Available to hire
Hi, I’m Hamdi Rajab, a results-driven full-stack engineer with over 9 years of experience delivering scalable enterprise applications. I specialize in Java, Spring Boot, and Angular, with hands-on AI integration that enhances translation, profiling, automation, and user support across platforms. I’ve led the development of cloud-native recruitment and education solutions used by 1,500+ users across multiple countries, delivering real-time capabilities and robust architectures.
Outside of coding, I’m passionate about emerging technologies and solving complex business challenges. I’m known for my strong sense of responsibility, dynamic mindset, and excellent communication and collaboration skills, which help me drive teams toward robust, user-focused outcomes.
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Language
English
Fluent
German
Intermediate
French
Fluent
Arabic
Fluent
Work Experience
Lead Full-Stack Developer & Solution Architect at Karray-Pflege GmbH, Germany
July 31, 2025 - August 26, 2025Led the architecture and development of a cloud-native recruitment platform for healthcare professionals, serving 1,500+ users internationally. Developed features for candidate management, real-time tracking, and employer engagement using Spring Boot and Angular within a microservices architecture. Integrated AI technologies such as OpenAI GPT to provide multilingual translation, profile summarization (reducing screening time by 40%), and an AI FAQ chatbot (reducing support requests by 60%). Implemented AWS API Gateway and CI/CD pipelines using Docker and GitHub Actions to ensure secure, scalable, and zero-downtime releases.
Full Stack Developer at Private Contractor, Germany
June 30, 2022 - August 26, 2025Developed an educational platform enabling teachers to create interactive curriculum-based games and track student performance with real-time analytics. Built Java Spring Boot REST APIs and reusable Angular components using Canvas, improving UI reliability through unit testing (Karma, Jasmine). Collaborated in an Agile Scrum environment supporting sprint delivery and CI/CD pipelines for automated releases.
Backend Developer at Machinestalk, Tunisia
June 30, 2021 - August 26, 2025Designed and developed scalable microservices for a Smart Municipal Service Management system enabling digital management of municipal services. Integrated external platforms, including OpenMaint, ThingsTalk, and Keycloak for secure role-based access. Developed robust RESTful APIs and SOAP integrations with thorough testing, improving automation, data consistency, and interoperability.
Backend Developer at Machinestalk, Tunisia
March 31, 2020 - August 26, 2025Implemented real-time data synchronization between a mobile app and IoT platforms via Apache Kafka for live telemetry data tracking (fuel, speed, location). Developed RESTful APIs and configured Kafka brokers with custom producers and consumers. Integrated Keycloak for centralized authentication and authorization to enhance security.
Full Stack Developer Java & AngularJS at Machinestalk, Tunisia
August 31, 2019 - August 26, 2025Contributed to ThingsTalk, an enterprise IoT platform for real-time device and asset monitoring. Optimized legacy code and developed backend services in Spring Boot and frontend modules in AngularJS. Built centralized notification systems and enhanced platform flexibility and interoperability by integrating third-party APIs within an Agile Scrum team.
Full Stack Developer - Scrum Master at Machinestalk, Tunisia
April 30, 2018 - August 26, 2025Served as Scrum Master for a team of 6 developers in building an MVP car-sharing management system using Java and Angular. Led sprint planning, team coordination, and agile delivery.
Java Developer - BPM Engineer at Machinestalk, Tunisia
November 30, 2017 - August 26, 2025Designed business processes and developed HR and Finance automation modules using Alfresco, Camunda, and Java to streamline workflows and reduce manual effort. Supported department-wide administrative process improvements.
Lead Full-Stack Developer & Solution Architect at Karray-Pflege GmbH, Germany
July 31, 2025 - August 26, 2025Led the development and architecture of a cloud-native international recruitment platform supporting healthcare professional lifecycle management. Managed real-time candidate tracking for 1,500+ users across multiple countries. Integrated AI features using OpenAI GPT for multilingual translation, profile summarization reducing screening time by 40%, and an FAQ chatbot decreasing support requests by 60%. Implemented AWS API Gateway for secure, scalable API management with CI/CD pipelines for zero-downtime releases.
Full Stack Developer at Private Contractor, Germany
June 30, 2022 - August 26, 2025Developed an educational platform enabling teachers to create games and track student performance with real-time analytics. Built Java Spring Boot REST APIs and reusable Angular components with unit tests to ensure reliability and accelerates feature delivery. Collaborated in Agile Scrum environment supporting sprint-based delivery and CI/CD pipelines for automated releases.
Backend Developer at Machinestalk, Tunisia
June 30, 2021 - August 26, 2025Developed digital solutions enabling contractors to manage municipal services using microservices architecture. Created scalable RESTful APIs integrating with external systems (OpenMaint, ThingsTalk, FMS, Digital ID) improving automation and interoperability. Implemented secure role-based access with Keycloak and tested protocols with Mockito to reduce production bugs.
