I'm a full-stack software engineer & architect with 10+ years' experience, ex-CTO in startups & enterprise software
Aktualisiert am 03.12.2024
Profil
Freiberufler / Selbstständiger
Remote-Arbeit
Verfügbar ab: 03.12.2024
Verfügbar zu: 100%
davon vor Ort: 50%
Node.js
React
Java
Softwarearchitektur
Software-Design
TypeScript
Fullstack
Back-End
Front-End
Spring
REST
GraphQL
German
fluent in written and spoken
English
fluent in written and spoken
Serbian
Muttersprache

Einsatzorte

Einsatzorte

Berlin (+150km)
Deutschland, Schweiz
möglich

Projekte

Projekte

3 years 9 months
2021-04 - now

Building and scaling an industry-specific, multi-sided platform business

CTO and Co-founder GraphQL Node.js PostgreSQL ...
CTO and Co-founder
  • Co-founded Berlin-based headless, API-first, backend-as-a-service (BaaS) platform designed for developers to build and scale industry-specific, multi-sided platform business
  • Led technical strategy, event-driven architecture, system design, software, and runtime architecture hands-on
  • Built and managed a high-performing tech team, contributing hands-on to backend services, frontends, infrastructure automation (infrastructure-as-code), and CI/CD pipelines.
  • Active in technical pre-sales, solution engineering, customer implementation projects, supporting and training partners and customers? developers
  • Actively participated in business development, securing investors, speaking and representing the company at industry conferences
GraphQL Node.js PostgreSQL Redis React Material-UI AWS (Elastic Beanstalk; Fargate; Lambda; CloudFront; etc.) Docker Stripe integrations multi-tenancy event-driven architecture headless API-first
on request
9 years 4 months
2015-09 - now

Personal projects

  • Authored a blog about work, studies, and life in Germany, catering to an audience with origins in former Yugoslavia, attracting over 30,000 monthly readers
  • Organized professional meetups in Berlin, Munich, and Hamburg for IT professionals and entrepreneurs from former Yugoslavia and informal meetups for blog readers, fostering community engagement and networking
  • Hosted guest authors, sharing diverse experiences and perspectives on life in Germany, enriching the blog?s content and audience reach
  • Acted as a contact person for Serbian media, providing insights on Germany for interviews with various business magazines and mass-media outlets, including BBC Serbia and Blic
2 years
2019-04 - 2021-03

Decomposing a monolithic e-com application

Backend Software Engineer SAP Hybris Spring Boot Hibernate ...
Backend Software Engineer
  • Member of the eCommerce team tasked with decomposing a monolithic eCom application into microservices and extending the eCom system to enable SAP?s platform business
  • Implemented multiple microsevices deployed on a Kubernetes cluster managed by Kyma
  • Provided technical leadership to an outsourced team and coordinated integrations, ensuring smooth collaboration across multiple teams, functions, and cultures
  • Mentored junior developers
  • Designed private REST APIs, wrote Lambdas, tests, and contributed to frontend development and testing
SAP Hybris Spring Boot Hibernate MariaDB REST & OpenAPI (Swagger) Flowable (workflow engine) Gherkin & Cucumber Gherkin & Cypress Microservices Continuous Integration
SAP Berlin
2 years 8 months
2018-08 - 2021-03

B2C classifieds platform

Co-Founder & CTO Java Spring Boot MongoDB ...
Co-Founder & CTO
  • Co-founded a B2C subscription-based classifieds platform that connects compatriots and highlights their services and events. Built the tech, product, and business teams, then focused on leading the tech and product development.
  • Led the hands-on design of the entire system, including software and runtime architecture. Architected and implemented multiple front-end and back-end services
  • Mentored junior developers and led the entire development lifecycle and product delivery
  • Learned valuable lessons from hiring mistakes, a non-lean approach & over-engineering
Java Spring Boot MongoDB JUnit & Mockito Cucumber REST APIs Docker AWS (Fargate; S3; CloudFront; CodePipeline) React Material-UI Stripe API
on request
1 year 3 months
2018-01 - 2019-03

