You're seeing this page as if you were . The main menu is still yours, though. Exit from immersion
Lorena GongangLG

Lorena Gongang

Data Engineer

€600/day
Paris, FR
3-7 years

Average response time: 1 hour

Freelancer profile translated to English.
Back to original language

About Lorena

🤝 Lorena in a nutshell:

🌟 I am passionate about data engineering. I have 4.5 years of experience and have worked with clients in various sectors.

🚀 I help companies design, migrate, optimize, and automate their data pipelines. I also contribute to identifying the best technical and architectural choices and to knowledge transfer.

📚 I create content in Data Engineering and support Data Engineers in their technical growth. I explain highly technical concepts in a simple and practical way.

⚡️ What I do:
âś… Data pipeline implementation (ETL/ELT)
âś… DataOps

🛠️ Tools & technologies:
Cloud & Data Platforms: AWS (Glue, ECR, Lambda, EC2, Athena, S3, Data Catalog,...)
Data Engineering: PySpark, Python, Databricks, dbt
Infrastructure: IaC, Terraform, CloudFormation
CI/CD: Docker, ECR, Github Actions, Git, Gitlab CI/CD
Orchestration: Airflow, MWAA


đź’ˇ Why work with me?
- I am passionate about Data Engineering
- I am a very good communicator, I can convey highly technical concepts to technical or non-technical audiences
- I can provide customized and effective solutions
- I have experience in consulting
- I am business-oriented, and I understand and interpret client needs very well.
  • French

    Native or bilingual

  • English

    Native or bilingual

Can work on-site
Paris (up to 10km)

Experience

  • Decathlon
    DATA ENGINEER CONSULTANT
    May 2023 - November 2024 (1 year and 6 months)
    Paris, France

    Context:

    • Strategic mission led by Decathlon central: complete migration of 50+ critical pipelines from Redshift to Databricks and decommissioning of legacy infrastructure.
    • Challenges: reduction of infrastructure costs, performance improvement, and unification on the group's Databricks stack.

    Tasks performed:

    • Implementation of data pipelines in the existing Lakehouse architecture (Bronze/Silver/Gold medallion)
    • Analysis of existing mapping: audit of 50+ Redshift pipelines, identification of dependencies.
    • Data modeling in the Gold zone: creation of optimized dimensions according to the Kimball standard adapted for retail.
    • Migration and adaptation of 50+ legacy pipelines to the different Delta Lake layers with dbt or pyspark depending on complexity
    • Refactoring of complex business logic
    • Implementation of advanced Spark optimization techniques: Z-ordering, broadcast joins
    • Implementation of CI/CD pipelines with GitHub Actions: automated tests, multi-environment deployment (dev/preprod/prod)
    • Migration of orchestration based on cron tasks/AWS schedulers to MWAA.
    • Implementation of data quality tests with dbt tests and custom PySpark controls on Databricks.
    • Training of local teams on new technologies and best practices.
    Technical Stack: Databricks, Delta Lake, dbt Core, PySpark, Airflow (MWAA), GitHub
    Actions, s3, AWS ECR
  • Michelin
    DATA ENGINEER CONSULTANT
    December 2024 - April 2025 (4 months)

    Context:

    • Specialized consulting mission to support Michelin teams (France + India) in adopting dbt and Databricks.
    • Leveraging expertise gained during the Decathlon mission to transfer Modern Data Stack best practices.
    • Objective: upskilling teams and exploring technical possibilities through PoCs.

    Tasks performed:

    • • Supporting teams on advanced dbt usage (modeling, testing, documentation)
    • Responding to specific technical needs and resolving complex blockers
    • Developing PoCs to demonstrate advanced dbt capabilities
    • Technical benchmark and comparison of orchestration solutions (Airflow vs Dagster vs Prefect) through practical PoCs
    • Implementation of advanced patterns: lineage, automated data quality checks (Great Expectations, Elementary)
    Technical Stack: dbt core (advanced Jinja templating, custom macros), Airflow,
    Dagster, Prefect, Python, SQL, Great Expectations, Elementary
  • PSA
    DATA ENGINEER CONSULTANT
    November 2022 - April 2023 (5 months)

    Context:

    • Processing of 1TB+ of financial data (Belgium and Netherlands) with high availability and performance requirements

    Tasks performed:

    • Development and optimization of Spark pipelines (Pyspark) for processing large volumes of financial data
    • Implementation of new data pipelines according to evolving business needs
    • Preventive and corrective maintenance of the Datalake: performance monitoring, troubleshooting.
    Technical Stack: Apache Spark, SQL, DBeaver, Python

Recommendations

Be the first to recommend Lorena

Help this freelancer shine by sharing your experience working together.

These freelancer profiles also match your criteria

AgathaA

Agatha Frydrych

Backend Java Software Engineer

4.7

(3)

2

BaptisteB

Baptiste Duhen

Fullstack developer

4.6

(4)

5

AmedA

Amed Hamou

Senior Lead Developer

4

(2)

7

AudreyA

Audrey Champion

Web developer

4.3

(3)

4

Education

  • Engineering Degree
    ESIGELEC
    2020
    Data Ingenierie, DevOps, Architecture et services cloud, Big Data

Certifications

  • Databricks Certified Data Engineer Associate
    Databricks
    2023
    Delta Lake Databricks
  • Databricks Certified Associate Developer for Apache Spark
    Databricks
    2025
    PySpark Databricks Apache Spark

Skill set (37)

Categories