C# .NET Developer - Back-End / Full-Stack (H/F)

Join our dynamic team at Magellan Partners as a Full Stack Java Developer! In this role, you will be responsible for designing, developing, and maintaining innovative software applications using Java technologies. You will work collaboratively with cross-functional teams to deliver high-quality solutions that meet our clients' needs.As a Full Stack Developer, you will leverage your expertise in both front-end and back-end development to create user-friendly applications. This is an exciting opportunity to enhance your skills and contribute to impactful projects in a fast-paced environment.

Your Responsibilities :As a Java JEE Developer / Software Engineer (H/F), you will collaborate with an agile team to drive back-end or full-stack development for one of our esteemed clients, focusing on:Analyzing architecture to ensure improvements meet expectations.Developing analytical tools for delivered components.Creating new features on a new platform compatible with current architecture.Automating testing procedures.Additionally, you will be involved in:User demonstrations.Integration testing.Production delivery (coordinating with infrastructure and security teams).Web and server development (NGINX, Apache, Tomcat, ...).Production and operational deployment procedures.Continuous integration (Jenkins, GitLab, Bitbucket, ...).Continuous deployment (Ansible, AWX, Octopus, GitLab, ...).Creating and participating in test cases.

Join Margo Group as a Full Stack Developer specializing in Java and React. We are seeking a talented and motivated individual to contribute to our innovative projects and help shape the future of our tech solutions. As part of our team, you will work closely with designers and product managers to refine our offerings and deliver high-quality software solutions.

Join our team as a Java Angular Developer for a Banking Project (H/F)Location: Villejuif (78)Remote Work: 3 days a weekContract Type: CDISalary: Starting from €45,000Start Date: ASAPRequired Experience: Minimum 4 yearsMain Responsibilities:Design, develop, and maintain full-stack web applications.Engage in technical analysis and solution design.Create RESTful services and APIs.Contribute to both front-end and back-end application development.Participate in code reviews to ensure development quality.Address issues and optimize application performance.Assist in deploying and operating applications in a containerized environment.Contribute to monitoring and managing applications in production.Collaborate with project teams in an Agile setting.

En tant que Développeur Full Stack Junior chez everience, vous aurez l'opportunité de contribuer au développement d'applications web en utilisant des technologies modernes telles que Java et Angular.Vous collaborerez avec une équipe d'experts pour concevoir, développer et déployer des fonctionnalités innovantes qui répondent aux besoins des utilisateurs.Vos principales responsabilités incluront la participation aux phases de conception, le développement de nouvelles fonctionnalités, ainsi que la réalisation de tests unitaires et l'intégration continue. Vous aurez également l'occasion d'explorer d'autres technologies et outils en développement Full Stack.Missions :Contribuer à la conception et à la planification des fonctionnalités.Développer des fonctionnalités front-end et back-end à l'aide de Java et Angular.Participer aux tests unitaires et aux processus d'intégration continue.Collaborer avec l'équipe pour résoudre des problèmes et optimiser les performances.Maintenir une documentation claire et à jour sur le développement et les processus de déploiement.Rester informé des dernières tendances et évolutions technologiques.

Join our dynamic technical team of around thirty professionals in a warm and fun work environment! You have the freedom to choose your preferred workstation setup, allowing you to work in the way that suits you best.Your day-to-day will involve tackling a diverse range of challenges, including API development, implementing new features, creating proofs of concept (POCs), and managing application maintenance (TMA).Our technology stack includes:NodeJs & ExpressJS;AngularJs, VueJs;MongoDB, Postgres;Kubernetes & Docker;AWS;

Company Overview:Tessan is a fast-growing French startup specializing in telemedicine, dedicated to combating medical deserts across France. With over 1,500 devices deployed in less than six years, our mission is to ensure that every French citizen can access a doctor within 15 minutes of their home.We are expanding our team to support our product growth and accelerate our technological projects in web, mobile, data, and AI solutions. We are looking for a Full Stack Developer Intern (H/F) to join our technical team and actively contribute to the development of our digital solutions.Key Responsibilities:In a context of rapid product growth and technological innovation, you will participate in developing and enhancing our applications and services. You will collaborate with the technical team on various topics ranging from product development to optimizing our data and AI tools.1) Product Development (Web & Mobile)Engage in continuous development of the Tessan mobile and web applicationsContribute to the creation of new features (front-end & back-end)Assist in bug fixing and ongoing improvements of the applications2) Service Maintenance & ImprovementParticipate in maintaining the backend services and APIsContribute to enhancing performance and stability of servicesHelp establish best development practices (testing, code quality, documentation)3) Optimization & AutomationAssist in optimizing technical and operational processesParticipate in automating workflows (data handling, synchronization, processing)Utilize AI tools to improve productivity and development efficiency4) CI/CD, Deployment & IndustrializationContribute to improving CI/CD pipelinesAssist in deploying and industrializing new projectsHelp implement monitoring tools and service tracking5) Architecture & Technical ProjectsEngage in architectural discussions (mobile, web, backend)Enhance skills on technical choices and best development practicesContribute to data-related projects, data pipeline, and topics around Big Data and AI as projects progress6) Cross-Department CollaborationWork collaboratively with product, operations, and business teamsParticipate in technical discussions and progress meetings with the team