Building virtual banks within companies

Consultant for SAP Finance SAP In-House Cash (internal virtual bank) Payments and Electronic Bank Statements SAP Bank Communication Management ...
Consultant for SAP Finance
  • Member of the SAP finance consulting team, specialized in setting up virtual banks within corporations (in-house cash management), cash pooling, liquidity management, payment processing, and bank integrations.
  • Implemented SAP In-House Cash solutions, acting as a virtual internal bank to streamline internal cash management and optimize payment processing
  • Implemented PoC with SAP Cash Application (ML-based invoice matching automation)
  • Connected treasury management systems to banks, enhancing the efficiency of payment and electronic bank statement processing
  • Conducted workshops and training sessions on SAP In-House Cash, Bank Communication Management, and SAP Cash Application, leveraging machine learning for finance
SAP In-House Cash (internal virtual bank) Payments and Electronic Bank Statements SAP Bank Communication Management SAP Cash Application (Machine Learning in Finance)
SAP Berlin
11 months
2016-12 - 2017-10

Recommendation system for the SAP community platform

Machine Learning Applied Researcher Python Java JavaScript ...
Machine Learning Applied Researcher
  • Member of the SAP AI lab, developing proof-of-concepts for a recommender system for the SAP-Community platform using knowledge graphs and various machine learning models
  • Conducted compression of different models, including graph-based, content-based, and collaborative filtering approaches, designing and developing a hybrid recommender system
  • One of the PoCs demonstrated the practical application and transitioned into production
  • Authored and defended a master thesis titled ?A Hybrid Recommender System for Documents based on Enterprise Knowledge Graphs,? based on this work
Python Java JavaScript Jupyter Notebook Docker Neo4j Machine Learning Knowledge Graphs Recommender Systems Word2Vec Doc2Vec Node2Vec PathSim FastText TF-IDF Embeddings dimensionality reduction matrix factorization semantic analysis ranking dithering graph-theory PageRank ItemRank SimRank
SAP Berlin
5 months
2015-10 - 2016-02

S/4 HANA ERP system

Frontend Developer (working student) JavaScript SAPUI5 SDK OData Services ...
Frontend Developer (working student)
  • Collaborated with the SAP Solution Manager team to develop an MVP version of their existing SAP ECC product, tailored for the S/4 HANA ERP system, utilizing OData REST APIs for seamless integration
  • Successfully built the MVP for the ?Test Management Dashboard for S/4 HANA?s automated testing,? which was later expanded into the fully-fledged ?Test Suite Dashboard? product
JavaScript SAPUI5 SDK OData Services REST APIs SAP Fiori
SAP Berlin
5 months
2014-11 - 2015-03

Bachelor?s thesis

Full Stack Developer SAP Hybris Java Android ...
Full Stack Developer
  • Worked in the SAP fintech lab team, developing PoC integrations in eCom & mCom space
  • Built integrations to different payment methods (e.g. stored-value accounts, SMS & wallet payments) on wearables (Pebble Watch, Google Glass) and SAP Hybris-based online shops
  • Contributed to four patent applications, with one patent successfully approved
  • Authored a bachelor?s thesis titled ?Integration of an Omni-Channel Commerce Platform with a Mobile Payment Solution? based on this work
SAP Hybris Java Android JS REST & SOAP APIs Ant PostgreSQL PhoneGap
SAP Walldorf
8 months
2014-02 - 2014-09

Software solutions for different departments

Software Engineer and Team Lead C# .NET IIS Webserver ...
Software Engineer and Team Lead
  • Developed custom software solutions for various Audi departments, focusing on desktop Windows applications and web applications
  • Advocated for and successfully introduced web application development, Kanban and SCRUM to enhance development processes
  • Initially hired as a software engineer and quickly promoted to tech lead, overseeing three projects and managing a team of up to five developers
  • Led the team in the design and implementation of both web and desktop applications
C# .NET IIS Webserver SQL Server JavaScript HTML5 CSS Highcharts Team Foundation Server Entity Framework DevExpress WinForms Web Apps Desktop Apps
Wisio Ingolstadt
10 months
2013-11 - 2014-08

