Backend Architect focused on data consistency, scalability, and production reliability in Java-based enterprise systems
Aktualisiert am 10.02.2026
Profil
Freiberufler / Selbstständiger
Remote-Arbeit
Verfügbar ab: 10.02.2026
Verfügbar zu: 100%
davon vor Ort: 10%
Java Backend Architecture
Microservices
AWS
Spring Boot
Distributed Systems
Data Consistency
PostgreSQL
Apache Kafka
REST APIs
Event-Driven Architecture
Docker
Kubernetes
CI/CD
Git
Cloud Architecture
English
Verhandlungssicher
Ukrainian
Muttersprache
Russian
Muttersprache

Einsatzorte

Einsatzorte

Deutschland, Schweiz, Österreich
möglich

Projekte

Projekte

1 year 1 month
2025-03 - now

Migrated large-scale financial data flows

Senior Backend Developer Kotlin/Java Spring Boot PostgreSQL ...
Senior Backend Developer
  • Migrated large-scale financial data flows from PostgreSQL to Azure Synapse ? improved performance and throughput.
  • Designed and optimized pipelines for high-volume financial calculations.
  • Identified critical bottlenecks and introduced backend improvements.
  • Contributed to backend design and implementation of core financial products.
Kotlin/Java Spring Boot PostgreSQL k8s Azure
SAP Fioneer (remotely)
1 year 6 months
2023-09 - 2025-02

Architected and developed Video Identification E2E onboarding system

Senior Java Backend Engineer Java 17 Spring Boot PostgreSQL ...
Senior Java Backend Engineer
  • Architected and developed Video Identification E2E onboarding system for new customers.
  • Designed Signature Verification E2E workflow.
  • Created backend components for a new digital Bank Card product.
  • Worked closely with backend, DevOps and QA teams on end-to-end feature delivery.
Java 17 Spring Boot PostgreSQL Redis Kafka Microservices Kubernetes Camunda
Raif eisen Bank (remotely)
Remote (EU)
11 months
2022-08 - 2023-06

Investigated and fixed long-term production memory leaks

Senior Backend Engineer Java 11/14 Tomcat Weblogic ...
Senior Backend Engineer
  • Investigated and fixed long-term production memory leaks in core systems.
  • Designed and delivered a new fraud-prevention microservice from scratch.
  • Performed deep security audits and architectural improvements for enterprise-grade telecom products.
  • Supported production releases in collaboration with the Operations team.
  • Accomplished detailed source code analysis for Security Vulnerabilities.
Java 11/14 Tomcat Weblogic Spring Boot Hibernate REST Kafka Messaging Microservices JUnit PowerMock
Syniverse (REW Technology), USA (remotely)
4 years 3 months
2017-01 - 2021-03

Implemented AWS-based backend services

Senior Backend Engineer Node.js TypeScript AWS (Neptune/ DynamoDB/ CDK/ Lambda/ API Gateway) ...
Senior Backend Engineer
  • Implemented AWS-based backend services for a cost optimization engine.
  • Defined cloud infrastructure with AWS CDK; implemented serverless microservices.
  • Coordinated backend & frontend technical roadmap.
  • Involved in covering the full lifecycle of telecom billing real-time and offline charging systems.
  • Improved monolith system start time.
  • Managed k8s cluster.
Node.js TypeScript AWS (Neptune/ DynamoDB/ CDK/ Lambda/ API Gateway) BDD Java 11 JBoss Quartz Kubernetes JUnit
Optiva (Crossover), USA (remotely)
2 years 1 month
2015-01 - 2017-01

moved the multi-tenant emergency

Senior Backend Engineer Java AWS (EC2/ VPC/ S3/ ElasticCache) DevOps ...
Senior Backend Engineer
  • Successfully moved the multi-tenant emergency and mass notification system from bare-metal to AWS.
  • Dockerized most of the system.
Java AWS (EC2/ VPC/ S3/ ElasticCache) DevOps Linux Docker PostgreSQL Restlet Redis Angular
MessageOne (Crossover), USA (remotely)
2 years 5 months
2013-01 - 2015-05

Built enterprise e-commerce solution on Hybris

Senior Software Engineer Java Hybris SAP ...
Senior Software Engineer
  • Built enterprise e-commerce solution on Hybris from the ground up.
  • Designed integrations using Camel/JMS and optimized backend performance.
Java Hybris SAP Spring JSP Camel JMS ElasticSearch Solr FuseESB JUnit Ant/Maven SVN
Bobcat (Farata Systems), USA (remotely)
2 years 5 months
2010-09 - 2013-01

