Java/Spring Boot Backend Developer & AI/ML Engineer ? Generative AI, LLM Integration, RAG, Spring AI, Machine Learning, Python, MLOps
Aktualisiert am 21.08.2026
Profil
Freiberufler / Selbstständiger
Remote-Arbeit
Verfügbar ab: 01.09.2026
Verfügbar zu: 100%
davon vor Ort: 100%
Java
Spring Boot
Generative AI
Spring AI
RAG
LLM Integration
Python
Machine Learning
Deep Learning
MLOps
LangChain
Vector Database
REST API
Microservices
Hibernate/JPA
PostgreSQL
Docker
Kubernetes
Git
Maven
CI/CD
SQL
JUnit
English
C1
German
C1
Persian
native
Turkish
basic

Einsatzorte

Einsatzorte

Cologne (+50km) Brühl, Rheinland (+100km) Bonn (+50km) Düsseldorf (+50km)
Deutschland, Schweiz, Österreich
möglich

Projekte

Projekte

8 months
2026-01 - 2026-08

CryptoCopilot ? Applied AI Engineering / RAG in Production

Java / Spring Boot Spring AI pgvector ...
  • Production-grade RAG pipeline (indexer ? recency-aware retriever ? grounded generator) on Spring AI and pgvector (HNSW, cosine distance); 0.90 Recall@8 and a 100 % citation rate by design. 
  • Deterministic grounding and refusal logic (no answer without a verifiable source) plus a numeric hallucination guard that checks every generated figure against deterministic inputs. 
  • Polyglot multi-container architecture (Java/Spring backend, Python ML service, React frontend) with strict single-writer table ownership over a shared PostgreSQL database. 
  • LLM provider swappable at runtime (local Ollama ? OpenAI) ? no code changes, no re-indexing; enables GDPR-compliant on-premises operation. 
Java / Spring Boot Spring AI pgvector Python React
8 months
2026-01 - 2026-08

Sign Language Recognition ? Deep Learning / Computer Vision

TensorFlow / Keras EfficientNetV2S Transfer Learning
  • Deep learning classifier at 99.70 % accuracy: group-aware data split (no leakage), two-phase training (feature extraction ? fine-tuning) and domain-specific augmentation. 
TensorFlow / Keras EfficientNetV2S Transfer Learning
1 year
2025-01 - 2025-12

Mushroom Classification ? Machine Learning under a Safety Constraint

Scikit-learn Random Forest XGBoost ...
  • Classification pipeline with zero false negatives on toxic species ? thresholds and metrics chosen against the real cost of error, not against accuracy. 
Scikit-learn Random Forest XGBoost Pipeline
2 years 9 months
2022-10 - 2025-06

Built and operated backend services

Backend Engineer (Java / Spring Boot) Java Spring Boot REST API ...
Backend Engineer (Java / Spring Boot)
  • Built and operated backend services for WDR?s Sophora CMS with Java and Spring Boot ? delivering content to millions of users through the ARD-Mediathek. 
  • Optimised search relevance and ranking with Apache Solr ? the same retrieval logic that now determines the quality of RAG systems. 
  • Designed REST APIs for content exchange; increased system resilience with Resilience4j. 
Sophora CMS Apache Solr PostgreSQL Jenkins Docker Git Jira
Java Spring Boot REST API Apache Solr Resilience4j Microservices PostgreSQL Hibernate/JPA Docker Jenkins CI/CD Git JUnit Scrum
WDR (Westdeutscher Rundfunk) via ALTEN GmbH
Cologne, Germany
3 years 3 months
2019-01 - 2022-03

Developed cash and asset management modules

Software Engineer (Backend)
Software Engineer (Backend)
  • Developed cash and asset management modules; led the migration from a monolith to microservices. 
  • Optimised performance-critical SQL queries over high data volumes. 
Navaco, Tehran, Iran
1 year 5 months
2017-08 - 2018-12

