Recommended expert

Alexander Kapincev

Senior Fullstack Developer

Alexander Kapincev
Darmstadt, Germany

Experience

Sep 2024 - Present
1 year 5 months

Senior Fullstack Developer

Deutsche Vermögensberatung AG (DVAG)

  • Further development and maintenance of a complex sales platform focused on digital closing processes, customer portal interactions, and document generation for financial and insurance products
  • Development and maintenance of microservices with Spring Boot 3 and Kotlin
  • Frontend development with Angular 20 to display products, applications, and documents
  • Conducting end-to-end tests with Playwright and integration tests with WireMock
  • Creating and optimizing Quartz jobs and CronJobs
  • Refactoring the security configuration in a multi-realm Keycloak setup with custom FilterChain, permission evaluator, and factory routing
  • Creating dynamic emails with Thymeleaf
  • Extensive error analysis with Application Insights, Log Analytics, and direct SQL debugging
  • Introducing a dynamically controllable security architecture with flexible token processing based on path and realm
  • Stabilizing and clearly structuring the closing process for complex product models
  • Significantly increased maintainability and readability of code through modular refactorings
  • Improved test stability and depth by combining Playwright, WireMock, and integration tests
  • Targeted performance optimization through analysis of Hibernate statistics, query tuning, and use of SQL execution plans
  • Technologies used: Java 21, Kotlin, Spring Boot 3, Angular, TypeScript, REST API, JSON, Kubernetes, Docker, PostgreSQL, Liquibase, Keycloak, OAuth2, GitHub Actions, Testcontainers, Azure Application Insights, Thymeleaf, Tilt, Microsoft SQL Server
Oct 2023 - Sep 2024
1 year

Senior Fullstack Developer

Fraunhofer-Institut für Experimentelles Software Engineering IESE

  • Development of a digital platform in the BMEL-funded project "Smarte.Land.Regionen" to promote digitization in rural areas
  • Implementation of microservices with Spring Boot 2/3 and Java 19
  • Extensive frontend development with React including creating and extending numerous components
  • Integration of a payment service provider (Secupay) and full automation of payment processing
  • Migration of existing systems to newer versions and restructuring of the database schema using Liquibase
  • Creation and implementation of user stories
  • Significant improvement of the user interface and user experience through custom React components
  • Successful migration from Spring Boot 2 to 3 and increased test coverage with Testcontainers
  • Contribution to improving platform efficiency and user satisfaction
  • Technologies used: Java 19, Spring Boot 2/3, React, TypeScript, JavaScript, REST API, JSON, Kubernetes, Docker, PostgreSQL, Liquibase, Keycloak, GitLab CI, Testcontainers, GreenMail, Thymeleaf
Jul 2022 - Sep 2023
1 year 3 months

Senior Fullstack Developer

Techem X GmbH

  • Revolutionizing the private customer business with fully digital solutions for heating cost billing and smoke detector management
  • Designing and developing cloud-native backend systems on the Azure platform
  • Implementing microservices with Spring Boot 3 and Java 17/19
  • Integrating various third-party systems (Heiztec, Ortec, SAP, Microsoft Calendar, CRM)
  • Developing GraphQL interfaces and Kubernetes configurations
  • Designing and implementing complex business logic for billing and device management processes
  • Implementing Azure Functions
  • Contributing to frontend development with React
  • Successfully digitizing and automating the customer acquisition process
  • Migrating the entire system to Kubernetes for improved scalability and maintainability
  • Technologies used: Java 17/19, Spring Boot 2/3, Azure Cloud, Terraform, Docker, Kubernetes, Helm, Grafana, PostgreSQL, Cosmos DB, MS SQL, Drools (BRMS), GraphQL, React, GitLab CI, Testcontainers, SOAP, XML, WSDL, REST API, Application Insights
Jul 2021 - Jul 2022
1 year 1 month

Senior Fullstack Developer

DG Verlag / DGNexolution

  • Further development of an e-accounting tool for cooperative banks to generate and process electronic invoice data online
  • Development of an MVP for a sustainability portal to support sustainable businesses
  • Implementing new features and requirements in the e-accounting tool and introducing a new invoice data format for Atruvia
  • Backend development with Spring Boot 2 and Java 11/Kotlin, frontend development with Angular 13
  • Developing Magnolia CMS apps, REST endpoints, and light modules
  • Integrating Hibernate Search and Lucene and implementing security measures with Spring ACL
  • Database design and optimization with PostgreSQL and Ltree
  • Successful rollout of the new invoice data format and production launch of the MVP
  • Technologies used: Java 11, Kotlin, Spring Boot 2, TypeScript, Angular 13, Docker, Kubernetes, Spring ACL, PostgreSQL, Hibernate Search, Lucene, Magnolia, REST API, JSON
Apr 2021 - Jun 2021
3 months

