Junior Developer in Teknon

October 2014 – April 2015

I developed a medical system using the following technological stack:

  • Spring Boot Framework, Spring/Hibernate integration with MySQL and Spring MVC Restful Web Services API.
  • Android with Material Design UI for Lollipop and backwards compatibility.
  • OpenShift RedHat Cloud: Apache HTTP server+Apache Tomcat 7.
  • Complete end-to-end security system: AES, CBC, and PKCS5 encryption on local Android DB, HTTPS client/server communication, Spring Security hashing algorithm for remote MySQL DB.
  • Bidirectional synchronisation between local Android DB and remote MySQL DB via REST API. This feature allows the user to switch between different devices.
  • Development tools: IntelliJ IDEA, Maven Build System, FindBugs, GitHub & Bitbucket SCMs, Basecamp project management platform. Agile methodology with rigorous iterative development approach.

Patients, using their credentials to access, introduce urological measurements on the Android app. The app sends those measurements to the Spring Boot Web Service programmed using Rest Template API. The Backend uses Hibernate to manage all Java objects and saving the data into the database.


Warren de Leon worked for us part time developing a web based measurement system for some urologic symptoms and data.

We were very satisfied with his work, and also with his cooperative and frienldly attitude. Not only did he develop the application we needed, but he also helped us to solve some everyday problems that arouse in our office´s devices.

José Emilio Batista MD.