Backend Developer at Machinestalk, Tunisia
March 31, 2020 - August 26, 2025Implemented real-time data synchronization between mobile app and IoT platform using Apache Kafka. Enhanced live tracking and telemetry data reliability with Kafka monitoring tools. Developed RESTful APIs with Spring Boot and integrated Keycloak for centralized authentication and authorization.
Full Stack Developer Java & AngularJS at Machinestalk, Tunisia
August 31, 2019 - August 26, 2025Contributed to the ThingsTalk enterprise IoT platform by optimizing legacy code and developing a centralized notification module. Built backend RESTful services and dynamic AngularJS dashboards, integrating third-party APIs to expand system functionality within Agile Scrum teams.
Full Stack Developer - Scrum Master at Machinestalk, Tunisia
April 30, 2018 - August 26, 2025Served as Scrum Master for a team of 6 developers to deliver an MVP for a Java and Angular car-sharing management app, facilitating agile project management and sprint execution.
Java Developer - BPM Engineer at Machinestalk, Tunisia
November 30, 2017 - August 26, 2025Contributed to designing business processes and developing HR and Finance automation modules using Alfresco, Camunda, and Java. Streamlined workflows and reduced manual effort across multiple departments.
Lead Full-Stack Developer & Solution Architect at Karray-Pflege GmbH (PFS Matching App)
July 1, 2025 - September 23, 2025Led architecture and development of a cloud-native recruitment platform for healthcare professionals, including candidate management, email notifications, and meeting scheduling. Served 1,500+ users across multiple countries with real-time candidate tracking and partner-institution monitoring. Enabled candidates to upload documents and select employers within their accounts. Built a microservices-based Spring Boot backend and an Angular frontend. Integrated AI (OpenAI GPT) for multilingual translation, profile summarization (reducing screening time by ~40%), and an FAQ chatbot reducing support requests by ~60%. Implemented AWS API Gateway for secure API management and established CI/CD pipelines using Docker and GitHub Actions to enable zero-downtime releases and faster development cycles.
Full stack Developer at Private Contractor, Interactive Learning Platform
June 1, 2022 - September 23, 2025Developed a curriculum-based educational platform enabling teachers to create games and track student performance with real-time analytics. Designed interactive game mechanics (Canvas-based) to enhance engagement. Built REST APIs with Java Spring Boot and reusable Angular components; implemented unit tests (Karma, Jasmine) to ensure UI reliability. Worked in an Agile Scrum environment and supported CI/CD pipelines for automated releases.
Backend Developer at Machinestalk
June 1, 2021 - September 23, 2025Enabled contractors to digitally manage municipal services (bin allocation, user registration, inspections) using a microservices architecture with OpenMaint for infrastructure tracking and Keycloak for secure, role-based access. Designed scalable integration architectures and developed robust RESTful APIs with Spring Boot to connect with external platforms (OpenMaint, ThingsTalk, FMS, Digital ID), improving automation, data consistency, and interoperability across enterprise and third-party systems. Implemented REST and SOAP protocols with integration tests using Mockito, reducing production bugs.
Backend Developer at Machinestalk
March 1, 2020 - September 23, 2025Implemented real-time data synchronization between a mobile app and the ThingsTalk IoT platform using Apache Kafka. Enabled live tracking of users, assets, and vehicles via mobile telemetry (fuel, speed, location) and improved reliability with Kafka monitoring (KaDeck) for message integrity. Implemented RESTful APIs with Spring Boot for CRUD operations and configured Apache Kafka brokers with custom producers & consumers. Integrated Keycloak for centralized authentication & authorization, enhancing security and simplifying user access management.
Full Stack Developer Java & AngularJs at Machinestalk
August 1, 2019 - September 23, 2025Contributed to ThingsTalk (Aramco’s customized version of ThingsBoard), an enterprise IoT platform for real-time monitoring of buildings, devices, and vehicles. Optimized and extended a legacy codebase while building a centralized notification module and customizing user, device, asset, and role management, improving maintainability and platform reliability. Developed RESTful backend services with Spring Boot, dynamic dashboards with AngularJS, and integrated third-party APIs to expand system functionality and external interoperability.
Full Stack Developer - Scrum Master at Machinestalk
April 1, 2018 - September 23, 2025Served as Scrum Master for a cross-functional team of 6 developers, leading the development of an MVP for a Java and Angular car-sharing management system.
Java Developer - BPM Engineer at Machinestalk
November 1, 2017 - September 23, 2025Contributed to the design of business processes and developed HR and Finance automation modules using Alfresco, Camunda and Java, streamlining administrative workflows and reducing manual effort across departments.