Built a statistics and reporting module

Software Engineer (Full-Stack)
Software Engineer (Full-Stack)
  • Built a statistics and reporting module with Spring Boot and React.js for a stock brokerage platform. 
DPI Co, Tehran, Iran
1 year 7 months
2016-01 - 2017-07

Developed an automated smart irrigation system

IoT Engineer (R&D)
IoT Engineer (R&D)
  • Developed an automated smart irrigation system with forecast-based control (weather data); reduced water consumption by 70 %. 
IKIU, Qazvin, Iran

Aus- und Weiterbildung

Aus- und Weiterbildung

1 year 2 months
2025-07 - 2026-08

Professional Training "Data Science and AI"

Graduation Certificate, Data Science and AI, WBS Coding School, Germany
Graduation Certificate, Data Science and AI
WBS Coding School, Germany
  • Machine Learning and Deep Learning: Scikit-learn, TensorFlow/Keras, XGBoost, CNNs, Transfer Learning, Computer Vision
  • Building RAG applications with Large Language Models
  • Data analysis and engineering with Python, Pandas and SQL; data warehouses and database management
  • Cloud data engineering on Microsoft Azure; DevOps automation, CI/CD pipelines and containerisation with Docker
  • Time series forecasting, A/B testing and statistical analysis
  • Data visualisation and dashboards with Tableau and Looker Studio
  • Includes a two-month practical phase (internship) at essentis GmbH
5 years 1 month
2010-09 - 2015-09

Academic Studies in Computer Engineering (Software Engineering)

Bachelor of Science (B.Sc.) in Computer Engineering, Qazvin Islamic Azad University (QIAU), Qazvin
Bachelor of Science (B.Sc.) in Computer Engineering
Qazvin Islamic Azad University (QIAU), Qazvin
  • Four-year full-time academic degree programme in Computer Engineering, specialisation Software Engineering.
  • Software engineering, algorithms and data structures, object-oriented programming and compiler design.
  • Database systems, computer networks, operating systems and computer architecture.
  • Embedded and microcontroller systems; engineering mathematics and discrete structures.
  • Recognised as equivalent to a German Bachelor's degree (Zeugnisbewertung, ZAB / Kultusministerkonferenz).

Position

Position

Senior Backend Engineer and AI/ML Engineer with 9+ years of experience in production Java and Spring Boot systems, most recently backend services for an enterprise CMS delivering content to millions of users.

I bring generative AI into existing enterprise systems as a production feature rather than a prototype: RAG pipelines, LLM integration, AI agents and vector search ? secure, tested, maintainable and GDPR-compliant, including on-premises operation.

Areas of application:
  • Design and implementation of RAG pipelines and LLM integration (Spring AI, LangChain, pgvector, embeddings, vector search)
  • Senior backend development: architecture, REST API design, microservices, migrations, performance optimisation, code reviews
  • Machine learning and deep learning: model development, evaluation and deployment (Scikit-learn, TensorFlow/Keras, XGBoost)
  • MLOps and DevOps: Docker, Kubernetes, CI/CD, MLflow, Microsoft Azure
  • Technical consulting on introducing generative AI into existing product landscapes

Working remotely or on site in the Cologne / Bonn / Düsseldorf area. Project languages: English and German.

Kompetenzen

Kompetenzen

Top-Skills

Java Spring Boot Generative AI Spring AI RAG LLM Integration Python Machine Learning Deep Learning MLOps LangChain Vector Database REST API Microservices Hibernate/JPA PostgreSQL Docker Kubernetes Git Maven CI/CD SQL JUnit

Schwerpunkte

Java
Experte
Spring Boot
Experte
Generative AI
Experte
LLM
Experte
RAG
Experte
Spring AI
Experte
Machine Learning
Experte
Deep Learning
Experte
MLOps
Experte
Microservices
Experte
REST API
Experte
Backend Development
Experte
9+ years of production Java/Spring Boot backend development, combined with generative AI and machine learning brought into existing enterprise systems as production features.

