diff --git a/substrate/Cargo.lock b/substrate/Cargo.lock
index 356dbf4265370bfd0c837312ebc5fbcbc5498106..f570676f20e4733199de4522ccff7f08dba85498 100644
--- a/substrate/Cargo.lock
+++ b/substrate/Cargo.lock
@@ -534,11 +534,6 @@ name = "odds"
 version = "0.2.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "owning_ref"
-version = "0.2.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "owning_ref"
 version = "0.3.3"
@@ -557,16 +552,6 @@ dependencies = [
  "parking_lot 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "parking_lot"
-version = "0.3.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "owning_ref 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "parking_lot_core 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "thread-id 3.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "parking_lot"
 version = "0.4.8"
@@ -632,7 +617,7 @@ name = "polkadot-candidate-agreement"
 version = "0.1.0"
 dependencies = [
  "futures 0.1.17 (registry+https://github.com/rust-lang/crates.io-index)",
- "parking_lot 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "parking_lot 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "tokio-timer 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -984,16 +969,6 @@ dependencies = [
  "unicode-width 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "thread-id"
-version = "3.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
- "redox_syscall 0.1.31 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "thread_local"
 version = "0.3.4"
@@ -1226,10 +1201,8 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum num-traits 0.1.40 (registry+https://github.com/rust-lang/crates.io-index)" = "99843c856d68d8b4313b03a17e33c4bb42ae8f6610ea81b28abe076ac721b9b0"
 "checksum num_cpus 1.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "514f0d73e64be53ff320680ca671b64fe3fb91da01e1ae2ddc99eb51d453b20d"
 "checksum odds 0.2.25 (registry+https://github.com/rust-lang/crates.io-index)" = "c3df9b730298cea3a1c3faa90b7e2f9df3a9c400d0936d6015e6165734eefcba"
-"checksum owning_ref 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)" = "9d52571ddcb42e9c900c901a18d8d67e393df723fcd51dd59c5b1a85d0acb6cc"
 "checksum owning_ref 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "cdf84f41639e037b484f93433aa3897863b561ed65c6e59c7073d7c561710f37"
 "checksum parity-wasm 0.15.4 (registry+https://github.com/rust-lang/crates.io-index)" = "235801e9531998c4bb307f4ea6833c9f40a4cf132895219ac8c2cd25a9b310f7"
-"checksum parking_lot 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)" = "fa12d706797d42551663426a45e2db2e0364bd1dbf6aeada87e89c5f981f43e9"
 "checksum parking_lot 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)" = "149d8f5b97f3c1133e3cfcd8886449959e856b557ff281e292b733d7c69e005e"
 "checksum parking_lot_core 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "4f610cb9664da38e417ea3225f23051f589851999535290e077939838ab7a595"
 "checksum patricia-trie 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f1e2f638d79aba5c4a71a4f373df6e3cd702250a53b7f0ed4da1e2a7be9737ae"
@@ -1268,7 +1241,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum take 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b157868d8ac1f56b64604539990685fa7611d8fa9e5476cf0c02cf34d32917c5"
 "checksum termion 1.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "689a3bdfaab439fd92bc87df5c4c78417d3cbe537487274e9b0b2dce76e92096"
 "checksum textwrap 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c0b59b6b4b44d867f1370ef1bd91bfb262bf07bf0ae65c202ea2fbc16153b693"
-"checksum thread-id 3.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "2af4d6289a69a35c4d3aea737add39685f2784122c28119a7713165a63d68c9d"
 "checksum thread_local 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "1697c4b57aeeb7a536b647165a2825faddffb1d3bad386d507709bd51a90bb14"
 "checksum time 0.1.38 (registry+https://github.com/rust-lang/crates.io-index)" = "d5d788d3aa77bc0ef3e9621256885555368b47bd495c13dd2e7413c89f845520"
 "checksum tiny-keccak 1.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d52d12ad79e4063e0cb0ca5efa202ed7244b6ce4d25f4d3abe410b2a66128292"
diff --git a/substrate/candidate-agreement/Cargo.toml b/substrate/candidate-agreement/Cargo.toml
index 063a0809267628f8fd0da13c9e8a1da40ba05a08..83a8556ad302b67f0c5d22371dc267fe85667f0f 100644
--- a/substrate/candidate-agreement/Cargo.toml
+++ b/substrate/candidate-agreement/Cargo.toml
@@ -5,5 +5,5 @@ authors = ["Parity Technologies <admin@parity.io>"]
 
 [dependencies]
 futures = "0.1"
-parking_lot = "0.3"
+parking_lot = "0.4"
 tokio-timer = "0.1.2"