diff --git a/mercurial/dirstate.py b/mercurial/dirstate.py
--- a/mercurial/dirstate.py
+++ b/mercurial/dirstate.py
@@ -1200,9 +1200,6 @@
 
         if rustmod is None:
             use_rust = False
-        elif self._checkcase:
-            # Case-insensitive filesystems are not handled yet
-            use_rust = False
         elif subrepos:
             use_rust = False
         elif sparse.enabled:
diff --git a/rust/hg-core/src/dirstate/dirstate_map.rs b/rust/hg-core/src/dirstate/dirstate_map.rs
--- a/rust/hg-core/src/dirstate/dirstate_map.rs
+++ b/rust/hg-core/src/dirstate/dirstate_map.rs
@@ -8,10 +8,7 @@
 use crate::{
     dirstate::{parsers::PARENT_SIZE, EntryState, SIZE_FROM_OTHER_PARENT},
     pack_dirstate, parse_dirstate,
-    utils::{
-        files::normalize_case,
-        hg_path::{HgPath, HgPathBuf},
-    },
+    utils::hg_path::{HgPath, HgPathBuf},
     CopyMap, DirsMultiset, DirstateEntry, DirstateError, DirstateMapError,
     DirstateParents, DirstateParseError, FastHashMap, StateMap,
 };
@@ -135,7 +132,12 @@
         }
 
         if let Some(ref mut file_fold_map) = self.file_fold_map {
-            file_fold_map.remove(&normalize_case(filename));
+            match filename.canonical_name() {
+                Ok(canonical_name) => {
+                    file_fold_map.remove(&canonical_name);
+                }
+                Err(_) => {}
+            }
         }
         self.state_map.insert(
             filename.to_owned(),
@@ -172,7 +174,12 @@
             }
         }
         if let Some(ref mut file_fold_map) = self.file_fold_map {
-            file_fold_map.remove(&normalize_case(filename));
+            match filename.canonical_name() {
+                Ok(canonical_name) => {
+                    file_fold_map.remove(&canonical_name);
+                }
+                Err(_) => {}
+            }
         }
         self.get_non_normal_other_parent_entries()
             .0
@@ -399,8 +406,14 @@
         for (filename, DirstateEntry { state, .. }) in self.state_map.borrow()
         {
             if *state == EntryState::Removed {
-                new_file_fold_map
-                    .insert(normalize_case(filename), filename.to_owned());
+                match filename.canonical_name() {
+                    Ok(canonical_filename) => {
+                        new_file_fold_map
+                            .insert(filename.to_owned(), canonical_filename);
+                    }
+                    Err(_) => {
+                    }
+                }
             }
         }
         self.file_fold_map = Some(new_file_fold_map);
diff --git a/rust/hg-core/src/dirstate/status.rs b/rust/hg-core/src/dirstate/status.rs
--- a/rust/hg-core/src/dirstate/status.rs
+++ b/rust/hg-core/src/dirstate/status.rs
@@ -786,8 +786,8 @@
         .filter_map(|(filename, entry)| -> Option<IoResult<_>> {
             // Report ignored items in the dmap as long as they are not
             // under a symlink directory.
-            if path_auditor.check(filename) {
-                // TODO normalize for case-insensitive filesystems
+            // Only consider items found under the proper name
+            if filename.check_name() && path_auditor.check(filename) {
                 let buf = match hg_path_to_path_buf(filename) {
                     Ok(x) => x,
                     Err(e) => return Some(Err(e.into())),
diff --git a/rust/hg-core/src/lib.rs b/rust/hg-core/src/lib.rs
--- a/rust/hg-core/src/lib.rs
+++ b/rust/hg-core/src/lib.rs
@@ -26,11 +26,10 @@
 pub mod operations;
 pub mod utils;
 
-// Remove this to see (potential) non-artificial compile failures. MacOS
-// *should* compile, but fail to compile tests for example as of 2020-03-06
-#[cfg(not(target_os = "linux"))]
+// Remove this to see (potential) non-artificial compile failures.
+#[cfg(not(any(target_os = "linux", target_os = "macos")))]
 compile_error!(
-    "`hg-core` has only been tested on Linux and will most \
+    "`hg-core` has only been tested on Linux and macOS and will most \
      likely not behave correctly on other platforms."
 );
 
diff --git a/rust/hg-core/src/utils/hg_path.rs b/rust/hg-core/src/utils/hg_path.rs
--- a/rust/hg-core/src/utils/hg_path.rs
+++ b/rust/hg-core/src/utils/hg_path.rs
@@ -6,6 +6,7 @@
 // GNU General Public License version 2 or any later version.
 
 use std::borrow::Borrow;
+use std::fs::canonicalize;
 use std::ffi::{OsStr, OsString};
 use std::fmt;
 use std::ops::Deref;
@@ -183,6 +184,32 @@
             &self.inner[..]
         })
     }
+    pub fn canonical_name(&self) -> Result<HgPathBuf, HgPathError> {
+        match canonicalize(&hg_path_to_path_buf(&self)?) {
+            Ok(canonical_path) => {
+                let canonical_name = os_string_to_hg_path_buf(
+                    &canonical_path.file_name().unwrap()
+                )?;
+                Ok(self.parent().join(&canonical_name))
+            }
+            Err(_) => Err(HgPathError::NotFsCompliant(self.to_hg_path_buf())),
+        }
+    }
+    pub fn check_name(&self) -> bool {
+        let path;
+
+        match hg_path_to_path_buf(&self) {
+            Ok(p) => path = p,
+            Err(_) => return true,
+        }
+
+        match canonicalize(&path) {
+            Ok(canonical_path) => {
+                canonical_path.file_name() == path.file_name()
+            }
+            Err(_) => true
+        }
+    }
     /// Returns a tuple of slices `(base, filename)` resulting from the split
     /// at the rightmost `/`, if any.
     ///
diff --git a/rust/hg-cpython/src/dirstate/dirstate_map.rs b/rust/hg-cpython/src/dirstate/dirstate_map.rs
--- a/rust/hg-cpython/src/dirstate/dirstate_map.rs
+++ b/rust/hg-cpython/src/dirstate/dirstate_map.rs
@@ -350,8 +350,8 @@
         {
             dict.set_item(
                 py,
-                key.as_bytes().to_vec(),
-                value.as_bytes().to_vec(),
+                PyBytes::new(py, key.as_bytes()).into_object(),
+                PyBytes::new(py, value.as_bytes()).into_object(),
             )?;
         }
         Ok(dict)