diff --git a/.github/workflows/check.yml b/.github/workflows/check.yml
index fdeabfaa5e..94b7ff2447 100644
--- a/.github/workflows/check.yml
+++ b/.github/workflows/check.yml
@@ -83,7 +83,6 @@ jobs:
           git clone --depth=1 https://github.com/nss-dev/nss "$NSS_DIR"
           echo "NSS_DIR=$NSS_DIR" >> "$GITHUB_ENV"
           echo "NSPR_DIR=$NSPR_DIR" >> "$GITHUB_ENV"
-          echo "NSS_JOBS=$NUMBER_OF_PROCESSORS" >> "$GITHUB_ENV"
         env:
           NSS_DIR: ${{ github.workspace }}/nss
           NSPR_DIR: ${{ github.workspace }}/nspr
@@ -107,7 +106,7 @@ jobs:
           RUST_BACKTRACE: 1
 
       - name: Run tests and determine coverage
-        run: cargo +${{ matrix.rust-toolchain }} llvm-cov test --all-targets --no-fail-fast --lcov --output-path lcov.info
+        run: cargo +${{ matrix.rust-toolchain }} llvm-cov test --features ci --all-targets --no-fail-fast --lcov --output-path lcov.info
         env:
           RUST_BACKTRACE: 1
           RUST_LOG: neqo=debug
diff --git a/neqo-common/Cargo.toml b/neqo-common/Cargo.toml
index b3486e7220..68583e21dc 100644
--- a/neqo-common/Cargo.toml
+++ b/neqo-common/Cargo.toml
@@ -16,6 +16,7 @@ time = {version = "=0.3.23", features = ["formatting"]}
 
 [features]
 deny-warnings = []
+ci = []
 
 [target."cfg(windows)".dependencies.winapi]
 version = "0.3"
diff --git a/neqo-common/src/hrtime.rs b/neqo-common/src/hrtime.rs
index d1f42d41c5..682c097035 100644
--- a/neqo-common/src/hrtime.rs
+++ b/neqo-common/src/hrtime.rs
@@ -372,7 +372,12 @@ impl Drop for Time {
     }
 }
 
-#[cfg(test)]
+// Only run these tests in CI on platforms other than MacOS and Windows, where the timer
+// inaccuracies are too high to pass the tests.
+#[cfg(all(
+    test,
+    not(all(any(target_os = "macos", target_os = "windows"), feature = "ci"))
+))]
 mod test {
     use super::Time;
     use std::{
diff --git a/neqo-crypto/src/ech.rs b/neqo-crypto/src/ech.rs
index 5425e1a64c..c4b33b0bee 100644
--- a/neqo-crypto/src/ech.rs
+++ b/neqo-crypto/src/ech.rs
@@ -109,6 +109,7 @@ pub fn generate_keys() -> Res<(PrivateKey, PublicKey)> {
 
     // If we have tracing on, try to ensure that key data can be read.
     let insensitive_secret_ptr = if log::log_enabled!(log::Level::Trace) {
+        #[allow(clippy::useless_conversion)] // TODO: Remove when we bump the MSRV to 1.74.0.
         unsafe {
             p11::PK11_GenerateKeyPairWithOpFlags(
                 *slot,
@@ -126,6 +127,7 @@ pub fn generate_keys() -> Res<(PrivateKey, PublicKey)> {
     };
     assert_eq!(insensitive_secret_ptr.is_null(), public_ptr.is_null());
     let secret_ptr = if insensitive_secret_ptr.is_null() {
+        #[allow(clippy::useless_conversion)] // TODO: Remove when we bump the MSRV to 1.74.0.
         unsafe {
             p11::PK11_GenerateKeyPairWithOpFlags(
                 *slot,
diff --git a/neqo-crypto/src/hkdf.rs b/neqo-crypto/src/hkdf.rs
index 3745d646d5..44df30ecfd 100644
--- a/neqo-crypto/src/hkdf.rs
+++ b/neqo-crypto/src/hkdf.rs
@@ -68,6 +68,7 @@ pub fn import_key(version: Version, buf: &[u8]) -> Res<SymKey> {
         return Err(Error::UnsupportedVersion);
     }
     let slot = Slot::internal()?;
+    #[allow(clippy::useless_conversion)] // TODO: Remove when we bump the MSRV to 1.74.0.
     let key_ptr = unsafe {
         PK11_ImportDataKey(
             *slot,
diff --git a/neqo-crypto/src/hp.rs b/neqo-crypto/src/hp.rs
index fea67e9953..2409521903 100644
--- a/neqo-crypto/src/hp.rs
+++ b/neqo-crypto/src/hp.rs
@@ -72,6 +72,7 @@ impl HpKey {
         let l = label.as_bytes();
         let mut secret: *mut PK11SymKey = null_mut();
 
+        #[allow(clippy::useless_conversion)] // TODO: Remove when we bump the MSRV to 1.74.0.
         let (mech, key_size) = match cipher {
             TLS_AES_128_GCM_SHA256 => (CK_MECHANISM_TYPE::from(CKM_AES_ECB), 16),
             TLS_AES_256_GCM_SHA384 => (CK_MECHANISM_TYPE::from(CKM_AES_ECB), 32),
@@ -99,6 +100,8 @@ impl HpKey {
 
         let res = match cipher {
             TLS_AES_128_GCM_SHA256 | TLS_AES_256_GCM_SHA384 => {
+                // TODO: Remove when we bump the MSRV to 1.74.0.
+                #[allow(clippy::useless_conversion)]
                 let context_ptr = unsafe {
                     PK11_CreateContextBySymKey(
                         mech,
@@ -171,6 +174,8 @@ impl HpKey {
                 };
                 let mut output_len: c_uint = 0;
                 let mut param_item = Item::wrap_struct(&params);
+                // TODO: Remove when we bump the MSRV to 1.74.0.
+                #[allow(clippy::useless_conversion)]
                 secstatus_to_res(unsafe {
                     PK11_Encrypt(
                         **key,
diff --git a/neqo-crypto/src/p11.rs b/neqo-crypto/src/p11.rs
index c7e47cbf15..ebd641c17e 100644
--- a/neqo-crypto/src/p11.rs
+++ b/neqo-crypto/src/p11.rs
@@ -130,6 +130,7 @@ impl PrivateKey {
     /// When the values are too large to fit.  So never.
     pub fn key_data(&self) -> Res<Vec<u8>> {
         let mut key_item = Item::make_empty();
+        #[allow(clippy::useless_conversion)] // TODO: Remove when we bump the MSRV to 1.74.0.
         secstatus_to_res(unsafe {
             PK11_ReadRawAttribute(
                 PK11ObjectType::PK11_TypePrivKey,