diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2293e49..90968f0 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -12,30 +12,32 @@ env:
   CARGO_INCREMENTAL: 0
   RUST_BACKTRACE: 1
   # Faster crates.io index checkout.
-  # Enable once the MSRV is >= 1.68
-  #CARGO_REGISTRIES_CRATES_IO_PROTOCOL: sparse
+  CARGO_REGISTRIES_CRATES_IO_PROTOCOL: sparse
   RUST_LOG: debug
 
 jobs:
   check_clippy:
-#    runs-on: ubuntu-24.04
-    runs-on: self-hosted
+    runs-on: ubuntu-24.04
     name: Clippy
     steps:
       - uses: actions/checkout@v4
       - name: Run cargo clippy
-        run: cargo clippy --workspace --all-features -- -D warnings
+        run: |
+          rustup component add clippy
+          cargo clippy --workspace --all-features -- -D warnings
 
   check_fmt:
-    runs-on: self-hosted
+    runs-on: ubuntu-24.04
     name: Checking fmt
     steps:
       - uses: actions/checkout@v4
       - name: Run cargo fmt
-        run: cargo fmt --all -- --check
+        run: |
+          rustup component add rustfmt
+          cargo fmt --all -- --check
 
   rustdoc:
-    runs-on: self-hosted
+    runs-on: ubuntu-24.04
     name: Rustdoc
     steps:
       - uses: actions/checkout@v4
@@ -43,7 +45,7 @@ jobs:
         run: cargo rustdoc --all-features -- -D warnings
 
   build:
-    runs-on: self-hosted
+    runs-on: ubuntu-24.04
     name: Release build
     steps:
       - uses: actions/checkout@v4
@@ -51,7 +53,7 @@ jobs:
         run: cargo build --release
 
   benches:
-    runs-on: self-hosted
+    runs-on: ubuntu-24.04
     name: Run benchmarks
     steps:
       - uses: actions/checkout@v4
@@ -59,7 +61,7 @@ jobs:
         run: cargo bench --all-targets
 
   test:
-    runs-on: self-hosted
+    runs-on: ubuntu-24.04
     name: Run cargo test
     strategy:
       matrix:
diff --git a/rust-toolchain b/rust-toolchain
index 0403bed..68bc7ff 100644
--- a/rust-toolchain
+++ b/rust-toolchain
@@ -1 +1 @@
-1.66.1
+1.71.1
diff --git a/src/hash_impl.rs b/src/hash_impl.rs
index 5eec9b1..3b5f668 100644
--- a/src/hash_impl.rs
+++ b/src/hash_impl.rs
@@ -43,7 +43,7 @@ impl<H: Hasher, const N: usize> Hashable<H> for [u8; N] {
 
     #[allow(trivial_casts, unsafe_code)]
     fn hash_slice(data: &[[u8; N]], state: &mut H) {
-        let newlen = data.len() * mem::size_of::<[u8; N]>();
+        let newlen = mem::size_of_val(data);
         let ptr = data.as_ptr() as *const u8;
         state.write(unsafe { slice::from_raw_parts(ptr, newlen) })
     }
diff --git a/src/merkle.rs b/src/merkle.rs
index ba17492..4e89b40 100644
--- a/src/merkle.rs
+++ b/src/merkle.rs
@@ -1629,7 +1629,7 @@ impl<
 
         let mut data = S::new(size).expect("failed to create data store");
 
-        populate_data_par::<E, A, S, BaseTreeArity, _>(&mut data, iter)?;
+        populate_data_par::<E, A, S, _>(&mut data, iter)?;
         let root = S::build::<A, BaseTreeArity>(&mut data, leafs, row_count, None)?;
 
         Ok(MerkleTree {
@@ -1689,7 +1689,7 @@ impl<
             });
         }
 
-        populate_data_par::<E, A, S, BaseTreeArity, _>(&mut data, iter)?;
+        populate_data_par::<E, A, S, _>(&mut data, iter)?;
         let root = S::build::<A, BaseTreeArity>(&mut data, leafs, row_count, Some(config))?;
 
         Ok(MerkleTree {
@@ -2049,12 +2049,11 @@ pub fn populate_data<
     Ok(())
 }
 
-fn populate_data_par<E, A, S, BaseTreeArity, I>(data: &mut S, iter: I) -> Result<()>
+fn populate_data_par<E, A, S, I>(data: &mut S, iter: I) -> Result<()>
 where
     E: Element,
     A: Algorithm<E>,
     S: Store<E>,
-    BaseTreeArity: Unsigned,
     I: ParallelIterator<Item = E> + IndexedParallelIterator,
 {
     if !data.is_empty() {