Fullstack Developer

DB Regio Bus

  • Further development of a cloud-based data lake and integration platform for digital transformation
  • Analyzing and assessing data quality and transformations for data cleansing
  • Designing and implementing a Java-based microservice for CSV and XML processing
  • Adapting and optimizing existing Python and Groovy modules
  • Developing a Groovy script to automate user imports into the Tenfold system
  • Integrating security measures with Keycloak and containerization with Docker
  • Successful implementation and production deployment of the Java microservice and automation of user imports
  • Technologies used: Java 8, Spring Boot 2, Python, Groovy, JavaScript, Linux shell, Keycloak, Docker, Tenfold, SOAP, REST API, XML, JSON
Dec 2019 - Mar 2021
1 year 4 months

Fullstack Developer

Unzer GmbH

  • Modernization and automation of data import processes for the standard debtor management and billing system
  • Designed the software architecture for the new import solution
  • Developed microservices with Java and Spring Boot 2 and implemented complex business logic
  • Set up and optimized CI/CD pipelines with GitLab CI and Jenkins
  • Integrated Keycloak using OpenID Connect and implemented message queue-based communication with ActiveMQ and Kafka
  • Automated merchant data imports and deployed to AWS Cloud
  • Significantly reduced manual interventions and improved scalability and data security
  • Technologies used: Java 11, Spring Boot 2, Spring Cloud Config, AWS (SQS, SNS, DynamoDB), MariaDB, ActiveMQ, Apache Kafka, Maven, Keycloak, OAuth2, Testcontainers, Docker, Kubernetes, GitLab CI, Jenkins, REST API, JSON
Mar 2019 - Dec 2019
10 months

Fullstack Developer

Unzer GmbH

  • Developed the Merchant Onboarding Service Hub (MOSH) to automate the merchant onboarding process
  • Backend development with Java and Spring Boot 2, frontend with Angular 8 and Bootstrap 4
  • Implemented complex business logic and modeling with Flowable
  • Integrated Keycloak using OpenID Connect
  • Set up and optimized CI/CD pipelines
  • Developed and integrated AWS services (DynamoDB, SQS, SNS, S3)
  • Launched the MVP in September 2020 for self-onboarding capability and continuously expanded the processes
  • Technologies used: Java 8, Spring Boot 2, Angular 8, Bootstrap 4, AWS (DynamoDB, SQS, SNS, S3), Elastic Beanstalk, Flowable, Keycloak, Docker, Kubernetes, Testcontainers, GitLab, Jenkins, SonarQube, Postman, REST API, JSON
Jan 2019 - Mar 2019
3 months

Fullstack Developer

Detim Consulting GmbH

  • Further developed a web application for managing employee data
  • Backend development with Java and Spring Boot 2, implementing complex business logic
  • Developed and optimized RESTful APIs
  • Frontend development with Angular 6 and responsive interfaces using HTML and SCSS
  • Integrated Keycloak using OAuth 2.0 and optimized the database with Hibernate
  • Implemented continuous integration and version control with Git and BitBucket
  • Improved the UI, made backend services more efficient, and increased security
  • Technologies used: Java 8, Spring Boot 2, Angular 6, Hibernate, Maven, HTML, SCSS, Keycloak, OAuth 2.0, Git, BitBucket, REST API, JSON
Feb 2018 - Dec 2018
11 months

Fullstack Developer

Deutsche Telekom

  • Enhanced and adapted the cBSI platform for automated business process integration in customer care & billing
  • Backend development with Java 7, Java EE, and implemented business logic
  • Developed and extended web services and frontends using JavaServer Faces and ICEfaces
  • Adapted and migrated C++ adapters to Java
  • Developed shell scripts for automatic processing of CSV files
  • Supported the rollout and deployment of new features
  • Successfully migrated C++ adapters, extended platform functionality, and improved integration
  • Technologies used: Java 7, Java EE, C++, JBoss, Hibernate, Oracle DB, JavaServer Faces, ICEfaces, HTML, CSS, JavaScript, Linux Shell, SED, Subversion, SOAP, XML, JSON, REST API

Summary

As an experienced fullstack developer and cloud engineer, I bring a wide range of experience and skills in implementing distributed systems and cloud applications. My many years of expertise include developing microservices with Java and Spring Boot as well as integrating cloud technologies such as AWS and Azure.

My expertise covers the entire Java ecosystem, modern web development with Angular and React, as well as DevOps practices with Docker and Kubernetes. I have extensive knowledge in CI/CD, database design (relational and NoSQL), security implementations, and messaging systems.

Skills

  • Java Ecosystem: Java 8-24, Kotlin, Spring Boot 2+, Spring (Data, Cloud, Mvc, Security), Jpa/hibernate

  • Web Development: Angular, React, Typescript, Javascript, Html5, Css

  • Cloud & Devops: Aws, Azure, Docker, Kubernetes, Helm, Terraform

  • Ci/cd: Gitlab Ci, Github Actions, Jenkins, Maven, Gradle, Git

  • Agile Methods: Experience In Scrum/kanban Projects

  • Architecture And Planning: Knowledge In Architecture, Planning, Execution, Quality Assurance Of Complex Software Solutions.

