Who we are

Thomas Epelbaum

After a french engineering school (ENSTA) and an additionnal Master in theoretical particle physics at Ecole Polytechnique and ENS Ulm Paris, Thomas did a Phd at CEA Saclay and a postdoc at McGill University working on Quantum Chromodynamics .

Wanting to have a more direct impact on society, he started to study Data Science in the summer of 2015, and switched professionaly in the beginning of 2016.

He then spent 6 years in Data Science, Reasearch science, Lead ML R&D Engineer in 3 different SME/startups (mediamobile, Shift Technology (the 13th french unicorn) and Collective Thinking.

Among other things, he released during his pure ML time a white book on deep learning in 2017 (1.4K stars on Github )

Glancing more on more on the pure devs aspects year after year, Thomas joined EcoAct in 2022 as a senior python developer, and is now head of the python developments.

At EcoAct, he developed from scratch more than 30 web app -- most small of course, but some also large like the Climate Risk Platform -- and helped other developers released another ten more applications. All that would not have been possible without Tiangolo, Samuel Covin (that Thomas thanks again), and the ecodev project!

At a personal level, Thomas likes (a lot :) ) reading on economy, philosophy, sociology and biology, spending time in the Alpes (every season), try a new collaborative board game, or play a competitive one. He is quite good at Myrmes (best board game ever 😋)

Olivier Gabriel

A graduate of the Ecole Polytechnique, Olivier did a thesis in mathematics at the Université Paris Diderot, which he defended in 2011.

After 10 years of academic research in Germany the UK and Denmark, he decided to move into the private sector, to work on innovative subjects while maximising his practical impact.

At WeMaintain, he has created and structured the R&D team around an IoT and data project over 4 years, during which time the start-up grew from 15 to 175 employees.

He joined EcoAct in May 2023, to leverage both his scientific and IT experience.

There, he has worked on enriching and harmonising the available data sources and creating tools to speed up and deepen the company's missions.

Amaury Salles

After years abroad and a MSc in Renewable Energy Systems Technologies, Amaury started his career in 2016 as a renewable energy consultant in the UK.

He quickly got interested in programming to find meaning in data and regained the pleasure of creating things other than PDF reports and excel spreadsheets.

In 2019, he converted to full time software engineer and developed software for energy consultants and clients.

In 2020 he increased his data analysis and data science knowledge through night-time classes.

Currently working since 2023 at EcoAct (Paris, FR), where he leverages his previous experiences to create internal consulting tools, with a focus on enhancing UI/UX.

Nerd meets hippy, he enjoys working on digital solutions developed which have concrete applications and a positive impact in the fight against the climate crisis.

Yoann Diep

Yoann originally has a background in Finance, having completed a masters' degree and working for UBS as a Market Risk Analyst.

He then decided to gain more sense in his daily tasks by joining a Consultancy to kickstart their sustainable finance division.

Seeing the constant need to handle large volumes of (mostly unstructured) data in this field, he attended a 6-month long Data Science bootcamp at Le Wagon to learn how to code in Python and use ML techniques to palliate the scarcity of reported environmental data.

Since he joined EcoAct, Yoann has been developping the back and front-end of a portfolio related web platform designed in Dash and postgresql.

Aimed at Financial Institutions to help them measure the emissions resulting from their investment and lending decisions and compute reduction trajectory in line with climate scenarios, so that they can target the most efficient way of reducing their financed emissions.

Dorian Kodelja

After a PhD in Natural language processing, Dorian joined Collective Thinking, a company focused on leveraging artificial intelligence for clinical coding and clinical research.

For 3 years, as a machine learning engineer with an interest in DevOps, he was both working on improving the AI models performance and the reliability of the software infrastructure surrounding it.

He joined EcoAct's Climate Data analytics team in 2024 to strengthen its software engineering and machine learning capabilities.

Charles Cuvillier

Charles Cuvillier graduated from Ensta Paris, a French engineering school, where he specialized in applied mathematics, optimization, and data science. He completed a Master’s degree in Data Science at the Polytechnic Institute, gaining strong skills in analytics and quantitative modeling.

He worked as a data scientist in two start-ups (Bib batteries and NEOT), developing AI-based methods to assess and forecast the health of electric vehicle batteries using statistical techniques. He also completed a research internship at University College Dublin, contributing to a paper on mathematics applied to fluid mechanics.

In 2024, he joined the company to help develop decarbonization tools. Passionate about sustainability, he uses data-driven solutions to support the company’s environmental goals and drive positive change.

Thibault Rolland

Thibault holds a degree in mechanical engineering and graduated from École des Ponts ParisTech with a specialization in data science and industrial engineering.

Since then, he has built a hybrid profile at the intersection of applied research, software development, and data science.

He has worked in fast-paced startup environments: he began his career at Shift Technology, developing machine learning solutions to detect fraud for international insurance clients. He later joined Madkudu, a startup focused on applying AI to B2B sales, where he contributed as a software and data engineer.

He has contributed to a range of applied research projects. He worked at the Paris Brain Institute where he was part of NERV, a team specializing in brain-computer interfaces. He designed data processing algorithms and developed interactive visualization tools to support neuroscientific research. ( i , ii)

For a year, he worked at ACSS-PSL, a research chair focused on AI for social sciences. There, he fine-tuned large language models for applications in advertising and political science research.

Thibault joined Ecoact in April 2025 as a software engineer.

Thibault enjoys reading, listening to music and is an unassuming nerd.

Ziad Abdelhalim

After a Bachelor of Engineering in civil engineering from Kyoto University and a Master of Economics at Ecole Polytechnique, Ziad started his career as a Software engineer at Ingerop in 2023.

For 2 years, he worked on developing web and GIS applications focused on carbon footprint analysis and climate risk assessment of civil engineering projects.

Seeking a new challenge and aiming to continue working in a sustainability driven environment, Ziad joined EcoAct's Climate Data analytics team in May 2025 as software engineer to work on tools that facilitate data-driven decision-making, monitor environmental impact, and accelerate the ecological transition.