Aufgabenbereiche

Software Architecture
Experte
Backend Development
Experte
API Design
Experte
Technical Consulting
Experte
Performance Optimisation
Experte
Code Review
Experte
Migration
Experte
Requirements Analysis
Experte
Architecture and implementation of backend services and AI integrations; API design, migrations, performance optimisation, code reviews and technical consulting.

Produkte / Standards / Erfahrungen / Methoden

Spring AI
LangChain
Ollama
OpenAI API
pgvector
Apache Solr
Resilience4j
Hibernate
JPA
Maven
JUnit
Docker
Kubernetes
Jenkins
MLflow
Airflow
TensorFlow
Keras
Scikit-learn
with Certificate
XGBoost
Microsoft Azure
with Certificate (Azure DP-900)
Git
Scrum
Test-Driven Development
Clean Code
CI/CD
GDPR

PROFILE

  • AI Engineer and Machine Learning Engineer with 9+ years of software engineering experience ? mostly in production Java/Spring Boot systems reaching millions of users through the ARD-Mediathek, Germany?s public broadcasting platform. 
  • Builds AI as a production feature inside existing enterprise systems rather than as a prototype: RAG pipelines, LLM integration, AI agents and ML models ? secure, tested, maintainable and GDPR-compliant. 
  • Combines two profiles that rarely meet in one person: the model side (machine learning, deep learning, MLOps) and the engineering side that reliably takes models into production ? which is exactly where most AI projects fail. 


CORE SKILLS

  • AI Engineering & LLM: LLMs, RAG pipelines, Spring AI, LangChain, Prompt Engineering, AI Agents, MCP, Embeddings, Vector Search (pgvector, HNSW), Ollama, OpenAI API, NLP 
  • Machine Learning & Deep Learning: Scikit-learn, TensorFlow / Keras, XGBoost, Random Forest, CNNs, Transfer Learning (EfficientNetV2), Computer Vision, Feature Engineering, Model Evaluation 
  • MLOps, Cloud & DevOps: MLflow, Airflow, Docker, Kubernetes, CI/CD (Jenkins), Git, Microsoft Azure (DP-900), BigQuery 
  • Software Engineering & Architecture: Java, Spring Boot, REST APIs, Microservices, Resilience4j, Apache Solr, PostgreSQL, MySQL, MongoDB, React.js 
  • Data & Analytics: Python, Pandas, NumPy, SQL, Tableau, Looker Studio, Plotly 


Others

Vector search with pgvector (HNSW, cosine distance), retrieval tuning with Apache Solr, containerised delivery with Docker/Kubernetes and CI/CD, agile delivery (Scrum) with code reviews and TDD.

Betriebssysteme

Linux
Experte
Windows
Experte
macOS
Experte
Linux for development, containers and deployment; Windows and macOS as working environments.

Programmiersprachen

Java
Experte
Python
Experte
SQL
Experte
JavaScript
Experte
TypeScript
Experte
HTML
Experte
CSS
Experte
Java: 9+ years, primary language. Python: applied machine learning, data processing and ML services. SQL: query design and performance tuning on large data volumes. JavaScript/TypeScript: React frontends.

Datenbanken

PostgreSQL
Experte
MySQL
Experte
MongoDB
Experte
pgvector
Experte
BigQuery
Experte
PostgreSQL as primary database, including pgvector for embedding storage and vector search. Query optimisation over high data volumes; schema design and migrations.

Datenkommunikation

REST
HTTP
HTTPS
JSON
WebSocket
TCP/IP
OAuth 2.0
gRPC
Design and implementation of REST APIs for system-to-system content exchange; token-based authentication (OAuth 2.0) and resilient service-to-service communication.

Branchen

Branchen

Industry experience:

Media and Broadcasting ? backend services for an enterprise CMS at WDR (Westdeutscher Rundfunk) via ALTEN GmbH; content delivery at scale through the ARD-Mediathek, search relevance and ranking.

Banking and Financial Services ? cash and asset management modules; statistics and reporting for a stock brokerage platform; performance-critical SQL over high data volumes.

Engineering Services and IT Consulting ? project work as a consultant at ALTEN GmbH, both in-house and on client site.

