Senior Data Scientist
Data Scientist
Available for hire
Years of
experience
8+ years
Experience
level
Senior
Available
for
Full-time, Contract, Freelance
Available from
23 Jun 2026
+8 years building production ML systems: ranking, LTV, experimentation, and LLM applications across subscriptions, marketplaces, and logistics
Spent the last eight years convincing computers to make decent predictions and executives that nobody can predict next week's lottery numbers. Expert at explaining why everyone's favorite metric is wrong and why that 99.9% accuracy model definitely won't work in production. Fluent in the art of setting realistic expectations and building pipelines that don't wake the team at 3am. Have mastered the dark art of productive async collaboration across time zones without losing sanity.
Skills
Employment History
Senior Data Scientist at
RevenueCat
Current
2025
-
Now
Owned multiple ML initiatives end-to-end as the sole data scientist on a cross-functional team, from opportunity sizing and product definition to deployment.
Built and productized a per-user subscription signal (7-day subscription probability), scored at install time across all apps and exposed to developers; on holdout, top-decile predictions converted at 1.46x the average (uplift@10).
Improved experiment winner prediction accuracy by +12pp by shipping an end-to-end predicted LTV feature (survival modeling, training pipelines, backend, and frontend integration).
Quantified ~$960K/year in unrealized revenue across 11K+ experiments through counterfactual simulation, then designed a Thompson Sampling allocation approach with inverse probability weighting.
Validated a 5x lift in paid conversion rate from granular engagement signals, and led the design of a real-time behavioral event pipeline to collect them at scale.
Senior Data Scientist at
Wallapop
2023
-
2025
Led ML initiatives for the search team focusing on matching, ranking, and software best practices. Used Solr as the search engine.
Trained a ranker ML model and deployed it to Solr, improving search-to-transaction ratio by +1.5%, adding 600K€ annually.
Trained and deployed a BERT model for a query classification service. Improved the search-to-transaction ratio by 1%, adding 400K€ annually.
Trained a PoC ranker model that used real-time features such as item popularity. Improved offline NDCG metrics by +10%.
Developed PoC solutions for query understanding (intent extraction from queries and structured attribute extraction from descriptions) using LLMs.
Refactored ETLs from manually executed notebooks to Spark jobs. Reduced execution time from days to hours, improving developer experience and scalability.
Organized events to increase machine learning visibility: internal hackathons, Meetups, and conferences.
Senior Data Scientist at
Stuart
2019
-
2023
Deployed a service that improved ETA accuracy by +30% using a deep learning model. Achieved a +28% improvement in cold-start locations.
Designed and developed pipelines to automatically train, evaluate, and deploy ETA models.
Built a distributed pipeline to process daily all the events dumped from Kafka to S3, allowing DS to analyze and train models on it.
Designed an experimental dispatcher engine to solve the assignment problem using Python and OR-Tools.
Mentored a senior software engineer who wanted to specialize in machine learning and data science.
Data Scientist at
21 Buttons
2019
-
2019
Built a recommender system with implicit data, and an image + text-based clothing classifier.
Data Scientist at
Veepee
2018
-
2019
Built a forecasting model for clearance sales. Created a pricing engine on top of the model.
Data Analyst at
Gauss & Neumann
2017
-
2018
Developed tools for monitoring and optimizing SEM campaigns using Google AdWords and Python.
Education
Msc Physics at
CSIC
2016
-
2017
Bachelor Physics at
Universitat Autonoma de Barcelona
2012
-
2016