Bachelor?s thesis

Frontend Developer Vanilla JavaScript HTML CSS
Frontend Developer
  • Worked with the Institute for Automation and Applied Informatics
  • Implemented user-friendly UI effectively presenting complex data and enhancing UX for visualizing the results of the project ?Extraction and Visualization of Semantic Concepts from Document-Sets using Taxonomy?
Vanilla JavaScript HTML CSS
KIT Karlsruhe
1 year 11 months
2011-09 - 2013-07

Leading mathematics practice courses

Software Architecture & Engineering Mentor and mathematics tutor Java EE JBoss (WildFly) Android ...
Software Architecture & Engineering Mentor and mathematics tutor
  • Led mathematics exercise classes for 20+ students per session, covering topics such as logic, algebra, limits, exponential functions, differential calculus, and numerical methods. Prepared sample exercises and reported student progress to the professor.
  • Tutored Programming I in C# teaching foundational programming concepts (e.g. data types, variables, control structures, data structures, functions, error handling, IO operations)
  • Guided 15 groups of 5 students on their curriculum project to develop Java EE web shop with REST APIs and Android frontend
  • Provided advice on database design, software architecture, and design patterns, assisting students in overcoming technical and programming challenges
Java EE JBoss (WildFly) Android Maven Eclipse REST API PostgreSQL Git JUnit Arquillian JMeter Jenkins Redmine
Karlsruhe University of Applied Sciences

Aus- und Weiterbildung

Aus- und Weiterbildung

2 years 7 months
2015-04 - 2017-10

Study - Business Information Systems

Master of Science, Technical University of Berlin, Germany
Master of Science
Technical University of Berlin, Germany
5 months
2016-02 - 2016-06

Exchange semester

University of Melbourne, Australia
University of Melbourne, Australia
1 month
2015-08 - 2015-08

Entrepreneurship and agribusiness intentions in the global economy

Bucharest Economic University, Romania
Bucharest Economic University, Romania
4 years 1 month
2011-03 - 2015-03

Study - Business Information Systems

Bachelor of Science, Karlsruhe University of Applied Sciences, Germany
Bachelor of Science
Karlsruhe University of Applied Sciences, Germany
1 month
2014-08 - 2014-08

Economy & politics

National Ching Hsing University, Taiwan
National Ching Hsing University, Taiwan
6 months
2013-08 - 2014-01

Exchange semester

California State University Fullerton, USA
California State University Fullerton, USA
1 month
2012-09 - 2012-09

Supply Chain Management and Simulation in Operations Management

TEI of Larissa, Greece
TEI of Larissa, Greece
1 year 4 months
2009-09 - 2010-12

German courses

A1 to C1, Reutlingen Adult Education Centre
A1 to C1
Reutlingen Adult Education Centre

Kompetenzen

Kompetenzen

Top-Skills

Node.js React Java Softwarearchitektur Software-Design TypeScript Fullstack Back-End Front-End Spring REST GraphQL

Produkte / Standards / Erfahrungen / Methoden

Profil
  • 10+ years of software development experience
  • Senior full stack engineer & software architect
  • Experienced as engineering leader & startup CTO

Web development
  • HTML5
  • CSS
  • React
  • GraphQL
  • REST
  • OData
  • SOAP
  • NodeJS
  • Java EE
  • Spring
  • SAPUI5
  • Meteor
  • AngularJS
  • ASP.NET

DevOps
  • Docker
  • Git
  • GitHub
  • GitHub actions
  • Jenkins
  • Team Foundation Server (TFS)

Modeling and design
  • UML
  • BPMN

Cloud services
  • AWS S3
  • AWS ElasticBean
  • AWS Fargate
  • AWS RDS
  • AWS ElastiCache
  • AWS CodePipeline
  • Azure Blob

Other
  • SAP Hybris
  • SAP Mobile Platform
  • Machine Learning
  • SCRUM
  • Design Patterns
  • Service Oriented Architecture (SOA)
  • Model-Driven Software Development (MDSD)
  • event-driven systems
  • Apache Hadoop
  • Apache Flink
  • Minio
  • Maven
  • Ant
  • Arquillian
  • JMeter

