Backend software engineering with Java and Spring Boot ? building and maintaining RESTful APIs, working with MongoDB/relational databases, and writing
Aktualisiert am 15.07.2026
Profil
Freiberufler / Selbstständiger
Verfügbar ab: 15.07.2026
Verfügbar zu: 100%
davon vor Ort: 100%
Java 21
Spring Boot
Microservices

Einsatzorte

Einsatzorte

Heidelberg (+75km)
Deutschland
nicht möglich

Projekte

Projekte

3 Jahre 11 Monate
2022-06 - 2026-04

Built and operated event-driven microservices

Lead/Senior Backend & Full-Stack Engineer
Lead/Senior Backend & Full-Stack Engineer
  • Owned backend domains end-to-end within T-Mobile's large, established T-Life codebase ? a high-scale, real-time consumer SaaS platform handling millions of concurrent requests ? working independently from problem framing through rollout
  • Built and operated event-driven microservices (Java, Spring Boot 3.x, Apache Kafka, RabbitMQ), communicating synchronously via REST and asynchronously via Kafka for high-throughput event fan-out between services
  • Designed and consumed REST/GraphQL/gRPC APIs encapsulating complex business logic for consumption across hundreds of internal services; enforced contract-first, OpenAPI-documented development and resilience patterns
  • Designed and scaled high-concurrency systems on PostgreSQL and MySQL: sharding strategy, transaction management, index tuning, and query optimisation under peak production load, maintaining sub-millisecond read paths
  • Drove $24M annual savings by scoping, designing, and implementing a custom high-concurrency API Gateway (Java/Spring Boot/REST), owned end-to-end from business problem to production; recognised by VP of Engineering
  • Provisioned and right-sized Kubernetes infrastructure (EKS/GKE-compatible) with Terraform on AWS; established Grafana/Prometheus/Datadog observability, achieving 40% cloud cost reduction
  • Practised and led TDD discipline across the team (JUnit 5, Mockito, Testcontainers) and enforced SonarQube quality gates and code-review standards in GitLab CI/CD; mentored junior engineers
  • Communicated clearly in English with distributed, cross-functional, international teams across multiple time zones; authored ADRs and architectural documentation
UST India Pvt Ltd (Client: T-Mobile USA)
1 Jahr 5 Monate
2021-02 - 2022-06

Led decomposition of a large Java monolith into independently deployable microservices

Senior Associate Consultant
Senior Associate Consultant
  • Led decomposition of a large Java monolith into independently deployable microservices for a complex automotive-diagnostics platform using CQRS, DDD, event-driven architecture (Apache Kafka), Docker, and Kubernetes, achieving a 70% server cost reduction with zero live-business disruption
  • Optimised Oracle and PostgreSQL databases: schema redesign, PL/SQL and JDBC-level tuning, transaction and locking analysis, sharding-aware indexing, and query analysis to support high-concurrency, high-throughput workloads
  • Implemented resilience patterns for unreliable third-party upstreams; automated ETL pipelines with Spring Batch; maintained high integration test coverage with Testcontainers in CI.
Infosys Pvt Ltd
2 Jahre
2019-03 - 2021-02

Designed and built a Java/Spring Boot automated migration engine

Software Engineer
Software Engineer
  • Designed and built a Java/Spring Boot automated migration engine for a global airline cargo management platform (REST APIs, SOAP integrations, Oracle DB, MongoDB) within a large legacy codebase; owned end-to-end from business scoping through implementation, testing, release, and maintenance
  • Delivered 200+ backend features in Scrum, working end-to-end across a complex multi-airline domain; contributed to 20% growth in global airline customer base through scalable, high-throughput system design
IBS Software
3 Jahre 6 Monate
2015-09 - 2019-02

Developed Java enterprise applications and REST/SOAP APIs

Software Engineer
Software Engineer
  • Developed Java enterprise applications and REST/SOAP APIs for logistics and e-commerce clients; designed relational (MySQL, Oracle) and NoSQL (MongoDB) data models for high-concurrency workloads
  • Introduced JUnit/Mockito TDD as a team-wide testing standard; diagnosed and resolved critical distributed system performance issues to maintain SLA compliance under production load
Pitsolutions