Lead Full-Stack Developer & Solution Architect at Karray Pflege GmbH
July 1, 2025 - July 1, 2025Led the architecture and development of a cloud-native recruitment platform (PFS-Matching-App) supporting candidate management, email notifications, and meeting scheduling; managed healthcare professionals’ lifecycle from application to visa issuance; served 1,500+ users across countries with real-time candidate tracking and partner institution monitoring; enabled candidates to upload documents and select employers directly via their account; integrated AI (OpenAI GPT) for multilingual translation, profile summarization (reducing screening time by ~40%), and an FAQ chatbot (reducing support requests by ~60%); implemented AWS API Gateway for secure, scalable API management and established CI/CD pipelines (Docker, GitHub Actions) for zero-downtime releases.
Full Stack Developer at Interactive Learning Platform
June 1, 2022 - June 1, 2022Developed a curriculum-based educational platform enabling teachers to create games and track student performance with real-time analytics; facilitated communication between students and teachers; designed interactive game mechanics with real-time responsiveness; built Java (Spring Boot) REST APIs and reusable Angular components (Canvas), with unit tests (Karma, Jasmine) to accelerate feature delivery and improve UI reliability; collaborated in an Agile Scrum environment and supported CI/CD pipelines for automated releases.
Backend Developer at Machinestalk
June 1, 2021 - June 1, 2021Enabled contractors to digitally manage municipal services (bin allocation, user registration, inspections) using a microservices architecture with OpenMaint for infrastructure tracking and Keycloak for secure, role-based access; designed scalable integration architectures and developed robust RESTful APIs with Spring Boot; connected with external platforms (OpenMaint, ThingsTalk, FMS, Digital ID) to improve automation, data consistency, and interoperability; implemented REST and SOAP protocols with integration tests using Mockito to reduce production bugs.
Backend Developer at Machinestalk
March 1, 2020 - March 1, 2020Implemented real-time data synchronization between a mobile app and the ThingsTalk IoT platform using Apache Kafka; enabled live tracking of users, assets, and vehicles via mobile telemetry; improved reliability with Kafka monitoring (KaDeck); implemented RESTful APIs with Spring Boot for full CRUD operations and configured Kafka brokers with custom producers & consumers; integrated Keycloak for centralized authentication & authorization.
Full Stack Developer Java & AngularJs at Machinestalk
August 1, 2019 - August 1, 2019Contributed to ThingsTalk (Aramco’s customized version of ThingsBoard), an enterprise IoT platform for real-time monitoring of buildings, devices, and vehicles; optimized and extended a legacy codebase while building a centralized notification module and customizing user, device, asset, and role management; developed RESTful backend services with Spring Boot, dynamic dashboards with AngularJS, and integrated third-party APIs within an Agile Scrum team.
Full Stack Developer - Scrum Master at Machinestalk
April 1, 2018 - April 1, 2018Led as Scrum Master for a cross-functional team of 6 developers, guiding the MVP development for a Java and Angular car-sharing management system.
Java Developer - BPM Engineer at Machinestalk
November 1, 2017 - November 1, 2017Contributed to the design of business processes and developed HR and Finance automation modules using Alfresco, Camunda and Java, streamlining administrative workflows and reducing manual effort across departments.
Education
Master of Science in Computer Science at National School of Engineers of Sousse (ENISo), Tunisia
January 1, 2013 - June 30, 2016Preparatory Cycle at Preparatory Institute for Engineering Studies, Sfax, Tunisia
January 1, 2009 - December 31, 2012Master of Science in Computer Science at National School of Engineers of Sousse (ENISo), Tunisia
January 1, 2013 - June 30, 2016Preparatory Cycle at Preparatory Institute for Engineering Studies, Sfax Tunisia
January 1, 2009 - December 31, 2012Master of Science in Computer Science (Minor: Software Engineering) at National Engineering School of Sousse (ENISo), Tunisia
January 1, 2013 - January 1, 2016Preparatory Cycle at Preparatory Institute for Engineering Studies, Sfax Tunisia
January 1, 2009 - January 1, 2012Master of Science in Computer Science (Minor: Software Engineering) at National Engineering School of Sousse (ENISo), Tunisia
January 1, 2013 - January 1, 2016Preparatory Cycle at Preparatory Institute for Engineering Studies, Sfax, Tunisia
January 1, 2009 - January 1, 2012Graduation Project: Non-Conformity Management System at WEVIOO, Tunis, Tunisia
February 1, 2016 - June 1, 2016Qualifications
Industry Experience
Healthcare, Education, Software & Internet, Transportation & Logistics, Government, Professional Services, Manufacturing
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
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