Andrei K.
Bulgaria (UTC+02:00) 🇧🇬
Upstaffer since October 17, 2025

Andrei K. — Senior Backend Developer

Expertise in Back-End Web (11.0 yr.), DevOps (8.5 yr.).

Last verified on October 17, 2025

Core Skills

Java
Java
10 yr.
Kotlin
Kotlin
Spring
Spring Boot
Spring Boot
AWS
AWS
6 yr.

Bio Summary

Results-driven Senior Java Backend Developer with 11+ years of experience specialising in Java-based API integration and microservices architecture. Worked in international teams of 2–25 members, both on-site and remotely, with 3 years of proven team leadership. • Expertise: Kubernetes (AKS, AWS, GCP , OpenShift), cloud computing, enterprise integration platforms (EIP), and workflow automation. • Leadership: Successfully led teams, mentored developers, and drove the adoption of best practices in software design, CI/CD, and Agile methodologies (Scrum, Kanban).

Technical Skills

Programming Languages Java, Kotlin
Java Libraries and Tools Apache Camel
Android Libraries and Tools Kotlin
Java Frameworks Spring, Spring Boot
Databases & Management Systems / ORM MongoDB, PostgreSQL
Cloud Platforms, Services & Computing AWS, GCP
Azure Cloud Services AKS
Amazon Web Services AWS CloudWatch, AWS CodePipeline, AWS EventBridge, AWS Lambda, AWS Route 53, AWS SQS, AWS VPC
SDK / API and Integrations Keycloak, OAuth
Virtualization, Containers and Orchestration Kubernetes
Message/Queue/Task Brokers RabbitMQ
Other Technical Skills Apache Kafka, BPMN Camunda, IAM, Openshift Cloud Platform, RDS

Work Experience

Senior Java Backend Developer | Full Stack, Construction site management

Duration: February 2020 – September 2025

Summary: Led the development of an in-house software platform IRIS for central management of construction site documentation and data, significantly enhancing performance, scalability, system responsiveness, and reliability through technical improvements and mentoring.

Responsibilities: Rewrote the synchronization service, reduced API response time, designed and built microservices from scratch, optimized access control, achieved high unit test coverage, resolved technical issues leading to zero technical debt, led migration from monolith to microservices, developed critical microservices on Java Spring Boot, led PoC solutions, implemented CI/CD pipelines, optimized cloud infrastructure and system performance, implemented Keycloak for OAuth2 and SSO, provided technical expertise, authored technical documentation, and trained new hires.

Technologies: Kotlin, Java 21, Spring, PostgreSQL, MongoDB, RabbitMQ, Redis, AWS EKS, S3, RDS, SQS, CloudWatch, EC2, CodePipeline, EventBridge, Lambda, IAM, VPC, Route 53, ACM

Senior Java Backend Developer | Tech Lead, Banking and insurance services

Duration: August 2014 – February 2020

Summary: Spearheaded the development and launch of a multitude of banking products, driving integration, rebuilding the core EIP, migrating to ELK and Kafka, redesigning BPMN diagrams, and decomposing a monolithic Red Hat JBoss Fuse project into microservices.

Responsibilities: Delivered integration services for major banks, rebuilt EIP core, moved search from PostgreSQL to ELK, migrated messaging from IBM WMQ to Kafka, designed BPMN diagrams, led backend teams, promoted from Junior Developer to Lead Developer, optimized monolithic applications, developed high-load data processing systems, built reactive microservices, implemented DevOps initiatives, and developed workflows with Camunda.

Technologies: Java 17, Kotlin, Spring, PostgreSQL, MongoDB, Apache Kafka, Camunda BPMN, Kubernetes, OpenShift, Apache Camel

Education

  • Master's Degree in Computer Science
  • Voronezh State Technical University
  • 2014

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