Merge pull request rust-lang#6852 from contextgeneric/extensible-variants-impl

Add link to The Design and Implementation of Extensible Variants

Author: nellshamrell

draft/2025-07-30-this-week-in-rust.md

@@ -49,6 +49,8 @@ and just ask the editors to select the category.
 
 ### Rust Walkthroughs
 
+* [The Design and Implementation of Extensible Variants for Rust in CGP (Extensible Data Types Part 4)](https://contextgeneric.dev/blog/extensible-datatypes-part-4/)
+
 ### Research
 
 ### Miscellaneous