César Aguilar

Head of Data @Playtelecom

Mexico City, Mexico

About

Experienced and impact-driven data leader with over 10 years of experience using technology to improve business performance and people’s lives. Proven success in building and scaling data teams, infrastructure, and analytics platforms from the ground up. Skilled at designing and delivering end-to-end solutions—from prototyping to production—and aligning technical execution with real-world business needs. Known for combining a high standard of technical rigor with a people-centered leadership style that fosters ownership, creativity, and measurable impact. Currently Head of Data at Rocketel, where I lead the data & analytics department. I define strategic data initiatives and oversee the full data lifecycle, including infrastructure, ETL pipelines, software platforms, analytics, and automated reporting. I specialize in launching new data functions and accelerating tangible value through quick iterations, prototypes, and lean experimentation.

Experience

  • Head of Data at Playtelecom
    Nov 2022 - Present · 3 yrs 9 mos

    • Founded the company’s data & analytics department, owning end-to-end architecture: cloud infrastructure, data lake, databases, ETL pipelines, orchestration, analytics, and delivery. • Designed and implemented a company-wide data model and reporting platform using Metabase, enabling automated, self-service analytics across departments, serving 30 direct users and over 200 stakeholders. • Recruited, built, and led a 4-person data & analytics team, designing a structured technical onboarding program that brought new hires to independent productivity within 2 months. • Partnered with finance, commercial, and operations to drive a 5X increase in gross margins and a 2X increase in sales for top vendors. • Achieved a 90% reduction in compliance, commercial, and finance reporting time through automation. • Led the development of an iterative AB testing process including sampling, experimental design, and performance evaluation, resulting in a 5% increase in monthly revenue. • Rebuilt the company's billing system from scratch, integrating multi-carrier and SAP ETL with a custom billing rule engine, reducing compute costs by 90%, and eliminating dependency on an external vendor. • Overhauled the company's internal portal, implementing call retrieval and storage with lifecycle management, and replacing the data layer with embedded Metabase dashboards, cutting cloud costs by 95%. • Designed and deployed a natural language data analysis agent using LangGraph, enabling secure, tool-augmented access to internal databases for analytical queries, containerized with Docker.

  • Graduate Researcher at Texas A&M University
    May 2021 - Aug 2022 · 1 yr 4 mos

    • Designed and developed an adaptive VR training system, using a Bayesian network for cognitive workload classification from physiological sensor data, driving dynamic difficulty in a Unity-based cockpit simulation. • Recruited and trained a software development team in Python, C#, Unity VR, and sensor data extraction, delivering a functional prototype within 4 months. • Conducted a human subjects study with a pre-test/post-test design and ANOVA testing, finding a trend suggesting improved performance and reduced workload under adaptive vs non-adaptive training • Published project findings in two highly impactful academic papers, with more than 30 combined citations, demonstrating top-percentile impact within the engineering field.

  • Senior Data Scientist at Citibanamex
    Jan 2019 - Aug 2020 · 1 yr 8 mos

    • Designed and built an interactive data visualization tool improving analysis lead time by 25%. • Implemented ML models predicting response rate and loan amounts, enabling client-level pricing simulation for portfolio optimization, resulting in a 30% increase in net credit margin. • Performed a multi-product offer optimization process, using NPV-based valuation to identify the optimal product combination per client, controlling for credit risk and total loan amount. • Monitored strategy effectiveness with pre-post control, random sample, and stratified sampling techniques. • Managed the department’s model risk management reviews, achieving 100% approval for all models. • Experience with statistical and business-defined feature engineering process from machine learning feature generation and selection. • Presented analyses and results to senior stakeholders, fomenting visibility, and feedback.

  • Data Scientist at Gestell
    Jan 2018 - Jan 2019 · 1 yr 1 mo

    • Managed internal and outsourced development teams, aligning the tasks to the business objectives. • Translated business requirements to features for the first Money Laundering Prevention software prototype of Mexico’s National Banking and Securities Commission (CNVB). • Developed PostgreSQL querying, REST API communications from database to JavaScript front-end. • Conducted technical presentations including sales and prototyping with C-level client representatives.

  • Process and Quality Analyst at Telefónica
    May 2016 - Aug 2017 · 1 yr 4 mos

    • Implemented speech analytics software to automate quality scoring in contact centers, with a 100x rise in capacity. • Used scored data to identify opportunities in customer service, improving first call resolution by 15%. • Designed the customer experience quality evaluation, which was nationally applied on a monthly basis. • Collaborated in the design of customer experience quality evaluation using the COPC standard. • Analyzed, simplified, and organized standard operating procedures for the call center and physical stores.