diff --git a/auction/src/lib.rs b/auction/src/lib.rs
index fd8e733d53b258ad42138fb467cd5d3311af558e..18642197d8f85d9d2f88644af74ab4cd9353a801 100644
--- a/auction/src/lib.rs
+++ b/auction/src/lib.rs
@@ -37,9 +37,9 @@ type AuctionIdLinkedItem<T> = LinkedItem<<T as Trait>::AuctionId>;
 
 decl_storage! {
 	trait Store for Module<T: Trait> as Auction {
-		pub Auctions get(fn auctions): map T::AuctionId => Option<AuctionInfo<T::AccountId, T::Balance, T::BlockNumber>>;
+		pub Auctions get(fn auctions): map hasher(blake2_256) T::AuctionId => Option<AuctionInfo<T::AccountId, T::Balance, T::BlockNumber>>;
 		pub AuctionsIndex get(fn auctions_index): T::AuctionId;
-		pub AuctionEndTime get(fn auction_end_time): map(T::BlockNumber, Option<T::AuctionId>) => Option<AuctionIdLinkedItem<T>>;
+		pub AuctionEndTime get(fn auction_end_time): map hasher(blake2_256) (T::BlockNumber, Option<T::AuctionId>) => Option<AuctionIdLinkedItem<T>>;
 	}
 }
 
diff --git a/oracle/src/lib.rs b/oracle/src/lib.rs
index 8979c36d1ded4c5b8b0121bd7ed17b4156c346a4..ba1f79249cc7ad4840a613c247100a17cdef3928 100644
--- a/oracle/src/lib.rs
+++ b/oracle/src/lib.rs
@@ -33,9 +33,9 @@ pub trait Trait: frame_system::Trait {
 
 decl_storage! {
 	trait Store for Module<T: Trait> as Oracle {
-		pub RawValues get(raw_values): double_map T::OracleKey, T::AccountId => Option<TimestampedValueOf<T>>;
-		pub HasUpdate get(has_update): map T::OracleKey => bool;
-		pub Values get(values): map T::OracleKey => Option<TimestampedValueOf<T>>;
+		pub RawValues get(raw_values): double_map hasher(blake2_256) T::OracleKey, hasher(blake2_256) T::AccountId => Option<TimestampedValueOf<T>>;
+		pub HasUpdate get(has_update): map hasher(blake2_256) T::OracleKey => bool;
+		pub Values get(values): map hasher(blake2_256) T::OracleKey => Option<TimestampedValueOf<T>>;
 	}
 }
 
diff --git a/tokens/src/lib.rs b/tokens/src/lib.rs
index eaff2b16e6719e39dc7c7246290e3823750ec591..2db956a9fddd8882bc8bf09c7615b73d2380e28f 100644
--- a/tokens/src/lib.rs
+++ b/tokens/src/lib.rs
@@ -1,10 +1,7 @@
 #![cfg_attr(not(feature = "std"), no_std)]
 
 use frame_support::{decl_error, decl_event, decl_module, decl_storage, ensure, traits::Get, Parameter};
-use rstd::{
-	collections::btree_map::BTreeMap,
-	convert::{TryFrom, TryInto},
-};
+use rstd::convert::{TryFrom, TryInto};
 use sp_runtime::{
 	traits::{CheckedAdd, CheckedSub, MaybeSerializeDeserialize, Member, SimpleArithmetic, StaticLookup, Zero},
 	DispatchResult,
@@ -14,6 +11,9 @@ use sp_runtime::{
 // #3295 https://github.com/paritytech/substrate/issues/3295
 use frame_system::{self as system, ensure_signed};
 
+#[cfg(feature = "std")]
+use rstd::collections::btree_map::BTreeMap;
+
 use orml_traits::{
 	arithmetic::{self, Signed},
 	MultiCurrency, MultiCurrencyExtended, OnDustRemoval,
@@ -57,10 +57,10 @@ decl_storage! {
 				})
 				.into_iter()
 				.collect::<Vec<_>>()
-		}): map T::CurrencyId => T::Balance;
+		}): map hasher(blake2_256) T::CurrencyId => T::Balance;
 
 		/// The balance of a token type under an account.
-		pub Balance get(fn balance): double_map T::CurrencyId, T::AccountId => T::Balance;
+		pub Balance get(fn balance): double_map hasher(blake2_256) T::CurrencyId, hasher(blake2_256) T::AccountId => T::Balance;
 	}
 	add_extra_genesis {
 		config(endowed_accounts): Vec<(T::AccountId, T::CurrencyId, T::Balance)>;
diff --git a/utilities/src/linked_item.rs b/utilities/src/linked_item.rs
index 1bc376a8754193d10812aca78cb227f687ce69ff..9e8f3a849b77995e73f7e22222f4aeaa8512c784 100644
--- a/utilities/src/linked_item.rs
+++ b/utilities/src/linked_item.rs
@@ -172,7 +172,7 @@ mod tests {
 
 	decl_storage! {
 		trait Store for Module<T: Trait> as Test {
-			pub TestItem get(linked_list): map (Key, Option<Value>) => Option<TestLinkedItem>;
+			pub TestItem get(linked_list): map hasher(blake2_256) (Key, Option<Value>) => Option<TestLinkedItem>;
 		}
 	}
 
diff --git a/vesting/src/lib.rs b/vesting/src/lib.rs
index e3ea10ec4d5681c5cd447254e353b1ece7985fe9..395a4bb20e7f6c16eda9c643d59a7924c103b190 100644
--- a/vesting/src/lib.rs
+++ b/vesting/src/lib.rs
@@ -80,7 +80,7 @@ decl_storage! {
 					(who.clone(), vec![VestingSchedule {start, period, period_count, per_period}])
 				)
 				.collect::<Vec<_>>()
-		}): map T::AccountId => Vec<VestingScheduleOf<T>>;
+		}): map hasher(blake2_256) T::AccountId => Vec<VestingScheduleOf<T>>;
 	}
 
 	add_extra_genesis {