diff --git a/meilidb-core/src/store/main.rs b/meilidb-core/src/store/main.rs
index 2712a0efa..cb5266187 100644
--- a/meilidb-core/src/store/main.rs
+++ b/meilidb-core/src/store/main.rs
@@ -3,8 +3,10 @@ use std::convert::TryInto;
 
 use meilidb_schema::Schema;
 use rkv::Value;
+use serde::de;
 use crate::{RankedMap, MResult};
 
+const CUSTOMS_KEY:             &str = "customs-key";
 const NUMBER_OF_DOCUMENTS_KEY: &str = "number-of-documents";
 const RANKED_MAP_KEY:          &str = "ranked-map";
 const SCHEMA_KEY:              &str = "schema";
@@ -63,7 +65,7 @@ impl Main {
     {
         match self.main.get(reader, SCHEMA_KEY)? {
             Some(Value::Blob(bytes)) => {
-                let schema = bincode::deserialize_from(bytes.as_ref())?;
+                let schema = bincode::deserialize_from(bytes)?;
                 Ok(Some(schema))
             },
             Some(value) => panic!("invalid type {:?}", value),
@@ -151,4 +153,17 @@ impl Main {
             None => Ok(0),
         }
     }
+
+    pub fn put_customs(&self, writer: &mut rkv::Writer, customs: &[u8]) -> MResult<()> {
+        self.main.put(writer, CUSTOMS_KEY, &Value::Blob(customs))?;
+        Ok(())
+    }
+
+    pub fn customs<'t>(&self, reader: &'t impl rkv::Readable) -> MResult<Option<&'t [u8]>> {
+        match self.main.get(reader, CUSTOMS_KEY)? {
+            Some(Value::Blob(bytes)) => Ok(Some(bytes)),
+            Some(value) => panic!("invalid type {:?}", value),
+            None => Ok(None),
+        }
+    }
 }
diff --git a/meilidb-core/src/store/mod.rs b/meilidb-core/src/store/mod.rs
index 228aa74bd..957ee8520 100644
--- a/meilidb-core/src/store/mod.rs
+++ b/meilidb-core/src/store/mod.rs
@@ -16,7 +16,7 @@ pub use self::updates_results::UpdatesResults;
 
 use std::collections::HashSet;
 use meilidb_schema::{Schema, SchemaAttr};
-use serde::de;
+use serde::{ser, de};
 use crate::criterion::Criteria;
 use crate::serde::Deserializer;
 use crate::{update, query_builder::QueryBuilder, DocumentId, MResult, Error};
@@ -109,10 +109,14 @@ impl Index {
         }
     }
 
-    pub fn schema_update(&self, writer: &mut rkv::Writer, schema: Schema) -> MResult<()> {
+    pub fn schema_update(&self, writer: &mut rkv::Writer, schema: Schema) -> MResult<u64> {
         let _ = self.updates_notifier.send(());
-        update::push_schema_update(writer, self.updates, self.updates_results, schema)?;
-        Ok(())
+        update::push_schema_update(writer, self.updates, self.updates_results, schema)
+    }
+
+    pub fn customs_update(&self, writer: &mut rkv::Writer, customs: Vec<u8>) -> MResult<u64> {
+        let _ = self.updates_notifier.send(());
+        update::push_customs_update(writer, self.updates, self.updates_results, customs)
     }
 
     pub fn documents_addition<D>(&self) -> update::DocumentsAddition<D> {
diff --git a/meilidb-core/src/update/customs_update.rs b/meilidb-core/src/update/customs_update.rs
new file mode 100644
index 000000000..fa65d7c67
--- /dev/null
+++ b/meilidb-core/src/update/customs_update.rs
@@ -0,0 +1,26 @@
+use crate::{store, error::UnsupportedOperation, MResult};
+use crate::update::{Update, next_update_id};
+
+pub fn apply_customs_update(
+    writer: &mut rkv::Writer,
+    main_store: store::Main,
+    customs: &[u8],
+) -> MResult<()>
+{
+    main_store.put_customs(writer, customs)
+}
+
+pub fn push_customs_update(
+    writer: &mut rkv::Writer,
+    updates_store: store::Updates,
+    updates_results_store: store::UpdatesResults,
+    customs: Vec<u8>,
+) -> MResult<u64>
+{
+    let last_update_id = next_update_id(writer, updates_store, updates_results_store)?;
+
+    let update = Update::Customs(customs);
+    updates_store.put_update(writer, last_update_id, &update)?;
+
+    Ok(last_update_id)
+}
diff --git a/meilidb-core/src/update/mod.rs b/meilidb-core/src/update/mod.rs
index 0025e2e28..794c2f8ec 100644
--- a/meilidb-core/src/update/mod.rs
+++ b/meilidb-core/src/update/mod.rs
@@ -1,9 +1,11 @@
+mod customs_update;
 mod documents_addition;
 mod documents_deletion;
 mod schema_update;
 mod synonyms_addition;
 mod synonyms_deletion;
 
+pub use self::customs_update::{apply_customs_update, push_customs_update};
 pub use self::documents_addition::{DocumentsAddition, apply_documents_addition};
 pub use self::documents_deletion::{DocumentsDeletion, apply_documents_deletion};
 pub use self::schema_update::{apply_schema_update, push_schema_update};
@@ -22,7 +24,8 @@ use meilidb_schema::Schema;
 
 #[derive(Debug, Serialize, Deserialize)]
 pub enum Update {
-    SchemaUpdate(Schema),
+    Schema(Schema),
+    Customs(Vec<u8>),
     DocumentsAddition(Vec<rmpv::Value>),
     DocumentsDeletion(Vec<DocumentId>),
     SynonymsAddition(BTreeMap<String, Vec<String>>),
@@ -31,7 +34,8 @@ pub enum Update {
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub enum UpdateType {
-    SchemaUpdate { schema: Schema },
+    Schema { schema: Schema },
+    Customs,
     DocumentsAddition { number: usize },
     DocumentsDeletion { number: usize },
     SynonymsAddition { number: usize },
@@ -104,14 +108,22 @@ pub fn update_task(writer: &mut rkv::Writer, index: store::Index) -> MResult<Opt
     debug!("Processing update number {}", update_id);
 
     let (update_type, result, duration) = match update {
-        Update::SchemaUpdate(schema) => {
+        Update::Schema(schema) => {
             let start = Instant::now();
 
-            let update_type = UpdateType::SchemaUpdate { schema: schema.clone() };
+            let update_type = UpdateType::Schema { schema: schema.clone() };
             let result = apply_schema_update(writer, index.main, &schema);
 
             (update_type, result, start.elapsed())
         },
+        Update::Customs(customs) => {
+            let start = Instant::now();
+
+            let update_type = UpdateType::Customs;
+            let result = apply_customs_update(writer, index.main, &customs);
+
+            (update_type, result, start.elapsed())
+        }
         Update::DocumentsAddition(documents) => {
             let start = Instant::now();
 
diff --git a/meilidb-core/src/update/schema_update.rs b/meilidb-core/src/update/schema_update.rs
index 6c258c388..6e11c997d 100644
--- a/meilidb-core/src/update/schema_update.rs
+++ b/meilidb-core/src/update/schema_update.rs
@@ -24,7 +24,7 @@ pub fn push_schema_update(
 {
     let last_update_id = next_update_id(writer, updates_store, updates_results_store)?;
 
-    let update = Update::SchemaUpdate(schema);
+    let update = Update::Schema(schema);
     updates_store.put_update(writer, last_update_id, &update)?;
 
     Ok(last_update_id)