A handful of resources I recommend to anyone who wants to become a better software engineer.
System Design
The Big Ideas Behind Reliable, Scalable, and Maintainable Systems
How Amazon builds and operates software
A series of system design articles prepared by Microsoft
Learn how to design large-scale systems
A set of mental models and prescriptions for building an app
A list of less common topics in system design
Easy reads about architecture of popular services and systems
React
Cheatsheets for experienced React developers getting started with TypeScript
A map of the libraries worth knowing
A list of general practices when working with React
JavaScript
The new edition of a great book about JavaScript
Extensive ES6 book guide
A series of books diving deep into the core mechanisms of the JavaScript language
Misc.
Simple laws for building cost-aware, sustainable, and modern architectures
Funny guides explaining in a few steps the logic behind DNS resolution
Write down a command-line to see the help text that matches each argument
Classic. What happens under the hood when you enter a query in your browser
The HEAD element in depth
Extensive guide dedicated to regular expressions
Recommended libraries, latest and greatest best practices
This series covers how to solve common problems on JSON datasets with PostgreSQL
Video tutorials for modern ideas and open source tools
A collection of articles on authentication strategies and workflows