diff --git a/cidre/src/av/audio/session/route.rs b/cidre/src/av/audio/session/route.rs
index 20115fcf..313bb3fb 100644
--- a/cidre/src/av/audio/session/route.rs
+++ b/cidre/src/av/audio/session/route.rs
@@ -1,4 +1,4 @@
-use crate::{av, define_obj_type, ns, objc};
+use crate::{arc, av, define_obj_type, ns, objc};
 
 define_obj_type!(
     /// The location of a data source on an iOS device.
@@ -106,11 +106,11 @@ define_obj_type!(
 impl ChannelDesc {
     /// A human-readable name for the channel.
     #[objc::msg_send(channelName)]
-    pub fn channel_name(&self) -> &ns::String;
+    pub fn channel_name(&self) -> arc::R<ns::String>;
 
     /// The UID (unique identifier) of the port owning the channel
     #[objc::msg_send(owningPortUID)]
-    pub fn owning_port_uid(&self) -> &ns::String;
+    pub fn owning_port_uid(&self) -> arc::R<ns::String>;
 
     #[objc::msg_send(channelNumber)]
     pub fn channel_number(&self) -> usize;
@@ -129,11 +129,11 @@ impl DataSrcDesc {
     // TODO: verify leak
     /// System-assigned ID for the data source.
     #[objc::msg_send(dataSourceID)]
-    pub fn data_src_id(&self) -> &ns::String;
+    pub fn data_src_id(&self) -> arc::R<ns::String>;
 
     /// Human-readable name for the data source.
     #[objc::msg_send(dataSourceName)]
-    pub fn data_source_name(&self) -> &ns::String;
+    pub fn data_source_name(&self) -> arc::R<ns::String>;
 
     /// Location and orientation can be used to distinguish between multiple data sources
     /// belonging to a single port.  For example, in the case of a port of type
@@ -142,21 +142,21 @@ impl DataSrcDesc {
     ///
     /// Will be nil for data sources for which the location is not known.
     #[objc::msg_send(location)]
-    pub fn location(&self) -> Option<&Location>;
+    pub fn location(&self) -> Option<arc::R<Location>>;
 
     /// Describes the orientation of a data source. Will be nil for data sources for which the
     /// orientation is not known.
     #[objc::msg_send(orientation)]
-    pub fn orientation(&self) -> Option<&Orientation>;
+    pub fn orientation(&self) -> Option<arc::R<Orientation>>;
 
     #[objc::msg_send(supportedPolarPatterns)]
-    pub fn supported_polar_patterns(&self) -> Option<&ns::Array<PolarPattern>>;
+    pub fn supported_polar_patterns(&self) -> Option<arc::R<ns::Array<PolarPattern>>>;
 
     #[objc::msg_send(selectedPolarPattern)]
-    pub fn selected_polar_pattern(&self) -> Option<&PolarPattern>;
+    pub fn selected_polar_pattern(&self) -> Option<arc::R<PolarPattern>>;
 
     #[objc::msg_send(preferredPolarPattern)]
-    pub fn preferred_polar_pattern(&self) -> Option<&PolarPattern>;
+    pub fn preferred_polar_pattern(&self) -> Option<arc::R<PolarPattern>>;
 
     // - (BOOL)setPreferredPolarPattern:(nullable AVAudioSessionPolarPattern)pattern error:(NSError **)outError
 
@@ -189,13 +189,13 @@ define_obj_type!(
 
 impl PortDesc {
     #[objc::msg_send(portType)]
-    pub fn port_type(&self) -> &av::AudioSessionPort;
+    pub fn port_type(&self) -> arc::R<av::AudioSessionPort>;
 
     #[objc::msg_send(portName)]
-    pub fn port_name(&self) -> &ns::String;
+    pub fn port_name(&self) -> arc::R<ns::String>;
 
     #[objc::msg_send(UID)]
-    pub fn uid(&self) -> &ns::String;
+    pub fn uid(&self) -> arc::R<ns::String>;
 
     /// This property's value will be true if the associated hardware port has built-in
     /// processing for two-way voice communication.
@@ -206,16 +206,16 @@ impl PortDesc {
     pub fn is_spatial_audio_enabled(&self) -> bool;
 
     #[objc::msg_send(channels)]
-    pub fn channels(&self) -> Option<&ns::Array<ChannelDesc>>;
+    pub fn channels(&self) -> Option<arc::R<ns::Array<ChannelDesc>>>;
 
     #[objc::msg_send(dataSources)]
-    pub fn data_srcs(&self) -> Option<&ns::Array<DataSrcDesc>>;
+    pub fn data_srcs(&self) -> Option<arc::R<ns::Array<DataSrcDesc>>>;
 
     #[objc::msg_send(selectedDataSource)]
-    pub fn selected_data_src(&self) -> Option<&DataSrcDesc>;
+    pub fn selected_data_src(&self) -> Option<arc::R<DataSrcDesc>>;
 
