1 files changed, 7 insertions, 0 deletions
diff --git a/src/db/lib.rs b/src/db/lib.rs
index f185114e..d96586be 100644
--- a/src/db/lib.rs
+++ b/src/db/lib.rs
@@ -1,8 +1,15 @@
 #[macro_use]
+#[cfg(feature = "sqlite")]
 extern crate tracing;
 
+#[cfg(not(any(feature = "lmdb", feature = "sled", feature = "sqlite")))]
+compile_error!("Must activate the Cargo feature for at least one DB engine: lmdb, sled or sqlite.");
+
+#[cfg(feature = "lmdb")]
 pub mod lmdb_adapter;
+#[cfg(feature = "sled")]
 pub mod sled_adapter;
+#[cfg(feature = "sqlite")]
 pub mod sqlite_adapter;
 
 pub mod counted_tree_hack;