diff --git a/src/database/database_view.rs b/src/database/database_view.rs
index 91f097660..20f3340e5 100644
--- a/src/database/database_view.rs
+++ b/src/database/database_view.rs
@@ -9,24 +9,9 @@ use crate::database::deserializer::{Deserializer, DeserializerError};
 use crate::database::{DATA_INDEX, DATA_SCHEMA};
 use crate::blob::positive::PositiveBlob;
 use crate::index::schema::Schema;
-use crate::database::{DocumentKey, DocumentKeyAttr};
+use crate::database::{retrieve_data_schema, DocumentKey, DocumentKeyAttr};
 use crate::DocumentId;
 
-// FIXME Do not panic!
-fn retrieve_data_schema(snapshot: &Snapshot<&DB>) -> Result<Schema, Box<Error>> {
-    match snapshot.get(DATA_SCHEMA)? {
-        Some(vector) => Ok(Schema::read_from(&*vector)?),
-        None => panic!("BUG: no schema found in the database"),
-    }
-}
-
-fn retrieve_data_index(snapshot: &Snapshot<&DB>) -> Result<PositiveBlob, Box<Error>> {
-    match snapshot.get(DATA_INDEX)? {
-        Some(vector) => Ok(bincode::deserialize(&*vector)?),
-        None => Ok(PositiveBlob::default()),
-    }
-}
-
 pub struct DatabaseView<'a> {
     snapshot: Snapshot<&'a DB>,
     schema: Schema,
diff --git a/src/database/mod.rs b/src/database/mod.rs
index 246071a1a..a990fffae 100644
--- a/src/database/mod.rs
+++ b/src/database/mod.rs
@@ -1,15 +1,17 @@
 use std::error::Error;
 use std::path::Path;
+use std::ops::Deref;
 use std::fmt;
 
 use rocksdb::rocksdb_options::{DBOptions, IngestExternalFileOptions, ColumnFamilyOptions};
 use rocksdb::{DB, DBVector, MergeOperands, SeekKey};
-use rocksdb::rocksdb::Writable;
+use rocksdb::rocksdb::{Writable, Snapshot};
 
-pub use crate::database::database_view::DatabaseView;
 pub use crate::database::document_key::{DocumentKey, DocumentKeyAttr};
+pub use crate::database::database_view::DatabaseView;
 use crate::index::update::Update;
 use crate::index::schema::Schema;
+use crate::blob::positive::PositiveBlob;
 use crate::blob::{self, Blob};
 
 mod document_key;
@@ -19,6 +21,24 @@ mod deserializer;
 const DATA_INDEX:  &[u8] = b"data-index";
 const DATA_SCHEMA: &[u8] = b"data-schema";
 
+pub fn retrieve_data_schema<D>(snapshot: &Snapshot<D>) -> Result<Schema, Box<Error>>
+where D: Deref<Target=DB>
+{
+    match snapshot.get(DATA_SCHEMA)? {
+        Some(vector) => Ok(Schema::read_from(&*vector)?),
+        None => Err(String::from("BUG: no schema found in the database").into()),
+    }
+}
+
+pub fn retrieve_data_index<D>(snapshot: &Snapshot<D>) -> Result<PositiveBlob, Box<Error>>
+where D: Deref<Target=DB>
+{
+    match snapshot.get(DATA_INDEX)? {
+        Some(vector) => Ok(bincode::deserialize(&*vector)?),
+        None => Ok(PositiveBlob::default()),
+    }
+}
+
 pub struct Database(DB);
 
 impl Database {
@@ -162,14 +182,14 @@ mod tests {
         struct SimpleDoc {
             title: String,
             description: String,
+            timestamp: u64,
         }
 
-        let title;
-        let description;
         let schema = {
             let mut builder = SchemaBuilder::new();
-            title = builder.new_attribute("title", STORED | INDEXED);
-            description = builder.new_attribute("description", STORED | INDEXED);
+            builder.new_attribute("title", STORED | INDEXED);
+            builder.new_attribute("description", STORED | INDEXED);
+            builder.new_attribute("timestamp", STORED);
             builder.build()
         };
 
@@ -181,21 +201,17 @@ mod tests {
         let doc0 = SimpleDoc {
             title: String::from("I am a title"),
             description: String::from("I am a description"),
+            timestamp: 1234567,
         };
         let doc1 = SimpleDoc {
             title: String::from("I am the second title"),
             description: String::from("I am the second description"),
+            timestamp: 7654321,
         };
 
         let mut update = {
             let mut builder = PositiveUpdateBuilder::new(update_path, schema, tokenizer_builder);
 
-            // builder.update_field(0, title, doc0.title.clone());
-            // builder.update_field(0, description, doc0.description.clone());
-
-            // builder.update_field(1, title, doc1.title.clone());
-            // builder.update_field(1, description, doc1.description.clone());
-
             builder.update(0, &doc0).unwrap();
             builder.update(1, &doc1).unwrap();
 
@@ -206,19 +222,9 @@ mod tests {
         database.ingest_update_file(update)?;
         let view = database.view()?;
 
