diff --git a/substrate/core/sr-std/src/lib.rs b/substrate/core/sr-std/src/lib.rs
index 416c91bc7f..416dbf6be9 100644
--- a/substrate/core/sr-std/src/lib.rs
+++ b/substrate/core/sr-std/src/lib.rs
@@ -45,4 +45,9 @@ pub mod prelude {
 	pub use ::boxed::Box;
 	pub use ::cmp::{Eq, PartialEq};
 	pub use ::clone::Clone;
+
+	// Re-export `vec!` macro here, but not in `std` mode, since
+	// std's prelude already brings `vec!` into the scope.
+	#[cfg(not(feature = "std"))]
+	pub use ::vec;
 }
diff --git a/substrate/srml/contract/Cargo.toml b/substrate/srml/contract/Cargo.toml
index 2a265cb0fa..f926bd9163 100644
--- a/substrate/srml/contract/Cargo.toml
+++ b/substrate/srml/contract/Cargo.toml
@@ -2,6 +2,7 @@
 name = "srml-contract"
 version = "0.1.0"
 authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2018"
 
 [dependencies]
 serde = { version = "1.0", default-features = false }
@@ -10,13 +11,13 @@ parity-codec = { version = "2.2", default-features = false }
 parity-codec-derive = { version = "2.1", default-features = false }
 parity-wasm = { version = "0.31", default-features = false }
 substrate-primitives = { path = "../../core/primitives", default-features = false }
-sr-primitives = { path = "../../core/sr-primitives", default-features = false }
-sr-io = { path = "../../core/sr-io", default-features = false }
-sr-std = { path = "../../core/sr-std", default-features = false }
-sr-sandbox = { path = "../../core/sr-sandbox", default-features = false }
+runtime-primitives = { package = "sr-primitives", path = "../../core/sr-primitives", default-features = false }
+runtime-io = { package = "sr-io", path = "../../core/sr-io", default-features = false }
+rstd = { package = "sr-std", path = "../../core/sr-std", default-features = false }
+sandbox = { package = "sr-sandbox", path = "../../core/sr-sandbox", default-features = false }
 srml-support = { path = "../support", default-features = false }
-srml-system = { path = "../system", default-features = false }
-srml-balances = { path = "../balances", default-features = false }
+system = { package = "srml-system", path = "../system", default-features = false }
+balances = { package = "srml-balances", path = "../balances", default-features = false }
 
 [dev-dependencies]
 wabt = "~0.7.4"
@@ -30,13 +31,13 @@ std = [
 	"parity-codec/std",
 	"parity-codec-derive/std",
 	"substrate-primitives/std",
-	"sr-primitives/std",
-	"sr-io/std",
-	"sr-std/std",
-	"srml-balances/std",
-	"sr-sandbox/std",
+	"runtime-primitives/std",
+	"runtime-io/std",
+	"rstd/std",
+	"balances/std",
+	"sandbox/std",
 	"srml-support/std",
-	"srml-system/std",
+	"system/std",
 	"parity-wasm/std",
 	"pwasm-utils/std",
 ]
diff --git a/substrate/srml/contract/src/account_db.rs b/substrate/srml/contract/src/account_db.rs
index 6142abcbe2..bac3b547d2 100644
--- a/substrate/srml/contract/src/account_db.rs
+++ b/substrate/srml/contract/src/account_db.rs
@@ -17,11 +17,11 @@
 //! Auxilliaries to help with managing partial changes to accounts state.
 
 use super::{CodeHash, CodeHashOf, StorageOf, Trait};
+use {balances, system};
 use rstd::cell::RefCell;
 use rstd::collections::btree_map::{BTreeMap, Entry};
 use rstd::prelude::*;
 use runtime_support::{StorageMap, StorageDoubleMap};
-use {balances, system};
 
 pub struct ChangeEntry<T: Trait> {
 	balance: Option<T::Balance>,
diff --git a/substrate/srml/contract/src/exec.rs b/substrate/srml/contract/src/exec.rs
index 44dacb2799..a4024f439a 100644
--- a/substrate/srml/contract/src/exec.rs
+++ b/substrate/srml/contract/src/exec.rs
@@ -15,8 +15,8 @@
 // along with Substrate. If not, see <http://www.gnu.org/licenses/>.
 