Public Sector ? project delivery in a public broadcasting environment, with corresponding requirements for data protection, documentation and system stability.

Open to projects across industries. My core competence ? Java/Spring Boot backend engineering and production-grade generative AI integration ? transfers directly to insurance, manufacturing, e-commerce, healthcare and the public sector, particularly where existing enterprise systems need AI features under GDPR constraints, including on-premises operation.

Einsatzorte

Einsatzorte

Cologne (+50km) Brühl, Rheinland (+100km) Bonn (+50km) Düsseldorf (+50km)
Deutschland, Schweiz, Österreich
möglich

Projekte

Projekte

8 months
2026-01 - 2026-08

CryptoCopilot ? Applied AI Engineering / RAG in Production

Java / Spring Boot Spring AI pgvector ...
  • Production-grade RAG pipeline (indexer ? recency-aware retriever ? grounded generator) on Spring AI and pgvector (HNSW, cosine distance); 0.90 Recall@8 and a 100 % citation rate by design. 
  • Deterministic grounding and refusal logic (no answer without a verifiable source) plus a numeric hallucination guard that checks every generated figure against deterministic inputs. 
  • Polyglot multi-container architecture (Java/Spring backend, Python ML service, React frontend) with strict single-writer table ownership over a shared PostgreSQL database. 
  • LLM provider swappable at runtime (local Ollama ? OpenAI) ? no code changes, no re-indexing; enables GDPR-compliant on-premises operation. 
Java / Spring Boot Spring AI pgvector Python React
8 months
2026-01 - 2026-08

Sign Language Recognition ? Deep Learning / Computer Vision

TensorFlow / Keras EfficientNetV2S Transfer Learning
  • Deep learning classifier at 99.70 % accuracy: group-aware data split (no leakage), two-phase training (feature extraction ? fine-tuning) and domain-specific augmentation. 
TensorFlow / Keras EfficientNetV2S Transfer Learning
1 year
2025-01 - 2025-12

Mushroom Classification ? Machine Learning under a Safety Constraint

Scikit-learn Random Forest XGBoost ...
  • Classification pipeline with zero false negatives on toxic species ? thresholds and metrics chosen against the real cost of error, not against accuracy. 
Scikit-learn Random Forest XGBoost Pipeline
2 years 9 months
2022-10 - 2025-06

Built and operated backend services

Backend Engineer (Java / Spring Boot) Java Spring Boot REST API ...
Backend Engineer (Java / Spring Boot)
  • Built and operated backend services for WDR?s Sophora CMS with Java and Spring Boot ? delivering content to millions of users through the ARD-Mediathek. 
  • Optimised search relevance and ranking with Apache Solr ? the same retrieval logic that now determines the quality of RAG systems. 
  • Designed REST APIs for content exchange; increased system resilience with Resilience4j. 
Sophora CMS Apache Solr PostgreSQL Jenkins Docker Git Jira
Java Spring Boot REST API Apache Solr Resilience4j Microservices PostgreSQL Hibernate/JPA Docker Jenkins CI/CD Git JUnit Scrum
WDR (Westdeutscher Rundfunk) via ALTEN GmbH
Cologne, Germany
3 years 3 months
2019-01 - 2022-03

Developed cash and asset management modules

Software Engineer (Backend)
Software Engineer (Backend)
  • Developed cash and asset management modules; led the migration from a monolith to microservices. 
  • Optimised performance-critical SQL queries over high data volumes. 
Navaco, Tehran, Iran
1 year 5 months
2017-08 - 2018-12

Built a statistics and reporting module

Software Engineer (Full-Stack)
Software Engineer (Full-Stack)
  • Built a statistics and reporting module with Spring Boot and React.js for a stock brokerage platform. 
DPI Co, Tehran, Iran
1 year 7 months
2016-01 - 2017-07

Developed an automated smart irrigation system

IoT Engineer (R&D)
IoT Engineer (R&D)
  • Developed an automated smart irrigation system with forecast-based control (weather data); reduced water consumption by 70 %. 
IKIU, Qazvin, Iran

