Alexandros Trifyllis

Personal Information

Date of birth 07/06/1980 a.trifyllis@gmail.com atrifyllis https://github.com/atrifyllis

Summary

I am a full-stack senior developer with more than 12 years of experience.
My areas of expertise and interest are backend development using Spring/ Spring Boot technologies (or Java EE) and frontend development using Typescript (or Javascript) with AngularJS/Angular 2+. I am interested in both the design/architecture phase of a project and the development phase. I am also interested in Devops, Continuous delivery and performance tuning. I consider myself a problem-solver and a solution-oriented developer. I like working in Agile teams and co-operating with my colleagues, sharing knowledge and expertise to provide the best possible result for the customers.

Job-related skills

Backend Frontend / Other

  • Languages: Java, Kotlin, Groovy (using DSLs and writing Spock tests), (some C and C# in the past)

  • Web Frameworks: Spring, Java EE 7

    • Spring Projects: Spring Boot, MVC, Data, JMS, Security, AOP, Hateoas, Cloud

    • Java EE JSRs: CDI, EJB, JPA, JMS, JAX-RS, JAX-WS (CXF), JSF

  • ORMs: Hibernate, EclipseLink

  • Databases: PostgreSQL, Oracle, MS SQL Server, MySQL, (some DB2 in the past)

  • Database migration: Flyway, Liquibase

  • Application Servers: Tomcat, Weblogic, Wildfly, (Websphere in the past)

  • Build Tools: Gradle, Maven

  • Testing: jUnit, Spock, Mockito, Arquillian, AssertJ, Hamcrest, jMeter, Testcontainers

  • Infrastructure: Docker, Kubernetes, Docker compose, Docker swarm

  • Languages: Typescript, Javascript

  • Frameworks: AngularJS/Angular 2+, (jQuery in the past), (some Vue.js)

  • State management: ngrx (Redux)

  • Testing: Jasmine, Jest, Karma, Selenium

  • Other: HTML, CSS/SCCS, Bootstrap, PrimeNG

Other Tools & Methodologies

  • Version control systems: Git, SVN

  • Collaboration tools: Jira, Confluence, BitBucket, Github, Gitlab

  • IDEs: IntelliJ, (Eclipse, Netbeans in the past)

  • Continuous Integration: Jenkins, Sonar, Artifactory/Nexus

  • Observability/Logging: SLF4J (logback or log4j), ELK stack, VisualVm, Grafana, Loki, Tempo, Prometheus

  • Methodologies: Agile methods, SCRUM

  • Business Modelling: UML, Activiti/Camunda BPM

Professional Experience

Senior Software Engineer at Atos, Remote

April 2022 to Now (On going)

I am part of the team mainly responsible for maintenance/defect resolution in the Entry Exit System of euLisa. I created a small tool to improve the experience of reproducing bugs, to be used by the team members (using Spring Batch). I am involved in non-functional bugs and issues as well. I have acquired expertise in the Workflow Engine subsystem, which is a Spring boot microservice that mainly uses Drools to implement the most complex business logic area of the system. I had to understand the business quite extensively to be able to implement new/missing features as well as to fix complex bugs. I am also heavily involved in some devops tasks e.g. coordinating releases, making sure that everything is running smoothly in development/testing environments.

Senior Software Engineer at Trasys Greece, Athens (Greece)

May 2020 to April 2022

I am working on the development of the UK Emissions Trading System. It is an enterprise application developed with Spring Boot/Angular, PostgreSQL, Keycloak as Identity and Access Management system, Apache Kafka for messaging. Among others, I was responsible for creating a custom migration mechanism in Keycloak to be able to manage its configuration in a versioned manner. Investigated complex issues concerning Kafka configuration for producers when multiple instances of an application are deployed. Finally, I was responsible for the whole design and development of the reporting microservice.

Senior Software Engineer at Viabill, Remote

January 2020 to April 2020

I was part of the core product team, initially worked on extracting a microservice from the main monolithic application. After that I worked on various new features and bugs concerning mainly the checkout module. Technologies used: Java/Spring Boot, MariaDB, Apache Camel, Domain Driven Design, Event Driven Architecture.

Senior Software Engineer at Trasys Greece, Athens (Greece)

January 2016 to November 2019

As a Software Engineer in Trasys I was part of several teams/projects for clients including European Organisations and the private sector. I was involved in design and development of web applications using Java/Spring/Java EE on the backend and Angular/Angular 2+ on the frontend.

Some of the projects I was involved in include:

  • Design and development of a REST API and also complete rewrite of the frontend part for a legacy web application for a European Agency. Technologies used were Spring Boot, Angular 7 (Bootstrap, ngrx), Oracle DB. I was mainly responsible for the frontend architecture, but also worked on backend features. I was also responsible for creating Jenkins pipelines using Groovy DSL.