 use super::{CodeHash, Config, ContractAddressFor, Event, RawEvent, Trait};
-use account_db::{AccountDb, DirectAccountDb, OverlayAccountDb};
-use gas::{GasMeter, Token, approx_gas_for_balance};
+use crate::account_db::{AccountDb, DirectAccountDb, OverlayAccountDb};
+use crate::gas::{GasMeter, Token, approx_gas_for_balance};
 
 use balances::{self, EnsureAccountLiquid};
 use rstd::prelude::*;
@@ -285,8 +285,10 @@ where
 		let mut output_data = Vec::new();
 
 		let (change_set, events, calls) = {
-			let mut overlay = OverlayAccountDb::new(&self.overlay);
-			let mut nested = self.nested(overlay, dest.clone());
+			let mut nested = self.nested(
+				OverlayAccountDb::new(&self.overlay),
+				dest.clone()
+			);
 
 			if value > T::Balance::zero() {
 				transfer(
@@ -608,15 +610,16 @@ mod tests {
 		ExecFeeToken, ExecutionContext, Ext, Loader, EmptyOutputBuf, TransferFeeKind, TransferFeeToken,
 		Vm, VmExecResult, InstantiateReceipt, RawEvent,
 	};
-	use account_db::AccountDb;
-	use gas::GasMeter;
+	use crate::account_db::AccountDb;
+	use crate::gas::GasMeter;
+	use crate::tests::{ExtBuilder, Test};
+	use crate::{CodeHash, Config};
 	use runtime_io::with_externalities;
 	use std::cell::RefCell;
 	use std::collections::HashMap;
 	use std::marker::PhantomData;
 	use std::rc::Rc;
-	use tests::{ExtBuilder, Test};
-	use {CodeHash, Config};
+	use assert_matches::assert_matches;
 
 	const ALICE: u64 = 1;
 	const BOB: u64 = 2;
diff --git a/substrate/srml/contract/src/gas.rs b/substrate/srml/contract/src/gas.rs
index 61e915672d..35f3c4d7cd 100644
--- a/substrate/srml/contract/src/gas.rs
+++ b/substrate/srml/contract/src/gas.rs
@@ -14,10 +14,10 @@
 // You should have received a copy of the GNU General Public License
 // along with Substrate. If not, see <http://www.gnu.org/licenses/>.
 
+use crate::{GasSpent, Module, Trait};
 use balances;
 use runtime_primitives::traits::{As, CheckedMul, CheckedSub, Zero};
 use runtime_support::StorageValue;
-use {GasSpent, Module, Trait};
 
 #[cfg(test)]
 use std::{any::Any, fmt::Debug};
@@ -295,7 +295,7 @@ macro_rules! match_tokens {
 #[cfg(test)]
 mod tests {
 	use super::{GasMeter, Token};
-	use tests::Test;
+	use crate::tests::Test;
 
 	/// A trivial token that charges 1 unit of gas.
 	#[derive(Copy, Clone, PartialEq, Eq, Debug)]
diff --git a/substrate/srml/contract/src/lib.rs b/substrate/srml/contract/src/lib.rs
index 38b2aa3e75..f391f8ce5f 100644
--- a/substrate/srml/contract/src/lib.rs
+++ b/substrate/srml/contract/src/lib.rs
@@ -52,41 +52,14 @@
 
 #![cfg_attr(not(feature = "std"), no_std)]
 
+// We need these `extern crate` to be placed here otherwise there will be errors.
+// TODO: https://github.com/paritytech/substrate/issues/1509
 #[macro_use]
 extern crate parity_codec_derive;
-
-extern crate parity_wasm;
-extern crate pwasm_utils;
-
 extern crate parity_codec as codec;
-extern crate sr_io as runtime_io;
-extern crate sr_sandbox as sandbox;
-
-#[cfg_attr(not(feature = "std"), macro_use)]
-extern crate sr_std as rstd;
-
-extern crate srml_balances as balances;
-extern crate srml_system as system;
-
 #[macro_use]
 extern crate srml_support as runtime_support;
 
-extern crate sr_primitives as runtime_primitives;
-
-#[cfg(test)]
-extern crate substrate_primitives;
-
-#[cfg(test)]
-#[macro_use]
-extern crate assert_matches;
-
-#[cfg(test)]
-extern crate wabt;
-
-#[cfg(test)]
-#[macro_use]
-extern crate hex_literal;
-
 #[macro_use]
 mod gas;
 
