diff --git a/Cargo.lock b/Cargo.lock
index 5dee3672..88e2ad5b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4884,9 +4884,9 @@ checksum = "cda74da7e1a664f795bb1f8a87ec406fb89a02522cf6e50620d016add6dbbf5c"
 
 [[package]]
 name = "tokio"
-version = "1.21.1"
+version = "1.21.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0020c875007ad96677dcc890298f4b942882c5d4eb7cc8f439fc3bf813dc9c95"
+checksum = "a9e03c497dc955702ba729190dc4aac6f2a0ce97f913e5b1b5912fc5039d9099"
 dependencies = [
  "autocfg 1.1.0",
  "bytes",
@@ -4894,7 +4894,6 @@ dependencies = [
  "memchr",
  "mio",
  "num_cpus",
- "once_cell",
  "parking_lot 0.12.0",
  "pin-project-lite",
  "signal-hook-registry",
diff --git a/tower-batch/Cargo.toml b/tower-batch/Cargo.toml
index b0eb6512..08b3bf7b 100644
--- a/tower-batch/Cargo.toml
+++ b/tower-batch/Cargo.toml
@@ -10,7 +10,7 @@ futures = "0.3.24"
 futures-core = "0.3.24"
 pin-project = "1.0.12"
 rayon = "1.5.3"
-tokio = { version = "1.21.1", features = ["time", "sync", "tracing", "macros"] }
+tokio = { version = "1.21.2", features = ["time", "sync", "tracing", "macros"] }
 tokio-util = "0.7.4"
 tower = { version = "0.4.13", features = ["util", "buffer"] }
 tracing = "0.1.36"
@@ -25,7 +25,7 @@ tinyvec = { version = "1.6.0", features = ["rustc_1_55"] }
 ed25519-zebra = "3.0.0"
 rand = { version = "0.8.5", package = "rand" }
 
-tokio = { version = "1.21.1", features = ["full", "tracing", "test-util"] }
+tokio = { version = "1.21.2", features = ["full", "tracing", "test-util"] }
 tokio-test = "0.4.2"
 tower-fallback = { path = "../tower-fallback/" }
 tower-test = "0.4.0"
diff --git a/tower-fallback/Cargo.toml b/tower-fallback/Cargo.toml
index 9fdf710c..e109fe2e 100644
--- a/tower-fallback/Cargo.toml
+++ b/tower-fallback/Cargo.toml
@@ -12,6 +12,6 @@ futures-core = "0.3.24"
 tracing = "0.1.36"
 
 [dev-dependencies]
-tokio = { version = "1.21.1", features = ["full", "tracing", "test-util"] }
+tokio = { version = "1.21.2", features = ["full", "tracing", "test-util"] }
 
 zebra-test = { path = "../zebra-test/" }
diff --git a/zebra-chain/Cargo.toml b/zebra-chain/Cargo.toml
index 50f05787..89c44ead 100644
--- a/zebra-chain/Cargo.toml
+++ b/zebra-chain/Cargo.toml
@@ -80,7 +80,7 @@ proptest-derive = { version = "0.3.0", optional = true }
 rand = { version = "0.8.5", optional = true, package = "rand" }
 rand_chacha = { version = "0.3.1", optional = true }
 
-tokio = { version = "1.21.1", features = ["tracing"], optional = true }
+tokio = { version = "1.21.2", features = ["tracing"], optional = true }
 
 zebra-test = { path = "../zebra-test/", optional = true }
 
@@ -103,7 +103,7 @@ proptest-derive = "0.3.0"
 rand = { version = "0.8.5", package = "rand" }
 rand_chacha = "0.3.1"
 
-tokio = { version = "1.21.1", features = ["full", "tracing", "test-util"] }
+tokio = { version = "1.21.2", features = ["full", "tracing", "test-util"] }
 
 zebra-test = { path = "../zebra-test/" }
 
diff --git a/zebra-consensus/Cargo.toml b/zebra-consensus/Cargo.toml
index ac6159e7..4f493963 100644
--- a/zebra-consensus/Cargo.toml
+++ b/zebra-consensus/Cargo.toml
@@ -29,7 +29,7 @@ futures = "0.3.24"
 futures-util = "0.3.24"
 metrics = "0.20.1"
 thiserror = "1.0.35"
-tokio = { version = "1.21.1", features = ["time", "sync", "tracing", "rt-multi-thread"] }
+tokio = { version = "1.21.2", features = ["time", "sync", "tracing", "rt-multi-thread"] }
 tower = { version = "0.4.13", features = ["timeout", "util", "buffer"] }
 tracing = "0.1.36"
 tracing-futures = "0.2.5"
@@ -60,7 +60,7 @@ proptest-derive = "0.3.0"
 rand07 = { package = "rand", version = "0.7" }
 spandoc = "0.2.2"
 
