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Hi, I am Attila

Attila Fejér

Software Engineer and Technical Coach

I’m hard to fit in a single box since I consider myself many things. Software engineer. Tech trainer, mentor, coach, and author. Dog and cat dad. Amateur dog handler. Guitar hobbyist. Weekend hiker. Easy rider.

And many more. Because life without passion and variety is wasted.



Lead Developer, Architect, Software Craftsmanship Coach, Developer Advocate
IBM ISSC Hungary Kft.

Feb 2020 - Present, Budapest, Hungary

  • Designed and implemented highly scalable software products in a cloud environment
  • Mentored, trained, and coached people and teams applying software development best practices and adopting new internal tooling
  • Training programs impacted 10.000+ developers
  • Collected mentee and leadership feedback and periodical DORA assessments


Apr 2018 - Present, Remote

  • Researched and wrote technical articles for online publications
  • Wrote almost 30 posts
  • Rated by editorial feedback and consumer comments

Independent Consultant and Technical Coach

2014 - 2020, Budapest, Hungary

  • Helped clients to build, test, and deploy scalable, highly available, and modular software products, maintain legacy applications, and upskill their developers as an embedded coach
  • Formed the mindset of 15.000+ developers
  • Improved DORA metrics

Lead Software Developer
Apertus Nonprofit Kft.

Jul 2017 - Jul 2019, Budapest, Hungary

  • Collaborated on all stages of systems development lifecycle, from requirements gathering to production releases
  • The applications made 150.000+ users’ job easier
  • Performance tests results improved, client satisfaction increased, reported issues decreased

Budapest University of Technology and Economics

Sep 2010 - Jan 2018, Budapest, Hungary

  • Delivered presentations in computer science, information theory, and digital design, led laboratory courses
  • Directly helped the progression of 500+ university students
  • Got consistently high scores from students’ satisfaction measurements

Software Development Trainer
EPAM Academy, Pentaschool, Ruander, Masterfields, Számalk

Jun 2013 - May 2017, Budapest, Hungary

  • Developed software developer course plans and delivered classes about technology
  • Made 300+ people progress in their software developer journey
  • Got consistently high scores from students’ satisfaction measurements

Co-Founder, CEO, Software Engineer
Just Another Company Kft.

Apr 2012 - Jun 2015, Budapest, Hungary

  • Led the company in executive and technological aspects
  • Shipped solutions for 20+ partners
  • Increased company income, profit, client base, and NPS scores


Replacing Type Code With Class
RockIT 23 Apr 2023

In the previous part, we had an overview of why switch-case could be hard to maintain. This part will focus on the simplest scenario: when type-code only affects data, not behavior. We’ll do this by modeling a pizzeria.

The Dark Side of Switch-Case
RockIT 23 Apr 2023

In a nutshell: switch-case makes code harder to maintain. We’ll understand the reasons to eliminate it and see when its usage is justified.

Tech Content Creators' Responsibilities
RockIT 15 Mar 2023

As online learning flourishes, it’s easier than ever to learn new things. If we search for virtually any technology, we’ll get remarkable amounts of results. In some sense, it’s good, since we have the freedom to choose. But how should we make that choice?

Code Smells
Baeldung CS 27 Jun 2021

Explore ideas how to prevent a codebase’s quality from decreasing.

Baeldung CS 10 May 2021

Learn that refactoring is a natural and essential part of a software’s evolution

What Does It Mean to Program to Interfaces?
Baeldung CS 7 Mar 2021

A quick and practical introduction to programming to an interface.

Object-Oriented vs Functional Programming
Baeldung CS 8 Dec 2020

Learn about object-oriented and functional programming and discover that they are not mutually exclusive.

The General Concept of Polymorphism
Baeldung CS 12 Nov 2020

Learn what polymorphism is with examples.

Difference Between when() and doXxx() Methods in Mockito
Baeldung 8 Sep 2020

Learn the advantages and disadvantages of the configuring a mock object the when().thenXxx() or the doXxx().when() way.

Object-Orientation in the Real World
Baeldung CS 9 Aug 2020

Explore the core concepts behind the object-oriented programming.

Mapping a Single Entity to Multiple Tables in JPA
Baeldung 27 Oct 2019

Learn how to map a single Java entity to multiple database tables using JPA.

