Welligence (Data Engineer freelance)

Presentation

During my collaboration with Welligence, I worked as a Data Engineer on a tool built for internal data scientists. It was used to scrape and inject data into multiple PostgreSQL databases, as well as generate various reports in PDF and Excel formats.

The role had a strong coordination aspect. Welligence is a U.S.-based company with developers across Europe and Vietnam, and each global economic region had a head of data relying on the tool and working on a different time-zone. This required effective communication skills and experience with Ruby on Rails, Jenkins, Sidekiq, and some Python.

As the company scaled, we faced several reliability and performance challenges. One of my key contributions was building a GeoJSON import feature to visualize oil field shapes on a 3D globe. While the experience was valuable, the role became increasingly support-oriented, with limited opportunities for hands-on development. I decided to move on in search of a position with a stronger focus on software engineering.

Personal impression

This mission was interesting at first, as it brought new challenges related to managing multiple databases — one per country. It was a notable shift from my previous experiences, where a single database served as the main source of truth. Here, the data itself was the product, and refining and versioning it became a key part of the work. I gained valuable knowledge in data handling, and my AWS experience proved to be a real asset.

It was also my first time working directly with a U.S.-based company, which brought a different mindset — especially around scaling, quality standards, and less rigidly defined roles. In the end, I struggled to find my place. The lead developer role had already been filled, and I didn’t fully align with his vision. My responsibilities became more support-oriented, which didn’t match my level of experience or expectations.

Skills