     #[objc::msg_send(preferredDataSource)]
-    pub fn preferred_data_src(&self) -> Option<&DataSrcDesc>;
+    pub fn preferred_data_src(&self) -> Option<arc::R<DataSrcDesc>>;
 
     #[objc::msg_send(setPreferredDataSource:error:)]
     pub unsafe fn set_preferred_data_src_err<'ear>(
@@ -236,8 +236,8 @@ define_obj_type!(
 
 impl RouteDesc {
     #[objc::msg_send(inputs)]
-    pub fn inputs(&self) -> &ns::Array<PortDesc>;
+    pub fn inputs(&self) -> arc::R<ns::Array<PortDesc>>;
 
     #[objc::msg_send(outputs)]
-    pub fn outputs(&self) -> &ns::Array<PortDesc>;
+    pub fn outputs(&self) -> arc::R<ns::Array<PortDesc>>;
 }
diff --git a/cidre/src/mlc/layer.rs b/cidre/src/mlc/layer.rs
index a87b9098..5a87f07c 100644
--- a/cidre/src/mlc/layer.rs
+++ b/cidre/src/mlc/layer.rs
@@ -1,12 +1,15 @@
-use crate::{define_obj_type, mlc, ns, objc};
+use crate::{arc, define_obj_type, mlc, ns, objc};
 
-define_obj_type!(pub Layer(ns::Id));
+define_obj_type!(
+    #[doc(alias = "MLCLayer")]
+    pub Layer(ns::Id)
+);
 impl Layer {
     #[objc::msg_send(layerID)]
     pub fn layer_id(&self) -> usize;
 
     #[objc::msg_send(label)]
-    pub fn label(&self) -> &ns::String;
+    pub fn label(&self) -> arc::R<ns::String>;
 
     #[objc::msg_send(setLabel:)]
     pub fn set_label(&mut self, val: &ns::String);
diff --git a/cidre/src/mlc/tensor.rs b/cidre/src/mlc/tensor.rs
index 61b86ddd..efcdfde9 100644
--- a/cidre/src/mlc/tensor.rs
+++ b/cidre/src/mlc/tensor.rs
@@ -11,13 +11,13 @@ impl Tensor {
     pub fn tensor_id(&self) -> usize;
 
     #[objc::msg_send(descriptor)]
-    pub fn desc(&self) -> &mlc::TensorDesc;
+    pub fn desc(&self) -> arc::R<mlc::TensorDesc>;
 
     #[objc::msg_send(data)]
-    pub fn data(&self) -> Option<&ns::Data>;
+    pub fn data(&self) -> Option<arc::R<ns::Data>>;
 
     #[objc::msg_send(label)]
-    pub fn label(&self) -> &ns::String;
+    pub fn label(&self) -> arc::R<ns::String>;
 
     #[objc::msg_send(setLabel:)]
     pub fn set_label(&mut self, val: &ns::String);
diff --git a/cidre/src/mtl/compute_command_encoder.rs b/cidre/src/mtl/compute_command_encoder.rs
index 0f976bbc..406d3615 100644
--- a/cidre/src/mtl/compute_command_encoder.rs
+++ b/cidre/src/mtl/compute_command_encoder.rs
@@ -1,6 +1,9 @@
 use crate::{define_mtl, define_obj_type, mtl, ns, objc};
 
-define_obj_type!(pub ComputeCmdEncoder(mtl::CmdEncoder));
+define_obj_type!(
+    #[doc(alias = "MTLComputeCommandEncoder")]
+    pub ComputeCmdEncoder(mtl::CmdEncoder)
+);
 
 impl ComputeCmdEncoder {
     define_mtl!(
diff --git a/cidre/src/ns/range.rs b/cidre/src/ns/range.rs
index 56d9de99..61ce58c6 100644
--- a/cidre/src/ns/range.rs
+++ b/cidre/src/ns/range.rs
@@ -10,13 +10,13 @@ pub struct Range {
 
 impl Range {
     #[inline]
-    pub fn new(loc: ns::UInteger, len: ns::UInteger) -> Self {
+    pub const fn new(loc: ns::UInteger, len: ns::UInteger) -> Self {
         Self { loc, len }
     }
 
     #[doc(alias = "NSMaxRange")]
     #[inline]
-    pub fn max(&self) -> ns::UInteger {
+    pub const fn max(&self) -> ns::UInteger {
         self.loc + self.len
     }
 
@@ -46,7 +46,7 @@ impl Range {
     /// ```
     #[doc(alias = "NSLocationInRange")]
     #[inline]
-    pub fn loc_in_range(location: ns::UInteger, range: &Self) -> bool {
+    pub const fn loc_in_range(location: ns::UInteger, range: &Self) -> bool {
         location >= range.loc && (location - range.loc) < range.len
     }
 
@@ -58,7 +58,7 @@ impl Range {
     /// assert!(!a.contains(10));
     /// ```
     #[inline]
-    pub fn contains(&self, location: ns::UInteger) -> bool {
+    pub const fn contains(&self, location: ns::UInteger) -> bool {
         Range::loc_in_range(location, self)
     }
 }