diff --git a/tools/build/README.md b/tools/build/README.md
index 1444321f972..f3678571582 100644
--- a/tools/build/README.md
+++ b/tools/build/README.md
@@ -17,6 +17,7 @@ The script will skip build steps whose inputs have not changed since the last ru
 
 - On Windows, `BUILD.bat` will automatically install a private (vendored) copy of Node.
 - On Linux, install Node using your package manager or from <https://nodejs.org/en/download/>.
+- On Linux , unless using tgs4 or later you will need to compile rust-g on the server and obtain a .so file, for instructions see https://github.com/tgstation/rust-g
 
 ## Why?