diff --git a/src/allocator/boxed.rs b/src/allocator/boxed.rs
new file mode 100644
index 00000000..7fa4cf9a
--- /dev/null
+++ b/src/allocator/boxed.rs
@@ -0,0 +1,19 @@
+use {
+    super::{
+        Allocator,
+        like::Like,
+        requirement::Requirement
+    },
+    core::marker::PhantomData
+};
+
+pub struct Box<Item: ?Sized, Heap: Allocator + Requirement>(PhantomData<(Heap, Item)>);
+
+impl<Item: ?Sized, Heap: Allocator + Requirement> Like for Box<Item, Heap> {
+    #[cfg(not(feature = "allocator-api"))]
+    type Type = alloc::boxed::Box<Item>;
+    #[cfg(all(feature = "allocator-api", not(feature = "allocator-api2")))]
+    type Type = alloc::boxed::Box<Item, Heap>;
+    #[cfg(feature = "allocator-api2")]
+    type Type = allocator_api2::boxed::Box<Item, Heap>;
+}
diff --git a/src/allocator/global.rs b/src/allocator/global.rs
new file mode 100644
index 00000000..67af50c6
--- /dev/null
+++ b/src/allocator/global.rs
@@ -0,0 +1,7 @@
+#[cfg(not(feature = "allocator-api"))]
+#[derive(Clone)]
+pub struct Global;
+#[cfg(all(feature = "allocator-api", not(feature = "allocator-api2")))]
+pub use alloc::alloc::Global;
+#[cfg(feature = "allocator-api2")]
+pub use allocator_api2::alloc::Global;
diff --git a/src/allocator/base.rs b/src/allocator/implementations/base.rs
similarity index 94%
rename from src/allocator/base.rs
rename to src/allocator/implementations/base.rs
index 76ec54e8..996586fd 100644
--- a/src/allocator/base.rs
+++ b/src/allocator/implementations/base.rs
@@ -1,5 +1,8 @@
 use {
-    super::Allocator,
+    super::super::{
+        Allocator,
+        global::Global
+    },
     alloc::alloc::{
         alloc,
         dealloc,
@@ -11,9 +14,6 @@ use {
     }
 };
 
-#[derive(Clone)]
-pub struct Global;
-
 impl Allocator for Global {
     #[inline]
     fn allocate(&self, layout: Layout) -> Option<NonNull<[u8]>> {
diff --git a/src/allocator/external.rs b/src/allocator/implementations/external.rs
similarity index 96%
rename from src/allocator/external.rs
rename to src/allocator/implementations/external.rs
index 635a8697..72083f23 100644
--- a/src/allocator/external.rs
+++ b/src/allocator/implementations/external.rs
@@ -1,5 +1,5 @@
 use {
-    super::Allocator,
+    super::super::Allocator,
     allocator_api2::alloc::Allocator as External,
     core::{
         alloc::Layout,
diff --git a/src/allocator/implementations/mod.rs b/src/allocator/implementations/mod.rs
new file mode 100644
index 00000000..59ab2e1e
--- /dev/null
+++ b/src/allocator/implementations/mod.rs
@@ -0,0 +1,6 @@
+#[cfg(not(feature = "allocator-api"))]
+mod base;
+#[cfg(feature = "allocator-api2")]
+mod external;
+#[cfg(all(feature = "allocator-api", not(feature = "allocator-api2")))]
+mod native;
diff --git a/src/allocator/native.rs b/src/allocator/implementations/native.rs
similarity index 96%
rename from src/allocator/native.rs
rename to src/allocator/implementations/native.rs
index 77603616..70ef0866 100644
--- a/src/allocator/native.rs
+++ b/src/allocator/implementations/native.rs
@@ -1,5 +1,5 @@
 use {
-    super::Allocator,
+    super::super::Allocator,
     alloc::alloc::Allocator as Native,
     core::{
         alloc::Layout,
diff --git a/src/allocator/like.rs b/src/allocator/like.rs
new file mode 100644
index 00000000..593bdbef
--- /dev/null
+++ b/src/allocator/like.rs
@@ -0,0 +1,3 @@
+pub trait Like {
+    type Type;
+}
diff --git a/src/allocator/mod.rs b/src/allocator/mod.rs
index 5e67a3a8..074f7190 100644
--- a/src/allocator/mod.rs
+++ b/src/allocator/mod.rs
@@ -1,43 +1,16 @@
-#[cfg(not(feature = "allocator-api"))]
-mod base;
-#[cfg(feature = "allocator-api2")]
-mod external;
-#[cfg(all(feature = "allocator-api", not(feature = "allocator-api2")))]
-mod native;
+pub mod boxed;
+pub mod global;
+mod implementations;
+pub mod like;
 pub mod proxy;
+mod requirement;
+pub mod vec;
 
