diff --git a/meilisearch-core/Cargo.toml b/meilisearch-core/Cargo.toml
index 1706b9af6..d9b88f89b 100644
--- a/meilisearch-core/Cargo.toml
+++ b/meilisearch-core/Cargo.toml
@@ -34,7 +34,7 @@ pest_derive = "2.0"
 regex = "1.3.6"
 sdset = "0.4.0"
 serde = { version = "1.0.105", features = ["derive"] }
-serde_json = "1.0.50"
+serde_json = { version = "1.0.50", features = ["preserve_order"] }
 siphasher = "0.3.2"
 slice-group-by = "0.2.6"
 unicase = "2.6.0"
diff --git a/meilisearch-core/src/serde/indexer.rs b/meilisearch-core/src/serde/indexer.rs
deleted file mode 100644
index c8b6abeaf..000000000
--- a/meilisearch-core/src/serde/indexer.rs
+++ /dev/null
@@ -1,362 +0,0 @@
-use meilisearch_schema::IndexedPos;
-use serde::ser;
-use serde::Serialize;
-
-use super::{ConvertToString, SerializerError};
-use crate::raw_indexer::RawIndexer;
-use crate::DocumentId;
-
-pub struct Indexer<'a> {
-    pub pos: IndexedPos,
-    pub indexer: &'a mut RawIndexer,
-    pub document_id: DocumentId,
-}
-
-impl<'a> ser::Serializer for Indexer<'a> {
-    type Ok = Option<usize>;
-    type Error = SerializerError;
-    type SerializeSeq = SeqIndexer<'a>;
-    type SerializeTuple = TupleIndexer<'a>;
-    type SerializeTupleStruct = ser::Impossible<Self::Ok, Self::Error>;
-    type SerializeTupleVariant = ser::Impossible<Self::Ok, Self::Error>;
-    type SerializeMap = MapIndexer<'a>;
-    type SerializeStruct = StructIndexer<'a>;
-    type SerializeStructVariant = ser::Impossible<Self::Ok, Self::Error>;
-
-    fn serialize_bool(self, _value: bool) -> Result<Self::Ok, Self::Error> {
-        Ok(None)
-    }
-
-    fn serialize_char(self, value: char) -> Result<Self::Ok, Self::Error> {
-        let text = value.serialize(ConvertToString)?;
-        self.serialize_str(&text)
-    }
-
-    fn serialize_i8(self, value: i8) -> Result<Self::Ok, Self::Error> {
-        let text = value.serialize(ConvertToString)?;
-        self.serialize_str(&text)
-    }
-
-    fn serialize_i16(self, value: i16) -> Result<Self::Ok, Self::Error> {
-        let text = value.serialize(ConvertToString)?;
-        self.serialize_str(&text)
-    }
-
-    fn serialize_i32(self, value: i32) -> Result<Self::Ok, Self::Error> {
-        let text = value.serialize(ConvertToString)?;
-        self.serialize_str(&text)
-    }
-
-    fn serialize_i64(self, value: i64) -> Result<Self::Ok, Self::Error> {
-        let text = value.serialize(ConvertToString)?;
-        self.serialize_str(&text)
-    }
-
-    fn serialize_u8(self, value: u8) -> Result<Self::Ok, Self::Error> {
-        let text = value.serialize(ConvertToString)?;
-        self.serialize_str(&text)
-    }
-
-    fn serialize_u16(self, value: u16) -> Result<Self::Ok, Self::Error> {
-        let text = value.serialize(ConvertToString)?;
-        self.serialize_str(&text)
-    }
-
-    fn serialize_u32(self, value: u32) -> Result<Self::Ok, Self::Error> {
-        let text = value.serialize(ConvertToString)?;
-        self.serialize_str(&text)
-    }
-
-    fn serialize_u64(self, value: u64) -> Result<Self::Ok, Self::Error> {
-        let text = value.serialize(ConvertToString)?;
-        self.serialize_str(&text)
-    }
-
-    fn serialize_f32(self, value: f32) -> Result<Self::Ok, Self::Error> {
-        let text = value.serialize(ConvertToString)?;
-        self.serialize_str(&text)
-    }
-
-    fn serialize_f64(self, value: f64) -> Result<Self::Ok, Self::Error> {
-        let text = value.serialize(ConvertToString)?;
-        self.serialize_str(&text)
-    }
-
-    fn serialize_str(self, text: &str) -> Result<Self::Ok, Self::Error> {
-        let number_of_words = self
-            .indexer
-            .index_text(self.document_id, self.pos, text);