Designed new APIs

Senior Software Engineer Java/.NET Eclipse/Visual Studio JUnit/NUnit ...
Senior Software Engineer
  • Designed new APIs for LaTeX-to-PDF and PDF-to-LaTeX.
  • Refactored legacy subsystems for performance and memory efficiency.
Java/.NET Eclipse/Visual Studio JUnit/NUnit Ant/NAnt SVN JIRA TeamCity EMMA R# Sonar StyleCop MySQL Mina/NIO Spring Hibernate SQL Maven JavaScript/JQuery Jetty Tomcat
Aspose Pty Ltd, Australia (remotely)
3 years 4 months
2006-08 - 2009-11

Integrated flagman project

Software Engineer Java 4 Eclipse/JDE Ant ...
Software Engineer
  • Integrated flagman project IM+® on BlackBerry® devices with Skype® and Twitter® as new communication channels.
  • Launched Push notifications for MIDP / BlackBerry phones.
  • Created from scratch GPS based application (GPSed®) for MIDP phones.
Java 4 Eclipse/JDE Ant CVS JIRA Bugzilla
SHAPE Services GmbH, Germany (Ukraine, Odessa)

Aus- und Weiterbildung

Aus- und Weiterbildung

2002 - 2008

MS in Applied Mathematics and Computer Science

Odessa National University named after I. I. Mechnikov, Odessa, Ukraine

Kompetenzen

Kompetenzen

Top-Skills

Java Backend Architecture Microservices AWS Spring Boot Distributed Systems Data Consistency PostgreSQL Apache Kafka REST APIs Event-Driven Architecture Docker Kubernetes CI/CD Git Cloud Architecture

Produkte / Standards / Erfahrungen / Methoden

Profile

  • Senior Java Backend Engineer with hands-on experience in enterprise backend systems.
  • Hands-on background in Java, Spring Boot, microservices and event-driven architectures.
  • Experience with large-scale systems in FinTech and Telecom.
  • Focused on building stable, maintainable backend services in long-term B2B projects.


SKILLS

  • Backend Engineering: Java, Spring Boot, Microservices, Kafka, REST, SQL
  • Cloud & DevOps: Kubernetes, Docker, CI/CD, Cloud (AWS, Azure)
  • Infrastructure & Observability: Logging, monitoring, tracing, disaster recovery, load balancing, caching strategies
  • Testing: JUnit, Mockito, TestContainers, Kotest
  • Architecture & System Design: Fault-tolerant systems, high availability, distributed systems, event-driven architecture

Einsatzorte

Einsatzorte

Deutschland, Schweiz, Österreich
möglich

Projekte

Projekte

1 year 1 month
2025-03 - now

Migrated large-scale financial data flows

Senior Backend Developer Kotlin/Java Spring Boot PostgreSQL ...
Senior Backend Developer
  • Migrated large-scale financial data flows from PostgreSQL to Azure Synapse ? improved performance and throughput.
  • Designed and optimized pipelines for high-volume financial calculations.
  • Identified critical bottlenecks and introduced backend improvements.
  • Contributed to backend design and implementation of core financial products.
Kotlin/Java Spring Boot PostgreSQL k8s Azure
SAP Fioneer (remotely)
1 year 6 months
2023-09 - 2025-02

Architected and developed Video Identification E2E onboarding system

Senior Java Backend Engineer Java 17 Spring Boot PostgreSQL ...
Senior Java Backend Engineer
  • Architected and developed Video Identification E2E onboarding system for new customers.
  • Designed Signature Verification E2E workflow.
  • Created backend components for a new digital Bank Card product.
  • Worked closely with backend, DevOps and QA teams on end-to-end feature delivery.
Java 17 Spring Boot PostgreSQL Redis Kafka Microservices Kubernetes Camunda
Raif eisen Bank (remotely)
Remote (EU)
11 months
2022-08 - 2023-06

Investigated and fixed long-term production memory leaks

Senior Backend Engineer Java 11/14 Tomcat Weblogic ...
Senior Backend Engineer
  • Investigated and fixed long-term production memory leaks in core systems.
  • Designed and delivered a new fraud-prevention microservice from scratch.
  • Performed deep security audits and architectural improvements for enterprise-grade telecom products.
  • Supported production releases in collaboration with the Operations team.
  • Accomplished detailed source code analysis for Security Vulnerabilities.
Java 11/14 Tomcat Weblogic Spring Boot Hibernate REST Kafka Messaging Microservices JUnit PowerMock
Syniverse (REW Technology), USA (remotely)
4 years 3 months
2017-01 - 2021-03

