Sites like bogdanberg.com

Free embedded systems tutorials, articles and projects on firmware, microcontrollers and DSP, by engineer Khaled Magdy

A catalogue of free downloadable programming reference books, such as C, R, CSS and Git, titled "Notes for Professionals

Xah Code, a personal website of programming tutorials, math notes, blogs and essays by Xah Lee

A news blog on embedded systems, maker boards and single-board computers such as Raspberry Pi and Arduino, run by CNX Software Limited

BeagleBoard.org is an open hardware single-board computer project offering documentation, forums, books and support for makers, educators and developers

Hackaday.io, a community platform where makers publish and share open hardware development projects and build logs

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The Open Source Geospatial Foundation website, a nonprofit hub supporting geospatial open source software projects, their community, events and governance

Personal home page of Eric S. Raymond hosting his open-source software, FAQs, essays and the Retrocomputing Museum

Homebrew, a package manager for installing software on macOS, Linux and WSL from the command line

FanGraphs Baseball: a blog and podcast on baseball statistics, analysis, and fantasy baseball strategy, with RotoGraphs columns

The LaTeX Project's website on LaTeX, the document preparation and typesetting system for technical and scientific publishing, with downloads, bug reporting, help and licence text

OpenCV, the open-source computer vision library, with its services, training, partner program and blog, run by the OpenCV organisation

SciPy, an open source Python library of algorithms for scientific computing, covering optimization, integration, interpolation, statistics and differential equations

Can I use..., a reference site of browser support tables for web features such as HTML5, CSS3 and JavaScript

A community database and progress tracker for the game IDOLM@STER Cinderella Girls Starlight Stage, with player profiles, maps and a wiki

It's FOSS is an English-language blog on Linux tips, tutorials, applications and news, written by Abhishek Prakash

NuGet is the central package repository and package manager for .NET, with package search, download statistics and client tools

A website builder for creating custom social networks and community sites, with community management and social media integration, offered in several languages

Prettier, an opinionated code formatter for JavaScript, CSS, Markdown and other languages, with editor and CI integrations

Node-RED, an open-source low-code tool for wiring event-driven applications and real-time data flows, with a blog and documentation

Node.js, an open-source cross-platform JavaScript runtime for building servers, web apps, command line tools and scripts

WinSCP, a free open-source SFTP and FTP client application for Windows file transfers between local and remote computers

A Spanish and Portuguese documentation site for Socket.IO, a library for real-time bidirectional communication between clients and servers

ART19 is a podcast hosting platform whose pages list many separate shows, from fiction and AI news to home design

Pocoo, a former team of open source developers behind Python projects Flask, Sphinx, Jinja, Werkzeug and Pygments