diff --git a/substrate/.gitlab-ci.yml b/substrate/.gitlab-ci.yml
index 99b354a60b..d3c9951df4 100644
--- a/substrate/.gitlab-ci.yml
+++ b/substrate/.gitlab-ci.yml
@@ -137,10 +137,14 @@ check-web-wasm:
     - time cargo web build -p sr-io
     - time cargo web build -p sr-primitives
     - time cargo web build -p sr-std
+    - time cargo web build -p substrate-client
+    - time cargo web build -p substrate-consensus-aura
+    - time cargo web build -p substrate-consensus-babe
     - time cargo web build -p substrate-consensus-common
     - time cargo web build -p substrate-keyring
     - time cargo web build -p substrate-keystore
     - time cargo web build -p substrate-executor
+    - time cargo web build -p substrate-network
     - time cargo web build -p substrate-network-libp2p
     - time cargo web build -p substrate-panic-handler
     - time cargo web build -p substrate-peerset
diff --git a/substrate/Cargo.lock b/substrate/Cargo.lock
index 7e92564208..738ccb6694 100644
--- a/substrate/Cargo.lock
+++ b/substrate/Cargo.lock
@@ -4068,6 +4068,7 @@ dependencies = [
  "substrate-telemetry 2.0.0",
  "substrate-test-client 2.0.0",
  "tokio 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
+ "tokio-timer 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -4125,6 +4126,7 @@ dependencies = [
  "substrate-telemetry 2.0.0",
  "substrate-test-client 2.0.0",
  "tokio 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
+ "tokio-timer 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -4196,7 +4198,7 @@ dependencies = [
  "substrate-inherents 2.0.0",
  "substrate-primitives 2.0.0",
  "substrate-test-client 2.0.0",
- "tokio 0.1.21 (registry+https://github.com/rust-lang/crates.io-index)",
+ "tokio-timer 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
diff --git a/substrate/core/consensus/aura/Cargo.toml b/substrate/core/consensus/aura/Cargo.toml
index 446dcbff3a..9c46b942a4 100644
--- a/substrate/core/consensus/aura/Cargo.toml
+++ b/substrate/core/consensus/aura/Cargo.toml
@@ -22,7 +22,7 @@ consensus_common = { package = "substrate-consensus-common", path = "../common"
 authorities = { package = "substrate-consensus-authorities", path = "../authorities" }
 runtime_primitives = { package = "sr-primitives", path = "../../sr-primitives" }
 futures = "0.1.17"
-tokio = "0.1.7"
+tokio-timer = "0.2.11"
 parking_lot = "0.8.0"
 log = "0.4"
 
@@ -32,4 +32,5 @@ substrate-executor = { path = "../../executor" }
 network = { package = "substrate-network", path = "../../network", features = ["test-helpers"]}
 service = { package = "substrate-service", path = "../../service" }
 test_client = { package = "substrate-test-client", path = "../../test-client" }
+tokio = "0.1.7"
 env_logger = "0.6"
diff --git a/substrate/core/consensus/aura/src/lib.rs b/substrate/core/consensus/aura/src/lib.rs
index e3fffad33f..ad618c2188 100644
--- a/substrate/core/consensus/aura/src/lib.rs
+++ b/substrate/core/consensus/aura/src/lib.rs
@@ -56,7 +56,7 @@ use inherents::{InherentDataProviders, InherentData};
 use authorities::AuthoritiesApi;
 
 use futures::{Future, IntoFuture, future};
-use tokio::timer::Timeout;
+use tokio_timer::Timeout;
 use log::{error, warn, debug, info, trace};
 
 use srml_aura::{
@@ -914,7 +914,7 @@ mod tests {
 			.map(|_| ())
 			.map_err(|_| ());
 
-		let drive_to_completion = ::tokio::timer::Interval::new_interval(TEST_ROUTING_INTERVAL)
+		let drive_to_completion = ::tokio_timer::Interval::new_interval(TEST_ROUTING_INTERVAL)
 			.for_each(move |_| {
 				net.lock().send_import_notifications();
 				net.lock().sync_without_disconnects();
diff --git a/substrate/core/consensus/babe/Cargo.toml b/substrate/core/consensus/babe/Cargo.toml
index 04cd42c680..020497a104 100644
--- a/substrate/core/consensus/babe/Cargo.toml
+++ b/substrate/core/consensus/babe/Cargo.toml
@@ -23,7 +23,7 @@ authorities = { package = "substrate-consensus-authorities", path = "../authorit
 slots = { package = "substrate-consensus-slots", path = "../slots"  }
 runtime_primitives = { package = "sr-primitives", path = "../../sr-primitives" }
 futures = "0.1.26"
-tokio = "0.1.18"
+tokio-timer = "0.2.11"
 parking_lot = "0.8.0"
 log = "0.4.6"
 schnorrkel = "0.1.1"
@@ -36,4 +36,5 @@ substrate-executor = { path = "../../executor" }
 network = { package = "substrate-network", path = "../../network", features = ["test-helpers"]}
 service = { package = "substrate-service", path = "../../service" }
 test_client = { package = "substrate-test-client", path = "../../test-client" }
+tokio = "0.1.18"
 env_logger = "0.6.1"
diff --git a/substrate/core/consensus/babe/src/lib.rs b/substrate/core/consensus/babe/src/lib.rs
index c66eb68137..f28c23de54 100644
--- a/substrate/core/consensus/babe/src/lib.rs
+++ b/substrate/core/consensus/babe/src/lib.rs
@@ -79,7 +79,7 @@ use client::{
 };
 use slots::{CheckedHeader, check_equivocation};
 use futures::{Future, IntoFuture, future};
-use tokio::timer::Timeout;
+use tokio_timer::Timeout;
 use log::{error, warn, debug, info, trace};
 
 use slots::{SlotWorker, SlotData, SlotInfo, SlotCompatible, slot_now};
@@ -984,7 +984,7 @@ mod tests {
 			.map(drop)
 			.map_err(drop);
 