Sopra Steria is seeking a Java Full Stack Developer to join its team in Paris, focusing on projects within the financial services sector. This position centers on building and maintaining applications that support the changing requirements of clients in finance. Role overview This role involves contributing to the design and development of software solutions using Java and related technologies. Projects aim to address real-world challenges faced by financial institutions. What you will do Develop and enhance full stack applications for financial services clients Collaborate with team members to deliver solutions that align with client needs Apply technical expertise to ensure applications are reliable and effective Requirements Experience with Java development Ability to work on both front-end and back-end components Interest in financial services projects Based in or able to work in Paris, Île-de-France

Who are we?At MARGO, our consultants focus on what truly matters: tackling complex projects that combine intellectual challenges with real business impacts. We support major 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 five years. Working alongside them means benefiting from in-depth company knowledge, receiving close support for your career development, and contributing to demanding IT projects with significant impact for our clients.Your Responsibilities- Design, develop, and optimize a new web application for the reporting, tracking, and auditing of insiders (staff with access to sensitive information) for a major banking client.- Participate in defining and implementing a high-performing and scalable architecture.- Address performance optimization challenges in both front-end and back-end systems.- Ensure code quality, maintainability, and security of the solution.- Collaborate closely with product, security, and infrastructure teams for seamless integration.- Contribute to code reviews, continuous improvement, and the sharing of best practices.Languages: Java 17, TypeScriptAssociated frameworks and technologies: Spring Boot, Angular 12, Git, CI/CDChallenges: performance, response time optimization, robustness, and regulatory complianceDesired ProfileWe are looking for a full-stack developer who is passionate about real-time systems and interested in financial markets, eager to work in complex and high-performance environments.- Education level: Master’s degree (engineering school or university).- Strong skills in both back-end and front-end development, multithreading, performance optimization, and good development practices (SOLID, unit testing).- Experience in developing critical systems, real-time data stream processing; experience in finance is a plus.- Ability to solve complex technical problems.

Join Alten as a Full Stack Developer specializing in Vue.js and PHP Laravel. We are seeking passionate developers who thrive in innovative environments. You will work on exciting projects that challenge your skills and allow you to grow professionally.

Join our innovative team at myjobcompany1 as a Full Stack Web Developer. In this role, you will be responsible for designing and implementing robust applications that improve user experience and meet business needs. You will work with both front-end and back-end technologies, ensuring seamless integration and performance.

About UsAt CryptoNext Security, we are pioneers in the realm of deep technology, focusing on post-quantum cryptography. Our innovative solutions empower businesses and institutions to safeguard their data against the impending challenges posed by quantum computing. We proudly collaborate with prominent clients across sectors such as finance, defense, and telecommunications.Your Daily ResponsibilitiesCraft and implement dynamic user interfaces utilizing React for our advanced post-quantum cryptography products.Work collaboratively with Product and Backend teams to deliver a seamless and user-friendly experience.Enhance performance while ensuring cross-browser and cross-device compatibility.Integrate REST APIs to facilitate interaction with backend services.Engage in code reviews and uphold best practices, including unit testing, continuous integration, and comprehensive documentation.Propose enhancements to frontend architecture through technological upgrades and refactoring.Foster improvements in our products beyond your typical responsibilities.Adhere to our frontend team principles: “Done over perfect” / we prioritize speed: KISS, DRY (Don't Repeat Yourself), SOLID.Essential SkillsProficient in React / Next.js along with its ecosystem (React Hooks, Context API).Solid understanding of TypeScript and fundamental programming principles.Experience with modern UI libraries such as Tailwind or chadcn/ui.Proven track record in integrating REST APIs.Strong knowledge of frontend performance optimization and related tools (Webpack, Vite, Core Web Vitals).Familiarity with frontend testing frameworks like Jest, React Testing Library, and Cypress.Competence in Git, CI/CD pipelines, and DevOps for automated integration and deployment.Desirable SkillsExperience with gRPC.Understanding of secure coding practices and application security.Basic knowledge of cryptography and cybersecurity.Experience in a startup or deeptech environment.Join Our TeamYou will become a key member of our R&D team, collaborating closely with backend developers, product managers, and UX/UI designers. You will report to the team lead and work with various departments to develop high-performance, user-centric interfaces that align with our clients' needs.Application ProcessInitial conversation with our HR team to discuss your background and motivations.Technical interview to assess your skills and fit for the role.

