diff --git a/src/automaton/mod.rs b/src/automaton/mod.rs
index 8c5c68d98..79422c1ff 100644
--- a/src/automaton/mod.rs
+++ b/src/automaton/mod.rs
@@ -22,7 +22,7 @@ pub struct AutomatonProducer {
 
 impl AutomatonProducer {
     pub fn new(
-        reader: &rkv::Reader,
+        reader: &impl rkv::Readable,
         query: &str,
         synonyms_store: store::Synonyms,
     ) -> (AutomatonProducer, QueryEnhancer)
@@ -99,7 +99,7 @@ pub fn normalize_str(string: &str) -> String {
 }
 
 fn generate_automatons(
-    reader: &rkv::Reader,
+    reader: &impl rkv::Readable,
     query: &str,
     synonym_store: store::Synonyms,
 ) -> Result<(Vec<Vec<Automaton>>, QueryEnhancer), rkv::StoreError>
diff --git a/src/lib.rs b/src/lib.rs
index 99f85dcb1..f917f652b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -21,8 +21,6 @@ use self::ranked_map::RankedMap;
 use zerocopy::{AsBytes, FromBytes};
 use ::serde::{Serialize, Deserialize};
 
-pub type BEI64 = zerocopy::I64<byteorder::BigEndian>;
-
 /// Represent an internally generated document unique identifier.
 ///
 /// It is used to inform the database the document you want to deserialize.
diff --git a/src/query_builder.rs b/src/query_builder.rs
index d91ec94f5..b488d17b0 100644
--- a/src/query_builder.rs
+++ b/src/query_builder.rs
@@ -119,7 +119,7 @@ fn multiword_rewrite_matches(
 }
 
 fn fetch_raw_documents(
-    reader: &rkv::Reader,
+    reader: &impl rkv::Readable,
     automatons: &[Automaton],
     query_enhancer: &QueryEnhancer,
     searchables: Option<&ReorderedAttrs>,
@@ -203,7 +203,7 @@ impl<'a> QueryBuilder<'a> {
 
     pub fn query(
         self,
-        reader: &rkv::Reader,
+        reader: &impl rkv::Readable,
         query: &str,
         range: Range<usize>,
     ) -> MResult<Vec<Document>>
diff --git a/src/store/documents_fields.rs b/src/store/documents_fields.rs
index 6a80f7e0f..592d171e7 100644
--- a/src/store/documents_fields.rs
+++ b/src/store/documents_fields.rs
@@ -63,9 +63,9 @@ impl DocumentsFields {
         Ok(count)
     }
 
-    pub fn document_field<'a, T: rkv::Readable>(
+    pub fn document_field<'a>(
         &self,
-        reader: &'a T,
+        reader: &'a impl rkv::Readable,
         document_id: DocumentId,
         attribute: SchemaAttr,
     ) -> Result<Option<&'a [u8]>, rkv::StoreError>
diff --git a/src/store/main.rs b/src/store/main.rs
index a2cace7fe..8011e0e7d 100644
--- a/src/store/main.rs
+++ b/src/store/main.rs
@@ -26,9 +26,9 @@ impl Main {
         self.main.put(writer, WORDS_KEY, &blob)
     }
 
-    pub fn words_fst<T: rkv::Readable>(
+    pub fn words_fst(
         &self,
-        reader: &T,
+        reader: &impl rkv::Readable,
     ) -> MResult<Option<fst::Set>>
     {
         match self.main.get(reader, WORDS_KEY)? {
@@ -56,9 +56,9 @@ impl Main {
         Ok(())
     }
 
-    pub fn ranked_map<T: rkv::Readable>(
+    pub fn ranked_map(
         &self,
-        reader: &T,
+        reader: &impl rkv::Readable,
     ) -> MResult<Option<RankedMap>>
     {
         match self.main.get(reader, RANKED_MAP_KEY)? {
@@ -82,9 +82,9 @@ impl Main {
         Ok(new)
     }
 
-    pub fn number_of_documents<T: rkv::Readable>(
+    pub fn number_of_documents(
         &self,
-        reader: &T,
+        reader: &impl rkv::Readable,
     ) -> Result<u64, rkv::StoreError>
     {
         match self.main.get(reader, NUMBER_OF_DOCUMENTS_KEY)? {
diff --git a/src/store/postings_lists.rs b/src/store/postings_lists.rs
index 3af7077c0..b66ec3fb3 100644
--- a/src/store/postings_lists.rs
+++ b/src/store/postings_lists.rs
@@ -31,9 +31,9 @@ impl PostingsLists {
         self.postings_lists.delete(writer, word)
     }
 
-    pub fn postings_list<'a, T: rkv::Readable>(
+    pub fn postings_list<'a>(
         &self,
-        reader: &'a T,
+        reader: &'a impl rkv::Readable,
         word: &[u8],
     ) -> Result<Option<Cow<'a, sdset::Set<DocIndex>>>, rkv::StoreError>
     {
diff --git a/src/store/synonyms.rs b/src/store/synonyms.rs
index d605de35a..e254420d8 100644
--- a/src/store/synonyms.rs
+++ b/src/store/synonyms.rs
@@ -4,17 +4,17 @@ pub struct Synonyms {
 }
 
 impl Synonyms {
-    pub fn synonyms_fst<T: rkv::Readable>(
+    pub fn synonyms_fst(
         &self,
-        reader: &T,
+        reader: &impl rkv::Readable,
     ) -> Result<fst::Set, rkv::StoreError>
     {
         Ok(fst::Set::default())
     }
 
-    pub fn alternatives_to<T: rkv::Readable>(
+    pub fn alternatives_to(
         &self,
-        reader: &T,
+        reader: &impl rkv::Readable,
         word: &[u8],
     ) -> Result<Option<fst::Set>, rkv::StoreError>
     {
diff --git a/src/store/updates.rs b/src/store/updates.rs
index 21264cc5e..e6f6f0786 100644
--- a/src/store/updates.rs
+++ b/src/store/updates.rs
@@ -10,9 +10,9 @@ pub struct Updates {
 impl Updates {
     // TODO we should use the MDB_LAST op but
     //      it is not exposed by the rkv library
-    fn last_update_id<'a, T: rkv::Readable>(
+    fn last_update_id<'a>(
         &self,
-        reader: &'a T,
+        reader: &'a impl rkv::Readable,
     ) -> Result<Option<(u64, Option<Value<'a>>)>, rkv::StoreError>
     {
         let mut last = None;
@@ -33,9 +33,9 @@ impl Updates {
         Ok(Some((number, last_data)))
     }
 
-    pub fn contains<T: rkv::Readable>(
+    pub fn contains(
         &self,
-        reader: &T,
+        reader: &impl rkv::Readable,
         update_id: u64,
     ) -> Result<bool, rkv::StoreError>
     {
diff --git a/src/store/updates_results.rs b/src/store/updates_results.rs
index 527d7d376..8fe0ccb9f 100644
--- a/src/store/updates_results.rs
+++ b/src/store/updates_results.rs
@@ -21,9 +21,9 @@ impl UpdatesResults {
         Ok(())
     }
 
-    pub fn update_result<T: rkv::Readable>(
+    pub fn update_result(
         &self,
-        reader: &T,
+        reader: &impl rkv::Readable,
         update_id: u64,
     ) -> MResult<Option<UpdateResult>>
     {