Programmiersprachen

Java
Python
C#
JavaScript
TypeScript

Datenbanken

SQL Server
MariaDB
MongoDB
PostgreSQL
Neo4j (Cypher)
Hibernate
Entity Framework

Einsatzorte

Einsatzorte

Berlin (+150km)
Deutschland, Schweiz
möglich

Projekte

Projekte

3 years 9 months
2021-04 - now

Building and scaling an industry-specific, multi-sided platform business

CTO and Co-founder GraphQL Node.js PostgreSQL ...
CTO and Co-founder
  • Co-founded Berlin-based headless, API-first, backend-as-a-service (BaaS) platform designed for developers to build and scale industry-specific, multi-sided platform business
  • Led technical strategy, event-driven architecture, system design, software, and runtime architecture hands-on
  • Built and managed a high-performing tech team, contributing hands-on to backend services, frontends, infrastructure automation (infrastructure-as-code), and CI/CD pipelines.
  • Active in technical pre-sales, solution engineering, customer implementation projects, supporting and training partners and customers? developers
  • Actively participated in business development, securing investors, speaking and representing the company at industry conferences
GraphQL Node.js PostgreSQL Redis React Material-UI AWS (Elastic Beanstalk; Fargate; Lambda; CloudFront; etc.) Docker Stripe integrations multi-tenancy event-driven architecture headless API-first
on request
9 years 4 months
2015-09 - now

Personal projects

  • Authored a blog about work, studies, and life in Germany, catering to an audience with origins in former Yugoslavia, attracting over 30,000 monthly readers
  • Organized professional meetups in Berlin, Munich, and Hamburg for IT professionals and entrepreneurs from former Yugoslavia and informal meetups for blog readers, fostering community engagement and networking
  • Hosted guest authors, sharing diverse experiences and perspectives on life in Germany, enriching the blog?s content and audience reach
  • Acted as a contact person for Serbian media, providing insights on Germany for interviews with various business magazines and mass-media outlets, including BBC Serbia and Blic
2 years
2019-04 - 2021-03

Decomposing a monolithic e-com application

Backend Software Engineer SAP Hybris Spring Boot Hibernate ...
Backend Software Engineer
  • Member of the eCommerce team tasked with decomposing a monolithic eCom application into microservices and extending the eCom system to enable SAP?s platform business
  • Implemented multiple microsevices deployed on a Kubernetes cluster managed by Kyma
  • Provided technical leadership to an outsourced team and coordinated integrations, ensuring smooth collaboration across multiple teams, functions, and cultures
  • Mentored junior developers
  • Designed private REST APIs, wrote Lambdas, tests, and contributed to frontend development and testing
SAP Hybris Spring Boot Hibernate MariaDB REST & OpenAPI (Swagger) Flowable (workflow engine) Gherkin & Cucumber Gherkin & Cypress Microservices Continuous Integration
SAP Berlin
2 years 8 months
2018-08 - 2021-03

B2C classifieds platform

Co-Founder & CTO Java Spring Boot MongoDB ...
Co-Founder & CTO
  • Co-founded a B2C subscription-based classifieds platform that connects compatriots and highlights their services and events. Built the tech, product, and business teams, then focused on leading the tech and product development.
  • Led the hands-on design of the entire system, including software and runtime architecture. Architected and implemented multiple front-end and back-end services
  • Mentored junior developers and led the entire development lifecycle and product delivery
  • Learned valuable lessons from hiring mistakes, a non-lean approach & over-engineering
Java Spring Boot MongoDB JUnit & Mockito Cucumber REST APIs Docker AWS (Fargate; S3; CloudFront; CodePipeline) React Material-UI Stripe API
on request
1 year 3 months
2018-01 - 2019-03

