The Polymathic Engineer

Mastering Recursion: the Foundations

Understanding when to use recursion, how to structure recursive functions, and how to go through any recursive code.

Mar 14 • Franco Fernando

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The Building Blocks of Concurrent Programming

Understanding processes, threads, and how they communicate.

Mar 6 • Franco Fernando

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February 2026

Getting Started with OpenCV: A Practical Introduction

Learn how images work under the hood and build your first computer vision application.

Feb 27 • Franco Fernando

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How to Navigate Performance Reviews Like a Pro

A guide to understanding the system, preparing strategically, and getting the rating you deserve.

Feb 21 • Franco Fernando

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Authentication Fundamentals: Part II

OAuth2 and JWT: the Modern API Authentication Standards.

Feb 14 • Franco Fernando

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A Practical Guide to Types of Machine Learning

Understanding supervised, unsupervised, and reinforcement learning. How to choose the right approach for your problem.

Feb 6 • Franco Fernando

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January 2026

Authentication Fundamentals: Part I

From Passwords to Modern Approaches: sessions-cookies, tokens, API keys, OTP, and SSO.

Jan 31 • Franco Fernando

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Software Design Principles That Matter

A tour over Open-Closed Principle, Dependency Injection, and Inversion of Control.

Jan 23 • Franco Fernando

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Treaps: A Hybrid Data Structure

How to Combine Trees and Heaps for Efficient Data Management.

Jan 16 • Franco Fernando

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From Stateful to Stateless: Building Web Apps That Scale

A Practical Guide to Managing State and Building Scalable Web Applications.

Jan 9 • Franco Fernando

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December 2025

End of year wrap: 2025

A personal retrospective on the this year. Plus some thoughts about this newsletter and the most-read articles of the year.

Dec 27, 2025 • Franco Fernando

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Control Planes and Data Planes

A not-well-known pattern for designing better distributed systems.

Dec 20, 2025 • Franco Fernando

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