Data Engineer and Developer in Bogotá - Bogota, Colombia

The metadata of the data lake was maintained offline and not always up to date.
Taking this functionality one step further, I created a Python-based query tool to discover actual data in the data lake without querying existing tables.

The tool queries the metadata of the data lake with string filter capability to reduce end queries to the resulting objects (tables and columns). Queries are built dynamically with a filter value to search in the resulting objects.

For example:
The user enters a string to filter the table names containing that string and optionally another string to return those tables, including a field with that second string. Then an additional parameter string to be used as a filter clause on the resulting areas is added.
The end report is a frequency table of records found in those tables containing that field with that value.

Challenges:
Local development environments are inherently limited. There was no possibility to easily share results nor engage other team members in model development.

The existing codebase was inefficient, which resulted in a slow development speed. Since the company required multiple similar models to be developed, this did not align with its long-term goals.
The existing codebase was not following best practices, which made it expensive to maintain, with each further code change costing the company both money and time.

Local model development was not sustainable. Without versioning and keeping track of models, it was impossible to reuse them across different applications.

Model migration: From local development to cloud-based notebooks.
I refactored and optimized a locally developed student loan financial model. The effects of our work could be seen immediately; after refactoring, the model could run 12x times faster compared to its initial inference speed. I migrated the local codebase to a cloud-based notebook environment, created a guided model development flow, and provided technical support.

The Global Fund had limited capability for analytics of the HR activity managed in Oracle e-Business Suite and SumTotal. A DWH was already in production from a prior team, but I identified a design flaw and alerted the project team about its long-term viability. Having committed to the project and its delivery schedule, the client decided to continue the analytics platform development.

Following various interviews with HR business partners and managers, around ten core metrics were highlighted, and dimensions were identified to slice these metrics. At the end of the successful delivery of interactive dashboards on Oracle OBIEE, the HR users noticed degrading query performance over time due to the design flaw of the DWH.

I went back to the DWH design and modified it, reducing data volume by 95%, improving query performance by 40%. This correction was done without affecting the analytics application, which has three layers (physical, logical, presentation) separate from each other.

Testimonial from Mike Hayward: "Stephane got us to a stable platform, we moved into a second phase of delivering even more productivity from BI. I wholeheartedly recommend him not only for his technical skills but his attitude and his social skills."

Groupe FLO Testimonial: "Stéphane is a passionate, enthusiastic, and competent BI and ERP professional. EBS, OBIEE, databases fascinate him. His optimistic character allows him to integrate into teams and forge lasting relationships."— MC Jaurand, IT Manager.

Technip Testimonial: "Stephane was a great contributor to deploy our BI strategy using OBIEE. His knowledge of the tool, along with his business understanding, was instrumental to the success of our project. " —Jean-Luc Brunat, VP TechnipFMC.

The Global Fund Testimonials: "Stéphane was initially brought in to rescue a BI project on the verge of collapsing. In a matter of a few weeks, he proposed an action plan and rebuilt the entire BI layer." —Stephane Vignoud, Data and Integration Manager.

"Stéphane got us to a stable platform and delivered even more productivity from BI. I wholeheartedly recommend Stéphane, not only for his technical skills but his attitude and social skills." —Mike Hayward, HR at Global Fund.