docs: mention zig build -h in readme

 README.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/README.md b/README.md
index a3f7577..1a11941 100644
--- a/README.md
+++ b/README.md
@@ -72,6 +72,7 @@ Then run, for example:
 zig build -Doptimize=ReleaseSafe --prefix ~/.local install
 ```
 To enable Xwayland support pass the `-Dxwayland` option as well.
+Run `zig build -h` to see a list of all options.
 
 ## Usage