  • Design and development of a modular web application used for administration tasks for a DG of the European Commission (Contacts management, User management, etc.). The technologies used were Spring Boot, Angular 4 (PrimeNG, Bootstrap, ngrx, eUI). Oracle DB. I was mainly responsible for the frontend architecture, but also worked on backend features.

  • Development of the Cloud Infrastructure project for a European Agency. This agency provides for its clients a private cloud space were they can manage instances of its applications. This cloud infrastructure consists of several microservices and the technologies used were Java EE, RxJava and Apache Kafka.

  • Development of existing web application of banking sector client used for managing sanction lists. Technologies used were Spring, AngularJS, Oracle DB.

  • Development of web application for a European Agency, used by the members state to submit Clinical Trials. I was responsible for developing several features in Java EE/AngularJS, for the backend validation solution/ infrastructure and for creating a 'Test Object' infrastructure. I also worked on some features in Activiti.

  • Support and development on the Reportnet platform of the European Environment Agency. My role was to coordinate with the rest of the dev team for the support and development activities. I was responsible for designing and implementing a PoC for an Angular 6 dynamic forms library, to be used potentially in several web applications. Technologies used were Spring/Spring Boot, XQuery, Angular 5, Vue.js, Rancher.

Software Engineer at Interbanking Systems S.A., Athens (Greece)

September 2010 to December 2015

As a Software Engineer in Interbanking Systems, I worked in several in-house and external projects as both Software engineer and technical lead designing and implementing mainly web applications in Java/Spring on the backend and jQuery on the frontend.

Some of the projects I was involved in include:

  • Development and integration with a new Eurozone e-payment system. Interbanking Systems was responsible for implementing a solution that will be used by the Greek Banks to connect to the central e-payment system "hub". The solution is implemented using Java EE 7 (deployed in Wildfly), Web Services using JAX-WS (CXF) and the challenging requirement was the integration with advanced security mechanisms (WS-Security, WS-SecurityPolicy, WS-Addressing etc.). The database used is MS SQL Server.

  • Technical management and development of web application (e-Payments) for the General Secretariat for Information Systems (Spring Web Application). Solved critical issues with Weblogic integration. Implemented Taxisnet integration, web services and adapter for connecting to Interbanking Services Online Payment System.

  • Developed internal backend services using C.

  • Responsible for setting up the continuous delivery infrastructure for the companies application Sector (Jenkins/ Artifactory/Sonar).

Software Engineer at Byte S.A., Athens (Greece)

October 2007 to June 2010

As a Software engineer in Byte, I worked in several projects for our clients mostly doing full-stack development using Java/J2EE* in backend and jQuery/Javascript in frontend.

Some of the projects I was involved in include:

  • Design, development and support of web application "Life Quotation" for a large insurance company. The application’s purpose is the creation of insurance offers about Life, Health and Pension. Development in J2EE (single-page application), communication with Web Services of the insurance company. Other technologies: Servlets, JSP, jQuery, JiBX, Websphere.

  • Design, development and support of web application about the monitoring of a warehouse’s production process (packaging – transporting of mobile phone products). Development in Java EE (Ajax enabled application). MS SQL backend. Other technologies: Servlets, JSP, Javascript, Tomcat.

Software Engineer at Lambrakis press S. A., Athens (Greece)

January 2005 to July 2005

Developed the Customer Management Application for the Archive Department. Technology used was C#.

Education and Training

Academic Background

Oxford university, United Kingdom

10/2005 - 10/2006
Title: Master of Science in Computer Science
Level: Master Degree

School of Engineering, University of Patras, Greece

09/1998 - 09/2004
Title: Diploma in Computer Engineering and Informatics
Level: Bachelor + Master (5-years studies)

European School of Brussels, Belgium

01/1988 - 07/1998
Title: European Baccalaureate Certificate
Level: Secondary school

Certifications/Training

Title Date Type Institute

Machine Learning

29/10/2018

Certification

Stanford University, Coursera

Oracle Java SE 8 Programmer I

02/06/2017

Certification

Oracle

Certified Kubernetes Application Developer (CKAD)

21/12/2022

Certification

Linux Foundation

Languages

UNDERSTANDING SPEAKING WRITING

Listening

Reading

Spoken interaction

Spoken production

Greek

Native

English

C1

C1

C1

C1

C1

French

C1

C1

C1

C1

C1

German

A1

A1

A1

A1

A1
Levels: A1/A2: Basic user - B1/B2: Independent user - C1/C2: Proficient user Common European Framework of Reference for Languages