diff --git a/README.md b/README.md
index ca51801..954e9b5 100644
--- a/README.md
+++ b/README.md
@@ -11,7 +11,7 @@ Formally verified implementation of the ARTIQ RTIO core in nMigen
 
 ## Running the verification tasks
 
-Currently, only the sorting network contains assertions to be verified. To run the verification tasks for the sorting network, change directory to the root of this project and do
+Currently, only the sorting network contains assertions to be verified. To run the verification tasks for the sorting network, change directory to the root of this project, set up the [Nix](https://nixos.org) environment by running `nix-shell` and do
 
 ```bash
 $ python -m rtio.test.sed.output_network