@@ -97,8 +70,8 @@ mod wasm;
 #[cfg(test)]
 mod tests;
 
-use exec::ExecutionContext;
-use account_db::AccountDb;
+use crate::exec::ExecutionContext;
+use crate::account_db::AccountDb;
 
 use rstd::prelude::*;
 use rstd::marker::PhantomData;
@@ -234,8 +207,8 @@ decl_module! {
 			let mut gas_meter = gas::buy_gas::<T>(&origin, gas_limit)?;
 
 			let cfg = Config::preload();
-			let vm = ::wasm::WasmVm::new(&cfg.schedule);
-			let loader = ::wasm::WasmLoader::new(&cfg.schedule);
+			let vm = crate::wasm::WasmVm::new(&cfg.schedule);
+			let loader = crate::wasm::WasmLoader::new(&cfg.schedule);
 			let mut ctx = ExecutionContext::top_level(origin.clone(), &cfg, &vm, &loader);
 
 			let result = ctx.call(dest, value, &mut gas_meter, &data, exec::EmptyOutputBuf::new());
@@ -288,8 +261,8 @@ decl_module! {
 			let mut gas_meter = gas::buy_gas::<T>(&origin, gas_limit)?;
 
 			let cfg = Config::preload();
-			let vm = ::wasm::WasmVm::new(&cfg.schedule);
-			let loader = ::wasm::WasmLoader::new(&cfg.schedule);
+			let vm = crate::wasm::WasmVm::new(&cfg.schedule);
+			let loader = crate::wasm::WasmLoader::new(&cfg.schedule);
 			let mut ctx = ExecutionContext::top_level(origin.clone(), &cfg, &vm, &loader);
 			let result = ctx.instantiate(endowment, &mut gas_meter, &code_hash, &data);
 
@@ -380,7 +353,7 @@ decl_storage! {
 /// The storage items associated with an account/key.
 ///
 /// TODO: keys should also be able to take AsRef<KeyType> to ensure Vec<u8>s can be passed as &[u8]
-pub(crate) struct StorageOf<T>(::rstd::marker::PhantomData<T>);
+pub(crate) struct StorageOf<T>(rstd::marker::PhantomData<T>);
 impl<T: Trait> StorageDoubleMap for StorageOf<T> {
 	const PREFIX: &'static [u8] = b"con:sto:";
 	type Key1 = T::AccountId;
diff --git a/substrate/srml/contract/src/tests.rs b/substrate/srml/contract/src/tests.rs
index d843c993c3..eee12b0ac1 100644
--- a/substrate/srml/contract/src/tests.rs
+++ b/substrate/srml/contract/src/tests.rs
@@ -23,13 +23,16 @@ use runtime_io::with_externalities;
 use runtime_primitives::testing::{Digest, DigestItem, H256, Header};
 use runtime_primitives::traits::{BlakeTwo256, IdentityLookup};
 use runtime_primitives::BuildStorage;
+use runtime_io;
 use runtime_support::{StorageMap, StorageDoubleMap};
 use substrate_primitives::{Blake2Hasher};
-use system::{ensure_signed, Phase, EventRecord};
-use wabt;
-use {
-	balances, runtime_io, system, ComputeDispatchFee, ContractAddressFor, GenesisConfig, Module, RawEvent, StorageOf,
-	Trait
+use system::{self, Phase, EventRecord};
+use {wabt, balances};
+use hex_literal::*;
+use assert_matches::assert_matches;
+use crate::{
+	ContractAddressFor, GenesisConfig, Module, RawEvent, StorageOf,
+	Trait, ComputeDispatchFee
 };
 
 mod contract {
diff --git a/substrate/srml/contract/src/wasm/code_cache.rs b/substrate/srml/contract/src/wasm/code_cache.rs
index e0c5bd4b97..c95bbee4c2 100644
--- a/substrate/srml/contract/src/wasm/code_cache.rs
+++ b/substrate/srml/contract/src/wasm/code_cache.rs
@@ -25,12 +25,12 @@
 //! this guarantees that every instrumented contract code in cache cannot have the version equal to the current one.
 //! Thus, before executing a contract it should be reinstrument with new schedule.
 