-		let drive_to_completion = ::tokio::timer::Interval::new_interval(TEST_ROUTING_INTERVAL)
+		let drive_to_completion = ::tokio_timer::Interval::new_interval(TEST_ROUTING_INTERVAL)
 			.for_each(move |_| {
 				net.lock().send_import_notifications();
 				net.lock().sync_without_disconnects();
diff --git a/substrate/core/consensus/slots/Cargo.toml b/substrate/core/consensus/slots/Cargo.toml
index 7a3b487dc6..b82c2fc9d7 100644
--- a/substrate/core/consensus/slots/Cargo.toml
+++ b/substrate/core/consensus/slots/Cargo.toml
@@ -13,7 +13,7 @@ runtime_primitives = { package = "sr-primitives", path = "../../sr-primitives" }
 consensus_common = { package = "substrate-consensus-common", path = "../common" }
 inherents = { package = "substrate-inherents", path = "../../inherents" }
 futures = "0.1.17"
-tokio = "0.1.7"
+tokio-timer = "0.2.11"
 parking_lot = "0.8.0"
 log = "0.4"
 
diff --git a/substrate/core/consensus/slots/src/lib.rs b/substrate/core/consensus/slots/src/lib.rs
index aee398a9ce..18ec2451be 100644
--- a/substrate/core/consensus/slots/src/lib.rs
+++ b/substrate/core/consensus/slots/src/lib.rs
@@ -41,8 +41,6 @@ use runtime_primitives::generic::BlockId;
 use runtime_primitives::traits::{ApiRef, Block, ProvideRuntimeApi};
 use std::fmt::Debug;
 use std::ops::Deref;
-use std::sync::mpsc;
-use std::thread;
 
 /// A worker that should be invoked at every new slot.
 pub trait SlotWorker<B: Block> {
@@ -66,58 +64,6 @@ pub trait SlotCompatible {
 	) -> Result<(u64, u64), consensus_common::Error>;
 }
 
-/// Start a new slot worker in a separate thread.
-#[deprecated(since = "1.1", note = "Please spawn a thread manually")]
-pub fn start_slot_worker_thread<B, C, W, SO, SC, T, OnExit>(
-	slot_duration: SlotDuration<T>,
-	select_chain: C,
-	worker: W,
-	sync_oracle: SO,
-	on_exit: OnExit,
-	inherent_data_providers: InherentDataProviders,
-) -> Result<(), consensus_common::Error>
-where
-	B: Block + 'static,
-	C: SelectChain<B> + Clone + 'static,
-	W: SlotWorker<B> + Send + Sync + 'static,
-	SO: SyncOracle + Send + Clone + 'static,
-	SC: SlotCompatible + 'static,
-	OnExit: Future<Item = (), Error = ()> + Send + 'static,
-	T: SlotData + Send + Clone + 'static,
-{
-	use tokio::runtime::current_thread::Runtime;
-
-	let (result_sender, result_recv) = mpsc::channel();
-
-	thread::spawn(move || {
-		let mut runtime = match Runtime::new() {
-			Ok(r) => r,
-			Err(e) => {
-				warn!(target: "slots", "Unable to start authorship: {:?}", e);
-				return;
-			}
-		};
-
-		let slot_worker_future = start_slot_worker::<_, _, _, T, _, SC>(
-			slot_duration.clone(),
-			select_chain,
-			worker,
-			sync_oracle,
-			inherent_data_providers,
-		);
-
-		result_sender
-			.send(Ok(()))
-			.expect("Receive is not dropped before receiving a result; qed");
-
-		let _ = runtime.block_on(slot_worker_future.select(on_exit).map(|_| ()));
-	});
-
-	result_recv
-		.recv()
-		.expect("Slots start thread result sender dropped")
-}
-
 /// Start a new slot worker.
 ///
 /// Every time a new slot is triggered, `worker.on_slot` is called and the future it returns is
diff --git a/substrate/core/consensus/slots/src/slots.rs b/substrate/core/consensus/slots/src/slots.rs
index 964eeaff29..a848a96762 100644
--- a/substrate/core/consensus/slots/src/slots.rs
+++ b/substrate/core/consensus/slots/src/slots.rs
@@ -26,7 +26,7 @@ use inherents::{InherentData, InherentDataProviders};
 use log::warn;
 use std::marker::PhantomData;
 use std::time::{Duration, Instant};
-use tokio::timer::Delay;
+use tokio_timer::Delay;
 
 /// Returns current duration since unix epoch.
 pub fn duration_now() -> Option<Duration> {
diff --git a/substrate/core/test-runtime/wasm/Cargo.lock b/substrate/core/test-runtime/wasm/Cargo.lock
index be1e3ab84f..19c6b36ebc 100644
--- a/substrate/core/test-runtime/wasm/Cargo.lock
+++ b/substrate/core/test-runtime/wasm/Cargo.lock
@@ -2561,7 +2561,7 @@ dependencies = [
  "substrate-consensus-common 2.0.0",
  "substrate-inherents 2.0.0",
  "substrate-primitives 2.0.0",
- "tokio 0.1.20 (registry+https://github.com/rust-lang/crates.io-index)",
+ "tokio-timer 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]