Serge Kalinin - Senior Data Scientist and MLOps Specialist

🚀 FRATCH GPT 2.0 - Find freelancers with a single prompt. With rate benchmark.

Recommended expert

Available

Munich, Germany

Check rate

Experience

Apr 2025 - Sep 2026

1 year 6 months

Cologne, Germany

Data Scientist & MLOps (Machine Learning Operations)

REWE Digital GmbH

It is like a startup within REWE, where we have to build a new forecasting system on Google Cloud Platform from the scratch. Although, officially my role is called MLOps, my actual tasks also include development of data processing pipelines (data engineering) and data scientists tasks such as feature engineering and model trainings.
GCP: Terraform (tofu), Vertex AI (Kubeflow), Cloud Run, IAM, Google Cloud Storage, BigQuery, Artifact Registry
Data engineering: Snowflake as the main data warehouse, Terraform, DBT for data model implementations
CI/CD: GitLab. We have built a CI/CD pipeline that automates deployments of new releases up to production environment
Development of feature store and data synchronization between environments
Data science: evaluation of different forecasting models, including CatBoost, Contextual Gamma and Random Forest; implementation of training pipelines using Kubeflow on Vertex AI; scaling and development of an event-driven interface using Kafka as a forecasting service; evaluation of MLFlow for model tracking and model registry
Implementation of REST API using KeyCloak OAuth2 and OpenID (JWT)
Monitoring: implementation of dashboards with Grafana, Prometheus, Mimir, Streamlit and Loki to monitor prediction metrics, GCP and Snowflake costs for pipelines, and system metrics
Development of Copilot Agent Skills

Jan 2025 - Apr 2025

4 months

United States

Senior Data Scientist

StarStruck

Consolidate visibility of companies or software products in marketplaces to compare footprints.
Develop data models and troubleshoot scraper scripts.
Assign development tasks to other developers.
Text analysis and implementation of recommendation system.
AWS: DynamoDB, Lambda, S3, EC2, IAM, EventBridge.
Scraping: Python, Selenium Chrome Webdriver.
Text analysis: Amazon Comprehend.
Recommendation system: XGBoost.
MLOps: MLFlow

Apr 2022 - Dec 2024

2 years 9 months

Karlsruhe, Germany

Senior Data Scientist

Atrvivia AG (via STI GmbH, Michael Page International)

Developed Data Integration Hub platform (DIH) for a Data Governance project, central architecture for sharing data between tenants, based on data product descriptions, data catalogs and services representing Data Mesh and Data Vault 2.0.
Workflow: inject data product description via REST API or Swagger UI; metadata written into Kafka topics; Kafka consumers create metadata in Datahub, tables in Trino, file structures on S3, policies, etc.
Implemented single sign-on in services based on JWT tokens.
Developed REST APIs and integration tools between SelfService, Trino, S3, Datahub, Great Expectations.
Performed data synchronization between S3 and Azure Blob Storage.
Developed ETL with PySpark on Azure Databricks and pipelines with pandas, PySpark, Airflow DAGs.
Built data quality validation services and monitoring systems.
Created accounting system based on CPU, storage and memory usage using star schema.
Developed complex data models (up to 5000 columns from several hundreds data sources).
Troubleshot and supported services and customers; delivered according to AGILE/SCRUM.
CI/CD: OpenShift (Kubernetes), Helm, Docker, Git, Tekton, ArgoCD, Terraform.
Data catalogs and lineage: Datahub, OpenLineage; Python, with integrations to Spark and Pandas.
SQL engines: Trino with Starburst Web UI, PostgreSQL, Hive, DB2, Delta Lake.
Data quality: Great Expectations, Talend.
Code quality: SonarQube.
REST API: Java, Swagger UI, Spring Boot.
Authentication: JWT, OAuth2, Single Sign-On; Apache Ranger; Prometheus and Grafana

Oct 2021 - Apr 2023

1 year 7 months

Hamburg, Germany

Senior Software Developer & Data Scientist (extern)

Otto GmbH & Co KG (via Soorce GmbH)

Designed and implemented data-driven microservices for search engine optimization using AWS services; ETL patterns: ingest data from REST API, SQS, DynamoDB; transform; upload to S3 or database.
Service I (MLOps): assessed OTTO pages by extracting keywords and matching with Google searches; migrated data transformation, model training/retraining, and deployment from GCP to AWS; designed workflows.
Used GitHub Actions for CI/CD and Terraform for cloud resource management.
Implemented model validations and testing with Python; model monitoring with Grafana.
Service S: handled millions of REST API calls per hour using AsyncIO; parsed nested JSON; stored results on S3.
Languages: Python, Java, TypeScript, Kotlin.
Monitoring: CloudWatch, Grafana, Tableau.
Databases: MongoDB, DynamoDB, PostgreSQL, Exasol.
Message processing: SNS, SQS.
Provisioning: Terraform, Pulumi, Serverless (Cloud Foundation).
Containers: Docker, ECR, ECS.
Unit tests: PyTest; delivery according to AGILE/SCRUM

