diff --git a/CLAUDE.md b/CLAUDE.md
index 19dbfa3e..fc52d337 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -241,7 +241,7 @@ errors are also unavailable to us by rule #7.
 
 Plan 9 taste lowered to ww. No CamelCase anywhere in ww source.
 
-- Package names: short, lowercase, one word. `fmt`, `io`, `bio`.
+- Package names: short, lowercase, one word. `fmt`, `io`, `bufio`.
 - Identifiers: lowercase, words run together. `newbuf`, `tcpsock`,
   `parsefile`. Underscores allowed but discouraged.
 - Visibility: the `export` keyword. Not first-letter case.
@@ -267,7 +267,6 @@ lib/
   fmt/          printf-family
   io/           reader/writer/closer interfaces
   bufio/        buffered io (Plan 9 'bio' equivalent)
-  bio/          alias of bufio for Plan 9 muscle memory
   os/           process, fs, args, env
   os/exec/      run subcommands
   errors/       error type, sentinel values