diff --git a/docs/src/index.md b/docs/src/index.md
index 62ff6a07fb5..bf0bca5bee5 100644
--- a/docs/src/index.md
+++ b/docs/src/index.md
@@ -113,7 +113,7 @@ julia --project=.
 if already inside the `run` directory.
 If you encounter errors executing `julia --project=. -e 'using Pkg; Pkg.develop(PackageSpec(path=".."))'`
 it might help to update the packages first:
-`julia --project=. -e 'using Pkg; Pkg.update()'`
+`julia --project=. -e 'using Pkg; Pkg.update()'`.
 
 The advantage of using a separate `run` directory is that you can also add other
 related packages (see below, e.g., for time integration or visualization) to the