diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 944cf73c..a1c8f2bf 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -25,11 +25,12 @@ repos:
         language: system
         pass_filenames: false
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.16.4
+    rev: v0.16.5
     hooks:
       - id: ruff
         args: ["--fix"]
       - id: ruff-format
+        args: ["--preview"]
       # The following can be removed once PLR0917 is out of preview
       - name: ruff preview rules
         id: ruff
diff --git a/README.md b/README.md
index 93f6dd03..9300ccc1 100644
--- a/README.md
+++ b/README.md
@@ -13,6 +13,7 @@ To use the project, simply install our package `zarrs` from PyPI (which depends
 
 ```python
 import zarr
+
 zarr.config.set({"codec_pipeline.path": "zarrs.ZarrsCodecPipeline"})
 ```
 
@@ -68,8 +69,8 @@ zarr.config.set({
         "chunk_concurrent_minimum": 4,
         "file_handle_cache_size": 0,
         "direct_io": False,
-        "strict": False
-    }
+        "strict": False,
+    },
 })
 ```
 
diff --git a/src/lib.rs b/src/lib.rs
index 3ce7eb2e..9ef05f2d 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -43,7 +43,7 @@ use crate::utils::{PyCodecErrExt, PyErrExt as _};
 // TODO: Use a OnceLock for store with get_or_try_init when stabilised?
 #[gen_stub_pyclass]
 #[pyclass]
-pub struct CodecPipelineImpl {
+pub(crate) struct CodecPipelineImpl {
     pub(crate) store: ReadableWritableListableStorage,
     pub(crate) codec_chain: Arc<CodecChain>,
     pub(crate) codec_options: CodecOptions,
@@ -257,17 +257,15 @@ impl CodecPipelineImpl {
             DataType::from_metadata(&metadata_v3.data_type).map_py_err::<PyTypeError>()?;
         let fill_value = data_type
             .fill_value(&metadata_v3.fill_value, ZarrVersion::V3)
-            .or_else(|_| {
-                Err(match &metadata {
-                    ArrayMetadata::V2(metadata) => format!(
-                        "incompatible fill value metadata: dtype={}, fill_value={}",
-                        metadata.dtype, metadata.fill_value
-                    ),
-                    ArrayMetadata::V3(metadata) => format!(
-                        "incompatible fill value metadata: data_type={}, fill_value={}",
-                        metadata.data_type, metadata.fill_value
-                    ),
-                })
+            .map_err(|_| match &metadata {
+                ArrayMetadata::V2(metadata) => format!(
+                    "incompatible fill value metadata: dtype={}, fill_value={}",
+                    metadata.dtype, metadata.fill_value
+                ),
+                ArrayMetadata::V3(metadata) => format!(
+                    "incompatible fill value metadata: data_type={}, fill_value={}",
+                    metadata.data_type, metadata.fill_value
+                ),
             })
             .map_py_err::<PyTypeError>()?;
 
@@ -469,11 +467,14 @@ impl CodecPipelineImpl {
 
 /// A Python module implemented in Rust.