-tokio = { version = "1.21.1", features = ["full", "tracing", "test-util"] }
+tokio = { version = "1.21.2", features = ["full", "tracing", "test-util"] }
 tracing-error = "0.2.0"
 tracing-subscriber = "0.3.15"
 
diff --git a/zebra-network/Cargo.toml b/zebra-network/Cargo.toml
index 12b6b555..c226a357 100644
--- a/zebra-network/Cargo.toml
+++ b/zebra-network/Cargo.toml
@@ -30,7 +30,7 @@ serde = { version = "1.0.145", features = ["serde_derive"] }
 thiserror = "1.0.35"
 
 futures = "0.3.24"
-tokio = { version = "1.21.1", features = ["net", "time", "tracing", "macros", "rt-multi-thread"] }
+tokio = { version = "1.21.2", features = ["net", "time", "tracing", "macros", "rt-multi-thread"] }
 tokio-stream = { version = "0.1.10", features = ["sync", "time"] }
 tokio-util = { version = "0.7.4", features = ["codec"] }
 tower = { version = "0.4.13", features = ["retry", "discover", "load", "load-shed", "timeout", "util", "buffer"] }
@@ -55,7 +55,7 @@ proptest = "0.10.1"
 proptest-derive = "0.3.0"
 
 static_assertions = "1.1.0"
-tokio = { version = "1.21.1", features = ["full", "tracing", "test-util"] }
+tokio = { version = "1.21.2", features = ["full", "tracing", "test-util"] }
 toml = "0.5.9"
 
 zebra-chain = { path = "../zebra-chain", features = ["proptest-impl"] }
diff --git a/zebra-rpc/Cargo.toml b/zebra-rpc/Cargo.toml
index 1ee57bcb..fbb3eaaa 100644
--- a/zebra-rpc/Cargo.toml
+++ b/zebra-rpc/Cargo.toml
@@ -27,7 +27,7 @@ num_cpus = "1.13.1"
 serde_json = { version = "1.0.85", features = ["preserve_order"] }
 indexmap = { version = "1.9.1", features = ["serde"] }
 
-tokio = { version = "1.21.1", features = ["time", "rt-multi-thread", "macros", "tracing"] }
+tokio = { version = "1.21.2", features = ["time", "rt-multi-thread", "macros", "tracing"] }
 tower = "0.4.13"
 
 tracing = "0.1.36"
@@ -51,7 +51,7 @@ proptest-derive = "0.3.0"
 serde_json = "1.0.85"
 thiserror = "1.0.35"
 
-tokio = { version = "1.21.1", features = ["full", "tracing", "test-util"] }
+tokio = { version = "1.21.2", features = ["full", "tracing", "test-util"] }
 
 zebra-chain = { path = "../zebra-chain", features = ["proptest-impl"] }
 zebra-state = { path = "../zebra-state", features = ["proptest-impl"] }
diff --git a/zebra-state/Cargo.toml b/zebra-state/Cargo.toml
index 8a5d4bc9..03b19365 100644
--- a/zebra-state/Cargo.toml
+++ b/zebra-state/Cargo.toml
@@ -27,7 +27,7 @@ tempfile = "3.3.0"
 thiserror = "1.0.35"
 
 rayon = "1.5.3"
-tokio = { version = "1.21.1", features = ["sync", "tracing"] }
+tokio = { version = "1.21.2", features = ["sync", "tracing"] }
 tower = { version = "0.4.13", features = ["buffer", "util"] }
 tracing = "0.1.36"
 
@@ -55,7 +55,7 @@ proptest-derive = "0.3.0"
 halo2 = { package = "halo2_proofs", version = "0.2.0" }
 jubjub = "0.9.0"
 
-tokio = { version = "1.21.1", features = ["full", "tracing", "test-util"] }
+tokio = { version = "1.21.2", features = ["full", "tracing", "test-util"] }
 
 zebra-chain = { path = "../zebra-chain", features = ["proptest-impl"] }
 zebra-test = { path = "../zebra-test/" }
diff --git a/zebra-test/Cargo.toml b/zebra-test/Cargo.toml
index 7682f00a..c1342aa8 100644
--- a/zebra-test/Cargo.toml
+++ b/zebra-test/Cargo.toml
@@ -17,7 +17,7 @@ once_cell = "1.15.0"
 rand = { version = "0.8.5", package = "rand" }
 regex = "1.6.0"
 
-tokio = { version = "1.21.1", features = ["full", "tracing", "test-util"] }
+tokio = { version = "1.21.2", features = ["full", "tracing", "test-util"] }
 tower = { version = "0.4.13", features = ["util"] }
 futures = "0.3.24"
 
diff --git a/zebrad/Cargo.toml b/zebrad/Cargo.toml
index 91efc281..c3b1cfd5 100644
--- a/zebrad/Cargo.toml
+++ b/zebrad/Cargo.toml
@@ -87,7 +87,7 @@ toml = "0.5.9"
 
 futures = "0.3.24"
 rayon = "1.5.3"
-tokio = { version = "1.21.1", features = ["time", "rt-multi-thread", "macros", "tracing", "signal"] }
+tokio = { version = "1.21.2", features = ["time", "rt-multi-thread", "macros", "tracing", "signal"] }
 tower = { version = "0.4.13", features = ["hedge", "limit"] }
 pin-project = "1.0.12"
 
@@ -162,7 +162,7 @@ tempfile = "3.3.0"
 hyper = { version = "0.14.20", features = ["http1", "http2", "server"]}
 reqwest = "0.11.12"
 
-tokio = { version = "1.21.1", features = ["full", "tracing", "test-util"] }
+tokio = { version = "1.21.2", features = ["full", "tracing", "test-util"] }
 tokio-stream = "0.1.10"
 
 # test feature lightwalletd-grpc-tests