diff --git a/sim/mcuboot-sys/src/lib.rs b/sim/mcuboot-sys/src/lib.rs
index 2da90ef..16bd6c3 100644
--- a/sim/mcuboot-sys/src/lib.rs
+++ b/sim/mcuboot-sys/src/lib.rs
@@ -2,6 +2,11 @@
 #[macro_use] extern crate log;
 extern crate simflash;
 
-pub mod area;
+mod area;
 pub mod c;
+
+// The API needs to be public, even though it isn't intended to be called by Rust code, but the
+// functions are exported to C code.
 pub mod api;
+
+pub use area::{AreaDesc, FlashId};