diff --git a/python/python/lancedb/functions.py b/python/python/lancedb/functions.py
index ae40b4e3f..2125542af 100644
--- a/python/python/lancedb/functions.py
+++ b/python/python/lancedb/functions.py
@@ -283,6 +283,7 @@ class PythonEnvironmentSpec(_RemoteValue):
     path: Optional[str] = None
     modules: tuple[str, ...] = ()
     image: Optional[str] = None
+    system_packages: tuple[str, ...] = ()
 
 
 class PythonRuntimeSpec(_RemoteValue):
@@ -1854,6 +1855,7 @@ class UdfDefinition:
         gpu: bool = False,
         conda: tuple[str, ...] = (),
         conda_channels: tuple[str, ...] = (),
+        apt: tuple[str, ...] = (),
         code: tuple[types.ModuleType, ...] = (),
     ):
         is_class = inspect.isclass(function)
@@ -1869,14 +1871,23 @@ class UdfDefinition:
         if conda_channels and not conda:
             raise ValueError("conda_channels requires conda packages")
         packages = tuple(sorted(set(conda if conda else pip)))
-        if any(not package or package != package.strip() for package in packages):
+        system_packages = tuple(sorted(set(apt)))
+        if any(
+            not package or package != package.strip()
+            for package in packages + system_packages
+        ):
             raise ValueError("package requirements must be non-empty and trimmed")
         if conda:
             environment_spec = PythonEnvironmentSpec(
-                kind="conda", packages=packages, channels=tuple(conda_channels)
+                kind="conda",
+                packages=packages,
+                channels=tuple(conda_channels),
+                system_packages=system_packages,
             )
         else:
-            environment_spec = PythonEnvironmentSpec(kind="pip", packages=packages)
+            environment_spec = PythonEnvironmentSpec(
+                kind="pip", packages=packages, system_packages=system_packages
+            )
         environment = dict(env)
         if any(
             not isinstance(key, str) or not isinstance(value, str)
@@ -2045,6 +2056,7 @@ def udf(
     gpu: bool = False,
     conda: tuple[str, ...] | list[str] = (),
     conda_channels: tuple[str, ...] | list[str] = (),
+    apt: tuple[str, ...] | list[str] = (),
     code: Sequence[types.ModuleType] = (),
 ) -> Callable[[Callable[..., Any]], UdfDefinition]: ...
 
@@ -2061,6 +2073,7 @@ def udf(
     gpu: bool = False,
     conda: tuple[str, ...] | list[str] = (),
     conda_channels: tuple[str, ...] | list[str] = (),
+    apt: tuple[str, ...] | list[str] = (),
     code: Sequence[types.ModuleType] = (),
 ):
     """Prepare a Python function or class for remote Function registration.
@@ -2150,6 +2163,12 @@ def udf(
         Conda packages for the remote environment, instead of ``pip``.
     conda_channels : sequence of str, optional
         Conda channels in priority order; requires ``conda``.
+    apt : sequence of str, optional
+        Debian packages (``"name"`` or ``"name=version"``) added to the remote
+        image before the Python environment, for shared libraries pip and
+        conda cannot provide, such as FFmpeg's for ``torchcodec``. Packages
+        are unpacked without running their maintainer scripts. Works with
+        ``pip`` or ``conda``; requires image execution.
     env : mapping of str to str, optional
         Environment variables included in the Function definition. Not for
         credentials -- these are ordinary configuration, stored with the
@@ -2219,6 +2238,7 @@ def udf(
             gpu=gpu,
             conda=tuple(conda),
             conda_channels=tuple(conda_channels),
+            apt=tuple(apt),
             code=tuple(code),
         )
 
diff --git a/python/python/tests/test_first_class_function_slice2.py b/python/python/tests/test_first_class_function_slice2.py
index 0e8aca4e9..562a90eb4 100644
--- a/python/python/tests/test_first_class_function_slice2.py
+++ b/python/python/tests/test_first_class_function_slice2.py
@@ -494,6 +494,30 @@ def test_udf_conda_environment():
         udf(name="channels", conda_channels=["conda-forge"])(lambda value: value)
 
 
+def test_udf_apt_system_packages():
+    @udf(pip=["torchcodec"], apt=["libavutil58", "libavcodec60", "libavutil58"])
+    def decode(value: float) -> float:
+        return value
+
+    request = json.loads(decode.registration_request.to_canonical_json())
+    assert request["runtime"]["environment"] == {
+        "kind": "pip",
+        "packages": ["torchcodec"],
+        "system_packages": ["libavcodec60", "libavutil58"],
+    }
+
+    @udf(conda=["numpy"], apt=["libsndfile1"])
+    def conda_decode(value: float) -> float:
+        return value
+
+    request = json.loads(conda_decode.registration_request.to_canonical_json())
+    assert request["runtime"]["environment"]["system_packages"] == ["libsndfile1"]
+    pip_request = json.loads(normalize_score.registration_request.to_canonical_json())
+    assert "system_packages" not in pip_request["runtime"]["environment"]
+    with pytest.raises(ValueError, match="trimmed"):
+        udf(name="padded", apt=[" libsndfile1"])(lambda value: value)
+
+
 def test_udf_gpu_marker_uses_gpu_runtime():
     @udf(pip=["cupy-cuda12x"], gpu=True)
     def double_on_gpu(value: int) -> int:
diff --git a/rust/lancedb/src/function.rs b/rust/lancedb/src/function.rs
index db93f0071..128a7efdf 100644
--- a/rust/lancedb/src/function.rs
+++ b/rust/lancedb/src/function.rs
@@ -224,6 +224,10 @@ pub struct PythonEnvironmentSpec {
     pub modules: Vec<String>,
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub image: Option<String>,
+    /// Debian packages (`name` or `name=version`) added to the Function's
+    /// image before its Python environment is installed.
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
+    pub system_packages: Vec<String>,
 }
 
 /// Reproducible Python runtime definition understood by Sophon.
@@ -253,6 +257,7 @@ pub enum PythonRuntimeSpec {
     ///         path: None,
     ///         modules: Vec::new(),
     ///         image: None,
+    ///         system_packages: Vec::new(),
     ///     },
     ///     env: BTreeMap::new(),
     /// };
@@ -938,6 +943,27 @@ mod conda_environment_tests {
         assert!(!serde_json::to_string(&pip).unwrap().contains("channels"));
     }
 
+    #[test]
+    fn system_packages_round_trip_and_stay_absent_when_empty() {
+        let apt: PythonEnvironmentSpec = serde_json::from_str(
+            r#"{"kind":"pip","packages":["torchcodec"],"system_packages":["libavutil58"]}"#,
+        )
+        .unwrap();
+        assert_eq!(apt.system_packages, ["libavutil58"]);
+        assert!(
+            serde_json::to_string(&apt)
+                .unwrap()
+                .contains(r#""system_packages":["libavutil58"]"#)
+        );
+        let pip: PythonEnvironmentSpec =
+            serde_json::from_str(r#"{"kind":"pip","packages":["numpy"]}"#).unwrap();
+        assert!(
+            !serde_json::to_string(&pip)
+                .unwrap()
+                .contains("system_packages")
+        );
+    }
+
     #[test]
     fn gpu_python_runtime_marker_round_trips_and_validates() {
         let runtime: PythonRuntimeSpec = serde_json::from_str(