diff --git a/zebra-chain/src/keys.rs b/zebra-chain/src/keys.rs
new file mode 100644
index 00000000..470b5f98
--- /dev/null
+++ b/zebra-chain/src/keys.rs
@@ -0,0 +1,4 @@
+//! Key types.
+
+mod sapling;
+mod sprout;
diff --git a/zebra-chain/src/keys/sapling.rs b/zebra-chain/src/keys/sapling.rs
new file mode 100644
index 00000000..fb72e5f3
--- /dev/null
+++ b/zebra-chain/src/keys/sapling.rs
@@ -0,0 +1,18 @@
+use std::{
+    fmt,
+    io::{self},
+};
+
+#[cfg(test)]
+use proptest::{array, collection::vec, prelude::*};
+#[cfg(test)]
+use proptest_derive::Arbitrary;
+
+use crate::serialization::{SerializationError, ZcashDeserialize, ZcashSerialize};
+
+#[cfg(test)]
+proptest! {
+
+    //#[test]
+    // fn test() {}
+}
diff --git a/zebra-chain/src/keys/sprout.rs b/zebra-chain/src/keys/sprout.rs
new file mode 100644
index 00000000..a7b3f6b0
--- /dev/null
+++ b/zebra-chain/src/keys/sprout.rs
@@ -0,0 +1,18 @@
+use std::{
+    fmt,
+    io::{self},
+};
+
+#[cfg(test)]
+use proptest::{array, collection::vec, prelude::*};
+#[cfg(test)]
+use proptest_derive::Arbitrary;
+
+use crate::serialization::{SerializationError, ZcashDeserialize, ZcashSerialize};
+
+#[cfg(test)]
+proptest! {
+
+    #[test]
+    fn test() {}
+}
diff --git a/zebra-chain/src/lib.rs b/zebra-chain/src/lib.rs
index 988ee6d3..9d01dd28 100644
--- a/zebra-chain/src/lib.rs
+++ b/zebra-chain/src/lib.rs
@@ -10,6 +10,7 @@ mod sha256d_writer;
 
 pub mod block;
 pub mod equihash_solution;
+pub mod keys;
 pub mod note_commitment_tree;
 pub mod note_encryption;
 pub mod proofs;