Senior Java Backend Developer

Cagdas builds the systems
the business runs on.

Over ten years engineering enterprise backends across insurance, reinsurance, fintech and SaaS — with a specialty in deep JDK internals, concurrency, and database performance.

● Available — fully remote Germany · EU timezones DE C1 · EN fluent · TR native
// how a request moves through a system I build
Client
REST
API
Spring Boot
Service
domain logic
JPA
Hibernate
DB
Postgres / Oracle
01 About

Depth over breadth, by design.

I'm a senior Java engineer who goes deep where it matters. As sole developer of a core financial and bookkeeping module in a live enterprise platform, I owned everything from domain modelling to concurrency and transactional correctness — hardening its ledger to eliminate a class of data-integrity defects.

My foundation is deliberate: JDK and JVM internals, SQL and database performance, and the failure modes real systems hit under load — N+1 queries, lock contention, isolation anomalies, and race conditions. I care about code that is correct at 3 a.m., not just code that demos well.

I'm now looking for a fully remote senior role where that depth is valued.

02 Experience

Enterprise systems, end to end.

Senior Java Developer / Product Owner · MID Technologien GmbH
2024 – present

Sole developer of MIDbridge's core Booking Manager module (~90% of the codebase) — the product's central financial component, with direct CTO endorsement. Backend services, booking logic, and Chargebee / Stripe / DATEV integrations.

Freelance Full-Stack Java Developer (remote) · Questax Systems GmbH
2023 – 2024

Built an enterprise support platform fully remotely — Spring Boot backend, Angular / TypeScript frontend, MariaDB and Docker-based deployments.

Associate Systems Consultant (Java Backend) · General Reinsurance AG
2020 – 2023

Enterprise backend applications for the reinsurance business — REST services, batch-processing and automation tools, Oracle and IBM DB2, in international cross-site agile teams.

Java Developer · HDI Systeme AG
2019 – 2020

Java RCP plugins for enterprise insurance software.

ABS / Java RCP Developer · Allianz Technology
2014 – 2018

Java RCP enterprise applications (ABS); built UI / binder code generators and nightly unit-test report automation to speed up development.

03 Stack & Credentials

What I work with.

Core

Java 8–11Spring / Spring BootJPA / HibernateSQLPostgreSQLOracleREST APIsConcurrency

Also using

AWSDockerGitMavenJUnitJenkinsCI/CD

Certifications

AWS Solutions Architect AssociateOracle OCP — Java SE 8Oracle OCA — Java SE 8Azure AZ-900Azure DP-900

Education & languages

M.Sc. Technical Computer Science — TU BerlinB.Sc. Electronics Eng. — TOBB UniversityTurkish (native)German (C1)English (fluent)Russian (A2)Spanish (A2)
04 Contact

Let's talk.

Open to fully remote senior Java roles. The fastest way to reach me is email — I reply within a day.