diff --git a/src/eval/lang.rs b/src/eval/lang.rs
index ec243355ba..43ae0d0a58 100644
--- a/src/eval/lang.rs
+++ b/src/eval/lang.rs
@@ -181,7 +181,7 @@ pub(crate) mod test {
     use crate::sym;
 
     use super::*;
-    use halo2curves::bn256::Fr as Fr;
+    use halo2curves::bn256::Fr;
 
     #[test]
     fn lang() {
diff --git a/src/lem/circuit.rs b/src/lem/circuit.rs
index ce20e0885f..8178f5b770 100644
--- a/src/lem/circuit.rs
+++ b/src/lem/circuit.rs
@@ -1680,6 +1680,8 @@ impl Func {
         let bit_decomp_cost = match F::FIELD {
             LanguageField::Pallas => 298,
             LanguageField::Vesta => 301,
+            // TODO: investigate how to properly compute this number, as it was obtained empirically
+            LanguageField::BN256 => 354,
             _ => todo!(),
         };
 
diff --git a/src/lem/eval.rs b/src/lem/eval.rs
index ff44e14660..19cf6ee63d 100644
--- a/src/lem/eval.rs
+++ b/src/lem/eval.rs
@@ -1726,7 +1726,7 @@ mod tests {
     };
     use bellpepper_core::{test_cs::TestConstraintSystem, Comparable};
     use expect_test::{expect, Expect};
-    use pasta_curves::pallas::Scalar as Fr;
+    use halo2curves::bn256::Fr;
 
     #[test]
     fn test_counts() {
@@ -1745,8 +1745,8 @@ mod tests {
         expect_eq(func.slots_count.commitment, expect!["1"]);
         expect_eq(func.slots_count.bit_decomp, expect!["3"]);
         expect_eq(cs.num_inputs(), expect!["1"]);
-        expect_eq(cs.aux().len(), expect!["8927"]);
-        expect_eq(cs.num_constraints(), expect!["10857"]);
+        expect_eq(cs.aux().len(), expect!["9095"]);
+        expect_eq(cs.num_constraints(), expect!["11025"]);
         assert_eq!(func.num_constraints(&store), cs.num_constraints());
     }
 }
diff --git a/src/lem/store.rs b/src/lem/store.rs
index a1d4ba735c..e5080cbe8b 100644
--- a/src/lem/store.rs
+++ b/src/lem/store.rs
@@ -1346,7 +1346,7 @@ impl Ptr {
 #[cfg(test)]
 mod tests {
     use ff::Field;
-    use pasta_curves::pallas::Scalar as Fr;
+    use halo2curves::bn256::Fr;
     use proptest::prelude::*;
 
     use crate::{