diff --git a/co-noir/co-ultrahonk/src/prover.rs b/co-noir/co-ultrahonk/src/prover.rs
index f0f899f4..7670ef9f 100644
--- a/co-noir/co-ultrahonk/src/prover.rs
+++ b/co-noir/co-ultrahonk/src/prover.rs
@@ -43,7 +43,7 @@ where
     }
 
     pub fn prove(
-        &mut self,
+        mut self,
         proving_key: ProvingKey<T, P>,
     ) -> HonkProofResult<HonkProof<TranscriptFieldType>> {
         tracing::trace!("CoUltraHonk prove");
diff --git a/co-noir/co-ultrahonk/tests/poseidon.rs b/co-noir/co-ultrahonk/tests/poseidon.rs
index 33b2878c..1b8285a1 100644
--- a/co-noir/co-ultrahonk/tests/poseidon.rs
+++ b/co-noir/co-ultrahonk/tests/poseidon.rs
@@ -24,7 +24,7 @@ fn poseidon_plaindriver_test() {
     let prover_crs = ProvingKey::get_prover_crs(&builder, CRS_PATH_G1).unwrap();
     let proving_key = ProvingKey::create(&driver, builder, prover_crs);
 
-    let mut prover = CoUltraHonk::new(driver);
+    let prover = CoUltraHonk::new(driver);
     let proof = prover.prove(proving_key).unwrap();
     let proof_u8 = proof.to_buffer();