diff --git a/README.md b/README.md
index 02942cd..9b84218 100644
--- a/README.md
+++ b/README.md
@@ -10,3 +10,7 @@ $ nix-*-linux/install
 ```
 
 You are in a user chroot where `/` is owned by your user, hence also `/nix` is owned by your user. Everything else is bind mounted from the real root.
+
+Notes:
+
+- The nix config is not in `/etc/nix` but in `/nix/etc/nix`, so that you can modify it. This is done with the `NIX_CONF_DIR`, which you can override at any time.
diff --git a/main.c b/main.c
index 8e6bfff..cc29e7c 100644
--- a/main.c
+++ b/main.c
@@ -114,6 +114,8 @@ path_buf, path_buf2, strerror(errno));
     chdir(cwd);
 
     // execute the command
+   
+    setenv("NIX_CONF_DIR", "/nix/etc/nix", 1);
     execvp(argv[2], argv+2);
     err_exit("execvp");
 }