diff --git a/bin/ethlambda/src/main.rs b/bin/ethlambda/src/main.rs
index 1b145d9..f973582 100644
--- a/bin/ethlambda/src/main.rs
+++ b/bin/ethlambda/src/main.rs
@@ -55,6 +55,8 @@ struct CliOptions {
     #[arg(long, default_value = "5054")]
     metrics_port: u16,
     #[arg(long)]
+    data_dir: PathBuf,
+    #[arg(long)]
     node_key: PathBuf,
     /// The node ID to look up in annotated_validators.yaml (e.g., "ethlambda_0")
     #[arg(long)]
@@ -130,7 +132,7 @@ async fn main() -> eyre::Result<()> {
     let validator_keys =
         read_validator_keys(&validators_path, &validator_keys_dir, &options.node_id);
 
-    let backend = Arc::new(RocksDBBackend::open("./data").expect("Failed to open RocksDB"));
+    let backend = Arc::new(RocksDBBackend::open(&options.data_dir).expect("Failed to open RocksDB"));
 
     let store = fetch_initial_state(
         options.checkpoint_sync_url.as_deref(),