Archive - The Polymathic Engineer

Authentication Fundamentals: Part I

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

Jan 31 • Franco Fernando

Software Design Principles That Matter

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

Jan 23 • Franco Fernando

Treaps: A Hybrid Data Structure

How to Combine Trees and Heaps for Efficient Data Management.

Jan 16 • Franco Fernando

From Stateful to Stateless: Building Web Apps That Scale

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

Jan 9 • Franco Fernando

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

Control Planes and Data Planes

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

Dec 20, 2025 • Franco Fernando

Fundamental Graph Algorithms Part III: DFS On Directed Graphs

How depth-first search shines on directed graphs: topological sorting and strongly connected component algorithms

Dec 13, 2025 • Franco Fernando

Fundamental Graph Algorithms - Part II: DFS

Depth First Search and its applications on undirected graphs: finding cycles and articulation vertices.

Dec 6, 2025 • Franco Fernando

November 2025

Fundamental Graph Algorithms - Part I: BFS

Breadth First Search and its applications: shortest paths, connected components and bipartite testing.

Nov 29, 2025 • Franco Fernando

How the Operating System Manages the Hardware

A Complete Guide to understand what happens when a program runs on your computer.

Nov 21, 2025 • Franco Fernando

Scaling the data storage layer in system design

A quick journey through replication, partitioning, and NoSQL databases.

Nov 14, 2025 • Franco Fernando

How to Estimate the Duration of a Task

Eight strategies you can use to give better estimations as a software engineer.

Nov 7, 2025 • Franco Fernando

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