-use gas::{GasMeter, Token};
+use crate::gas::{GasMeter, Token};
+use crate::wasm::{prepare, runtime::Env, PrefabWasmModule};
+use crate::{CodeHash, CodeStorage, PristineCode, Schedule, Trait};
 use rstd::prelude::*;
 use runtime_primitives::traits::{As, CheckedMul, Hash, Bounded};
 use runtime_support::StorageMap;
-use wasm::{prepare, runtime::Env, PrefabWasmModule};
-use {CodeHash, CodeStorage, PristineCode, Schedule, Trait};
 
 /// Gas metering token that used for charging storing code into the code storage.
 ///
diff --git a/substrate/srml/contract/src/wasm/env_def/macros.rs b/substrate/srml/contract/src/wasm/env_def/macros.rs
index bd123c4360..27485d55ce 100644
--- a/substrate/srml/contract/src/wasm/env_def/macros.rs
+++ b/substrate/srml/contract/src/wasm/env_def/macros.rs
@@ -29,13 +29,13 @@ macro_rules! convert_args {
 macro_rules! gen_signature {
 	( ( $( $params: ty ),* ) ) => (
 		{
-			$crate::parity_wasm::elements::FunctionType::new(convert_args!($($params),*), None)
+			parity_wasm::elements::FunctionType::new(convert_args!($($params),*), None)
 		}
 	);
 
 	( ( $( $params: ty ),* ) -> $returns: ty ) => (
 		{
-			$crate::parity_wasm::elements::FunctionType::new(convert_args!($($params),*), Some({
+			parity_wasm::elements::FunctionType::new(convert_args!($($params),*), Some({
 				use $crate::wasm::env_def::ConvertibleToWasm; <$returns>::VALUE_TYPE
 			}))
 		}
@@ -96,7 +96,7 @@ macro_rules! unmarshall_then_body {
 #[inline(always)]
 pub fn constrain_closure<R, F>(f: F) -> F
 where
-	F: FnOnce() -> Result<R, ::sandbox::HostError>,
+	F: FnOnce() -> Result<R, sandbox::HostError>,
 {
 	f
 }
@@ -110,14 +110,14 @@ macro_rules! unmarshall_then_body_then_marshall {
 			unmarshall_then_body!($body, $ctx, $args_iter, $( $names : $params ),*)
 		});
 		let r = body()?;
-		return Ok($crate::sandbox::ReturnValue::Value({ use $crate::wasm::env_def::ConvertibleToWasm; r.to_typed_value() }))
+		return Ok(sandbox::ReturnValue::Value({ use $crate::wasm::env_def::ConvertibleToWasm; r.to_typed_value() }))
 	});
 	( $args_iter:ident, $ctx:ident, ( $( $names:ident : $params:ty ),* ) => $body:tt ) => ({
 		let body = $crate::wasm::env_def::macros::constrain_closure::<(), _>(|| {
 			unmarshall_then_body!($body, $ctx, $args_iter, $( $names : $params ),*)
 		});
 		body()?;
-		return Ok($crate::sandbox::ReturnValue::Unit)
+		return Ok(sandbox::ReturnValue::Unit)
 	})
 }
 
@@ -126,7 +126,7 @@ macro_rules! define_func {
 	( < E: $ext_ty:tt > $name:ident ( $ctx: ident $(, $names:ident : $params:ty)*) $(-> $returns:ty)* => $body:tt ) => {
 		fn $name< E: $ext_ty >(
 			$ctx: &mut $crate::wasm::Runtime<E>,
-			args: &[$crate::sandbox::TypedValue],
+			args: &[sandbox::TypedValue],
 		) -> Result<sandbox::ReturnValue, sandbox::HostError> {
 			#[allow(unused)]
 			let mut args = args.iter();
@@ -176,7 +176,7 @@ macro_rules! define_env {
 		pub struct $init_name;
 
 		impl $crate::wasm::env_def::ImportSatisfyCheck for $init_name {
-			fn can_satisfy(name: &[u8], func_type: &$crate::parity_wasm::elements::FunctionType) -> bool {
+			fn can_satisfy(name: &[u8], func_type: &parity_wasm::elements::FunctionType) -> bool {
 				gen_signature_dispatch!( name, func_type ; $( $name ( $ctx $(, $names : $params )* ) $( -> $returns )* , )* );
 
 				return false;
@@ -197,10 +197,10 @@ mod tests {
 	use parity_wasm::elements::ValueType;
 	use runtime_primitives::traits::{As, Zero};
 	use sandbox::{self, ReturnValue, TypedValue};
-	use wasm::tests::MockExt;
-	use wasm::Runtime;
-	use exec::Ext;
-	use Trait;
+	use crate::wasm::tests::MockExt;
+	use crate::wasm::Runtime;
+	use crate::exec::Ext;
+	use crate::Trait;
 