Implemented AWS-based backend services

Senior Backend Engineer Node.js TypeScript AWS (Neptune/ DynamoDB/ CDK/ Lambda/ API Gateway) ...
Senior Backend Engineer
  • Implemented AWS-based backend services for a cost optimization engine.
  • Defined cloud infrastructure with AWS CDK; implemented serverless microservices.
  • Coordinated backend & frontend technical roadmap.
  • Involved in covering the full lifecycle of telecom billing real-time and offline charging systems.
  • Improved monolith system start time.
  • Managed k8s cluster.
Node.js TypeScript AWS (Neptune/ DynamoDB/ CDK/ Lambda/ API Gateway) BDD Java 11 JBoss Quartz Kubernetes JUnit
Optiva (Crossover), USA (remotely)
2 years 1 month
2015-01 - 2017-01

moved the multi-tenant emergency

Senior Backend Engineer Java AWS (EC2/ VPC/ S3/ ElasticCache) DevOps ...
Senior Backend Engineer
  • Successfully moved the multi-tenant emergency and mass notification system from bare-metal to AWS.
  • Dockerized most of the system.
Java AWS (EC2/ VPC/ S3/ ElasticCache) DevOps Linux Docker PostgreSQL Restlet Redis Angular
MessageOne (Crossover), USA (remotely)
2 years 5 months
2013-01 - 2015-05

Built enterprise e-commerce solution on Hybris

Senior Software Engineer Java Hybris SAP ...
Senior Software Engineer
  • Built enterprise e-commerce solution on Hybris from the ground up.
  • Designed integrations using Camel/JMS and optimized backend performance.
Java Hybris SAP Spring JSP Camel JMS ElasticSearch Solr FuseESB JUnit Ant/Maven SVN
Bobcat (Farata Systems), USA (remotely)
2 years 5 months
2010-09 - 2013-01

Designed new APIs

Senior Software Engineer Java/.NET Eclipse/Visual Studio JUnit/NUnit ...
Senior Software Engineer
  • Designed new APIs for LaTeX-to-PDF and PDF-to-LaTeX.
  • Refactored legacy subsystems for performance and memory efficiency.
Java/.NET Eclipse/Visual Studio JUnit/NUnit Ant/NAnt SVN JIRA TeamCity EMMA R# Sonar StyleCop MySQL Mina/NIO Spring Hibernate SQL Maven JavaScript/JQuery Jetty Tomcat
Aspose Pty Ltd, Australia (remotely)
3 years 4 months
2006-08 - 2009-11

Integrated flagman project

Software Engineer Java 4 Eclipse/JDE Ant ...
Software Engineer
  • Integrated flagman project IM+® on BlackBerry® devices with Skype® and Twitter® as new communication channels.
  • Launched Push notifications for MIDP / BlackBerry phones.
  • Created from scratch GPS based application (GPSed®) for MIDP phones.
Java 4 Eclipse/JDE Ant CVS JIRA Bugzilla
SHAPE Services GmbH, Germany (Ukraine, Odessa)

Aus- und Weiterbildung

Aus- und Weiterbildung

2002 - 2008

MS in Applied Mathematics and Computer Science

Odessa National University named after I. I. Mechnikov, Odessa, Ukraine

Kompetenzen

Kompetenzen

Top-Skills

Java Backend Architecture Microservices AWS Spring Boot Distributed Systems Data Consistency PostgreSQL Apache Kafka REST APIs Event-Driven Architecture Docker Kubernetes CI/CD Git Cloud Architecture

Produkte / Standards / Erfahrungen / Methoden

Profile

  • Senior Java Backend Engineer with hands-on experience in enterprise backend systems.
  • Hands-on background in Java, Spring Boot, microservices and event-driven architectures.
  • Experience with large-scale systems in FinTech and Telecom.
  • Focused on building stable, maintainable backend services in long-term B2B projects.


SKILLS

  • Backend Engineering: Java, Spring Boot, Microservices, Kafka, REST, SQL
  • Cloud & DevOps: Kubernetes, Docker, CI/CD, Cloud (AWS, Azure)
  • Infrastructure & Observability: Logging, monitoring, tracing, disaster recovery, load balancing, caching strategies
  • Testing: JUnit, Mockito, TestContainers, Kotest
  • Architecture & System Design: Fault-tolerant systems, high availability, distributed systems, event-driven architecture

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