Senior Fullstack Engineer (Python + React.js)

Senior Fullstack Engineer We are looking for a highly skilled Fullstack Engineer to design, develop, and maintain scalable, secure, and efficient server-side applications. The ideal candidate should have experience in microservices architecture, API development, database management, and frontend ensuring high availability and performance of backend and frontend services. In this role, you will collaborate closely with frontend engineers, product managers, and other stakeholders to build robust backend solutions that power our applications. A strong focus on Separation of Concerns (SoC), security best practices, and performance optimization is crucial for success in this position. The Impact You’ll Make: Integrate models into backend systems and create API endpoints for model interaction (e.g., retrieving predictions). Develop and maintain scalable services, e.g. Microservices utilising REST, gRPC, or GraphQL, ensuring optimal performance and seamless integration. Optimize database queries and schemas to improve performance, scalability, and reliability. Implement security features, including authentication and authorization using industry-standard practices. Develop and maintain web interfaces using ReactJS Implement and maintain state management using tools such as Redux or React Query Collaborate with frontend developers to ensure efficient API integration and a seamless user experience. Troubleshoot and resolve production issues, ensuring high availability and minimal downtime. Write unit and integration tests to maintain code reliability and ensure high- quality releases. Continuously monitor and optimize backend performance using observability tools such as Datadog, Cloud Watch or similar. Participate in design discussions and decision-making to enhance system robustness and scalability. Maintain technical documentation to ensure clear communication of system capabilities and updates. What You’ll Bring: Bachelor degree in Computer Science, Software Engineering, or any related field is required, or equivalent practical experience. Minimum 8 years of experience in backend development, with a strong focus on building scalable, high-performance systems. Technical Skills: Python expertise, with hands-on experience building backend services and APIs using FastAPI, Flask or similar. Experience in designing and developing end-to-end (E2E) tests to ensure smooth integration between backend and frontend components. A solid understanding of microservices architecture, event-driven systems, and service-oriented design patterns. In-depth knowledge of SQL databases (e.g., PostgreSQL, MySQL) and NoSQL databases (e.g., MongoDB) for data management and optimization. Experience with ETLs and data transformation Solid expertise in HTML, CSS, JavaScript, and ReactJS. Extensive experience with cloud platforms such as AWS including services for database hosting, API management, and serverless computing. Proficiency with Docker for containerization and orchestration tooling such as ECS (Amazon Container Services), enabling scalable application deployment. Hands-on experience with API security protocols, including JWT, OAuth2, and OpenID Connect, Active Directory (now Microsoft Entra ID) to secure sensitive data and control access. Proficiency with Git for version control, GitHub Actions and CI/CD pipelines to automate and streamline development workflows. Proficiency with performance tuning and scalability techniques, such as load balancing, caching, and database indexing. Soft Skills: Strong analytical and problem-solving skills, with the ability to quickly assess and address technical challenges. Excellent communication skills, both written and verbal, for collaborating with cross-functional teams and documenting technical solutions. A proactive, self-motivated approach to addressing issues and driving improvements in backend systems. A strong commitment to continuous learning and staying up-to-date with emerging technologies and industry best practices. Nice-to-Have Qualifications: Familiarity with message brokers such as Kafka, or AWS SQS for handling asynchronous communication. Experience with Infrastructure as Code (IaC) tools like Terraform or CloudFormation for managing cloud infrastructure. Knowledge of observability and monitoring tools, such as Cloud Watch or Datadog, to track and troubleshoot system performance. Familiarity with serverless architectures (e.g., AWS Lambda) and event- driven programming paradigms. Exposure to Agile/Scrum methodologies and tools like Jira for managing tasks and sprint planning. Certifications in cloud technologies, such as AWS Certified Developer. Manage, host, and serve AI/ML models (MLOps), by ensuring their scalability, reliability, and performance in production environments. Location: Spain: flexible remote work, with availability to travel to the UK office in Hayes, West London, once per month. Some of the benefits you’ll enjoy working with us: The chance to join an organization with triple-digit growth that is changing the paradigm on how software products are built. The opportunity to form part of an amazing, multicultural community of tech experts. A highly competitive compensation package. Medical insurance. Come and join our #ParserCommunity. Follow us on