Hello! I’m Javier Porras-Valenzuela, a fourth-year PhD student in the Electrical and Systems Engineering (ESE) department at the University of Pennsylvania, advised by Professor Alejandro Ribeiro. My research interests include: graph machine learning, constrained learning, optimization, and reasoning.

In a past life, I worked as an ML engineer for 7+ years, during which I applied machine learning and operation research methods to Supply Chain, Fraud Detection, and AdTech.

I am currently looking for internship opportunities for Summer 2027!

Education

• PhD Electrical and Systems Engineering, (2023-present) University of Pennsylvania.
• MSc Computer Science, summa cum laude (2022) Instituto Tecnológico de Costa Rica (ITCR).
• BSc Information Systems Engineering, (2015) Universidad Nacional de Costa Rica (UNA).

Publications

• A Constrained Optimization Perspective of Unrolled Transformers
  ICML 2026 — Spotlight (top 2.2%). Also at the COML Workshop @ NeurIPS 2025.
• Size-Transferability of Graph Transformers with Convolutional Positional Encodings
  Preprint. Also at the NPGML Workshop @ NeurIPS 2025
• Loss Shaping Constraints for Long-Term Time Series Forecasting
  ICML 2024
• A Deep Reinforcement Learning Approach to Multistage Stochastic Network Flows for Distribution Problems
  Master’s Thesis, ITCR, 2022