diff --git a/README.md b/README.md
index f104a242..d355d133 100644
--- a/README.md
+++ b/README.md
@@ -28,9 +28,9 @@ version >= 3.6.
 
 ## Building/Packaging
 
-To manually build a package for distribution, run the following steps. This
-process will generate both .tar.gz package and .whl package under `./dist/`
-directory.
+To manually build a package for distribution, run the following steps. You will
+need a C++ compiler which supports C++20 (e.g. `clang++` >= 7 or g++ >= 10). The
+steps will generate both a `.tar.gz` and `.whl` package under `./dist/`.
 
 ```bash
 # 1. Create and enter a virtual environment