diff --git a/fuzzers/src/bin/fuzz-indexing.rs b/fuzzers/src/bin/fuzz-indexing.rs
index 64081aba9..608933016 100644
--- a/fuzzers/src/bin/fuzz-indexing.rs
+++ b/fuzzers/src/bin/fuzz-indexing.rs
@@ -56,7 +56,7 @@ fn main() {
                 Some(path) => TempDir::new_in(path).unwrap(),
                 None => TempDir::new().unwrap(),
             };
-            let index = Index::new("", options, tempdir.path()).unwrap();
+            let index = Index::new(None, options, tempdir.path()).unwrap();
             let indexer_config = IndexerConfig::default();
             let index_documents_config = IndexDocumentsConfig::default();
 
diff --git a/index-scheduler/src/index_mapper/index_map.rs b/index-scheduler/src/index_mapper/index_map.rs
index 6be82e147..cf8288461 100644
--- a/index-scheduler/src/index_mapper/index_map.rs
+++ b/index-scheduler/src/index_mapper/index_map.rs
@@ -103,7 +103,7 @@ impl ReopenableIndex {
                 return Ok(());
             }
             map.unavailable.remove(&self.uuid);
-            map.create("", &self.uuid, path, None, self.enable_mdb_writemap, self.map_size)?;
+            map.create(None, &self.uuid, path, None, self.enable_mdb_writemap, self.map_size)?;
         }
         Ok(())
     }
@@ -167,7 +167,7 @@ impl IndexMap {
     ///
     pub fn create(
         &mut self,
-        name: &str,
+        name: Option<String>,
         uuid: &Uuid,
         path: &Path,
         date: Option<(OffsetDateTime, OffsetDateTime)>,
@@ -297,7 +297,7 @@ impl IndexMap {
 /// Create or open an index in the specified path.
 /// The path *must* exist or an error will be thrown.
 fn create_or_open_index(
-    name: &str,
+    name: Option<String>,
     path: &Path,
     date: Option<(OffsetDateTime, OffsetDateTime)>,
     enable_mdb_writemap: bool,
@@ -312,14 +312,14 @@ fn create_or_open_index(
 
     if let Some((created, updated)) = date {
         Ok(Index::new_with_creation_dates(
-            Some(String::from(name)),
+            name,
             options,
             path,
             created,
             updated,
         )?)
     } else {
-        Ok(Index::new(Some(String::from(name)), options, path)?)
+        Ok(Index::new(name, options, path)?)
     }
 }
 
diff --git a/index-scheduler/src/index_mapper/mod.rs b/index-scheduler/src/index_mapper/mod.rs
index 34e037266..95ddd4145 100644
--- a/index-scheduler/src/index_mapper/mod.rs
+++ b/index-scheduler/src/index_mapper/mod.rs
@@ -182,7 +182,7 @@ impl IndexMapper {
                 // This is very unlikely to happen in practice.
                 // TODO: it would be better to lazily create the index. But we need an Index::open function for milli.
                 let index = self.index_map.write().unwrap().create(
-					&name,
+					Some(name.to_string()),
                     &uuid,
                     &index_path,
                     date,
@@ -372,7 +372,7 @@ impl IndexMapper {
                             let index_path = self.base_path.join(uuid.to_string());
 
                             break index_map.create(
-								name,
+								Some(name.to_string()),
                                 &uuid,
                                 &index_path,
                                 None,
diff --git a/meilitool/src/main.rs b/meilitool/src/main.rs
index 4af5107ff..1cbab32c5 100644
--- a/meilitool/src/main.rs
+++ b/meilitool/src/main.rs
@@ -267,7 +267,7 @@ fn export_a_dump(
     for result in index_mapping.iter(&rtxn)? {
         let (uid, uuid) = result?;
         let index_path = db_path.join("indexes").join(uuid.to_string());
-        let index = Index::new("", EnvOpenOptions::new(), &index_path).with_context(|| {
+        let index = Index::new(None, EnvOpenOptions::new(), &index_path).with_context(|| {
             format!("While trying to open the index at path {:?}", index_path.display())
         })?;
 
diff --git a/milli/examples/index.rs b/milli/examples/index.rs
index 14eb45cf4..466c0a853 100644
--- a/milli/examples/index.rs
+++ b/milli/examples/index.rs
@@ -41,7 +41,7 @@ fn main() -> Result<(), Box<dyn Error>> {
     options.map_size(100 * 1024 * 1024 * 1024); // 100 GB
 
     std::fs::create_dir_all(&index_path).unwrap();
-    let index = Index::new(program_name.as_str(), options, index_path).unwrap();
+    let index = Index::new(Some(program_name), options, index_path).unwrap();
     let mut wtxn = index.write_txn().unwrap();
 
     let config = IndexerConfig::default();
diff --git a/milli/examples/search.rs b/milli/examples/search.rs
index 5c9fe5f07..1b31b8bf5 100644
--- a/milli/examples/search.rs
+++ b/milli/examples/search.rs
@@ -28,7 +28,7 @@ fn main() -> Result<(), Box<dyn Error>> {
     let mut options = EnvOpenOptions::new();
     options.map_size(100 * 1024 * 1024 * 1024); // 100 GB
 
-    let index = Index::new(program_name.as_str(), options, dataset)?;
+    let index = Index::new(Some(program_name), options, dataset)?;
     let txn = index.read_txn()?;
     let mut query = String::new();
     while stdin().read_line(&mut query)? > 0 {
diff --git a/milli/examples/settings.rs b/milli/examples/settings.rs
index bcf50058f..846e3b070 100644
--- a/milli/examples/settings.rs
+++ b/milli/examples/settings.rs
@@ -10,7 +10,7 @@ fn main() {
     let mut options = EnvOpenOptions::new();
     options.map_size(100 * 1024 * 1024 * 1024); // 100 GB
 