Aus- und Weiterbildung

Aus- und Weiterbildung

2011 ? 2015

B.Tech in Computer Science & Engineering ? Rajiv Gandhi Institute of Technology, Kerala, India

Kompetenzen

Kompetenzen

Top-Skills

Java 21 Spring Boot Microservices

Produkte / Standards / Erfahrungen / Methoden

PROFESSIONAL SUMMARY

Backend Software Engineer with 10+ years of production experience building and operating business-critical Java services (Java 8?23, including Java 17+) at high scale within large, established codebases. Strong track record designing and consuming REST APIs, building microservices and event-driven distributed systems with Apache Kafka and RabbitMQ, and owning technical solutions independently from problem framing through production rollout. Practises strong software engineering fundamentals ? TDD, code review, CI/CD ? and has set these standards across teams, not just followed them. Comfortable with Spring Boot, AWS, and Kubernetes in production, and experienced translating infrastructure and reliability work into measurable outcomes ($24M and 70% cost reductions). Clear, professional English communicator with hands-on interest in applying AI/ML to engineering workflows, including building production LLM-integrated systems.


CORE SKILLS

  • Java Backend Development: Java 8?23 (10+ years, including Java 17+), Kotlin, Spring Boot 3.x, Spring MVC, Spring Data (JPA/Hibernate/JDBC); building and operating production services within large, established codebases
  • Microservices & Distributed Systems: Service decomposition, event-driven architecture, CQRS, Domain-Driven Design (DDD), high-concurrency systems, API Gateway patterns
  • Messaging & Streaming: Apache Kafka (event fan-out, high-throughput messaging), RabbitMQ, AWS SQS/SNS, ActiveMQ
  • REST & API Design: Designing and consuming REST APIs (OpenAPI/Swagger, contract-first, versioning, API lifecycle management), GraphQL, gRPC, SOAP
  • Engineering Best Practices: TDD, JUnit 5, Mockito, Testcontainers, SonarQube quality gates, code review standards, CI/CD (GitLab CI, Jenkins)
  • Cloud & Infrastructure: AWS (EKS, S3, RDS, Lambda, SQS, SNS, DynamoDB), Kubernetes, Docker, Terraform (IaC), GCP familiarity
  • Observability: Grafana, Prometheus, NewRelic, Datadog for production logging, metrics, and distributed monitoring
  • Independent Ownership: Track record of owning technical solutions end-to-end, from business problem to production, with minimal oversight, across distributed international teams
  • AI/ML Interest & Applied Experience: Hands-on use of AI coding assistants (Cursor, Claude Code, GitHub Copilot); built production NL-to-SQL and Sovereign-RAG systems with LLM integration, LangChain, and agentic workflows ? active interest in applying AI/ML to engineering and security-relevant problem spaces


KEY ACHIEVEMENTS

  • $24M Annual Savings: Scoped, designed, and built a custom high-concurrency API Gateway (Java, Spring Boot, REST) from scratch within a large existing codebase, replacing a costly third-party dependency end-to-end; recognised by the VP of Engineering
  • 70% Server Cost Reduction: Led decomposition of a large Java monolith into independently deployable microservices using CQRS, DDD, and event-driven architecture (Apache Kafka, Docker, Kubernetes), delivered incrementally with zero disruption to live systems
  • 40% Cloud Cost Reduction: Drove a Kubernetes right-sizing initiative on AWS EKS, translating infrastructure decisions into measurable business outcomes
  • Near-Instant Deployments: Designed an automated migration engine for a global airline cargo platform, cutting deployment time from 7 days to near-instant through clean API design and workflow orchestration


AI RESEARCH & INNOVATION (2025?2026)

  • Built a production NL-to-SQL pipeline (Java 23, LLM integration, DDD-structured domain layer) with clean architecture, TDD, and JDBC-backed relational persistence, from problem scoping to deployment and maintenance
  • Built a Sovereign-RAG system with agentic workflows (LangChain, LLM-as-a-Judge validation, Neo4j vector DB), event-driven design, secure-by-architecture, production-ready

