diff --git a/poly-commit/src/linear_codes/mod.rs b/poly-commit/src/linear_codes/mod.rs
index 2626adec..e6cd655b 100644
--- a/poly-commit/src/linear_codes/mod.rs
+++ b/poly-commit/src/linear_codes/mod.rs
@@ -160,7 +160,7 @@ where
     C: Config + 'static,
     Vec<F>: Borrow<<H as CRHScheme>::Input>,
     H::Output: Into<C::Leaf> + Send,
-    C::Leaf: Sized + Clone + Default + Send,
+    C::Leaf: Sized + Clone + Default + Send + AsRef<C::Leaf>,
     H: CRHScheme + 'static,
 {
     type UniversalParams = L::LinCodePCParams;
@@ -302,7 +302,7 @@ where
         _labeled_polynomials: impl IntoIterator<Item = &'a LabeledPolynomial<F, P>>,
         commitments: impl IntoIterator<Item = &'a LabeledCommitment<Self::Commitment>>,
         point: &'a P::Point,
-        _challenge_generator: &mut crate::challenge::ChallengeGenerator<F, S>,
+        _sponge: &mut S,
         states: impl IntoIterator<Item = &'a Self::CommitmentState>,
         _rng: Option<&mut dyn RngCore>,
     ) -> Result<Self::Proof, Self::Error>
@@ -395,7 +395,7 @@ where
         point: &'a P::Point,
         values: impl IntoIterator<Item = F>,
         proof_array: &Self::Proof,
-        _challenge_generator: &mut crate::challenge::ChallengeGenerator<F, S>,
+        _sponge: &mut S,
         _rng: Option<&mut dyn RngCore>,
     ) -> Result<bool, Self::Error>
     where
@@ -545,7 +545,7 @@ fn create_merkle_tree<C>(
 ) -> Result<MerkleTree<C>, Error>
 where
     C: Config,
-    C::Leaf: Default + Clone + Send,
+    C::Leaf: Default + Clone + Send + AsRef<C::Leaf>,
 {
     // pad the column hashes with zeroes
     let next_pow_of_two = leaves.len().next_power_of_two();
diff --git a/poly-commit/src/linear_codes/multilinear_brakedown/tests.rs b/poly-commit/src/linear_codes/multilinear_brakedown/tests.rs
index 8af84e5b..e4be256f 100644
--- a/poly-commit/src/linear_codes/multilinear_brakedown/tests.rs
+++ b/poly-commit/src/linear_codes/multilinear_brakedown/tests.rs
@@ -4,7 +4,6 @@ mod tests {
     use crate::linear_codes::LinearCodePCS;
     use crate::utils::test_sponge;
     use crate::{
-        challenge::ChallengeGenerator,
         linear_codes::{utils::*, BrakedownPCParams, MultilinearBrakedown, PolynomialCommitment},
         LabeledPolynomial,
     };
@@ -114,22 +113,19 @@ mod tests {
         );
 
         let mut test_sponge = test_sponge::<Fr>();
-        let (c, rands) = BrakedownPCS::<Fr>::commit(&ck, &[labeled_poly.clone()], None).unwrap();
+        let (c, states) = BrakedownPCS::<Fr>::commit(&ck, &[labeled_poly.clone()], None).unwrap();
 
         let point = rand_point(Some(num_vars), rand_chacha);
 
         let value = labeled_poly.evaluate(&point);
 
-        let mut challenge_generator: ChallengeGenerator<Fr, PoseidonSponge<Fr>> =
-            ChallengeGenerator::new_univariate(&mut test_sponge);
-
         let proof = BrakedownPCS::<Fr>::open(
             &ck,
             &[labeled_poly],
             &c,
             &point,
-            &mut (challenge_generator.clone()),
-            &rands,
+            &mut (test_sponge.clone()),
+            &states,
             None,
         )
         .unwrap();
@@ -139,7 +135,7 @@ mod tests {
             &point,
             [value],
             &proof,
-            &mut challenge_generator,
+            &mut test_sponge,
             None
         )
         .unwrap());