diff --git a/src/cook/fs.rs b/src/cook/fs.rs
index b46ec5e0..b32558bf 100644
--- a/src/cook/fs.rs
+++ b/src/cook/fs.rs
@@ -301,6 +301,7 @@ pub fn get_git_head_rev(dir: &PathBuf) -> Result<(String, bool), String> {
     }
 }
 
+/// get commit from "rev" which either a full commit hash or a tag name
 pub fn get_git_tag_rev(dir: &PathBuf, tag: &str) -> Result<String, String> {
     if tag.len() == 40 && tag.chars().all(|f| f.is_ascii_hexdigit()) {
         return Ok(tag.to_string());
diff --git a/src/cook/ident.rs b/src/cook/ident.rs
index 85359956..586e41d1 100644
--- a/src/cook/ident.rs
+++ b/src/cook/ident.rs
@@ -14,7 +14,7 @@ impl IdentifierConfig {
         let (commit, _) = crate::cook::fs::get_git_head_rev(
             &std::env::current_dir().expect("unable to get $PWD"),
         )
-        .expect("Can't read this repository commit");
+        .unwrap_or(("".into(), false));
         // better than importing heavy deps like chrono
         let time = String::from_utf8_lossy(
             &Command::new("date")