-        Ok(Some(number_of_words))
-    }
-
-    fn serialize_bytes(self, _v: &[u8]) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnindexableType { type_name: "&[u8]" })
-    }
-
-    fn serialize_none(self) -> Result<Self::Ok, Self::Error> {
-        Ok(None)
-    }
-
-    fn serialize_some<T: ?Sized>(self, value: &T) -> Result<Self::Ok, Self::Error>
-    where
-        T: ser::Serialize,
-    {
-        let text = value.serialize(ConvertToString)?;
-        let number_of_words = self
-            .indexer
-            .index_text(self.document_id, self.pos, &text);
-        Ok(Some(number_of_words))
-    }
-
-    fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
-        Ok(None)
-    }
-
-    fn serialize_unit_struct(self, _name: &'static str) -> Result<Self::Ok, Self::Error> {
-        Ok(None)
-    }
-
-    fn serialize_unit_variant(
-        self,
-        _name: &'static str,
-        _variant_index: u32,
-        _variant: &'static str,
-    ) -> Result<Self::Ok, Self::Error> {
-        Ok(None)
-    }
-
-    fn serialize_newtype_struct<T: ?Sized>(
-        self,
-        _name: &'static str,
-        value: &T,
-    ) -> Result<Self::Ok, Self::Error>
-    where
-        T: ser::Serialize,
-    {
-        value.serialize(self)
-    }
-
-    fn serialize_newtype_variant<T: ?Sized>(
-        self,
-        _name: &'static str,
-        _variant_index: u32,
-        _variant: &'static str,
-        _value: &T,
-    ) -> Result<Self::Ok, Self::Error>
-    where
-        T: ser::Serialize,
-    {
-        Err(SerializerError::UnindexableType {
-            type_name: "newtype variant",
-        })
-    }
-
-    fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> {
-        let indexer = SeqIndexer {
-            pos: self.pos,
-            document_id: self.document_id,
-            indexer: self.indexer,
-            texts: Vec::new(),
-        };
-
-        Ok(indexer)
-    }
-
-    fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple, Self::Error> {
-        let indexer = TupleIndexer {
-            pos: self.pos,
-            document_id: self.document_id,
-            indexer: self.indexer,
-            texts: Vec::new(),
-        };
-
-        Ok(indexer)
-    }
-
-    fn serialize_tuple_struct(
-        self,
-        _name: &'static str,
-        _len: usize,
-    ) -> Result<Self::SerializeTupleStruct, Self::Error> {
-        Err(SerializerError::UnindexableType {
-            type_name: "tuple struct",
-        })
-    }
-
-    fn serialize_tuple_variant(
-        self,
-        _name: &'static str,
-        _variant_index: u32,
-        _variant: &'static str,
-        _len: usize,
-    ) -> Result<Self::SerializeTupleVariant, Self::Error> {
-        Err(SerializerError::UnindexableType {
-            type_name: "tuple variant",
-        })
-    }
-
-    fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
-        let indexer = MapIndexer {
-            pos: self.pos,
-            document_id: self.document_id,
-            indexer: self.indexer,
-            texts: Vec::new(),
-        };
-
-        Ok(indexer)
-    }
-
-    fn serialize_struct(
-        self,
-        _name: &'static str,
-        _len: usize,
-    ) -> Result<Self::SerializeStruct, Self::Error> {
-        let indexer = StructIndexer {
-            pos: self.pos,
-            document_id: self.document_id,
-            indexer: self.indexer,
-            texts: Vec::new(),
-        };
-
-        Ok(indexer)
-    }
-
-    fn serialize_struct_variant(
-        self,
-        _name: &'static str,
-        _variant_index: u32,
-        _variant: &'static str,
-        _len: usize,
-    ) -> Result<Self::SerializeStructVariant, Self::Error> {
-        Err(SerializerError::UnindexableType {