-    let index = Index::new("", options, "data_movies.ms").unwrap();
+    let index = Index::new(None, options, "data_movies.ms").unwrap();
     let mut wtxn = index.write_txn().unwrap();
 
     let config = IndexerConfig::default();
diff --git a/milli/src/error.rs b/milli/src/error.rs
index 1aca14d51..6326f696d 100644
--- a/milli/src/error.rs
+++ b/milli/src/error.rs
@@ -469,7 +469,7 @@ fn conditionally_lookup_for_error_message() {
     for (list, suffix) in messages {
         let err = UserError::InvalidSortableAttribute {
             field: "name".to_string(),
-            index: "index".to_string(),
+            index_name: Some("index".to_string()),
             valid_fields: list,
             hidden_fields: false,
         };
diff --git a/milli/src/index.rs b/milli/src/index.rs
index ad78f3946..b000cde27 100644
--- a/milli/src/index.rs
+++ b/milli/src/index.rs
@@ -1557,7 +1557,7 @@ pub(crate) mod tests {
             let mut options = EnvOpenOptions::new();
             options.map_size(size);
             let _tempdir = TempDir::new_in(".").unwrap();
-            let inner = Index::new("temp", options, _tempdir.path()).unwrap();
+            let inner = Index::new(Some("temp".to_string()), options, _tempdir.path()).unwrap();
             let indexer_config = IndexerConfig::default();
             let index_documents_config = IndexDocumentsConfig::default();
             Self { inner, indexer_config, index_documents_config, _tempdir }
diff --git a/milli/src/search/new/tests/integration.rs b/milli/src/search/new/tests/integration.rs
index 54cbd29fd..a60821b19 100644
--- a/milli/src/search/new/tests/integration.rs
+++ b/milli/src/search/new/tests/integration.rs
@@ -13,7 +13,7 @@ pub fn setup_search_index_with_criteria(criteria: &[Criterion]) -> Index {
     let path = tempfile::tempdir().unwrap();
     let mut options = EnvOpenOptions::new();
     options.map_size(10 * 1024 * 1024); // 10 MB
-    let index = Index::new("", options, &path).unwrap();
+    let index = Index::new(Some("".to_string()), options, &path).unwrap();
 
     let mut wtxn = index.write_txn().unwrap();
     let config = IndexerConfig::default();
diff --git a/milli/tests/search/facet_distribution.rs b/milli/tests/search/facet_distribution.rs
index 02da34283..55bc78fb2 100644
--- a/milli/tests/search/facet_distribution.rs
+++ b/milli/tests/search/facet_distribution.rs
@@ -13,7 +13,7 @@ fn test_facet_distribution_with_no_facet_values() {
     let path = tempfile::tempdir().unwrap();
     let mut options = EnvOpenOptions::new();
     options.map_size(10 * 1024 * 1024); // 10 MB
-    let index = Index::new("", options, &path).unwrap();
+    let index = Index::new(None, options, &path).unwrap();
 
     let mut wtxn = index.write_txn().unwrap();
     let config = IndexerConfig::default();
diff --git a/milli/tests/search/mod.rs b/milli/tests/search/mod.rs
index 71fbbea76..3ecbe6d67 100644
--- a/milli/tests/search/mod.rs
+++ b/milli/tests/search/mod.rs
@@ -31,7 +31,7 @@ pub fn setup_search_index_with_criteria(criteria: &[Criterion]) -> Index {
     let path = tempfile::tempdir().unwrap();
     let mut options = EnvOpenOptions::new();
     options.map_size(10 * 1024 * 1024); // 10 MB
-    let index = Index::new("", options, &path).unwrap();
+    let index = Index::new(None, options, &path).unwrap();
 
     let mut wtxn = index.write_txn().unwrap();
     let config = IndexerConfig::default();
diff --git a/milli/tests/search/query_criteria.rs b/milli/tests/search/query_criteria.rs
index 8b882b356..35c18426d 100644
--- a/milli/tests/search/query_criteria.rs
+++ b/milli/tests/search/query_criteria.rs
@@ -262,7 +262,7 @@ fn criteria_ascdesc() {
     let path = tempfile::tempdir().unwrap();
     let mut options = EnvOpenOptions::new();
     options.map_size(12 * 1024 * 1024); // 10 MB
-    let index = Index::new("", options, &path).unwrap();
+    let index = Index::new(None, options, &path).unwrap();
 
     let mut wtxn = index.write_txn().unwrap();
     let config = IndexerConfig::default();
diff --git a/milli/tests/search/typo_tolerance.rs b/milli/tests/search/typo_tolerance.rs
index 3e5d9dc9f..83024fb2f 100644
--- a/milli/tests/search/typo_tolerance.rs
+++ b/milli/tests/search/typo_tolerance.rs
@@ -104,7 +104,7 @@ fn test_typo_disabled_on_word() {
     let tmp = tempdir().unwrap();
     let mut options = EnvOpenOptions::new();
     options.map_size(4096 * 100);
-    let index = Index::new("", options, tmp.path()).unwrap();
+    let index = Index::new(None, options, tmp.path()).unwrap();
 
     let mut builder = milli::documents::DocumentsBatchBuilder::new(Vec::new());
     let doc1 = json!({