diff --git a/Cargo.lock b/Cargo.lock
index 5ff8bd0..96c31e7 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,191 +1,200 @@
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diff --git a/Cargo.toml b/Cargo.toml
index 9765284..8744910 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,7 +6,7 @@ edition = "2018"
 
 [dependencies]
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+nix = "0.20"
 pam = "0.7"
 quick-error = "1.2"
 users = "0.9"