Backend Engineer

• Co-architect scalable and efficient backend systems using Python.
• Work hand in hand daily with the AI Operations team to deliver integrated solutions connected to frontend components in proofs of concept, product components, and customer-facing products, and with a modern cloud-native infrastructure platform.
• Collaborate with cross-functional teams including Product Managers, backend and frontend engineers, and AI Engineers to deliver high-quality backend solutions powering high-impact features.
• Ensure high standards of code quality and security, with a strong emphasis on automated tests and Domain-Driven Design.
• Participate in API design, implementation, and documentation for both internal APIs and those exposed to third-party integrators.
• Keep up to date with evolving standards to advise on and propose upgrade plans.
• Your work will contribute to the creation and optimization of innovative CCaaS tools and processes.

Middle Python Backend Engineer – Virtual Agent AI Team

• Design and develop BFF (Backend-for-Frontend) services
• Optimize performance through cache management and data flow handling
• Contribute to continuous integration and deployments
• Produce robust, maintainable code that adheres to standards

Senior Backend Node.js BFF Developer

• develop any part of the TypeScript code, even outside your scope
• lead the technical architecture of cross-functional projects while taking into account the constraints of different scopes and teams
• review Pull Requests outside your team’s scope (JS stack)
• handle any bug across the entire JS stack, even outside your scope
• collaborate with other teams
• anticipate and account for the impact of features and technical choices based on the constraints of other teams
• introduce substantial and impactful improvements to the codebase (development best practices, refactoring)
• mentor junior developers (IC1, IC2, IC3) on one’s own team and occasionally outside of one’s team

Senior Backend JS Developer – CDI

• Contribute to defining business requirements
• Estimate and design technical solutions
• Implement technical solutions
• Deliver high-value business features on a regular basis
• Analyze and fix defects
• Participate in the validation of delivered developments (unit tests, code reviews)

Java Back-End Developer

• Collaborate with the AI Tools squad to implement and improve AI features.
• Design and architect new features, chaining a mix of internal and external services.
• Monitor and scale the growing load on the FastAPI service.

Senior Software Engineer – FastAPI, Async Python

• Design, develop, and maintain backend services and APIs using Ruby on Rails.
• Implement new features for the SaaS platform, write clean and maintainable code, and ensure the scalability and performance of the application.
• Contribute to backend architecture decisions, improve system scalability, and optimize database queries and search performance using Elasticsearch.
• Collaborate with product, frontend, and DevOps teams to deliver high-quality features.
• Participate in code reviews, maintain testing standards, contribute to CI/CD processes, and support best engineering practices within the team.

Senior Backend Developer

• As a Python Back End Developer, you will be responsible for developing the backend of our EDR
• Contributing to the construction and improvement of the product by adding new features, from conceptualization to code implementation
• Addressing performance issues: the backend must handle and process data from 100,000 machines, so the code must be efficient
• Ensuring the reliability of the backend, which is installed on-premise at our clients and needs to operate autonomously
• Contributing to internal tooling to make the development process as seamless as possible
• Providing input on areas of improvement in the existing codebase.

Backend Python Engineer – Cybersecurity

• Develop new features
• Maintain the platform
• Contribute to technical decisions
• Perform testing phases

PHP Developer

• Develop new features
• Direct contribution to the product
• Participate in team rituals
• Take part in architectural decisions and define best practices
• Contribute to technical strategy and long-term vision
• Review code and ensure technical quality
• Support the team's skills development
• Define and track objectives
• Lead and coordinate the team's day-to-day activities

Lead Back-end Developer

• Understand business needs and propose appropriate technical solutions
• Design and develop new features in a .NET / C# environment
• Participate in the evolutionary and corrective maintenance of existing applications
• Ensure the performance, reliability and optimization of processes
• Perform technical tests and ensure the quality of developments
• Write technical documentation for implemented solutions
• Collaborate with technical and functional teams to ensure the overall quality of deliverables

Software Engineer / .NET Developer, Angular

• Design, develop, and maintain highly performant, scalable, and secure applications
• Collaborate directly with Product Managers to understand requirements and deliver solutions
• Work closely with the Infrastructure team for optimization and troubleshooting
• Lead by example in writing clean, well-documented, and testable code
• Mentor and guide junior developers

• Architecture overhaul, greenfield development, and modernization of a public information system or B2B platform
• Collaboration with client teams or on internal projects
• Participation in technical decisions, product vision, and craft culture (TDD, DDD, Clean Architecture…)

Java Consultant

• Design and develop fullstack applications using .NET (Core/6+) and Angular, following Clean Code practices and SOLID principles
• Optimize back-end application performance (SQL queries, stored procedures, Entity Framework ORM) and ensure application security (OWASP standards)
• Participate in the complex redesign of the GAME application, collaborating with business and technical teams
• Industrialize DevOps processes: CI/CD (GitLab), unit and integration testing, code reviews
• Collaborate in an Agile (Scrum) environment to deliver high-value features while meeting deadlines and quality standards
• Analyze business requirements and propose appropriate technical solutions with a continuous improvement mindset.