Building virtual banks within companies

Consultant for SAP Finance SAP In-House Cash (internal virtual bank) Payments and Electronic Bank Statements SAP Bank Communication Management ...
Consultant for SAP Finance
  • Member of the SAP finance consulting team, specialized in setting up virtual banks within corporations (in-house cash management), cash pooling, liquidity management, payment processing, and bank integrations.
  • Implemented SAP In-House Cash solutions, acting as a virtual internal bank to streamline internal cash management and optimize payment processing
  • Implemented PoC with SAP Cash Application (ML-based invoice matching automation)
  • Connected treasury management systems to banks, enhancing the efficiency of payment and electronic bank statement processing
  • Conducted workshops and training sessions on SAP In-House Cash, Bank Communication Management, and SAP Cash Application, leveraging machine learning for finance
SAP In-House Cash (internal virtual bank) Payments and Electronic Bank Statements SAP Bank Communication Management SAP Cash Application (Machine Learning in Finance)
SAP Berlin
11 months
2016-12 - 2017-10

Recommendation system for the SAP community platform

Machine Learning Applied Researcher Python Java JavaScript ...
Machine Learning Applied Researcher
  • Member of the SAP AI lab, developing proof-of-concepts for a recommender system for the SAP-Community platform using knowledge graphs and various machine learning models
  • Conducted compression of different models, including graph-based, content-based, and collaborative filtering approaches, designing and developing a hybrid recommender system
  • One of the PoCs demonstrated the practical application and transitioned into production
  • Authored and defended a master thesis titled ?A Hybrid Recommender System for Documents based on Enterprise Knowledge Graphs,? based on this work
Python Java JavaScript Jupyter Notebook Docker Neo4j Machine Learning Knowledge Graphs Recommender Systems Word2Vec Doc2Vec Node2Vec PathSim FastText TF-IDF Embeddings dimensionality reduction matrix factorization semantic analysis ranking dithering graph-theory PageRank ItemRank SimRank
SAP Berlin
5 months
2015-10 - 2016-02

S/4 HANA ERP system

Frontend Developer (working student) JavaScript SAPUI5 SDK OData Services ...
Frontend Developer (working student)
  • Collaborated with the SAP Solution Manager team to develop an MVP version of their existing SAP ECC product, tailored for the S/4 HANA ERP system, utilizing OData REST APIs for seamless integration
  • Successfully built the MVP for the ?Test Management Dashboard for S/4 HANA?s automated testing,? which was later expanded into the fully-fledged ?Test Suite Dashboard? product
JavaScript SAPUI5 SDK OData Services REST APIs SAP Fiori
SAP Berlin
5 months
2014-11 - 2015-03

Bachelor?s thesis

Full Stack Developer SAP Hybris Java Android ...
Full Stack Developer
  • Worked in the SAP fintech lab team, developing PoC integrations in eCom & mCom space
  • Built integrations to different payment methods (e.g. stored-value accounts, SMS & wallet payments) on wearables (Pebble Watch, Google Glass) and SAP Hybris-based online shops
  • Contributed to four patent applications, with one patent successfully approved
  • Authored a bachelor?s thesis titled ?Integration of an Omni-Channel Commerce Platform with a Mobile Payment Solution? based on this work
SAP Hybris Java Android JS REST & SOAP APIs Ant PostgreSQL PhoneGap
SAP Walldorf
8 months
2014-02 - 2014-09

Software solutions for different departments

Software Engineer and Team Lead C# .NET IIS Webserver ...
Software Engineer and Team Lead
  • Developed custom software solutions for various Audi departments, focusing on desktop Windows applications and web applications
  • Advocated for and successfully introduced web application development, Kanban and SCRUM to enhance development processes
  • Initially hired as a software engineer and quickly promoted to tech lead, overseeing three projects and managing a team of up to five developers
  • Led the team in the design and implementation of both web and desktop applications
C# .NET IIS Webserver SQL Server JavaScript HTML5 CSS Highcharts Team Foundation Server Entity Framework DevExpress WinForms Web Apps Desktop Apps
Wisio Ingolstadt
10 months
2013-11 - 2014-08

Bachelor?s thesis

Frontend Developer Vanilla JavaScript HTML CSS
Frontend Developer
  • Worked with the Institute for Automation and Applied Informatics
  • Implemented user-friendly UI effectively presenting complex data and enhancing UX for visualizing the results of the project ?Extraction and Visualization of Semantic Concepts from Document-Sets using Taxonomy?
Vanilla JavaScript HTML CSS
KIT Karlsruhe
1 year 11 months
2011-09 - 2013-07