 #[pymodule]
-fn _internal(m: &Bound<'_, PyModule>) -> PyResult<()> {
-    m.add("__version__", env!("CARGO_PKG_VERSION"))?;
-    m.add_class::<CodecPipelineImpl>()?;
-    m.add_class::<chunk_item::ChunkItem>()?;
-    Ok(())
+pub mod _internal {
+    #[pymodule_export]
+    #[allow(non_upper_case_globals)]
+    const __version__: &str = env!("CARGO_PKG_VERSION");
+    #[pymodule_export]
+    use super::CodecPipelineImpl;
+    #[pymodule_export]
+    use super::chunk_item::ChunkItem;
 }
 
 define_stub_info_gatherer!(stub_info);
diff --git a/src/store.rs b/src/store.rs
index 335c77bd..0176fa85 100644
--- a/src/store.rs
+++ b/src/store.rs
@@ -72,7 +72,7 @@ impl<'py> FromPyObject<'_, 'py> for StoreConfig {
 }
 
 impl StoreConfig {
-    pub fn direct_io(&mut self, flag: bool) -> () {
+    pub fn direct_io(&mut self, flag: bool) {
         match self {
             StoreConfig::Filesystem(config) => config.direct_io(flag),
             StoreConfig::Http(_config) => (),
diff --git a/src/store/filesystem.rs b/src/store/filesystem.rs
index 0eb59212..37dd8c1c 100644
--- a/src/store/filesystem.rs
+++ b/src/store/filesystem.rs
@@ -22,7 +22,7 @@ impl FilesystemStoreConfig {
         }
     }
 
-    pub fn direct_io(&mut self, flag: bool) -> () {
+    pub fn direct_io(&mut self, flag: bool) {
         self.opts.direct_io(flag);
     }
 
diff --git a/tests/conftest.py b/tests/conftest.py
index 33cb1295..6451a656 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -55,7 +55,8 @@ async def store(request: pytest.FixtureRequest, tmp_path: Path) -> Store:
 def array_fixture(request: pytest.FixtureRequest) -> npt.NDArray[Any]:
     array_request: ArrayRequest = request.param
     return (
-        np.arange(np.prod(array_request.shape))
+        np
+        .arange(np.prod(array_request.shape))
         .reshape(array_request.shape, order=array_request.order)
         .astype(array_request.dtype)
     )
diff --git a/tests/pipeline/conftest.py b/tests/pipeline/conftest.py
index 8afbe77f..4259ac8e 100644
--- a/tests/pipeline/conftest.py
+++ b/tests/pipeline/conftest.py
@@ -113,14 +113,12 @@ def roundtrip_params() -> Generator[ParameterSet]:
             if sum(isinstance(i, EllipsisType) for i in index) > 1:
                 continue
             for indexing_method_param in indexing_method_params:
-                id = "-".join(
-                    [
-                        str(indexing_method_param.id),
-                        f"{dimensionality}d",
-                        *(str(index_param.id) for index_param in index_param_prod),
-                        f"v{format}",
-                    ]
-                )
+                id = "-".join([
+                    str(indexing_method_param.id),
+                    f"{dimensionality}d",
+                    *(str(index_param.id) for index_param in index_param_prod),
+                    f"v{format}",
+                ])
                 indexing_method = indexing_method_param.values[0]
                 yield pytest.param(
                     (format, dimensionality, index, indexing_method), id=id
diff --git a/tests/pipeline/test_pipeline.py b/tests/pipeline/test_pipeline.py
index b2f0c135..805704d5 100644
--- a/tests/pipeline/test_pipeline.py
+++ b/tests/pipeline/test_pipeline.py
@@ -98,19 +98,15 @@ def test_pipeline_used(
 
 @pytest.fixture