Command-Line Arguments in Java
Baeldung 6 Sep 2019

Explore how to configure your Java applications using command-line arguments.

Composition, Aggregation, and Association in Java
Baeldung 3 Aug 2019

Explore the properties and representation of composition, aggregation, and association in Java.

An Introduction to Epsilon GC: A No-Op Experimental Garbage Collector
Baeldung 7 Mar 2019

Learn how Epsilon works, and explore the common use cases.

An Introduction to ZGC: A Scalable and Experimental Low-Latency JVM Garbage Collector
Baeldung 9 Feb 2019

Explore how Z Garbage Collector manages to keep low pause times on even multi-terabyte heaps.

Java 8 Streams peek() API
Baeldung 16 Jan 2019

Learn about the peek() method and explore the lifecycle of a stream.

Mapping a Dynamic JSON Object with Jackson
Baeldung 26 Dec 2018

Explore multiple ways of handling dynamic JSON objects with Jackson.

Remove Leading and Trailing Characters from a String
Baeldung 3 Dec 2018

Explore several ways to remove leading and trailing characters from a String.

Many-To-Many Relationship in JPA
Baeldung 15 Nov 2018

Learn how to model a many-to-many relationship in Java using JPA

Heap Sort in Java
Baeldung 18 Oct 2018

Learn how to implement a Binary Heap and Heap Sort in Java.

Use Criteria Queries in a Spring Data Application
Baeldung 30 Aug 2018

A quick tutorial to using JPA Criteria Queries using Spring Data JPA.

Remove All Occurrences of a Specific Value from a List
Baeldung 7 Aug 2018

In this tutorial, we’ll see multiple solutions to efficiently removing all occurrences of a value, describing the pros and cons.

Using Spring ResponseEntity to Manipulate the HTTP Response
Baeldung 3 Jul 2018

Learn how to manipulate the HTTP response using the ResponseEntity class.

Using Spring @ResponseStatus to Set HTTP Status Code
Baeldung 3 Jul 2018

Have a look at the @ResponseStatus annotation and how to use it to set the response status code.

Spring Core Annotations
Baeldung 7 Jun 2018

Explore the most commonly used Spring core annotations.

Spring Scheduling Annotations
Baeldung 2 Jun 2018

Explore the most common Spring scheduling annotations.

Spring Web Annotations
Baeldung 1 Jun 2018

Explore the main annotations you can use to handle HTTP requests and responses in Spring MVC.

Spring Boot Annotations
Baeldung 1 Jun 2018

Explore the Spring Boot Annotations.

Spring Data Annotations
Baeldung 31 May 2018

Learn about the most important annotations we need to handle persistence using the Spring Data project

Working with Boolean in Thymeleaf
Baeldung 25 Apr 2018

Take a look at how to work with boolean values in Thymeleaf.


M.Sc. in Electrical Engineering
B.Sc. in Computer Engineering
High School
High School

Honors & awards

XPFarm Red Belt - Software Craftsmanship Coach
IBM Mar 2023

This award demonstrates a commitment to software craftsmanship, continuous learning, teamwork, the discipline to stick to daily practice, and the passion for knowledge sharing.

Outstanding Technical Achievement Award
IBM Apr 2022

Special recognition for the top recipients for developing technical achievements.

Fivefold IBM CIO Hungary Champion
IBM 2021-2022

This award represents the dedication and passion one has put into making CIO Hungary a better place.

OITM Competition 2018 - Java (Spring, Hibernate) Category 1st Prize

Hungarian National IT Challenge (Országos IT Megmérettetés)

OITM Competition 2018 - Java EE Category 1st Prize

Hungarian National IT Challenge (Országos IT Megmérettetés)

OITM Competition 2018 - Java Innovation Category 2nd Prize

Hungarian National IT Challenge (Országos IT Megmérettetés)

OITM Competition 2018 - Overall 2nd Prize

Hungarian National IT Challenge (Országos IT Megmérettetés)

Scientific Students' Associations (TDK) 2nd Prize

Integrated Development Environment for a Custom Soft-Core Processor

Scientific Students' Associations (TDK) 2nd Prize

Push Notifications for Sensor Networks with Internet Connection

WTW (Win The Web) 24h Programming Competition 1st Place
Jan 2011