diff --git a/src/cli.rs b/src/cli.rs
index adcc629..428b934 100644
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -544,9 +544,10 @@ impl Opts {
             std::fs::create_dir(&self.folder)?;
         }
         let path = self.folder.join("sources.json");
-        let fh = std::fs::File::create(&path)
+        let mut fh = std::fs::File::create(&path)
             .with_context(move || format!("Failed to open {} for writing.", path.display()))?;
-        serde_json::to_writer_pretty(fh, &versions::to_value_versioned(pins))?;
+        serde_json::to_writer_pretty(&mut fh, &versions::to_value_versioned(pins))?;
+        fh.write_all(b"\n")?;
         Ok(())
     }