  • Databases: Design And Construction Of Relational And Nosql Databases (Postgresql, Mysql, Mariadb, Oracledb, Dynamodb, Mongodb, Cosmosdb)

  • Programming Languages: Java 8-24, Typescript, Javascript, Kotlin, Python

  • Web And Frontend Development: Angular 2+, React, Html5, Bootstrap 4+, Css, Scss, Sass, Nodejs, Npm, Freemarker / Thymeleaf

  • Backend Development: Spring Boot 2+, Spring Data, Spring Cloud, Spring Security, Spring Acl, Jpa / Hibernate, Liquibase, Apache Pdfbox, Quartz

  • Devops: Docker, Terraform, Kubernetes (Helm, Kustomize), Linux Shell, Grafana, Prometheus, Tilt

  • Ci/cd: Gitlab Ci, Github Actions, Jenkins, Maven, Gradle, Git

  • Databases: Mysql, Mariadb, Oracle Db, Postgresql/postgis, Dynamodb, Mongodb, Cosmos Db, Azure Sql

  • Cloud Computing: Aws (S3, Cloudfront, Ecs, Ec2, Eb, Rds, Lambda), Azure (Azure Functions, Cosmos Db, Azure Blob Storage, Application Insights, Aks, Workbooks, Key Vault)

  • Security: Keycloak, Azure Ad, Json Web Token, Oauth 2.0, Openid Connect, Spring Acl

  • Communication: Rest Api, Graphql, Soap, Websocket, Activemq, Aws Sns/sqs, Azure Service Bus, Azure Event Grids, Kafka

  • Search Engine: Hibernate Search, Lucene

  • Test / Quality Management: Junit 5, Mockito, Wiremock, Playwright, Selenide, Selenium, Sonarqube, Openapi/swagger, Testcontainers

  • Tools / Standard Software: Intellij Idea, Atlassian Jira, Confluence, Openlens, Plantuml, Postman

Languages

German
Native
English
Advanced

Education

Oct 2016 - Sep 2018

Hochschule Darmstadt

M.Sc. in Computer Science · Computer Science · Darmstadt, Germany

Oct 2012 - Sep 2016

Hochschule Darmstadt

B.Sc. in Computer Science · Computer Science · Darmstadt, Germany

Certifications & licenses

Certified Kubernetes Application Developer

Terraform Certified Associate HOTAO-003

Need a freelancer? Find your match in seconds.
Try FRATCH GPT
More actions

Similar Freelancers

Discover other experts with similar qualifications and experience

Hüseyin Korkut
Hüseyin Korkut

Senior Full-Stack Engineer

View Profile
Thomas Jarnot
Thomas Jarnot

Backend Developer, DevOps Engineer

View Profile
Werner Keil
Werner Keil

Test Coordinator, Designer and Engineer

View Profile
Martin Eisengardt
Martin Eisengardt

Software Developer

View Profile
Achille Chimi
Achille Chimi

Backend/Frontend Developer

View Profile
Robin Sadlo
Robin Sadlo

Senior Cloud & Backend Engineer

View Profile
Dirk Bolte
Dirk Bolte

Senior Software Developer

View Profile
Ulrich Cech
Ulrich Cech

Java Architect/Developer – Freelancer

View Profile
Michael König
Michael König

Architect and Full-Stack Developer

View Profile
Thomas Hoefkens
Thomas Hoefkens

Senior MLOps, DevOps Engineer

View Profile
Jürgen Fey
Jürgen Fey

AR/VR/XR Architect

View Profile
Jan Mönnich
Jan Mönnich

Interface project at HR Solutions GmbH for Rhineland-Palatinate / BAMF

View Profile
Markus Glagla
Markus Glagla

Full Stack Developer

View Profile
Johannes Erchen
Johannes Erchen

Senior Application Developer

View Profile
Rainer Bieniek
Rainer Bieniek

Senior Developer

View Profile
Tilo Kowalski
Tilo Kowalski

Backend Developer

View Profile
Jan Lüders
Jan Lüders

Senior Developer

View Profile
Marijn Scholtens
Marijn Scholtens

Senior Software Engineer

View Profile
Florian Fladung
Florian Fladung

Senior Backend Developer

View Profile
Slava Schmidt
Slava Schmidt

Senior Technical Lead

View Profile
Rainer Diekmann
Rainer Diekmann

Enterprise Architecture Management / Software Developer Backend

View Profile
Benedikt Buchner
Benedikt Buchner

Fullstack Developer

View Profile
Stefan Baust
Stefan Baust

Senior Full Stack Developer / Co-Founder / CTO / Head of Development

View Profile
Sebastian Kanzow
Sebastian Kanzow

Senior Lead Developer, System Architecture

View Profile
Wolfram Rittmeyer
Wolfram Rittmeyer

Backend and Flutter App Developer

View Profile
Meik Schindler
Meik Schindler

Freelance Trainer & Consultant

View Profile
Rodrigue Kelen-yo
Rodrigue Kelen-yo

Fullstack Development

View Profile
Thomas Ramm
Thomas Ramm

Architect, Developer

View Profile
Rüdiger Schulz
Rüdiger Schulz

Full-Stack Software Engineer / Consultant for Digitalization

View Profile
Lothar Hinsche
Lothar Hinsche

Solution Manager for PoC investigation and replacement and refinement of an existing cloud and IoT power plant control system

View Profile