 use core::{
     alloc::Layout,
     ptr::NonNull
 };
 
-#[cfg(not(feature = "allocator-api"))]
-#[rustfmt::skip]
-pub use {
-    alloc::{
-        boxed::Box,
-        vec::Vec,
-        vec
-    },
-    base::Global
-};
-#[cfg(feature = "allocator-api2")]
-#[rustfmt::skip]
-pub use allocator_api2::{
-    alloc::Global,
-    boxed::Box,
-    vec::Vec,
-    vec
-};
-#[cfg(all(feature = "allocator-api", not(feature = "allocator-api2")))]
-#[rustfmt::skip]
-pub use alloc::{
-    alloc::Global,
-    boxed::Box,
-    vec::Vec,
-    vec
-};
-
 pub trait Allocator {
     fn allocate(&self, layout: Layout) -> Option<NonNull<[u8]>>;
     unsafe fn deallocate(&self, pointer: NonNull<u8>, layout: Layout);
diff --git a/src/allocator/requirement.rs b/src/allocator/requirement.rs
new file mode 100644
index 00000000..23529e2c
--- /dev/null
+++ b/src/allocator/requirement.rs
@@ -0,0 +1,6 @@
+#[cfg(all(feature = "allocator-api", not(feature = "allocator-api2")))]
+pub use alloc::alloc::Allocator as Requirement;
+#[cfg(feature = "allocator-api2")]
+pub use allocator_api2::alloc::Allocator as Requirement;
+#[cfg(not(feature = "allocator-api"))]
+pub use core::marker::Sized as Requirement;
diff --git a/src/allocator/vec.rs b/src/allocator/vec.rs
new file mode 100644
index 00000000..a7801449
--- /dev/null
+++ b/src/allocator/vec.rs
@@ -0,0 +1,23 @@
+#[cfg(not(feature = "allocator-api2"))]
+pub use alloc::vec;
+#[cfg(feature = "allocator-api2")]
+pub use allocator_api2::vec;
+use {
+    super::{
+        Allocator,
+        like::Like,
+        requirement::Requirement
+    },
+    core::marker::PhantomData
+};
+
+pub struct Vec<Item, Heap: Allocator + Requirement>(PhantomData<(Heap, Item)>);
+
+impl<Item, Heap: Allocator + Requirement> Like for Vec<Item, Heap> {
+    #[cfg(not(feature = "allocator-api"))]
+    type Type = alloc::vec::Vec<Item>;
+    #[cfg(all(feature = "allocator-api", not(feature = "allocator-api2")))]
+    type Type = alloc::vec::Vec<Item, Heap>;
+    #[cfg(feature = "allocator-api2")]
+    type Type = allocator_api2::vec::Vec<Item, Heap>;
+}
diff --git a/src/conversions.rs b/src/conversions.rs
index 13cde585..4f60800a 100644
--- a/src/conversions.rs
+++ b/src/conversions.rs
@@ -4,7 +4,8 @@ use {
         Box,
         Global,
         SmallVec,
-        Vec
+        Vec,
+        allocator::like::Like
     },
     core::{
         mem::ManuallyDrop,
@@ -17,7 +18,7 @@ impl<T: Clone, const N: usize> From<&[T]> for SmallVec<T, N, Global> {
     fn from(slice: &[T]) -> Self {
         if slice.len() > Self::inline_size() {
             // Standard Rust vectors are already specialized.
-            Self::from_vec(Vec::from(slice))
+            Self::from_vec(<Vec<T, Global> as Like>::Type::from(slice))
         } else {
             // SAFETY: The precondition is checked in the initial comparison
             // above.
@@ -62,7 +63,7 @@ impl<T, const N: usize, const M: usize> From<[T; M]> for SmallVec<T, N, Global>
         if M > N {
             // If M > N, we'd have to heap allocate anyway,
             // so delegate for Vec for the allocation.
-            Self::from(Vec::from(array))
+            Self::from(<Vec<T, Global> as Like>::Type::from(array))
         } else {
             // M <= N
             let mut this = Self::new();
@@ -97,17 +98,17 @@ impl<T, const N: usize, const M: usize, A: Allocator> TryFrom<SmallVec<T, N, A>>
     }
 }
 