UpSlide is the leading productivity and branding solution for financial services. Our innovative software significantly enhances the functionalities of PowerPoint, Word, Excel, and Power BI, enabling users from prestigious firms such as Citi, KPMG, and BNP Paribas to focus on high-value tasks rather than formatting or manual data entry. With over 160 employees, we are in a growth phase, with offices located in Paris (headquarters), London, New York, Singapore, and Berlin.Our Core Values Our values guide our approach to work and are central to our recruitment process. We seek individuals who resonate with the following principles:Excellence: Every detail matters, and we prioritize the quality of our deliverables.Trust: We are passionate, committed, and empowered to act autonomously.Well-being at Work: We maintain a positive outlook and share our enthusiasm with colleagues and clients alike.The Team ‍‍You will join the UpSlide development team, currently composed of 26 developers organized into 5 squads. Our missions for 2026 include:OfficeJS: Preparing UpSlide for the transition from Microsoft Office to Office JS.FA: Enhancing our product's superiority in the Financial Advisory sector.FA & AI: Strengthening our product's edge in Financial Advisory by focusing on AI-related solutions.IB & AM: Continuously improving our offerings for Investment Banking & Asset Management.Platform: Upgrading our infrastructure to support tenfold user growth.Join Us!

About UsCryptoNext Security is a pioneering deeptech startup focused on post-quantum cryptography. We empower institutions and enterprises to navigate a future where quantum computing poses a threat to existing cryptographic standards. Our collaborations span major sectors including finance, defense, and telecommunications, as we deliver state-of-the-art, quantum-safe security solutions.Your RoleIn your capacity as a Full Stack Developer, you will play a key role in advancing DISCOVERY, our innovative observability and orchestration platform tailored for post-quantum cryptography operations.You will engage with the entire technology stack — developing backend services, managing data flows, and crafting frontend interfaces — while working closely with product, backend, and infrastructure teams.Responsibilities Design, develop, and maintain comprehensive full-stack features for the DISCOVERY platform. Create modern, responsive React front-ends that integrate seamlessly with Node.js and Kafka backends. Participate in architectural discussions and propose technical enhancements in line with our long-term product vision. Backend Development & APIs Design and implement efficient REST and event-driven APIs. Ensure optimal performance, scalability, and resilience across distributed components. Collaborate with backend engineers on domain modeling, API contracts, and data flows. Data Visualization & Observability Implement advanced data visualization and monitoring features using the ELK stack (Elasticsearch, Logstash, Kibana). Integrate backend logs, metrics, and analytics into user-friendly frontend dashboards. Engineering Standards Engage in code reviews and maintain high standards of engineering excellence. Contribute to technical documentation and advocate for software craftsmanship. Adhere to the KISS, DRY, SOLID principles, and embrace pragmatic engineering methodologies (“done is better than perfect”). DevOps & CI/CD Assist in deployment workflows, CI/CD pipelines, and automation initiatives. Work within Docker/Kubernetes environments to ensure smooth delivery of applications.

Role Overview Talan is hiring a .NET Developer with full stack experience and strong Azure DevOps skills for its Paris office. This position involves designing, building, and deploying software solutions that support client operations. The role works within an agile framework and involves close collaboration with colleagues from various disciplines to deliver reliable products.

Join our innovative team at Meritis as a Java Angular Developer (H/F) in the heart of Paris! We are looking for a passionate and skilled developer who thrives in a dynamic environment and is eager to contribute to exciting projects. You will be responsible for developing robust applications using Java and Angular, collaborating with cross-functional teams to deliver high-quality software solutions.

Job Overview:We are seeking a talented Java AWS Developer with a strong OPS inclination to join one of our esteemed clients in the transportation sector. This role involves participating in the redesign of one of their strategic tools. You will have the opportunity to:Engage actively in team dynamicsParticipate in various SCRUM ceremoniesTake ownership of your tasksMaintain the team's toolsDeliver high-quality outputs while managing project costsEstimate workload and task complexities for ongoing developmentsFollow agile practices for deliverables, including Java development, unit testing (TDD), and automated functional testing (BDD)Communicate alerts and progress on tasksContribute to the team's technical architecture studiesEnsure smooth deployment of releases and handover to client teamsMeet acceptance criteria for releasesProvide high-level support for operational issues encountered during production or ongoing operationsTechnical Environment:Java/J2EESpring BootKotlinAWSREST/SOAPJenkinsAgile methodologies, BDDAre You Ready to Join Us?If you are eager to be part of a learning organization committed to your professional development and personal projects, then Apside Paris is the place for you!

Join Altersolutions as a Java Angular Developer H/F, where you will be part of a dynamic team tasked with developing innovative web applications. We are looking for someone with a passion for technology and a strong foundation in Java and Angular frameworks.

Join Alten, a leading technology consulting company, as a Java/Angular Developer. In this exciting role, you will be responsible for designing and developing innovative web applications that enhance user experiences. You will collaborate with cross-functional teams to deliver high-quality software solutions while adhering to best practices in software development.