Sites like leanpub.com

Dove Letter by skydoves: a subscription newsletter and resource hub on Android, Kotlin and Jetpack Compose development

A society-run site offering training, events and resources for technical coaches who help software teams adopt better coding practices, using the Samman method

Bartosz Konieczny's blog on data engineering, Databricks, Apache Spark, Kafka, SQL and Java topics

Asciidoctor, an open source Ruby text processor and toolchain converting AsciiDoc to HTML5, DocBook, PDF, and EPUB, with documentation and news

A book on large language models, from how they are built to how they work, by Andriy Burkov, with companion notebooks

A podcast about maintaining and modernizing inherited software legacy code, created in 2016 by Andrea Goulet and M. Scott Ford

Event-Driven, a blog, talks and guides by Oskar Dudycz on software architecture, Event Sourcing, CQRS and event-driven design

Adventures in R, an online course in R programming for statistics and data science, with lessons, puzzles and labs

OnionScan, a free open source tool for investigating and scanning Dark Web onion services for security and privacy flaws

Econometrics and Free Software, a blog by Bruno Rodrigues on R, Nix, econometrics and data science, with books and talks

The official home of the Haskell programming language, covering its compiler GHC, build tool Cabal, installer GHCup and community resources

Personal site of economist Mauricio Vargas Sepúlveda, a PhD student, with blog posts on trade and R tools

Babel, an open-source JavaScript compiler project with documentation, a browser REPL and a team page, converting modern JavaScript to older-compatible code

Software testing exercises, puzzles and essays by James Lyndsay, with free activities and paid subscriber extras, published on the Workroom Productions site

A personal blog by Jeff Geerling on software development, Raspberry Pi and maker hardware, and open source tech news

Alex's blog on Swift and iOS development, covering Swift 6 migration, SwiftPM, Xcode, and his open-source tools like Pulse

Plurality Resource is an online education site with classes taught by and for plural systems, multiples, and medians, plus a blog and newsletter

A blog and podcast by iOS software developer Ben Dalton on app development, Swift, and consulting services (name check: AppForce1 by a developer)

ESLint project website: documentation, playground and team pages for ESLint, the pluggable open-source JavaScript linter

A Java library documentation site for Instancio, a tool that generates random, fully populated test data objects

Luca Mezzalira's personal site on software architecture, micro-frontends and serverless, with books, talks and articles by the AWS solutions architect

Kent Beck's website: software design essays, coaching, newsletters and books on Extreme Programming and Test-Driven Development by its creator

A web framework for building scalable web applications in Java and Scala, with documentation and source code on GitHub

The Pragmatic Studio, an online video course studio teaching programming languages such as Ruby, Elixir and OTP to developers

A German-language site of WebGL experiments by software developer StoneQuest, showcasing real-time 3D graphics demos in the browser

Uiua is an array-oriented programming language, with its homepage linking to installation, documentation and a language tour

Ramda, a documentation site for a practical JavaScript functional programming library and its function reference

Personal site of Victoria Gonda, an Android developer, covering her blog posts, conference talks on testing, accessibility and Android

A design and development agency that builds web and mobile products, with case studies and services from thoughtbot

Laradock, an open-source Docker environment for running PHP and Laravel projects with pre-configured containers and a command-line setup tool

A personal blog by Joapen on Claude Skills, stablecoins, crypto markets, project management, leadership and savings and investment routines

PlantUML, an open-source tool that draws UML diagrams from simple text descriptions, with a Q&A forum and German edition