diff --git a/Cargo.lock b/Cargo.lock
index 327292c9..9bae0531 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1616,7 +1616,7 @@ checksum = "f7c45b9784283f1b2e7fb61b42047c2fd678ef0960d4f6f1eba131594cc369d4"
 
 [[package]]
 name = "ry"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "jiff",
  "pyo3",
@@ -1628,7 +1628,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "jiff",
  "pyo3",
@@ -1673,7 +1673,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-brotli"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "brotli",
  "pyo3",
@@ -1681,7 +1681,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-bytes"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "ahash",
  "bytes",
@@ -1690,7 +1690,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-bzip2"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "bzip2",
  "pyo3",
@@ -1698,7 +1698,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-core"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "pyo3-build-config",
@@ -1706,7 +1706,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-dev"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "ryo3-bytes",
@@ -1719,7 +1719,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-dirs"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "dirs",
  "pyo3",
@@ -1727,7 +1727,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-flate2"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "flate2",
  "pyo3",
@@ -1736,7 +1736,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-fnv"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "fnv",
  "pyo3",
@@ -1744,7 +1744,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-fspath"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "ryo3-bytes",
@@ -1756,7 +1756,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-globset"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "globset",
  "pyo3",
@@ -1765,7 +1765,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-heck"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "heck",
  "pyo3",
@@ -1773,7 +1773,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-http"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "http",
  "pyo3",
@@ -1784,7 +1784,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-jiff"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "jiff",
  "pyo3",
@@ -1795,7 +1795,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-jiter"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "jiter",
  "pyo3",
@@ -1804,21 +1804,21 @@ dependencies = [
 
 [[package]]
 name = "ryo3-macros"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
 ]
 
 [[package]]
 name = "ryo3-quick-maths"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
 ]
 
 [[package]]
 name = "ryo3-regex"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "regex",
@@ -1826,7 +1826,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-reqwest"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "bytes",
  "futures-core",
@@ -1847,7 +1847,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-same-file"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "ryo3-core",
@@ -1856,7 +1856,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-shlex"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "shlex",
@@ -1864,7 +1864,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-size"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "size",
@@ -1872,7 +1872,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-sqlformat"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "sqlformat",
@@ -1880,7 +1880,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-std"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "bytes",
  "pyo3",
@@ -1891,7 +1891,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-tokio"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "pyo3-async-runtimes",
@@ -1902,7 +1902,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-unindent"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "unindent",
@@ -1910,7 +1910,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-url"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "ryo3-macros",
@@ -1919,7 +1919,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-walkdir"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "ryo3-core",
@@ -1930,7 +1930,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-which"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "ryo3-regex",
@@ -1939,7 +1939,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-xxhash"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "ryo3-bytes",
@@ -1948,7 +1948,7 @@ dependencies = [
 
 [[package]]
 name = "ryo3-zstd"
-version = "0.0.35"
+version = "0.0.36"
 dependencies = [
  "pyo3",
  "zstd",
diff --git a/crates/ryo3-fnv/src/lib.rs b/crates/ryo3-fnv/src/lib.rs
index 9fe287a2..69301908 100644
--- a/crates/ryo3-fnv/src/lib.rs
+++ b/crates/ryo3-fnv/src/lib.rs
@@ -2,8 +2,9 @@
 use std::hash::Hasher;
 
 use ::fnv as fnv_rs;
-use pyo3::types::PyModule;
-use pyo3::{intern, prelude::*};
+use pyo3::types::{PyModule, PyTuple};
+
+use pyo3::{intern, prelude::*, IntoPyObjectExt};
 use pyo3::{wrap_pyfunction, PyResult};
 
 #[pyclass(name = "FnvHasher", module = "ryo3")]
@@ -14,20 +15,38 @@ pub struct PyFnvHasher {
 #[pymethods]
 impl PyFnvHasher {
     #[new]
-    #[pyo3(signature = (s = None))]
-    fn py_new(s: Option<&[u8]>) -> Self {
-        match s {
-            Some(s) => {
+    #[pyo3(signature = (s = None, *, key = None))]
+    fn py_new(s: Option<&[u8]>, key: Option<u64>) -> Self {
+        match (key, s) {
+            (Some(k), Some(s)) => {
+                let mut hasher = fnv_rs::FnvHasher::with_key(k);
+                hasher.write(s);
+                Self { hasher }
+            }
+            (Some(k), None) => Self {
+                hasher: fnv_rs::FnvHasher::with_key(k),
+            },
+            (None, Some(s)) => {
                 let mut hasher = fnv_rs::FnvHasher::default();
                 hasher.write(s);
                 Self { hasher }
             }
-            None => Self {
+            (None, None) => Self {
                 hasher: fnv_rs::FnvHasher::default(),
             },
         }
     }
 
+    fn __getnewargs__<'py>(&self, py: Python<'py>) -> PyResult<Bound<'py, PyTuple>> {
+        PyTuple::new(
+            py,
+            [
+                py.None().into_bound_py_any(py)?,
+                self.hasher.finish().into_bound_py_any(py)?,
+            ],
+        )
+    }
+
     fn __str__(&self) -> String {
         format!("fnv1a<{:x}>", self.hasher.finish())
     }
@@ -63,8 +82,19 @@ impl PyFnvHasher {
 }
 
 #[pyfunction]
-pub fn fnv1a(s: &[u8]) -> PyResult<PyFnvHasher> {
-    Ok(PyFnvHasher::py_new(Some(s)))
+#[pyo3(signature = (s, key = None))]
+pub fn fnv1a(s: &[u8], key: Option<u64>) -> PyResult<PyFnvHasher> {
+    Ok(PyFnvHasher {
+        hasher: if let Some(k) = key {
+            let mut hasher = fnv_rs::FnvHasher::with_key(k);
+            hasher.write(s);
+            hasher
+        } else {
+            let mut hasher = fnv_rs::FnvHasher::default();
+            hasher.write(s);
+            hasher
+        },
+    })
 }
 
 pub fn pymod_add(m: &Bound<'_, PyModule>) -> PyResult<()> {