 	#[test]
 	fn macro_unmarshall_then_body_then_marshall_value_or_trap() {
@@ -304,7 +304,7 @@ mod tests {
 
 	#[test]
 	fn macro_define_env() {
-		use wasm::env_def::ImportSatisfyCheck;
+		use crate::wasm::env_def::ImportSatisfyCheck;
 
 		define_env!(Env, <E: Ext>,
 			ext_gas( _ctx, amount: u32 ) => {
diff --git a/substrate/srml/contract/src/wasm/env_def/mod.rs b/substrate/srml/contract/src/wasm/env_def/mod.rs
index 0f4de91860..65e9e14e67 100644
--- a/substrate/srml/contract/src/wasm/env_def/mod.rs
+++ b/substrate/srml/contract/src/wasm/env_def/mod.rs
@@ -15,9 +15,10 @@
 // along with Substrate. If not, see <http://www.gnu.org/licenses/>.
 
 use super::Runtime;
-use exec::Ext;
-use parity_wasm::elements::{FunctionType, ValueType};
+use crate::exec::Ext;
+
 use sandbox::{self, TypedValue};
+use parity_wasm::elements::{FunctionType, ValueType};
 
 #[macro_use]
 pub(crate) mod macros;
@@ -26,7 +27,7 @@ pub trait ConvertibleToWasm: Sized {
 	const VALUE_TYPE: ValueType;
 	type NativeType;
 	fn to_typed_value(self) -> TypedValue;
-	fn from_typed_value(TypedValue) -> Option<Self>;
+	fn from_typed_value(_: TypedValue) -> Option<Self>;
 }
 impl ConvertibleToWasm for i32 {
 	type NativeType = i32;
diff --git a/substrate/srml/contract/src/wasm/mod.rs b/substrate/srml/contract/src/wasm/mod.rs
index 4d75b8a7d1..aba320db38 100644
--- a/substrate/srml/contract/src/wasm/mod.rs
+++ b/substrate/srml/contract/src/wasm/mod.rs
@@ -17,13 +17,14 @@
 //! This module provides a means for executing contracts
 //! represented in wasm.
 
-use codec::Compact;
-use exec::{Ext, EmptyOutputBuf, VmExecResult};
-use gas::GasMeter;
+use crate::{CodeHash, Schedule, Trait};
+use crate::wasm::env_def::FunctionImplProvider;
+use crate::exec::{Ext, EmptyOutputBuf, VmExecResult};
+use crate::gas::GasMeter;
+
 use rstd::prelude::*;
 use sandbox;
-use wasm::env_def::FunctionImplProvider;
-use {CodeHash, Schedule, Trait};
+
 
 #[macro_use]
 mod env_def;
@@ -72,7 +73,7 @@ impl<'a, T: Trait> WasmLoader<'a, T> {
 	}
 }
 
-impl<'a, T: Trait> ::exec::Loader<T> for WasmLoader<'a, T> {
+impl<'a, T: Trait> crate::exec::Loader<T> for WasmLoader<'a, T> {
 	type Executable = WasmExecutable;
 
 	fn load_init(&self, code_hash: &CodeHash<T>) -> Result<WasmExecutable, &'static str> {
@@ -102,7 +103,7 @@ impl<'a, T: Trait> WasmVm<'a, T> {
 	}
 }
 
