diff --git a/.travis.yml b/.travis.yml
index fa4b2c4..00e02c0 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -41,7 +41,7 @@ script:
   - cargo test --features i128_blob
   - cargo test --features uuid
   - cargo test --features "bundled unlock_notify window"
-  - cargo test --features "array bundled csvtab vtab"
+  - cargo test --features "array bundled csvtab series vtab"
   - cargo test --features "backup blob chrono collation csvtab functions hooks limits load_extension serde_json trace url uuid vtab"
   - cargo test --features "backup blob chrono collation csvtab functions hooks limits load_extension serde_json trace url uuid vtab buildtime_bindgen"
   - cargo test --features "backup blob chrono collation csvtab functions hooks limits load_extension serde_json trace url uuid vtab bundled"
diff --git a/Cargo.toml b/Cargo.toml
index 3b335d9..10d21d4 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -51,6 +51,9 @@ array = ["vtab"]
 session = ["libsqlite3-sys/session", "hooks"]
 # window functions: 3.25.0
 window = ["functions"]
+# 3.9.0
+series = ["vtab"]
+
 
 [dependencies]
 time = "0.1.0"
diff --git a/src/vtab/mod.rs b/src/vtab/mod.rs
index f0196c2..2a7191d 100644
--- a/src/vtab/mod.rs
+++ b/src/vtab/mod.rs
@@ -67,6 +67,7 @@ pub struct Module<T: VTab> {
     phantom: PhantomData<T>,
 }
 
+unsafe impl<T: VTab> Send for Module<T> {}
 unsafe impl<T: VTab> Sync for Module<T> {}
 
 /// Create a read-only virtual table implementation.
@@ -984,7 +985,7 @@ fn mprintf(err_msg: &str) -> *mut c_char {
 pub mod array;
 #[cfg(feature = "csvtab")]
 pub mod csvtab;
-#[cfg(feature = "bundled")]
+#[cfg(feature = "series")]
 pub mod series; // SQLite >= 3.9.0
 
 #[cfg(test)]