-impl<T, const N: usize> From<Vec<T>> for SmallVec<T, N, Global> {
-    fn from(array: Vec<T>) -> Self {
+impl<T, const N: usize> From<<Vec<T, Global> as Like>::Type> for SmallVec<T, N, Global> {
+    fn from(array: <Vec<T, Global> as Like>::Type) -> Self {
         Self::from_vec(array)
     }
 }
 
-impl<T, const N: usize, A: Allocator> From<SmallVec<T, N, A>> for Vec<T> {
+impl<T, const N: usize, A: Allocator> From<SmallVec<T, N, A>> for <Vec<T, Global> as Like>::Type {
     fn from(this: SmallVec<T, N, A>) -> Self {
         let (length, on_heap) = this.length.parts();
         if !on_heap {
-            let mut vec = Vec::with_capacity(length);
+            let mut vec = <Vec<T, Global> as Like>::Type::with_capacity(length);
             let this = ManuallyDrop::new(this);
             // SAFETY: we create a new vector with sufficient capacity, copy our
             // elements into it to transfer ownership and then set
@@ -129,14 +130,14 @@ impl<T, const N: usize, A: Allocator> From<SmallVec<T, N, A>> for Vec<T> {
             // - the allocation is not larger than `isize::MAX`
             unsafe {
                 let (ptr, cap) = this.raw.heap;
-                Vec::from_raw_parts(ptr.as_ptr(), length, cap)
+                <Vec<T, Global> as Like>::Type::from_raw_parts(ptr.as_ptr(), length, cap)
             }
         }
     }
 }
 
-impl<T, const N: usize, A: Allocator> From<SmallVec<T, N, A>> for Box<[T]> {
+impl<T, const N: usize, A: Allocator> From<SmallVec<T, N, A>> for <Box<[T], Global> as Like>::Type {
     fn from(this: SmallVec<T, N, A>) -> Self {
-        Vec::from(this).into_boxed_slice()
+        <Vec<T, Global> as Like>::Type::from(this).into_boxed_slice()
     }
 }
diff --git a/src/iterators/mod.rs b/src/iterators/mod.rs
index 40585e0c..78953514 100644
--- a/src/iterators/mod.rs
+++ b/src/iterators/mod.rs
@@ -1,7 +1,6 @@
 pub mod drain;
 pub mod extractif;
 pub mod intoiter;
-pub mod splice;
-
 #[cfg(feature = "rayon")]
 mod rayon;
+pub mod splice;
diff --git a/src/lib.rs b/src/lib.rs
index 9f391826..cb4c3ff7 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -58,10 +58,13 @@ use std::io;
 use {
     allocator::{
         Allocator,
-        Box,
-        Global,
-        Vec,
-        vec
+        boxed::Box,
+        global::Global,
+        like::Like,
+        vec::{
+            Vec,
+            vec
+        }
     },
     core::{
         alloc::Layout,
@@ -220,7 +223,7 @@ impl<T, const N: usize> SmallVec<T, N, Global> {
     }
 
