diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2a74553b4..970e7417a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -59,6 +59,26 @@ jobs:
       - name: Check unused dependencies
         run: cargo machete
 
+  unused_dependencies:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: 'recursive'
+      - uses: dtolnay/rust-toolchain@nightly
+      - name: install protoc
+        uses: taiki-e/install-action@v2
+        with:
+          tool: protoc@${{ env.PROTOC_VERSION }}
+      - name: install ninja
+        uses: ./.github/actions/setup-ninja
+      - name: install cargo-udeps
+        uses: taiki-e/install-action@cargo-udeps
+      - name: cargo udeps
+        run: cargo +nightly udeps
+      - name: cargo udeps all-targets
+        run: cargo +nightly udeps --all-targets
+
   test:
     runs-on: ${{ matrix.os }}
     strategy:
diff --git a/fuzz/Cargo.toml b/fuzz/Cargo.toml
index 03a7ebcfb..a29cf70aa 100644
--- a/fuzz/Cargo.toml
+++ b/fuzz/Cargo.toml
@@ -13,7 +13,6 @@ cargo-fuzz = true
 
 [dependencies]
 libfuzzer-sys = { git = "https://github.com/rust-fuzz/libfuzzer-sys.git" }
-protobuf = { path = "../protobuf" }
 tests = { path = "../tests" }
 
 [[bin]]
diff --git a/prost/Cargo.toml b/prost/Cargo.toml
index 965505733..8dacdd3b3 100644
--- a/prost/Cargo.toml
+++ b/prost/Cargo.toml
@@ -34,8 +34,6 @@ prost-derive = { version = "0.12.4", path = "../prost-derive", optional = true }
 
 [dev-dependencies]
 criterion = { version = "0.4", default-features = false }
-env_logger = { version = "0.10", default-features = false }
-log = "0.4"
 proptest = "1"
 rand = "0.8"
 
diff --git a/tests-2015/Cargo.toml b/tests-2015/Cargo.toml
index e98e1dbb4..2effd2cc6 100644
--- a/tests-2015/Cargo.toml
+++ b/tests-2015/Cargo.toml
@@ -21,14 +21,12 @@ std = []
 
 [dependencies]
 anyhow = "1.0.1"
-bytes = "1"
 cfg-if = "1"
 prost = { path = "../prost" }
 prost-types = { path = "../prost-types" }
 protobuf = { path = "../protobuf" }
 
 [dev-dependencies]
-diff = "0.1"
 prost-build = { path = "../prost-build" }
 tempfile = "3"
 
@@ -36,4 +34,3 @@ tempfile = "3"
 cfg-if = "1"
 env_logger = { version = "0.10", default-features = false }
 prost-build = { path = "../prost-build" }
-protobuf = { path = "../protobuf" }
diff --git a/tests-no-std/Cargo.toml b/tests-no-std/Cargo.toml
index 70ae96612..e1e0ddd85 100644
--- a/tests-no-std/Cargo.toml
+++ b/tests-no-std/Cargo.toml
@@ -22,19 +22,16 @@ path = "../tests/src/lib.rs"
 
 [dependencies]
 anyhow = { version = "1.0.45", default-features = false }
-bytes = { version = "1", default-features = false }
 cfg-if = "1"
 prost = { path = "../prost", default-features = false, features = ["derive"] }
 prost-types = { path = "../prost-types", default-features = false }
-protobuf = { path = "../protobuf" }
 
 [dev-dependencies]
-diff = "0.1"
 prost-build = { path = "../prost-build" }
 tempfile = "3"
+protobuf = { path = "../protobuf" }
 
 [build-dependencies]
 cfg-if = "1"
 env_logger = { version = "0.10", default-features = false }
 prost-build = { path = "../prost-build" }
-protobuf = { path = "../protobuf" }
diff --git a/tests/Cargo.toml b/tests/Cargo.toml
index 0dd709881..3a7406f9d 100644
--- a/tests/Cargo.toml
+++ b/tests/Cargo.toml
@@ -16,19 +16,16 @@ std = []
 
 [dependencies]
 anyhow = "1.0.1"
-# bytes = "1"
 cfg-if = "1"
 prost = { path = "../prost" }
 prost-types = { path = "../prost-types" }
-protobuf = { path = "../protobuf" }
 
 [dev-dependencies]
-diff = "0.1"
 prost-build = { path = "../prost-build", features = ["cleanup-markdown"] }
 tempfile = "3"
+protobuf = { path = "../protobuf" }
 
 [build-dependencies]
 cfg-if = "1"
 env_logger = { version = "0.10", default-features = false }
 prost-build = { path = "../prost-build" }
-protobuf = { path = "../protobuf" }
diff --git a/tests/src/lib.rs b/tests/src/lib.rs
index 00926afe0..6674ddddd 100644
--- a/tests/src/lib.rs
+++ b/tests/src/lib.rs
@@ -13,7 +13,6 @@ extern crate alloc;
 cfg_if! {
     if #[cfg(feature = "edition-2015")] {
         extern crate anyhow;
-        extern crate bytes;
         extern crate core;
         extern crate prost;
         extern crate prost_types;