diff --git a/build.rs b/build.rs
index be94c38c..cc1fe41f 100644
--- a/build.rs
+++ b/build.rs
@@ -3,10 +3,12 @@
 use std::process::Command;
 
 fn main() {
-    let output = Command::new("git")
+    if let Some(output) = Command::new("git")
         .args(&["rev-parse", "HEAD"])
         .output()
-        .unwrap();
-    let git_hash = String::from_utf8(output.stdout).unwrap();
-    println!("cargo:rustc-env=GIT_HASH={}", git_hash);
+        .ok()
+    {
+        let git_hash = String::from_utf8(output.stdout).unwrap();
+        println!("cargo:rustc-env=GIT_HASH={}", git_hash);
+    }
 }