. This role requires a passion for Linux systems and a desire to work in a collaborative environment.You will be responsible for designing, implementing, and maintaining Linux-based systems to ensure optimal performance and security. Collaborate with cross-functional teams to identify and resolve system issues, implement automation solutions, and enhance overall system efficiency.

Arago operates at the intersection of artificial intelligence and semiconductor technology, drawing on the expertise of AI researchers, physicists, and engineers. With a multicultural team from nine countries and offices in France, North America, and Israel, the company brings together experience in photonics, electronics, software, mathematics, and machine learning. Arago is supported by industry leaders and investors from organizations such as Apple, Arm, Nvidia, Microsoft, and Hugging Face. The Paris-based System Administrator and Infrastructure Engineer ensures that Arago's technical environment remains reliable and scalable. This position supports both daily IT operations and larger infrastructure projects, working closely with the engineering team to enable rapid progress and high-quality results. Main responsibilities Cloud Prototyping: Maintain and monitor the Beta Cloud Service so external partners can access prototype technology. Hardware Acquisition: Source and install new hardware, including storage solutions, high-performance computing systems, and networking equipment. System Monitoring: Design and maintain monitoring systems for all internal servers and services, aiming for 99.9% uptime. Tooling Initiatives: Lead projects to develop internal tools that improve engineering productivity. Onboarding Process: Oversee IT onboarding by provisioning workstations and laptops (macOS, Windows, Linux) and automating account management. Live Support: Provide helpdesk support during working hours for both the Arcueil office and remote teams. Work environment Based in Arago's Paris offices Collaborate with a diverse, international team Support a culture focused on quality, rapid progress, and close teamwork

At Joko, we empower consumers to shop smarter and save money. Our mission is to transform the shopping experience, enabling individuals to make informed decisions about their purchases.Founded in Paris, Joko is a tech-driven company and a certified B Corp, boasting over 90 talented employees across Paris, Barcelona, New York, and beyond. Over 5 million users benefit from our services, saving money daily at more than 10,000 merchants through our platform.We offer a range of features, from cashback and automatic coupons to price alerts and carbon tracking, continually enhancing our products to facilitate smarter shopping. Currently, we are developing an AI-powered shopping assistant to help users identify the best products based on price, quality, and impact.Having achieved profitability in our primary market, we are now expanding globally, with a keen focus on the US market.Join us at the forefront of the shopping revolution! Our Engineering TeamOur Engineering team thrives on tackling advanced technical challenges with innovative solutions. With a strong emphasis on product design and innovation, they are shaping the future of shopping. Their goal is to positively influence the everyday lives of millions of users worldwide.As a member of the Engineering team, Software Engineers collaborate closely with the Product team throughout the entire process—from exploration and design to implementation and deployment. At Joko, we understand that teams composed of engineers with diverse skill sets, working in tandem with product teams, can deliver a truly delightful and innovative user experience.The Engineering team is rapidly expanding to continuously innovate across all facets of our product and technology stack, driving the transformation of online shopping. Your RoleAs a Growth Software Engineer, you will play a crucial role in scaling Joko's user and business growth through your coding expertise. Collaborating closely with the Product team, you will iterate quickly on key growth drivers—such as acquisition, retention, and engagement—as we expand into international markets, beginning with the US.You will work at the intersection of product and engineering, propelling the business forward within a dedicated cross-functional task force that includes key members from Marketing, Data, Business, and Product.Growth Experimentation: You will design, build, and deploy experiments across the entire user journey—from onboarding to retention—to drive significant results in key growth metrics.