diff --git a/src/lib.rs b/src/lib.rs
index 036e36d..837b606 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,2 +1,4 @@
 #[cfg(feature = "naive")]
 pub mod naive;
+
+pub(crate) mod sig;
diff --git a/src/naive/mod.rs b/src/naive/mod.rs
index 139597f..0dfcbb7 100644
--- a/src/naive/mod.rs
+++ b/src/naive/mod.rs
@@ -1,2 +1,21 @@
+use crate::sig::KeyGen;
 
+pub struct SigParams {
+    m: u16,
+    n: u16,
+    o: u16,
+    k: u16,
+    salt_bytes: u8,
+    digest_bytes: u8,
+    pk_seed_bytes: u8,
+}
 
+pub struct SigningKey {
+    v: VerifyKey,
+}
+
+pub struct VerifyKey {}
+
+impl KeyGen<SigParams> for SigningKey {
+    fn gen(params: SigParams) -> Self {}
+}
diff --git a/src/sig.rs b/src/sig.rs
index 90f6680..4627b7e 100644
--- a/src/sig.rs
+++ b/src/sig.rs
@@ -1,6 +1,8 @@
-pub trait Signer<S> {
-    fn gen() -> Self;
+pub trait KeyGen<P> {
+    fn gen(params: P) -> Self;
+}
 
+pub trait Signer<S> {
     fn sign(&self, msg: &[u8]) -> S;
 }