blog post: Advent of Code 2025 (#1860)

* blog post: Advent of Code 2025

* add a little fundraising pitch

* credit Jamie

* Apply suggestion from @bishabosha

* Apply suggestion from @SethTisue

tiny tweak

* change date

---------

Co-authored-by: Jamie Thompson <bishbashboshjt@gmail.com>

Author: SethTisue

blog/_posts/2025-11-23-advent-of-code-announce.md

@@ -0,0 +1,58 @@
+---
+layout: blog-detail
+post-type: blog
+by: Seth Tisue, Scala Core Team; Jamie Thompson
+title: "Join us for the Advent of Code 2025"
+---
+
+## Help the elves!
+
+For the fifth time, the Scala Center is supporting the Scala community's participation in the annual **Advent of Code** challenge for 2025. (See [Advent of Code Recap 2024](https://www.scala-lang.org/blog/2025/01/16/advent-of-code-recap.html) for a recap of 2024's edition).
+
+We hope you will join us!
+
+## What is Advent of Code?
+
+[**Advent of Code**](https://adventofcode.com), created by [Eric Wastl](http://was.tl/), is an annual event consisting of a series of Christmas-themed programming puzzles. The puzzles are released daily from December 1st through December 12th. The puzzles start easy and get harder as they go.
+
+The goal for participants is pure enjoyment. But also, you can sharpen your coding skills and improve your knowledge of your programming language of choice (which is Scala, of course).
+
+Note that the event is now 12 days long, not 25 days like previous years.
+
+## Discord channel
+
+We have re-opened the `#advent-of-code` [Discord channel](https://discord.com/channels/632150470000902164/913451015246868530) at the official [Scala Discord Server](https://discord.com/invite/scala).
+
+Here you can discuss the puzzles, share solutions, and ask for help.
+
+The channel topic also has a link to a Scala-specific leaderboard, with a code for joining.
+
+## Read sample solutions on our website
+
+Our [Scala Center Advent of Code website](https://scalacenter.github.io/scala-advent-of-code/2025/) is ready to go for 2025.
+
+Once the event begins, we will post a daily article for each puzzle, a day or two after you've had a chance to solve it yourself.
+
+Each article shows a sample solution and explains how it works. Articles are contributed by community members and vetted by the community and the Center.
+
+We want to showcase how Scala helps you write elegant solutions out-of-the-box, so the sample solutions will only use the Scala 3 standard library.
+
+## Share your solutions
+
+If you would like to write one of the sample articles, you can volunteer [on this page](https://github.com/scalacenter/scala-advent-of-code/discussions/842).
+
+Each day's article also includes links to alternate solutions. To add your own solution link, click "Edit this page" on a puzzle page to make a pull request adding a link to your solution.
+
+## Why we do this
+
+At the [Scala Center](https://scala.epfl.ch), we love writing code in Scala, and we hope you do too. One of our core priorities is to _communicate excitement about Scala_, which motivates us to participate in the Advent of Code and share experiences solving problems with Scala with the wider programming community.
+
+Another key priority is to improve the _onboarding experience for newcomers_. Part of that experience comes from the first impressions someone has reading Scala code. We hope that by reading the articles on [our solutions website](https://scalacenter.github.io/scala-advent-of-code/), newcomers can see that Scala is an elegant language for solving problems.
+
+Please urge your employer to [support the Scala Center](https://scala.epfl.ch/donate.html).
+
+## Conclusion
+
+We thank [@spamegg1](https://github.com/spamegg1) for co-organizing.
+
+See you soon and happy coding!