Other Developer Advent Calendars!

If you know of other 2021 Advent calendars that belongs here, let me know and I'll get them listed here!

• F# Calendar - the inspiration for this site and a tradition that started in 2010 continues!
• Advent of Code - an Advent calendar of small programming puzzles for a variety of skill sets and skill levels that can be solved in any programming language
• Festive Tech Calendar - "lots of new content from different communities and people around the globe"
• .NET Advent Calendar
• Go Advent Calendar