diff --git a/src/internal/reflectlite/value.go b/src/internal/reflectlite/value.go
index 0cccfe9d8..31015cbd2 100644
--- a/src/internal/reflectlite/value.go
+++ b/src/internal/reflectlite/value.go
@@ -1686,12 +1686,6 @@ type funcHeader struct {
 	Code    unsafe.Pointer
 }
 
-type SliceHeader struct {
-	Data uintptr
-	Len  intw
-	Cap  intw
-}
-
 // Slice header that matches the underlying structure. Used for when we switch
 // to a precise GC, which needs to know exactly where pointers live.
 type sliceHeader struct {
@@ -1700,11 +1694,6 @@ type sliceHeader struct {
 	cap  uintptr
 }
 
-type StringHeader struct {
-	Data uintptr
-	Len  intw
-}
-
 // Like sliceHeader, this type is used internally to make sure pointer and
 // non-pointer fields match those of actual strings.
 type stringHeader struct {
@@ -1716,9 +1705,7 @@ type stringHeader struct {
 // See https://github.com/tinygo-org/tinygo/pull/4156
 // and https://github.com/tinygo-org/tinygo/issues/1284.
 var (
-	_ [unsafe.Sizeof([]byte{})]byte = [unsafe.Sizeof(SliceHeader{})]byte{}
 	_ [unsafe.Sizeof([]byte{})]byte = [unsafe.Sizeof(sliceHeader{})]byte{}
-	_ [unsafe.Sizeof("")]byte       = [unsafe.Sizeof(StringHeader{})]byte{}
 	_ [unsafe.Sizeof("")]byte       = [unsafe.Sizeof(stringHeader{})]byte{}
 )
 
diff --git a/src/internal/reflectlite/intw.go b/src/reflect/intw.go
similarity index 92%
rename from src/internal/reflectlite/intw.go
rename to src/reflect/intw.go
index 4dd197cef..20fbd4341 100644
--- a/src/internal/reflectlite/intw.go
+++ b/src/reflect/intw.go
@@ -1,6 +1,6 @@
 //go:build !avr
 
-package reflectlite
+package reflect
 
 // intw is an integer type, used in places where an int is typically required,
 // except architectures where the size of an int != word size.
diff --git a/src/internal/reflectlite/intw_avr.go b/src/reflect/intw_avr.go
similarity index 92%
rename from src/internal/reflectlite/intw_avr.go
rename to src/reflect/intw_avr.go
index 24b437777..8f294eeee 100644
--- a/src/internal/reflectlite/intw_avr.go
+++ b/src/reflect/intw_avr.go
@@ -1,6 +1,6 @@
 //go:build avr
 
-package reflectlite
+package reflect
 
 // intw is an integer type, used in places where an int is typically required,
 // except architectures where the size of an int != word size.
diff --git a/src/internal/reflectlite/intw_test.go b/src/reflect/intw_test.go
similarity index 97%
rename from src/internal/reflectlite/intw_test.go
rename to src/reflect/intw_test.go
index b235b88f4..1014a9ae4 100644
--- a/src/internal/reflectlite/intw_test.go
+++ b/src/reflect/intw_test.go
@@ -1,6 +1,6 @@
 //go:build !avr
 
-package reflectlite_test
+package reflect_test
 
 import (
 	"reflect"
diff --git a/src/reflect/value.go b/src/reflect/value.go
index 26f3657cd..fe41f2d18 100644
--- a/src/reflect/value.go
+++ b/src/reflect/value.go
@@ -226,3 +226,24 @@ func (v Value) Recv() (x Value, ok bool) {
 func NewAt(typ Type, p unsafe.Pointer) Value {
 	panic("unimplemented: reflect.New()")
 }
+
+// Deprecated: Use unsafe.Slice or unsafe.SliceData instead.
+type SliceHeader struct {
+	Data uintptr
+	Len  intw
+	Cap  intw
+}
+
+// Deprecated: Use unsafe.String or unsafe.StringData instead.
+type StringHeader struct {
+	Data uintptr
+	Len  intw
+}
+
+// Verify SliceHeader and StringHeader sizes.
+// See https://github.com/tinygo-org/tinygo/pull/4156
+// and https://github.com/tinygo-org/tinygo/issues/1284.
+var (
+	_ [unsafe.Sizeof([]byte{})]byte = [unsafe.Sizeof(SliceHeader{})]byte{}
+	_ [unsafe.Sizeof("")]byte       = [unsafe.Sizeof(StringHeader{})]byte{}
+)