Datenbanken

Oracle (PL/SQL)
PostgreSQL
isolation levels, sharding, performance tuning
MySQL
MongoDB
DynamoDB
Elasticsearch
Redis

Einsatzorte

Einsatzorte

Heidelberg (+75km)
Deutschland
nicht möglich

Projekte

Projekte

3 Jahre 11 Monate
2022-06 - 2026-04

Built and operated event-driven microservices

Lead/Senior Backend & Full-Stack Engineer
Lead/Senior Backend & Full-Stack Engineer
  • Owned backend domains end-to-end within T-Mobile's large, established T-Life codebase ? a high-scale, real-time consumer SaaS platform handling millions of concurrent requests ? working independently from problem framing through rollout
  • Built and operated event-driven microservices (Java, Spring Boot 3.x, Apache Kafka, RabbitMQ), communicating synchronously via REST and asynchronously via Kafka for high-throughput event fan-out between services
  • Designed and consumed REST/GraphQL/gRPC APIs encapsulating complex business logic for consumption across hundreds of internal services; enforced contract-first, OpenAPI-documented development and resilience patterns
  • Designed and scaled high-concurrency systems on PostgreSQL and MySQL: sharding strategy, transaction management, index tuning, and query optimisation under peak production load, maintaining sub-millisecond read paths
  • Drove $24M annual savings by scoping, designing, and implementing a custom high-concurrency API Gateway (Java/Spring Boot/REST), owned end-to-end from business problem to production; recognised by VP of Engineering
  • Provisioned and right-sized Kubernetes infrastructure (EKS/GKE-compatible) with Terraform on AWS; established Grafana/Prometheus/Datadog observability, achieving 40% cloud cost reduction
  • Practised and led TDD discipline across the team (JUnit 5, Mockito, Testcontainers) and enforced SonarQube quality gates and code-review standards in GitLab CI/CD; mentored junior engineers
  • Communicated clearly in English with distributed, cross-functional, international teams across multiple time zones; authored ADRs and architectural documentation
UST India Pvt Ltd (Client: T-Mobile USA)
1 Jahr 5 Monate
2021-02 - 2022-06

Led decomposition of a large Java monolith into independently deployable microservices

Senior Associate Consultant
Senior Associate Consultant
  • Led decomposition of a large Java monolith into independently deployable microservices for a complex automotive-diagnostics platform using CQRS, DDD, event-driven architecture (Apache Kafka), Docker, and Kubernetes, achieving a 70% server cost reduction with zero live-business disruption
  • Optimised Oracle and PostgreSQL databases: schema redesign, PL/SQL and JDBC-level tuning, transaction and locking analysis, sharding-aware indexing, and query analysis to support high-concurrency, high-throughput workloads
  • Implemented resilience patterns for unreliable third-party upstreams; automated ETL pipelines with Spring Batch; maintained high integration test coverage with Testcontainers in CI.
Infosys Pvt Ltd
2 Jahre
2019-03 - 2021-02

Designed and built a Java/Spring Boot automated migration engine

Software Engineer
Software Engineer
  • Designed and built a Java/Spring Boot automated migration engine for a global airline cargo management platform (REST APIs, SOAP integrations, Oracle DB, MongoDB) within a large legacy codebase; owned end-to-end from business scoping through implementation, testing, release, and maintenance
  • Delivered 200+ backend features in Scrum, working end-to-end across a complex multi-airline domain; contributed to 20% growth in global airline customer base through scalable, high-throughput system design
IBS Software
3 Jahre 6 Monate
2015-09 - 2019-02

Developed Java enterprise applications and REST/SOAP APIs

Software Engineer
Software Engineer
  • Developed Java enterprise applications and REST/SOAP APIs for logistics and e-commerce clients; designed relational (MySQL, Oracle) and NoSQL (MongoDB) data models for high-concurrency workloads
  • Introduced JUnit/Mockito TDD as a team-wide testing standard; diagnosed and resolved critical distributed system performance issues to maintain SLA compliance under production load
Pitsolutions

Aus- und Weiterbildung

Aus- und Weiterbildung

2011 ? 2015

B.Tech in Computer Science & Engineering ? Rajiv Gandhi Institute of Technology, Kerala, India