Aus- und Weiterbildung

Aus- und Weiterbildung

1 year 2 months
2025-07 - 2026-08

Professional Training "Data Science and AI"

Graduation Certificate, Data Science and AI, WBS Coding School, Germany
Graduation Certificate, Data Science and AI
WBS Coding School, Germany
  • Machine Learning and Deep Learning: Scikit-learn, TensorFlow/Keras, XGBoost, CNNs, Transfer Learning, Computer Vision
  • Building RAG applications with Large Language Models
  • Data analysis and engineering with Python, Pandas and SQL; data warehouses and database management
  • Cloud data engineering on Microsoft Azure; DevOps automation, CI/CD pipelines and containerisation with Docker
  • Time series forecasting, A/B testing and statistical analysis
  • Data visualisation and dashboards with Tableau and Looker Studio
  • Includes a two-month practical phase (internship) at essentis GmbH
5 years 1 month
2010-09 - 2015-09

Academic Studies in Computer Engineering (Software Engineering)

Bachelor of Science (B.Sc.) in Computer Engineering, Qazvin Islamic Azad University (QIAU), Qazvin
Bachelor of Science (B.Sc.) in Computer Engineering
Qazvin Islamic Azad University (QIAU), Qazvin
  • Four-year full-time academic degree programme in Computer Engineering, specialisation Software Engineering.
  • Software engineering, algorithms and data structures, object-oriented programming and compiler design.
  • Database systems, computer networks, operating systems and computer architecture.
  • Embedded and microcontroller systems; engineering mathematics and discrete structures.
  • Recognised as equivalent to a German Bachelor's degree (Zeugnisbewertung, ZAB / Kultusministerkonferenz).

Position

Position

Senior Backend Engineer and AI/ML Engineer with 9+ years of experience in production Java and Spring Boot systems, most recently backend services for an enterprise CMS delivering content to millions of users.

I bring generative AI into existing enterprise systems as a production feature rather than a prototype: RAG pipelines, LLM integration, AI agents and vector search ? secure, tested, maintainable and GDPR-compliant, including on-premises operation.

Areas of application:
  • Design and implementation of RAG pipelines and LLM integration (Spring AI, LangChain, pgvector, embeddings, vector search)
  • Senior backend development: architecture, REST API design, microservices, migrations, performance optimisation, code reviews
  • Machine learning and deep learning: model development, evaluation and deployment (Scikit-learn, TensorFlow/Keras, XGBoost)
  • MLOps and DevOps: Docker, Kubernetes, CI/CD, MLflow, Microsoft Azure
  • Technical consulting on introducing generative AI into existing product landscapes

Working remotely or on site in the Cologne / Bonn / Düsseldorf area. Project languages: English and German.

Kompetenzen

Kompetenzen

Top-Skills

Java Spring Boot Generative AI Spring AI RAG LLM Integration Python Machine Learning Deep Learning MLOps LangChain Vector Database REST API Microservices Hibernate/JPA PostgreSQL Docker Kubernetes Git Maven CI/CD SQL JUnit

Schwerpunkte

Java
Experte
Spring Boot
Experte
Generative AI
Experte
LLM
Experte
RAG
Experte
Spring AI
Experte
Machine Learning
Experte
Deep Learning
Experte
MLOps
Experte
Microservices
Experte
REST API
Experte
Backend Development
Experte
9+ years of production Java/Spring Boot backend development, combined with generative AI and machine learning brought into existing enterprise systems as production features.

Aufgabenbereiche

Software Architecture
Experte
Backend Development
Experte
API Design
Experte
Technical Consulting
Experte
Performance Optimisation
Experte
Code Review
Experte
Migration
Experte
Requirements Analysis
Experte
Architecture and implementation of backend services and AI integrations; API design, migrations, performance optimisation, code reviews and technical consulting.

