diff --git a/halo2-ecc/src/bn254/bls_signature.rs b/halo2-ecc/src/bn254/bls_signature.rs
index 0e10a090..f0b5570d 100644
--- a/halo2-ecc/src/bn254/bls_signature.rs
+++ b/halo2-ecc/src/bn254/bls_signature.rs
@@ -7,6 +7,7 @@ use crate::fields::FieldChip;
 use crate::fields::PrimeField;
 use crate::halo2_proofs::halo2curves::bn256::Fq12;
 use crate::halo2_proofs::halo2curves::bn256::{G1Affine, G2Affine};
+use ff::Field;
 use halo2_base::{AssignedValue, Context};
 
 // To avoid issues with mutably borrowing twice (not allowed in Rust), we only store fp_chip and construct g2_chip and fp12_chip in scope when needed for temporary mutable borrows
diff --git a/halo2-ecc/src/bn254/pairing.rs b/halo2-ecc/src/bn254/pairing.rs
index 886985d4..c11d2a83 100644
--- a/halo2-ecc/src/bn254/pairing.rs
+++ b/halo2-ecc/src/bn254/pairing.rs
@@ -9,6 +9,7 @@ use crate::{
     fields::fp12::mul_no_carry_w6,
     fields::{FieldChip, PrimeField},
 };
+use ff::Field;
 use halo2_base::Context;
 
 const XI_0: i64 = 9;
diff --git a/halo2-ecc/src/ecc/fixed_base.rs b/halo2-ecc/src/ecc/fixed_base.rs
index 5dfba754..df48dcb1 100644
--- a/halo2-ecc/src/ecc/fixed_base.rs
+++ b/halo2-ecc/src/ecc/fixed_base.rs
@@ -2,6 +2,7 @@
 use super::{ec_add_unequal, ec_select, ec_select_from_bits, EcPoint, EccChip};
 use crate::ecc::{ec_sub_strict, load_random_point};
 use crate::fields::{FieldChip, PrimeField, Selectable};
+use ff::Field;
 use group::Curve;
 use halo2_base::gates::builder::{parallelize_in, GateThreadBuilder};
 use halo2_base::{gates::GateInstructions, utils::CurveAffineExt, AssignedValue, Context};
diff --git a/halo2-ecc/src/ecc/mod.rs b/halo2-ecc/src/ecc/mod.rs
index a196e039..48aa24c9 100644
--- a/halo2-ecc/src/ecc/mod.rs
+++ b/halo2-ecc/src/ecc/mod.rs
@@ -1,6 +1,7 @@
 #![allow(non_snake_case)]
 use crate::fields::{fp::FpChip, FieldChip, PrimeField, Selectable};
 use crate::halo2_proofs::arithmetic::CurveAffine;
+use ff::Field;
 use group::{Curve, Group};
 use halo2_base::gates::builder::GateThreadBuilder;
 use halo2_base::utils::modulus;
diff --git a/halo2-ecc/src/fields/fp12.rs b/halo2-ecc/src/fields/fp12.rs
index 156ca452..3a8ce4af 100644
--- a/halo2-ecc/src/fields/fp12.rs
+++ b/halo2-ecc/src/fields/fp12.rs
@@ -1,5 +1,6 @@
 use std::marker::PhantomData;
 
+use ff::PrimeField as _;
 use halo2_base::{utils::modulus, AssignedValue, Context};
 use num_bigint::BigUint;
 
diff --git a/halo2-ecc/src/fields/fp2.rs b/halo2-ecc/src/fields/fp2.rs
index 55e3243a..2e3c8f13 100644
--- a/halo2-ecc/src/fields/fp2.rs
+++ b/halo2-ecc/src/fields/fp2.rs
@@ -1,6 +1,7 @@
 use std::fmt::Debug;
 use std::marker::PhantomData;
 
+use ff::PrimeField as _;
 use halo2_base::{utils::modulus, AssignedValue, Context};
 use num_bigint::BigUint;
 
diff --git a/halo2-ecc/src/lib.rs b/halo2-ecc/src/lib.rs
index 10da56bc..3b88702f 100644
--- a/halo2-ecc/src/lib.rs
+++ b/halo2-ecc/src/lib.rs
@@ -1,7 +1,6 @@
 #![allow(clippy::too_many_arguments)]
 #![allow(clippy::op_ref)]
 #![allow(clippy::type_complexity)]
-#![feature(int_log)]
 #![feature(trait_alias)]
 
 pub mod bigint;
diff --git a/rust-toolchain b/rust-toolchain
index 51ab4759..cb8136f6 100644
--- a/rust-toolchain
+++ b/rust-toolchain
@@ -1 +1 @@
-nightly-2022-10-28
\ No newline at end of file
+nightly-2023-04-19
\ No newline at end of file