Senior Software Engineer - React & Java

believe is hiring a Senior Software Engineer with a focus on React and Java for its Paris office. This role centers on creating web applications that deliver effective user experiences. Key responsibilities Design and build web applications using React and Java Collaborate with colleagues across different teams to understand requirements and deliver solution…

nexton is looking for a Fullstack Java / React Developer based in Paris. This position centers on developing and refining applications using both Java and React. Collaboration with colleagues from various teams is a key part of the job, with a focus on creating user-friendly interfaces and enhancing the overall user experience. What you will do Design and build applications with Java and React Work alongside cross-functional teams to develop interfaces Offer ideas to improve usability and boost user satisfaction Requirements Experience with backend development in Java and frontend work in React Interest in tackling complex problems with creative solutions Ability to thrive in a collaborative and evolving environment

Join our dynamic team at Altersolutions as a Senior Software Engineer specializing in Java Spring Boot. We are seeking a highly skilled and motivated individual who thrives in a fast-paced environment and is eager to take on challenging projects. In this role, you will be responsible for designing, developing, and maintaining robust software applications that meet our clients' needs.

Join our dynamic team at Alten as a Fullstack Java / React Developer (H/F). We are looking for passionate developers who thrive in innovative environments and are eager to work on exciting projects that push the boundaries of technology.

Your Impact Join Doctolib, a rapidly expanding healthcare technology platform, as we seek talented Frontend Software Engineers in Paris. We welcome developers at all stages of their careers, from newcomers to seasoned professionals, to join our innovative Engineering teams! As a Frontend Software Engineer, your role will be crucial in enhancing Doctolib's mission to provide high-quality products that benefit both patients and healthcare professionals. Your contributions will help solidify our position as a leader in the healthcare technology sector. Your key responsibilities will include: Collaborating with product managers, designers, and fellow engineers to develop features that provide real value to our users. Designing, developing, and maintaining React and TypeScript components while adhering to performance, accessibility, and scalability standards. Enhancing code quality through thorough testing, meticulous documentation, and constructive code reviews. Sharing your expertise and working collaboratively across teams to continuously advance Doctolib's frontend architecture. Life at Doctolib Tech Our solutions are built on a fully cloud-native platform that caters to both web and mobile applications, supports multiple languages, and is tailored to various healthcare specialties. Our technology stack includes Rails, TypeScript, Java, Python, Kotlin, Swift, and React Native. We ethically leverage AI across our products to empower patients and health professionals. Learn more about our AI vision here. Curious about our tech culture and working environment? Visit the Doctolib Tech site.

Join our innovative team that is transforming the future of global living.At The Flex, we envision a world where renting a home is instant, intelligent, and seamless—much like booking a ride. Our mission is ambitious: to empower anyone to live anywhere, anytime, without hassle.Driven by Base360.ai, our unique automation engine, we are crafting the operating system for modern renting—integrating property data, streamlining operations, and facilitating smooth stays across continents.If you are passionate about complex systems, automation, and developing software that has real-world applications, this position offers you the opportunity to take ownership and make a significant impact. What You'll CreateAs a Senior Software Engineer, you will design, develop, and scale essential components of The Flex platform—from core services and APIs to automation workflows and real-time systems.You will work with considerable autonomy, managing problems from start to finish and directly influencing architectural decisions while remaining deeply engaged with production code.This role is for engineers who prioritize impact over meetings and take pride in constructing systems that are reliable, elegant, and scalable. Your ObjectivesDevelop Core SystemsCreate and maintain scalable services that enhance bookings, payments, availability, pricing, and guest experiences.Design Robust APIsEstablish clean, well-structured APIs that connect Base360.ai with internal tools and external partners.Automate OperationsConstruct event-driven workflows that eradicate manual tasks and unlock operational efficiencies.Deploy with AssuranceImplement and manage cloud-native infrastructure on AWS with an emphasis on reliability, security, and performance.Tackle Meaningful ChallengesEngage in real-time booking synchronization, pricing intelligence, keyless access systems, AI-driven alerts, and live operational dashboards.Collaborate for SuccessPartner closely with product, data, and operations teams to transform complex requirements into straightforward, effective systems. Ideal Candidate ProfileExtensive experience in building production systems with Node.js, React, and AWS.Solid understanding of software design principles and best practices.Proficient with CI/CD practices and tools.Strong communication skills and a collaborative mindset.