-            type_name: "struct variant",
-        })
-    }
-}
-
-pub struct SeqIndexer<'a> {
-    pos: IndexedPos,
-    document_id: DocumentId,
-    indexer: &'a mut RawIndexer,
-    texts: Vec<String>,
-}
-
-impl<'a> ser::SerializeSeq for SeqIndexer<'a> {
-    type Ok = Option<usize>;
-    type Error = SerializerError;
-
-    fn serialize_element<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error>
-    where
-        T: ser::Serialize,
-    {
-        let text = value.serialize(ConvertToString)?;
-        self.texts.push(text);
-        Ok(())
-    }
-
-    fn end(self) -> Result<Self::Ok, Self::Error> {
-        let texts = self.texts.iter().map(String::as_str);
-        self.indexer
-            .index_text_seq(self.document_id, self.pos, texts);
-        Ok(None)
-    }
-}
-
-pub struct MapIndexer<'a> {
-    pos: IndexedPos,
-    document_id: DocumentId,
-    indexer: &'a mut RawIndexer,
-    texts: Vec<String>,
-}
-
-impl<'a> ser::SerializeMap for MapIndexer<'a> {
-    type Ok = Option<usize>;
-    type Error = SerializerError;
-
-    fn serialize_key<T: ?Sized>(&mut self, key: &T) -> Result<(), Self::Error>
-    where
-        T: ser::Serialize,
-    {
-        let text = key.serialize(ConvertToString)?;
-        self.texts.push(text);
-        Ok(())
-    }
-
-    fn serialize_value<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error>
-    where
-        T: ser::Serialize,
-    {
-        let text = value.serialize(ConvertToString)?;
-        self.texts.push(text);
-        Ok(())
-    }
-
-    fn end(self) -> Result<Self::Ok, Self::Error> {
-        let texts = self.texts.iter().map(String::as_str);
-        self.indexer
-            .index_text_seq(self.document_id, self.pos, texts);
-        Ok(None)
-    }
-}
-
-pub struct StructIndexer<'a> {
-    pos: IndexedPos,
-    document_id: DocumentId,
-    indexer: &'a mut RawIndexer,
-    texts: Vec<String>,
-}
-
-impl<'a> ser::SerializeStruct for StructIndexer<'a> {
-    type Ok = Option<usize>;
-    type Error = SerializerError;
-
-    fn serialize_field<T: ?Sized>(
-        &mut self,
-        key: &'static str,
-        value: &T,
-    ) -> Result<(), Self::Error>
-    where
-        T: ser::Serialize,
-    {
-        let key_text = key.to_owned();
-        let value_text = value.serialize(ConvertToString)?;
-        self.texts.push(key_text);
-        self.texts.push(value_text);
-        Ok(())
-    }
-
-    fn end(self) -> Result<Self::Ok, Self::Error> {
-        let texts = self.texts.iter().map(String::as_str);
-        self.indexer
-            .index_text_seq(self.document_id, self.pos, texts);
-        Ok(None)
-    }
-}
-
-pub struct TupleIndexer<'a> {
-    pos: IndexedPos,
-    document_id: DocumentId,
-    indexer: &'a mut RawIndexer,
-    texts: Vec<String>,
-}
-
-impl<'a> ser::SerializeTuple for TupleIndexer<'a> {
-    type Ok = Option<usize>;
-    type Error = SerializerError;
-
-    fn serialize_element<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error>
-    where
-        T: Serialize,
-    {
-        let text = value.serialize(ConvertToString)?;
-        self.texts.push(text);
-        Ok(())
-    }
-
-    fn end(self) -> Result<Self::Ok, Self::Error> {
-        let texts = self.texts.iter().map(String::as_str);
-        self.indexer
-            .index_text_seq(self.document_id, self.pos, texts);
-        Ok(None)
-    }
-}
diff --git a/meilisearch-core/src/serde/mod.rs b/meilisearch-core/src/serde/mod.rs
index 9cb8e50bc..6a1e51a09 100644
--- a/meilisearch-core/src/serde/mod.rs
+++ b/meilisearch-core/src/serde/mod.rs
@@ -12,13 +12,11 @@ mod convert_to_number;
 mod convert_to_string;
 mod deserializer;
 mod extract_document_id;
-mod indexer;
 
