Blog post for December release

Author: egranata

blog/2025_12/post.md

@@ -0,0 +1,47 @@
+---
+title: "What's New in Aria - December 2025"
+description: "Highlights from the December 2025 Aria release."
+---
+
+# What's New in Aria - December 2025
+
+To give Aria more time to fully bake, the release plan for 1.0 has been adjusted. The new target date for Aria 1.0 is April 2026.
+
+With this change, the language is entering a stabilization phase. The primary focus is now on correctness, bug fixes, and small quality-of-life improvements. Major new features are intentionally out of scope as we move toward 1.0.
+
+## Standard Library
+
+* `File.writeln` actually writes a newline at the end (oops)!
+
+* `List` and `String` values allow negative indices with Python-style semantics.
+
+* Multiplying a `List` or `String` by a negative integer now returns an empty value.
+
+* `MixinRng.one_of` now fails explicitly when given an empty list.
+
+* String character classes now fully support Unicode values.
+
+* Fixed `Instant` to handle negative timestamps (before the Unix epoch) correctly in all cases.
+
+* `String.hash` now produces distinct values for anagrams.
+
+## Core Language
+
+* The `<<=` and `>>=` assignment operators are now supported.
+
+* `\r` is now recognized as a valid escape sequence.
+
+* In `match` statements, `case Foo(x)` now fails cleanly if `Foo` has no payload, instead of triggering a VM error.
+
+## REPL
+
+* The REPL input parser now accepts comments, making it easier to paste larger or annotated code snippets.
+
+---
+
+## Aria Release
+**Download Aria today** The latest version [v0.9.20251222](https://github.com/arialang/aria/releases/tag/v0.9.20251222) is available on GitHub, with prebuilt binaries for Linux and macOS.
+
+Prefer to build from source? Clone the [repo](https://github.com/arialang/aria) and get the freshest bits.
+
+---

blog/index.md

@@ -11,6 +11,8 @@ Expect a monthly **"What's New in Aria"** post, plus occasional deep dives and f
 
 ## Posts
 
+* [What's New in Aria - December 2025](2025_12/post.md)
+
 * [What's New in Aria - November 2025](2025_11/post.md)
 
 * [What's New in Aria - October 2025](2025_10/post.md)