Join nexton, a leading company in the Telco Media Transport sector, as a skilled Java / React Developer. In this role, you will leverage your expertise to develop and maintain robust applications, collaborate with cross-functional teams, and contribute to innovative solutions that enhance user experiences.

Your Role Join our dynamic Preventive & Continuous Care Companion team as a Senior Software Engineer at Doctolib. Your expertise will be pivotal in reinforcing our commitment to being a continuous health partner for our users by crafting top-notch free and premium products that drive health goal achievement through tailored recommendations. Key Responsibilities: Collaboratively design, implement, and uphold high-quality solutions that deliver significant value to our users. Adopt best practices to sustain and elevate engineering standards and operational excellence, facilitating team member success. Proactively oversee system health within your team’s domain by measuring SLIs, defining SLOs, and enhancing alert mechanisms. Continuously expand your domain knowledge while influencing cross-team collaborations to manage dependencies and alleviate uncertainties. Offer constructive feedback during pair programming sessions to foster growth and innovation. Our Technology Landscape We utilize a unified, fully cloud-native platform that caters to web and mobile interfaces, supports multiple languages, and meets local healthcare requirements. Our focus on modular architecture allows us to create reusable components within a distributed framework. Our technology stack includes Rails, TypeScript, Java, Python, Kotlin, Swift, and React Native. We also ethically integrate AI across our products to empower both patients and healthcare professionals. Explore our AI vision here and learn about our inaugural AI hackathon here! Who You Are If you feel that this opportunity aligns with your skills and aspirations even if you don't meet every requirement, we encourage you to apply! Deep understanding of the JVM ecosystem (Java, Kotlin, Spring Boot). Familiarity with Domain Driven Design principles. Proponent of pair and mob programming methodologies. Product-oriented mindset, adept at guiding teammates in balancing business needs and technical constraints. Experience in monitoring system health and actively contributing to its enhancement.

Role Overview Sopra Steria is seeking a Tech Lead with expertise in Fullstack Java and React for its Financial Services practice in Paris. This role guides a team of developers, shaping software solutions that support client objectives and business needs. Main Responsibilities Lead and coordinate a team of developers on fullstack Java and React projects Mentor junior team members and support their technical growth Work closely with cross-functional teams to deliver efficient, reliable software Promote best practices in coding standards and project management Contribute to the delivery of high-quality solutions for financial services clients What We Look For Significant experience with Java and React in a fullstack environment Strong leadership and team coordination skills Ability to mentor and guide junior developers Experience collaborating with diverse technical and business teams Location Paris, France

Main ResponsibilitiesDesign, develop, and maintain backend applications using Java (Spring Boot).Define, implement, and optimize event flows on Apache Kafka (topics, partitions, performance, security).Participate in software architecture decisions and the industrialization of real-time solutions.Ensure code quality through unit tests, continuous integration, and code reviews.Contribute to the deployment and monitoring of applications (CI/CD, monitoring, support).Collaborate closely with Product, Data, and Infrastructure teams.Provide insightful suggestions for improving technical and methodological best practices.

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 the Success Story of TheodoSince its inception in 2009, Theodo has been at the forefront of helping innovative businesses design, develop, and deploy ingenious digital products, leveraging cutting-edge technology and Lean methodologies.Our distinctive approach is anchored on three core principles:- We have honed recognized expertise in key product design and development technologies;- Regardless of the project stage, delivering value to our clients is our foremost priority in every decision;- We attract top digital talent and nurture their ingenuity through a Lean approach.Theodo has experienced remarkable growth over the past 15 years, bringing together more than 700 passionate Software Engineers dedicated to technology and continuous improvement. As we expand, we have structured our teams into specialized entities focused on technology (Theodo Apps, Theodo Cloud, Theodo Data & AI) and industries (Fintech, Govtech, Healthtech, Consumer Products). By 2025, Theodo aims to achieve €100M in revenue.You will become part of Theodo Extend, a newly formed entity within Theodo, designed to meet a growing market demand: many clients wish to retain control over product management while integrating top-tier developers into their teams.In 2024, we collaborated with over 100 clients, including Carrefour, Dior, and Yves Saint Laurent, with 63 experts dedicated to these projects.Your Mission:As a Software Engineer at Theodo Extend, you will be fully integrated into a client team while enjoying the support of our community of passionate engineers. You will receive training in best practices and ongoing guidance.You will work on tasks such as:- Revamping an existing codebase to ensure reliability, maintainability, and scalability through a complete migration to a modern stack.- Deploying a V1 in a matter of weeks, even in high-pressure contexts.

