diff --git a/README.md b/README.md
index 611260470f12b..e251e74b9baf7 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,6 @@
+> [!NOTE]
+> This forked repository was historically used to run CI for the Rust compiler. Since May 2025, all CI has been migrated to the [rust-lang/rust](https://github.com/rust-lang/rust) repository, and this fork is thus no longer used for anything.
+
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