 pub use self::convert_to_number::ConvertToNumber;
 pub use self::convert_to_string::ConvertToString;
 pub use self::deserializer::{Deserializer, DeserializerError};
 pub use self::extract_document_id::{compute_document_id, extract_document_id, value_to_string};
-pub use self::indexer::Indexer;
 
 use std::{error::Error, fmt};
 
diff --git a/meilisearch-core/src/update/documents_addition.rs b/meilisearch-core/src/update/documents_addition.rs
index c65cf6e81..b7e6395af 100644
--- a/meilisearch-core/src/update/documents_addition.rs
+++ b/meilisearch-core/src/update/documents_addition.rs
@@ -1,4 +1,6 @@
 use std::collections::HashMap;
+use std::fmt::Write as _;
+use std::fmt;
 
 use fst::{set::OpBuilder, SetBuilder};
 use indexmap::IndexMap;
@@ -6,12 +8,15 @@ use sdset::{duo::Union, SetOperation};
 use serde::{Deserialize, Serialize};
 use serde_json::Value;
 
+use meilisearch_types::DocumentId;
+use meilisearch_schema::IndexedPos;
+
 use crate::database::{MainT, UpdateT};
 use crate::database::{UpdateEvent, UpdateEventsEmitter};
 use crate::facets;
 use crate::raw_indexer::RawIndexer;
 use crate::serde::{extract_document_id, Deserializer};
-use crate::serde::{ConvertToNumber, Indexer};
+use crate::serde::ConvertToNumber;
 use crate::store;
 use crate::update::{apply_documents_deletion, compute_short_prefixes, next_update_id, Update};
 use crate::{Error, MResult, RankedMap};
@@ -106,6 +111,69 @@ pub fn push_documents_addition<D: serde::Serialize>(
     Ok(last_update_id)
 }
 
+// TODO move this helper functions elsewhere
+/// Returns the number of words indexed or `None` if the type
+fn index_value(
+    indexer: &mut RawIndexer,
+    document_id: DocumentId,
+    indexed_pos: IndexedPos,
+    value: &Value,
+) -> Option<usize>
+{
+    fn value_to_string(string: &mut String, value: &Value) {
+        match value {
+            Value::Null => (),
+            Value::Bool(boolean) => { let _ = write!(string, "{}", &boolean); },
+            Value::Number(number) => { let _ = write!(string, "{}", &number); },
+            Value::String(text) => string.push_str(&text),
+            Value::Array(array) => {
+                for value in array {
+                    value_to_string(string, value);
+                    let _ = string.write_str(". ");
+                }
+            },
+            Value::Object(object) => {
+                for (key, value) in object {
+                    string.push_str(key);
+                    let _ = string.write_str(". ");
+                    value_to_string(string, value);
+                    let _ = string.write_str(". ");
+                }
+            },
+        }
+    }
+
+    match value {
+        Value::Null => None,
+        Value::Bool(boolean) => {
+            let text = boolean.to_string();
+            let number_of_words = indexer.index_text(document_id, indexed_pos, &text);
+            Some(number_of_words)
+        },
+        Value::Number(number) => {
+            let text = number.to_string();
+            let number_of_words = indexer.index_text(document_id, indexed_pos, &text);
+            Some(number_of_words)
+        },
+        Value::String(string) => {
+            let number_of_words = indexer.index_text(document_id, indexed_pos, &string);
+            Some(number_of_words)
+        },
+        Value::Array(_) => {
+            let mut text = String::new();
+            value_to_string(&mut text, value);
+            let number_of_words = indexer.index_text(document_id, indexed_pos, &text);
+            Some(number_of_words)
+        },
+        Value::Object(_) => {
+            let mut text = String::new();
+            value_to_string(&mut text, value);
+            let number_of_words = indexer.index_text(document_id, indexed_pos, &text);
+            Some(number_of_words)
+        },
+    }
+}
+
 pub fn apply_addition<'a, 'b>(
     writer: &'a mut heed::RwTxn<'b, MainT>,
     index: &store::Index,
@@ -183,8 +251,8 @@ pub fn apply_addition<'a, 'b>(
             index.documents_fields.put_document_field(writer, document_id, field_id, &serialized)?;
 
             if let Some(indexed_pos) = schema.is_indexed(field_id) {
-                let indexer = Indexer { pos: *indexed_pos, indexer: &mut indexer, document_id };
-                if let Some(number_of_words) = value.serialize(indexer)? {
+                let number_of_words = index_value(&mut indexer, document_id, *indexed_pos, &value);
+                if let Some(number_of_words) = number_of_words {
                     index.documents_fields_counts.put_document_field_count(
                         writer,
                         document_id,
@@ -280,8 +348,8 @@ pub fn reindex_all_documents(writer: &mut heed::RwTxn<MainT>, index: &store::Ind
             index.documents_fields.put_document_field(writer, document_id, field_id, &serialized)?;
 
             if let Some(indexed_pos) = schema.is_indexed(field_id) {
-                let indexer = Indexer { pos: *indexed_pos, indexer: &mut indexer, document_id };
-                if let Some(number_of_words) = value.serialize(indexer)? {
+                let number_of_words = index_value(&mut indexer, document_id, *indexed_pos, &value);
+                if let Some(number_of_words) = number_of_words {
                     index.documents_fields_counts.put_document_field_count(
                         writer,
                         document_id,