Produkte / Standards / Erfahrungen / Methoden

Spring AI
LangChain
Ollama
OpenAI API
pgvector
Apache Solr
Resilience4j
Hibernate
JPA
Maven
JUnit
Docker
Kubernetes
Jenkins
MLflow
Airflow
TensorFlow
Keras
Scikit-learn
with Certificate
XGBoost
Microsoft Azure
with Certificate (Azure DP-900)
Git
Scrum
Test-Driven Development
Clean Code
CI/CD
GDPR

PROFILE

  • AI Engineer and Machine Learning Engineer with 9+ years of software engineering experience ? mostly in production Java/Spring Boot systems reaching millions of users through the ARD-Mediathek, Germany?s public broadcasting platform. 
  • Builds AI as a production feature inside existing enterprise systems rather than as a prototype: RAG pipelines, LLM integration, AI agents and ML models ? secure, tested, maintainable and GDPR-compliant. 
  • Combines two profiles that rarely meet in one person: the model side (machine learning, deep learning, MLOps) and the engineering side that reliably takes models into production ? which is exactly where most AI projects fail. 


CORE SKILLS

  • AI Engineering & LLM: LLMs, RAG pipelines, Spring AI, LangChain, Prompt Engineering, AI Agents, MCP, Embeddings, Vector Search (pgvector, HNSW), Ollama, OpenAI API, NLP 
  • Machine Learning & Deep Learning: Scikit-learn, TensorFlow / Keras, XGBoost, Random Forest, CNNs, Transfer Learning (EfficientNetV2), Computer Vision, Feature Engineering, Model Evaluation 
  • MLOps, Cloud & DevOps: MLflow, Airflow, Docker, Kubernetes, CI/CD (Jenkins), Git, Microsoft Azure (DP-900), BigQuery 
  • Software Engineering & Architecture: Java, Spring Boot, REST APIs, Microservices, Resilience4j, Apache Solr, PostgreSQL, MySQL, MongoDB, React.js 
  • Data & Analytics: Python, Pandas, NumPy, SQL, Tableau, Looker Studio, Plotly 


Others

Vector search with pgvector (HNSW, cosine distance), retrieval tuning with Apache Solr, containerised delivery with Docker/Kubernetes and CI/CD, agile delivery (Scrum) with code reviews and TDD.

Betriebssysteme

Linux
Experte
Windows
Experte
macOS
Experte
Linux for development, containers and deployment; Windows and macOS as working environments.

Programmiersprachen

Java
Experte
Python
Experte
SQL
Experte
JavaScript
Experte
TypeScript
Experte
HTML
Experte
CSS
Experte
Java: 9+ years, primary language. Python: applied machine learning, data processing and ML services. SQL: query design and performance tuning on large data volumes. JavaScript/TypeScript: React frontends.

Datenbanken

PostgreSQL
Experte
MySQL
Experte
MongoDB
Experte
pgvector
Experte
BigQuery
Experte
PostgreSQL as primary database, including pgvector for embedding storage and vector search. Query optimisation over high data volumes; schema design and migrations.

Datenkommunikation

REST
HTTP
HTTPS
JSON
WebSocket
TCP/IP
OAuth 2.0
gRPC
Design and implementation of REST APIs for system-to-system content exchange; token-based authentication (OAuth 2.0) and resilient service-to-service communication.

Branchen

Branchen

Industry experience:

Media and Broadcasting ? backend services for an enterprise CMS at WDR (Westdeutscher Rundfunk) via ALTEN GmbH; content delivery at scale through the ARD-Mediathek, search relevance and ranking.

Banking and Financial Services ? cash and asset management modules; statistics and reporting for a stock brokerage platform; performance-critical SQL over high data volumes.

Engineering Services and IT Consulting ? project work as a consultant at ALTEN GmbH, both in-house and on client site.

Public Sector ? project delivery in a public broadcasting environment, with corresponding requirements for data protection, documentation and system stability.

Open to projects across industries. My core competence ? Java/Spring Boot backend engineering and production-grade generative AI integration ? transfers directly to insurance, manufacturing, e-commerce, healthcare and the public sector, particularly where existing enterprise systems need AI features under GDPR constraints, including on-premises operation.

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