-impl<'a, T: Trait> ::exec::Vm<T> for WasmVm<'a, T> {
+impl<'a, T: Trait> crate::exec::Vm<T> for WasmVm<'a, T> {
 	type Executable = WasmExecutable;
 
 	fn execute<E: Ext<T = T>>(
@@ -173,13 +174,12 @@ mod tests {
 	use super::*;
 	use std::collections::HashMap;
 	use substrate_primitives::H256;
-	use exec::{CallReceipt, Ext, InstantiateReceipt, EmptyOutputBuf};
-	use balances;
-	use gas::GasMeter;
-	use tests::{Test, Call};
+	use crate::exec::{CallReceipt, Ext, InstantiateReceipt, EmptyOutputBuf};
+	use crate::gas::GasMeter;
+	use crate::tests::{Test, Call};
 	use wabt;
-	use wasm::prepare::prepare_contract;
-	use CodeHash;
+	use crate::wasm::prepare::prepare_contract;
+	use crate::CodeHash;
 
 	#[derive(Debug, PartialEq, Eq)]
 	struct DispatchEntry(Call);
@@ -276,10 +276,10 @@ mod tests {
 		ext: &mut E,
 		gas_meter: &mut GasMeter<E::T>,
 	) -> Result<(), &'static str> {
-		use exec::Vm;
+		use crate::exec::Vm;
 
 		let wasm = wabt::wat2wasm(wat).unwrap();
-		let schedule = ::Schedule::<u64>::default();
+		let schedule = crate::Schedule::<u64>::default();
 		let prefab_module =
 			prepare_contract::<Test, super::runtime::Env>(&wasm, &schedule).unwrap();
 
diff --git a/substrate/srml/contract/src/wasm/prepare.rs b/substrate/srml/contract/src/wasm/prepare.rs
index 9d401a6a7c..12f4c7d283 100644
--- a/substrate/srml/contract/src/wasm/prepare.rs
+++ b/substrate/srml/contract/src/wasm/prepare.rs
@@ -18,14 +18,15 @@
 //! wasm module before execution. It also extracts some essential information
 //! from a module.
 
+use crate::wasm::env_def::ImportSatisfyCheck;
+use crate::wasm::PrefabWasmModule;
+use crate::{Schedule, Trait};
+
 use parity_wasm::elements::{self, Internal, External, MemoryType, Type};
 use pwasm_utils;
 use pwasm_utils::rules;
 use rstd::prelude::*;
 use runtime_primitives::traits::As;
-use wasm::env_def::ImportSatisfyCheck;
-use wasm::PrefabWasmModule;
-use {Schedule, Trait};
 
 struct ContractModule<'a, Gas: 'a> {
 	// An `Option` is used here for loaning (`take()`-ing) the module.
@@ -316,10 +317,11 @@ pub fn prepare_contract<T: Trait, C: ImportSatisfyCheck>(
 #[cfg(test)]
 mod tests {
 	use super::*;
+	use crate::tests::Test;
+	use crate::exec::Ext;
 	use std::fmt;
-	use tests::Test;
-	use exec::Ext;
 	use wabt;
+	use assert_matches::assert_matches;
 
 	impl fmt::Debug for PrefabWasmModule {
 		fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
diff --git a/substrate/srml/contract/src/wasm/runtime.rs b/substrate/srml/contract/src/wasm/runtime.rs
index ce1bf89baa..f18e5162b3 100644
--- a/substrate/srml/contract/src/wasm/runtime.rs
+++ b/substrate/srml/contract/src/wasm/runtime.rs
@@ -16,16 +16,15 @@
 
 //! Environment definition of the wasm smart-contract runtime.
 
-use super::{Schedule};
-use exec::{Ext, BalanceOf, VmExecResult, OutputBuf, EmptyOutputBuf, CallReceipt, InstantiateReceipt};
+use crate::{Schedule, Trait, CodeHash, ComputeDispatchFee};
+use crate::exec::{Ext, BalanceOf, VmExecResult, OutputBuf, EmptyOutputBuf, CallReceipt, InstantiateReceipt};
+use crate::gas::{GasMeter, Token, GasMeterResult, approx_gas_for_balance};
+use sandbox;
+use system;
 use rstd::prelude::*;
 use rstd::mem;
 use codec::{Decode, Encode};
-use gas::{GasMeter, Token, GasMeterResult, approx_gas_for_balance};
 use runtime_primitives::traits::{As, CheckedMul, Bounded};
-use sandbox;
-use system;
-use {Trait, CodeHash, ComputeDispatchFee};
 
 /// Enumerates all possible *special* trap conditions.
 ///