diff --git a/Cargo.toml b/Cargo.toml
index 39cf096..7c13915 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -15,6 +15,10 @@ edition = "2018"
 travis-ci = { repository = "crate-ci/defenestrate" }
 appveyor  = { repository = "epage/defenestrate" }
 
+[features]
+# Support quickly iterating
+iterate_unstable = []
+
 [dependencies]
 failure = "0.1"
 structopt = "0.2"
diff --git a/build.rs b/build.rs
index ff8d85b..e5325d8 100644
--- a/build.rs
+++ b/build.rs
@@ -24,6 +24,7 @@ fn main() {
     for record in &records {
         let value = format!(r#""{}""#, &record[1]);
         builder.entry(unicase::UniCase(&record[0]), &value);
+        #[cfg(features = "iterate_unstable")]
         break;
     }
     builder.build(&mut file).unwrap();