     #[inline]
-    pub fn from_vec(vec: Vec<T>) -> Self {
+    pub fn from_vec(vec: <Vec<T, Global> as Like>::Type) -> Self {
         if vec.capacity() == 0 {
             return Self::new();
         }
@@ -757,7 +760,8 @@ impl<T, const N: usize, A: Allocator> SmallVec<T, N, A> {
                 let (ptr, capacity) = self.raw.heap;
                 copy_nonoverlapping(ptr.as_ptr(), self.raw.as_mut_ptr_inline(), length);
                 self.length.set_location::<false>();
-                self.allocator.deallocate(
+                Allocator::deallocate(
+                    &self.allocator,
                     ptr.cast(),
                     Layout::from_size_align_unchecked(capacity * size_of::<T>(), align_of::<T>())
                 );
@@ -791,7 +795,8 @@ impl<T, const N: usize, A: Allocator> SmallVec<T, N, A> {
                     let (ptr, capacity) = self.raw.heap;
                     copy_nonoverlapping(ptr.as_ptr(), self.raw.as_mut_ptr_inline(), length);
                     self.length.set_location::<false>();
-                    self.allocator.deallocate(
+                    Allocator::deallocate(
+                        &self.allocator,
                         ptr.cast(),
                         Layout::from_size_align_unchecked(
                             capacity * size_of::<T>(),
@@ -980,13 +985,13 @@ impl<T, const N: usize, A: Allocator> SmallVec<T, N, A> {
 
     #[inline]
     #[deprecated(since = "2.0.0", note = "use `Into::<Vec<T>>::into` instead")]
-    pub fn into_vec(self) -> Vec<T> {
+    pub fn into_vec(self) -> <Vec<T, Global> as Like>::Type {
         self.into()
     }
 
     #[inline]
     #[deprecated(since = "2.0.0", note = "use `Into::<Box<[T]>>::into` instead")]
-    pub fn into_boxed_slice(self) -> Box<[T]> {
+    pub fn into_boxed_slice(self) -> <Box<[T], Global> as Like>::Type {
         self.into()
     }
 
@@ -1466,7 +1471,8 @@ impl<A: Allocator> Drop for DropDealloc<'_, A> {
     fn drop(&mut self) {
         unsafe {
             if self.size_bytes > 0 {
-                self.allocator.deallocate(
+                Allocator::deallocate(
+                    self.allocator,
                     self.ptr,
                     Layout::from_size_align_unchecked(self.size_bytes, self.align)
                 );
diff --git a/src/rawsmallvec.rs b/src/rawsmallvec.rs
index 0330bc2e..45f21aab 100644
--- a/src/rawsmallvec.rs
+++ b/src/rawsmallvec.rs
@@ -126,8 +126,7 @@ impl<T, const N: usize> RawSmallVec<T, N> {
         let new_ptr = if !was_on_heap {
             // get a fresh allocation
             // `new_layout` has nonzero size.
-            let new_ptr = allocator
-                .allocate(new_layout)
+            let new_ptr = Allocator::allocate(allocator, new_layout)
                 .ok_or(SmallVecError::AllocationError(new_layout))?
                 .cast();
             unsafe { copy_nonoverlapping(ptr, new_ptr.as_ptr(), length) };
@@ -149,9 +148,9 @@ impl<T, const N: usize> RawSmallVec<T, N> {
             // with Layout::array
             unsafe {
                 (if self.heap.1 < new_capacity {
-                    A::grow
+                    <A as Allocator>::grow
                 } else {
-                    A::shrink
+                    <A as Allocator>::shrink
                 })(
                     allocator,
                     NonNull::new(ptr as *mut u8).unwrap(),