 def use_zarrs_direct_io() -> Generator[None]:
-    zarr.config.set(
-        {
-            "codec_pipeline.path": "zarrs.ZarrsCodecPipeline",
-            "codec_pipeline.direct_io": True,
-        }
-    )
+    zarr.config.set({
+        "codec_pipeline.path": "zarrs.ZarrsCodecPipeline",
+        "codec_pipeline.direct_io": True,
+    })
     yield
-    zarr.config.set(
-        {
-            "codec_pipeline.path": "zarrs.ZarrsCodecPipeline",
-            "codec_pipeline.direct_io": False,
-        }
-    )
+    zarr.config.set({
+        "codec_pipeline.path": "zarrs.ZarrsCodecPipeline",
+        "codec_pipeline.direct_io": False,
+    })
 
 
 @pytest.mark.skipif(
@@ -154,12 +150,10 @@ def test_file_handle_cache(tmp_path: Path, cache_size: int) -> None:
     path = tmp_path / "foo.zarr"
     ground_truth_arr = _sharded_array(path)
 
-    with zarr.config.set(
-        {
-            "codec_pipeline.path": "zarrs.ZarrsCodecPipeline",
-            "codec_pipeline.file_handle_cache_size": cache_size,
-        }
-    ):
+    with zarr.config.set({
+        "codec_pipeline.path": "zarrs.ZarrsCodecPipeline",
+        "codec_pipeline.file_handle_cache_size": cache_size,
+    }):
         before = _open_fds()
         z = zarr.open_array(path, mode="r")
         np.testing.assert_array_equal(z[...], ground_truth_arr)
diff --git a/tests/pipeline/test_roundtrip.py b/tests/pipeline/test_roundtrip.py
index db4cb4e6..a0a7ed03 100644
--- a/tests/pipeline/test_roundtrip.py
+++ b/tests/pipeline/test_roundtrip.py
@@ -90,9 +90,9 @@ def indexing_method(roundtrip: tuple[Literal[2, 3], int, Index, Callable]) -> Ca
 
 @contextmanager
 def use_zarr_default_codec_reader() -> Generator[None]:
-    zarr.config.set(
-        {"codec_pipeline.path": "zarr.core.codec_pipeline.BatchedCodecPipeline"}
-    )
+    zarr.config.set({
+        "codec_pipeline.path": "zarr.core.codec_pipeline.BatchedCodecPipeline"
+    })
     yield
     zarr.config.set({"codec_pipeline.path": "zarrs.ZarrsCodecPipeline"})
 
diff --git a/tests/test_zarrs_http.py b/tests/test_zarrs_http.py
index 661f8516..45b08d76 100644
--- a/tests/test_zarrs_http.py
+++ b/tests/test_zarrs_http.py
@@ -6,18 +6,16 @@
 import zarr
 from zarr.storage import FsspecStore
 
-ARR_REF = np.array(
-    [
-        [np.nan, np.nan, np.nan, np.nan, 0.1, 0.1, -0.6, 0.1],
-        [np.nan, np.nan, np.nan, np.nan, 0.1, 0.1, -1.6, 0.1],
-        [np.nan, np.nan, np.nan, np.nan, 0.1, 0.1, -2.6, 0.1],
-        [np.nan, np.nan, np.nan, np.nan, -3.4, -3.5, -3.6, 0.1],
-        [1.0, 1.0, 1.0, -4.3, -4.4, -4.5, -4.6, 1.1],
-        [1.0, 1.0, 1.0, -5.3, -5.4, -5.5, -5.6, 1.1],
-        [1.0, 1.0, 1.0, 1.0, 1.1, 1.1, -6.6, 1.1],
-        [1.0, 1.0, 1.0, 1.0, -7.4, -7.5, -7.6, -7.7],
-    ]
-)
+ARR_REF = np.array([
+    [np.nan, np.nan, np.nan, np.nan, 0.1, 0.1, -0.6, 0.1],
+    [np.nan, np.nan, np.nan, np.nan, 0.1, 0.1, -1.6, 0.1],
+    [np.nan, np.nan, np.nan, np.nan, 0.1, 0.1, -2.6, 0.1],
+    [np.nan, np.nan, np.nan, np.nan, -3.4, -3.5, -3.6, 0.1],
+    [1.0, 1.0, 1.0, -4.3, -4.4, -4.5, -4.6, 1.1],
+    [1.0, 1.0, 1.0, -5.3, -5.4, -5.5, -5.6, 1.1],
+    [1.0, 1.0, 1.0, 1.0, 1.1, 1.1, -6.6, 1.1],
+    [1.0, 1.0, 1.0, 1.0, -7.4, -7.5, -7.6, -7.7],
+])
 
 URL = "https://raw.githubusercontent.com/zarrs/zarrs/main/zarrs/tests/data/array_write_read.zarr/group/array"