Senior Fullstack Developer, .NET, C# – Angular

• Participate in the design and evolution of a strategic application dedicated to price optimization.
• Develop mobile applications in React Native (navigation, state management, native bridges).
• Design and develop fullstack applications with Java/Spring Boot (back-end focused) and Angular, applying Clean Architecture and SOLID principles.
• Architect microservices and event-driven solutions, with a strong focus on performance and maintainability.
• Manage databases (relational and document-oriented) and optimize queries for large-scale processing.
• Industrialize DevOps practices: CI/CD, test coverage (Sonar), and integration of craftsmanship best practices.
• Collaborate with business teams to analyze requirements and propose appropriate solutions while meeting deadlines and quality standards.
• Contribute to continuous improvement of processes and tools, adopting an agile approach (Scrum).

Senior Fullstack Developer, Java/Angular – Back-end Focus

• The Java Tech Lead (M/F) for our WMS product will be responsible for leading the major technological transformation of our team based in Troyes, as part of the development and evolution of our WMS solution.
• Successfully migrate the team's technology stack and ensure the secure construction of the new WMS product
• Ensure sustainable technical choices, aligned with the existing product and the group's strategy
• Raise the team's collective technical level and promote a culture of excellence
• Ensure the overall technical coherence of the product
• Deliver smooth, high-quality, and sustainable delivery
• Contribute to development by taking ownership of structurally important or highly complex technical topics

Tech Lead, Java

• Join our AI Lab as a Backend Product Engineer and help accelerate Qonto's transition to an AI-first product.
• Ship user-facing AI agents that transform how 600,000+ businesses manage their finances, working in small, autonomous squads under the guidance of Sophie, our Manager for the AI Lab.
• Deliver a new AI agent every 6 weeks, owning the full backend and AI logic from scoping to deployment — balancing speed with reliability and minimal technical debt.
• Architect pragmatic LLM guardrails and future-proof components that hold up in a regulated banking environment and don't need rewriting three months later.
• Use AI coding tools (Cursor, Claude Code, Copilot…) for ~70% of your coding to review, refine, and ship features faster.
• Contribute to frontend (React/JS) via vibe coding when needed, with the FE engineer reviewing your PRs — so the squad stays unblocked.

Backend Product Engineer – Python, AI

• Design custom technical architectures to integrate and deploy solutions smoothly and continuously
• Set up the development environment and development standards
• Propose and promote best practices to ensure the scalability and performance of the solution
• Work within client teams or on internal projects

Java Architect

• Design, build, and scale public-facing APIs in Go, hosted on GCP, serving millions of users with high availability and low latency.
• Ensure backend reliability through comprehensive testing strategies and safe, rollout processes for API releases.
• Monitor, troubleshoot, and optimize backend systems using Datadog, ensuring proactive reliability for player-facing services.
• Collaborate with game teams, data engineers, and product managers to align technical solutions with business goals.
• Contribute to and improve CI/CD pipelines — including GitHub Actions workflows with Terraform, and supporting Jenkins-based game pipelines alongside the dedicated owner.
• Support the development and maintenance of internal tools and services in TypeScript/Node.js, hosted on AWS.

Senior Back End Developer

• Participar en el diseño y desarrollo de soluciones backend, liderando técnicamente al equipo y trabajando en un entorno ágil e internacional.
• Colaborar con equipos multidisciplinares, tomar decisiones técnicas y contribuir a la mejora continua de la arquitectura, los patrones de diseño y los procesos de desarrollo.
• Crear y estructurar aplicaciones de software de alta calidad utilizando Java y tecnologías relacionadas.
• Participar en el desarrollo de las funcionalidades más complejas.
• Trabajar en estrecha colaboración con equipos multifuncionales, incluidos product managers, diseñadores y otros ingenieros, para ofrecer soluciones de software robustas.
• Realizar revisiones de código exhaustivas para garantizar la calidad, el rendimiento y la seguridad.
• Supervisar los desarrollos realizados por el equipo.
• Difundir buenas prácticas y procesos de desarrollo.
• Mantenerse actualizado/a con las últimas tendencias y tecnologías del sector para mejorar continuamente las prácticas de ingeniería de software.
• Proponer mejoras en el desarrollo de aplicaciones.
• Proporcionar orientación y mentoría a desarrolladores/as junior, asegurando las mejores prácticas en codificación y diseño.
• Ayudar al equipo a identificar el trabajo pendiente en un proyecto.

• Strengthen teams on project-based engagements
• Develop applications using Java and Spring Boot
• Collaborate with teams on assignments and projects

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