diff --git a/Readme.md b/Readme.md
index 0c20811..134d25a 100644
--- a/Readme.md
+++ b/Readme.md
@@ -94,6 +94,13 @@ mach-nix gen -r requirements.txt
 ...to print out the nix expression which defines a python derivation (optionally use `-o` to define an `output file`)
 
 ---
+### Build a derivation or enter a shell from a list of requirements
++ if [Nix flakes is enabled](https://nixos.wiki/wiki/Flakes#:~:text=Installing%20flakes):
+
+  ```shell
+  nix (build|shell) mach-nix#gen.(python|docker).package1.package2...
+  ```
+---
 
 ## Usage in Nix Expression