Jul 2018 - Sep 2021

3 years 3 months

Cologne, Germany

Hybrid

Senior Big Data Consultant (extern)

REWE Systems GmbH (via STI GmbH)

Conceptualized and implemented hybrid environments on Google Cloud Platform.
Developed and optimized normalized data models and Spark ETL workflows using dbt.
Created data warehouse models on Hadoop using Data Vault 2.0.
Provisioned MapR and Spark (Databricks) environments on GCP with Terraform; set up real-time data replication from on-premise to GCP.
Integrated with REWE services (Active Directory, DNS, Instana).
Developed REST API for ML models using Flask.
Implemented persistent storage based on MapR for Kubernetes cluster.
Operated MapR clusters: upgrades, extensions, troubleshooting via Ansible and Jenkins.
Synchronized Kafka cluster with MapR streams using Kafka Connect.
Designed ETL pipelines, synchronization and integration of MapR with DB2 and Teradata.
Onboarded new internal customers; consulted management on Big Data topics; proposed security solutions and PoCs.
Developed market classification models; visualized data with Jupyter and Grafana; integrated with JIRA; delivered according to AGILE/SCRUM

Sep 2016 - May 2018

1 year 9 months

Munich, Germany

Senior Big Data Architect

Allianz Technology SE

Managed large-scale, multi-tenant, secure, highly available Hadoop infrastructure; provided architectural guidance, capacity planning, roadmaps for deployments.
Conducted pre-sales onboarding; worked with infrastructure, network, database, BI and data science teams.
Designed, implemented and maintained enterprise-level security for Hadoop (Kerberos, LDAP/AD, Sentry, encryption in motion and at rest).
Installed and configured multi-tenant Hadoop environments; managed updates, patches, upgrades; created run books for troubleshooting and maintenance.
Provided 3rd-level DevOps support; evaluated new tools and technologies.
Set up Microsoft R Open data science model training platform on Azure and on-premise using Docker and Terraform for fraud detection.
Developed Supply Chain Analytics GraphServer for HDFS graph queries.
Transformed internal processes to Agile/SCRUM.
Developed Kafka-based use cases: ClickStream (Java, Kafka, Flink, Cassandra), document classification (Java, Kafka, Spark Streaming, UIMA, Impala), graph database PoC (Java, Python, Kafka, Cassandra, Gremlin, KeyLines)

Jun 2014 - Jul 2016

2 years 2 months

Berlin, Germany

System Architect

The unbelievable Machine Company GmbH

Installation, configuration and operating of SAP HANA on Hortonworks Hadoop cluster

Sep 2012 - Jun 2014

1 year 10 months

Cologne, Germany

System Operations

Werkenntwen GmbH

Jan 2009 - Sep 2012

3 years 9 months

Wuppertal, Germany

Postdoc

Bergische Universität Wuppertal

Oct 2006 - Dec 2008

2 years 3 months

Aachen, Germany

Postdoc

Rheinisch-Westfälische Technische Hochschule Aachen

Industry experience

See where this freelancer has spent most of their professional time.

Experienced in Information Technology, Retail, Education, Media and Entertainment, and Insurance.

Information Technology

Retail

Education

Media and Entertainment

Insurance

Business area experience

See which departments and functions this freelancer has contributed to most.

Experienced in Information Technology, Research and Development, Product Development, Business Intelligence, Operations, and Quality Assurance.