Kompetenzen

Kompetenzen

Top-Skills

Java 21 Spring Boot Microservices

Produkte / Standards / Erfahrungen / Methoden

PROFESSIONAL SUMMARY

Backend Software Engineer with 10+ years of production experience building and operating business-critical Java services (Java 8?23, including Java 17+) at high scale within large, established codebases. Strong track record designing and consuming REST APIs, building microservices and event-driven distributed systems with Apache Kafka and RabbitMQ, and owning technical solutions independently from problem framing through production rollout. Practises strong software engineering fundamentals ? TDD, code review, CI/CD ? and has set these standards across teams, not just followed them. Comfortable with Spring Boot, AWS, and Kubernetes in production, and experienced translating infrastructure and reliability work into measurable outcomes ($24M and 70% cost reductions). Clear, professional English communicator with hands-on interest in applying AI/ML to engineering workflows, including building production LLM-integrated systems.


CORE SKILLS

  • Java Backend Development: Java 8?23 (10+ years, including Java 17+), Kotlin, Spring Boot 3.x, Spring MVC, Spring Data (JPA/Hibernate/JDBC); building and operating production services within large, established codebases
  • Microservices & Distributed Systems: Service decomposition, event-driven architecture, CQRS, Domain-Driven Design (DDD), high-concurrency systems, API Gateway patterns
  • Messaging & Streaming: Apache Kafka (event fan-out, high-throughput messaging), RabbitMQ, AWS SQS/SNS, ActiveMQ
  • REST & API Design: Designing and consuming REST APIs (OpenAPI/Swagger, contract-first, versioning, API lifecycle management), GraphQL, gRPC, SOAP
  • Engineering Best Practices: TDD, JUnit 5, Mockito, Testcontainers, SonarQube quality gates, code review standards, CI/CD (GitLab CI, Jenkins)
  • Cloud & Infrastructure: AWS (EKS, S3, RDS, Lambda, SQS, SNS, DynamoDB), Kubernetes, Docker, Terraform (IaC), GCP familiarity
  • Observability: Grafana, Prometheus, NewRelic, Datadog for production logging, metrics, and distributed monitoring
  • Independent Ownership: Track record of owning technical solutions end-to-end, from business problem to production, with minimal oversight, across distributed international teams
  • AI/ML Interest & Applied Experience: Hands-on use of AI coding assistants (Cursor, Claude Code, GitHub Copilot); built production NL-to-SQL and Sovereign-RAG systems with LLM integration, LangChain, and agentic workflows ? active interest in applying AI/ML to engineering and security-relevant problem spaces


KEY ACHIEVEMENTS

  • $24M Annual Savings: Scoped, designed, and built a custom high-concurrency API Gateway (Java, Spring Boot, REST) from scratch within a large existing codebase, replacing a costly third-party dependency end-to-end; recognised by the VP of Engineering
  • 70% Server Cost Reduction: Led decomposition of a large Java monolith into independently deployable microservices using CQRS, DDD, and event-driven architecture (Apache Kafka, Docker, Kubernetes), delivered incrementally with zero disruption to live systems
  • 40% Cloud Cost Reduction: Drove a Kubernetes right-sizing initiative on AWS EKS, translating infrastructure decisions into measurable business outcomes
  • Near-Instant Deployments: Designed an automated migration engine for a global airline cargo platform, cutting deployment time from 7 days to near-instant through clean API design and workflow orchestration


AI RESEARCH & INNOVATION (2025?2026)

  • Built a production NL-to-SQL pipeline (Java 23, LLM integration, DDD-structured domain layer) with clean architecture, TDD, and JDBC-backed relational persistence, from problem scoping to deployment and maintenance
  • Built a Sovereign-RAG system with agentic workflows (LangChain, LLM-as-a-Judge validation, Neo4j vector DB), event-driven design, secure-by-architecture, production-ready

Datenbanken

Oracle (PL/SQL)
PostgreSQL
isolation levels, sharding, performance tuning
MySQL
MongoDB
DynamoDB
Elasticsearch
Redis

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