Leading mathematics practice courses

Software Architecture & Engineering Mentor and mathematics tutor Java EE JBoss (WildFly) Android ...
Software Architecture & Engineering Mentor and mathematics tutor
  • Led mathematics exercise classes for 20+ students per session, covering topics such as logic, algebra, limits, exponential functions, differential calculus, and numerical methods. Prepared sample exercises and reported student progress to the professor.
  • Tutored Programming I in C# teaching foundational programming concepts (e.g. data types, variables, control structures, data structures, functions, error handling, IO operations)
  • Guided 15 groups of 5 students on their curriculum project to develop Java EE web shop with REST APIs and Android frontend
  • Provided advice on database design, software architecture, and design patterns, assisting students in overcoming technical and programming challenges
Java EE JBoss (WildFly) Android Maven Eclipse REST API PostgreSQL Git JUnit Arquillian JMeter Jenkins Redmine
Karlsruhe University of Applied Sciences

Aus- und Weiterbildung

Aus- und Weiterbildung

2 years 7 months
2015-04 - 2017-10

Study - Business Information Systems

Master of Science, Technical University of Berlin, Germany
Master of Science
Technical University of Berlin, Germany
5 months
2016-02 - 2016-06

Exchange semester

University of Melbourne, Australia
University of Melbourne, Australia
1 month
2015-08 - 2015-08

Entrepreneurship and agribusiness intentions in the global economy

Bucharest Economic University, Romania
Bucharest Economic University, Romania
4 years 1 month
2011-03 - 2015-03

Study - Business Information Systems

Bachelor of Science, Karlsruhe University of Applied Sciences, Germany
Bachelor of Science
Karlsruhe University of Applied Sciences, Germany
1 month
2014-08 - 2014-08

Economy & politics

National Ching Hsing University, Taiwan
National Ching Hsing University, Taiwan
6 months
2013-08 - 2014-01

Exchange semester

California State University Fullerton, USA
California State University Fullerton, USA
1 month
2012-09 - 2012-09

Supply Chain Management and Simulation in Operations Management

TEI of Larissa, Greece
TEI of Larissa, Greece
1 year 4 months
2009-09 - 2010-12

German courses

A1 to C1, Reutlingen Adult Education Centre
A1 to C1
Reutlingen Adult Education Centre

Kompetenzen

Kompetenzen

Top-Skills

Node.js React Java Softwarearchitektur Software-Design TypeScript Fullstack Back-End Front-End Spring REST GraphQL

Produkte / Standards / Erfahrungen / Methoden

Profil
  • 10+ years of software development experience
  • Senior full stack engineer & software architect
  • Experienced as engineering leader & startup CTO

Web development
  • HTML5
  • CSS
  • React
  • GraphQL
  • REST
  • OData
  • SOAP
  • NodeJS
  • Java EE
  • Spring
  • SAPUI5
  • Meteor
  • AngularJS
  • ASP.NET

DevOps
  • Docker
  • Git
  • GitHub
  • GitHub actions
  • Jenkins
  • Team Foundation Server (TFS)

Modeling and design
  • UML
  • BPMN

Cloud services
  • AWS S3
  • AWS ElasticBean
  • AWS Fargate
  • AWS RDS
  • AWS ElastiCache
  • AWS CodePipeline
  • Azure Blob

Other
  • SAP Hybris
  • SAP Mobile Platform
  • Machine Learning
  • SCRUM
  • Design Patterns
  • Service Oriented Architecture (SOA)
  • Model-Driven Software Development (MDSD)
  • event-driven systems
  • Apache Hadoop
  • Apache Flink
  • Minio
  • Maven
  • Ant
  • Arquillian
  • JMeter

Programmiersprachen

Java
Python
C#
JavaScript
TypeScript

Datenbanken

SQL Server
MariaDB
MongoDB
PostgreSQL
Neo4j (Cypher)
Hibernate
Entity Framework

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