Information Technology

Research and Development

Product Development

Business Intelligence

Operations

Quality Assurance

Skills

It: Object Oriented Programming, Databases, Administration, Distributed Computing, High Performance Computing, High Availability
Profound Knowledge Of Public Clouds: Aws, Microsoft Azure, Google Cloud Platform
Infrastructure As Code: Terraform, Ansible, Puppet
Expert In Hadoop Stacks: Hortonworks, Mapr, Cloudera, Spark, Kafka, Flume, Storm, Oozie, Sentry, Ranger, Knox, Hbase, Sqoop, Yarn, Mesos, Impala, Hive, Zookeeper, Key Trustee
Expert In Network Devices: Loadbalancer (F5, A10), Switches (Arista, Juniper, Force10), Firewalls (Juniper, Fortigate, Palo Alto), Routers (Brocade)
Programming Languages: Python, Java, Sql, Scala, C++, Php, Vba, R, Ruby
Expert In Application Level Security Systems: Web Application Firewall, Xml-Gateway, Haproxy
Expert In Databases: Mysql, Postgresql, Objectivity, Oracle, Microsoft Sql Server
Expert In Linux. Very Good Knowledge Of Microsoft Windows
Expert In Mass-Storage Systems: Emc Isilon, Scality, Lustre/Sfs, Pnfs, Hadoop, Dcache, Netapp
Expert In Virtualization And Containerization: Kvm, Xen, Vmware, Virtualbox, Vagrant, Docker, Cloudfoundry, Kubernetes, Citrix
Scms: Git, Svn, Nexus, Cvs
Expert In Monitoring: Grafana, Prometheus, Nagios, Cacti, Ganglia, Munin, Lemon, Streamlit
Expert In Statistics: Monte Carlo, Statistical Tests, Parameter Estimation, Error Estimation, Classification, Prediction, Unfolding, Fitting
Expert In Technical Analyses
Expert In Multi-Variate Methods: Neural Networks, Support Vector Machines, Genetic Algorithms, Gradient Boosting
Good Knowledge Of Security Standards Such As Pci Dss
Ldap Authentication Systems: Activedirectory, Openldap, Apacheds
Authentication Systems: Oauth2, Single Sign-On

Languages

Russian

Native

German

Advanced

English

Advanced

French

Advanced

Education

Jan 2001 - Sep 2006

Université catholique de Louvain-la-Neuve

PhD Student · Ottignies-Louvain-la-Neuve, Belgium

Sep 1998 - Jun 2000

Moscow Institute of Physics and Technology

M.S., High energy physics · High energy physics · Dolgoprudny, Russian Federation

Sep 1994 - Jun 1998

Moscow Institute of Physics and Technology

B.S., High energy physics · High energy physics · Dolgoprudny, Russian Federation

Certifications & licenses

Statistics

Experience

Total positions 10

Experience in Information Technology 13 y

Avg length 2 y

Longest experience 3 y 8 m

Global experience

Countries worked in 2 (Germany, United States)

Primary country Germany

Expertise

Recent roles Data Scientist & MLOps (Machine Learning Operations), Senior Data Scientist, Senior Software Developer & Data Scientist (extern)

Main industries Information Technology, Retail, Education

Main business areas Information Technology, Research and Development, Product Development

Qualifications

Highest degree Master

Certifications earned 1

Profile

Member since

December 2024

Last update

October 2026

Need a freelancer? Find your match in seconds.

Try FRATCH GPT

Frequently asked questions

Have questions? Find more information here.

Serge is based in Munich, Germany and prefers 100% remote projects.

Serge speaks the following languages: Russian (Native), German (Advanced), English (Advanced), French (Advanced).

Serge has at least 20 years of experience. During this time, Serge has worked in at least 8 different roles and for 10 different companies. The average length of individual experience is 2 years. Note that Serge may not have shared all experience and actually has more experience.

Based on recent experience, Serge would be well-suited for roles such as: Data Scientist & MLOps (Machine Learning Operations), Senior Data Scientist, Senior Software Developer & Data Scientist (extern).

Serge's most recent position is Data Scientist & MLOps (Machine Learning Operations) at REWE Digital GmbH.

In recent years, Serge has worked for REWE Digital GmbH, StarStruck, Atrvivia AG (via STI GmbH, Michael Page International), and Otto GmbH & Co KG (via Soorce GmbH).

Serge is most experienced in industries like Information Technology, Retail, and Education. Serge also has some experience in Media and Entertainment and Insurance.

Serge is most experienced in business areas like Information Technology, Research and Development, and Product Development. Serge also has some experience in Business Intelligence, Operations, and Quality Assurance.

Serge has recently worked in industries like Information Technology and Retail.

Serge has recently worked in business areas like Information Technology, Product Development, and Quality Assurance.

Serge holds a Master in High energy physics from Moscow Institute of Physics and Technology and a Bachelor in High energy physics from Moscow Institute of Physics and Technology.

Serge has 1 certificate: AWS Certified Data Engineer - Associate.

Serge is immediately available full-time for suitable projects.

Daily rate distribution

0% 25% 50% 75% 100%

<€960 €960-1120 €1120-1280 €1440+

The rates shown represent the typical market range for freelancers in this position based on recent contracts on our platform.

Average rates for similar positions

Rates are based on recent contracts and do not include FRATCH margin.

1000

750

500

250

Daily rate avg. 923 €

The average daily rate is the mean of all daily rates from recent contracts of comparable freelancers on our platform.

1000

750

500

250

Median rate 900 €

The median daily rate is the middle value of all daily rates — half of comparable freelancers charge less, half charge more. Unlike the average, it is barely affected by outliers.

Calculated based on our freelancers’ daily rates as of 18 Oct 2026. Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.