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I'm Cosmin-Constantin Ungureanu, a Java backend developer with 4+ years building production systems for banks and insurers. I focus on Spring Boot microservices, reactive HTTP clients (WebClient / Project Reactor), REST API design, and clean, well-tested code on cloud infrastructure (AWS, GCP). I also design and ship agentic AI tooling (MCP servers, Claude Code integration) for production codebases, and I'm available for remote backend missions.…I'm Cosmin-Constantin Ungureanu, a Java backend developer with 4+ years building production systems for banks and insurers. I focus on Spring Boot microservices, reactive HTTP clients (WebClient / Project Reactor), REST API design, and clean, well-tested code on cloud infrastructure (AWS, GCP). I also design and ship agentic AI tooling (MCP servers, Claude Code integration) for production codebases, and I'm available for remote backend missions.

Cosmin-Constantin Ungureanu

Back-End Developer, Web Developer, App Developer, +1

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I'm Cosmin-Constantin Ungureanu, a Java backend developer with 4+ years building production systems for banks and insurers. I focus on Spring Boot microservices, reactive HTTP clients (WebClient / Project Reactor), REST API design, and clean, well-tested code on cloud infrastructure (AWS, GCP). I also design and ship agentic AI tooling (MCP servers, Claude Code integration) for production codebases, and I'm available for remote backend missions.…I'm Cosmin-Constantin Ungureanu, a Java backend developer with 4+ years building production systems for banks and insurers. I focus on Spring Boot microservices, reactive HTTP clients (WebClient / Project Reactor), REST API design, and clean, well-tested code on cloud infrastructure (AWS, GCP). I also design and ship agentic AI tooling (MCP servers, Claude Code integration) for production codebases, and I'm available for remote backend missions.

Available to hire

I’m Cosmin-Constantin Ungureanu, a Java backend developer with 4+ years building production systems for banks and insurers. I focus on Spring Boot microservices, reactive HTTP clients (WebClient / Project Reactor), REST API design, and clean, well-tested code on cloud infrastructure (AWS, GCP).
I also design and ship agentic AI tooling (MCP servers, Claude Code integration) for production codebases, and I’m available for remote backend missions.

Skills

Experience Level

Expert

Expert

Expert

Expert

Language

Romanian, Moldavian, Moldovan

Fluent

English

Fluent

French

Advanced

Work Experience

Java Backend Developer at Swiss Life France

September 1, 2024 - Present

Backend developer on Swiss Life's claims modernization programme. Designed a multi-module Maven architecture and built a reactive HTTP client with configurable timeouts and exponential-backoff; implemented a HATEOAS pipeline to navigate Sinapps; applied the Strategy pattern for 36 event types and 14 commands; integrated multi-tenant OAuth2 and COBOL mainframe bridging; authored 40+ MapStruct mappers; established tests and addressed vulnerabilities.

Java Developer at Deutsche Bank Global Technologies

September 1, 2022 - August 31, 2024

Developed and maintained external REST APIs for payments; built microservices on Google Cloud Platform with Spring Boot, PostgreSQL, Hibernate, and Flyway; designed API contracts with Swagger Editor; achieved 90%+ test coverage; integrated Sonar, Veracode, and Spotless; used Postman and JUnit for API tests.

Forensic Specialist at General Police Directorate, Bucharest

January 1, 2016 - December 31, 2022

Forensic firearm and trace identification across crime scenes; developed analytical rigor and the ability to communicate complex findings clearly to non-technical stakeholders.