About Air Apps Air Apps is a family-founded company focused on developing the world's first AI-powered Personal & Entrepreneurial Resource Planner (PRP). Since our start in 2018 in Lisbon, we have grown to operate in both Lisbon and San Francisco. Our apps have reached over 100 million downloads worldwide, all while remaining self-funded. We challenge standard approaches and aim to build AI-driven solutions that make a difference for people everywhere. Creativity and long-term thinking guide our work as we build products that empower individuals globally. React Engineer , Paris (On-site) We are building our talent pool for a future opening for a React Engineer in Paris. This role focuses on creating responsive, accessible user interfaces for our web applications. The position is fully onsite at our Paris office, where close collaboration with designers, product managers, and backend engineers is part of daily work. We are open to supporting relocation for the right candidate. What You Will Do Build and maintain user interfaces using React for our web products Translate wireframes and prototypes into stable, scalable front-end experiences Work closely with cross-functional teams to deliver seamless user experiences Next Steps This listing is to connect with talented engineers as we prepare to post the official position. We will reach out once the job is formally open.

Role Overview Sopra Steria is looking for a Fullstack Java React Developer to join the team in Paris. This role focuses on building and maintaining applications for clients in the financial services sector. Projects aim to support digital transformation and improve user experiences. What You Will Do Work with cross-functional teams to design, develop, and maintain applications Use both front-end and back-end technologies to deliver software that meets client requirements Contribute to the development of solutions that support business goals in financial services Location This position is based in Paris, Île-de-France.

nabla is looking for a Senior Front-End Engineer with deep experience in React to join the Paris office. This position centers on building web applications that are both dynamic and user-friendly, with a strong focus on delivering a polished user experience. Role overview Work closely with colleagues across disciplines to design, develop, and refine the front-end architecture. The goal is to ensure applications remain fast, responsive, and reliable. Day-to-day, expect to collaborate with product and design teams to translate ideas into seamless interfaces. What you will do Develop and optimize React-based web applications for performance and usability Work with cross-functional teams to implement new features and improvements Guide junior developers and help set coding standards, testing procedures, and deployment practices Impact This role shapes the quality of nabla’s products and directly influences customer satisfaction. Senior engineers here play a key part in mentoring others and establishing best practices across the front-end team.

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 Altersolutions as a Tech Lead specializing in React to lead innovative projects from conception through execution. You will be responsible for guiding a talented team of developers, ensuring best practices in coding and design, and delivering high-quality software solutions. Your role will involve collaborating with cross-functional teams, mentoring junior developers, and driving the technical vision of our projects.

Join Talan as a Senior Java Tech Lead in our dynamic Engineering & Development IT department. In this pivotal role, you will lead innovative projects, mentor a talented team of developers, and drive the adoption of best practices in software development. Your expertise in Java and leadership skills will be essential in delivering high-quality solutions that meet our clients' needs.

At Swile, we are committed to enhancing professional experiences through innovative product solutions that alleviate daily challenges and elevate employee satisfaction. Our cutting-edge offerings in Fintech, Travel, HR, and Employee Benefits serve over 5.5 million users across 85,000 companies in France and Brazil, making a significant impact on the workplace.As a Senior Software Engineer, you will play a pivotal role in problem-solving, blending creativity with technical expertise. Your focus will be on delivering high-quality solutions swiftly and effectively, addressing both business and engineering challenges with innovative strategies rather than being restricted to specific technologies.

About H H focuses on advancing superintelligence through agentic AI. The company’s mission centers on automating complex, multi-step tasks that people usually handle, aiming for AI agents to help realize the full range of human potential. H seeks talented AI professionals who care deeply about responsible and safe development, as well as technical progress in agentic systems. The culture values openness, ongoing learning, and teamwork. Every team member’s input matters here. Product Engineering at H The Product Engineering team develops H’s Enterprise Platform, which provides customers with tools and services for essential operational needs. This platform supports large-scale computer-use agents, manages complex workflows, and offers a suite for observability, troubleshooting, and evaluation. Product Engineering connects AI research with practical applications and works closely with teams across the company.