-        println!("{:?}", view);
-
-        #[derive(Deserialize, Debug, Clone, PartialEq, Eq)]
-        struct DeSimpleDoc {
-            title: char,
-        }
-
         let de_doc0: SimpleDoc = view.retrieve_document(0)?;
         let de_doc1: SimpleDoc = view.retrieve_document(1)?;
 
-        println!("{:?}", de_doc0);
-        println!("{:?}", de_doc1);
-
         assert_eq!(doc0, de_doc0);
         assert_eq!(doc1, de_doc1);
 
diff --git a/src/index/update/positive/update.rs b/src/index/update/positive/update.rs
index c5154d270..da25ffb41 100644
--- a/src/index/update/positive/update.rs
+++ b/src/index/update/positive/update.rs
@@ -25,6 +25,7 @@ pub struct PositiveUpdateBuilder<B> {
     path: PathBuf,
     schema: Schema,
     tokenizer_builder: B,
+    builder: UnorderedPositiveBlobBuilder<Vec<u8>, Vec<u8>>,
     new_states: BTreeMap<(DocumentId, SchemaAttr), NewState>,
 }
 
@@ -34,14 +35,19 @@ impl<B> PositiveUpdateBuilder<B> {
             path: path.into(),
             schema: schema,
             tokenizer_builder: tokenizer_builder,
+            builder: UnorderedPositiveBlobBuilder::memory(),
             new_states: BTreeMap::new(),
         }
     }
 
-    pub fn update<T: Serialize>(&mut self, id: DocumentId, document: &T) -> Result<(), Box<Error>> {
+    pub fn update<T: Serialize>(&mut self, id: DocumentId, document: &T) -> Result<(), Box<Error>>
+    where B: TokenizerBuilder
+    {
         let serializer = Serializer {
             schema: &self.schema,
             document_id: id,
+            tokenizer_builder: &self.tokenizer_builder,
+            builder: &mut self.builder,
             new_states: &mut self.new_states
         };
 
@@ -90,9 +96,11 @@ impl fmt::Display for SerializerError {
 
 impl Error for SerializerError {}
 
-struct Serializer<'a> {
+struct Serializer<'a, B> {
     schema: &'a Schema,
+    tokenizer_builder: &'a B,
     document_id: DocumentId,
+    builder: &'a mut UnorderedPositiveBlobBuilder<Vec<u8>, Vec<u8>>,
     new_states: &'a mut BTreeMap<(DocumentId, SchemaAttr), NewState>,
 }
 
@@ -106,7 +114,9 @@ macro_rules! forward_to_unserializable_type {
     }
 }
 
-impl<'a> ser::Serializer for Serializer<'a> {
+impl<'a, B> ser::Serializer for Serializer<'a, B>
+where B: TokenizerBuilder
+{
     type Ok = ();
     type Error = SerializerError;
     type SerializeSeq = ser::Impossible<Self::Ok, Self::Error>;
@@ -114,7 +124,7 @@ impl<'a> ser::Serializer for Serializer<'a> {
     type SerializeTupleStruct = ser::Impossible<Self::Ok, Self::Error>;
     type SerializeTupleVariant = ser::Impossible<Self::Ok, Self::Error>;
     type SerializeMap = ser::Impossible<Self::Ok, Self::Error>;
-    type SerializeStruct = StructSerializer<'a>;
+    type SerializeStruct = StructSerializer<'a, B>;
     type SerializeStructVariant = ser::Impossible<Self::Ok, Self::Error>;
 
     forward_to_unserializable_type! {
@@ -238,7 +248,9 @@ impl<'a> ser::Serializer for Serializer<'a> {
     {
         Ok(StructSerializer {
             schema: self.schema,
+            tokenizer_builder: self.tokenizer_builder,
             document_id: self.document_id,
+            builder: self.builder,
             new_states: self.new_states,
         })
     }
@@ -255,33 +267,17 @@ impl<'a> ser::Serializer for Serializer<'a> {
     }
 }
 
-fn serialize_field(
-    schema: &Schema,
-    document_id: DocumentId,
-    new_states: &mut BTreeMap<(DocumentId, SchemaAttr), NewState>,
-    name: &str,
-    value: Vec<u8>,
-) -> Result<(), SerializerError>
-{
-    match schema.attribute(name) {
-        Some(attr) => {
-            let props = schema.props(attr);
-            if props.is_stored() {
-                new_states.insert((document_id, attr), NewState::Updated { value });
-            }
-            Ok(())
-        },
-        None => Err(SerializerError::SchemaDontMatch { attribute: name.to_owned() }),
-    }
-}
-
-struct StructSerializer<'a> {
+struct StructSerializer<'a, B> {
     schema: &'a Schema,
+    tokenizer_builder: &'a B,
     document_id: DocumentId,
+    builder: &'a mut UnorderedPositiveBlobBuilder<Vec<u8>, Vec<u8>>,
     new_states: &'a mut BTreeMap<(DocumentId, SchemaAttr), NewState>,
 }
 
-impl<'a> ser::SerializeStruct for StructSerializer<'a> {
+impl<'a, B> ser::SerializeStruct for StructSerializer<'a, B>
+where B: TokenizerBuilder
+{
     type Ok = ();
     type Error = SerializerError;
 
@@ -292,11 +288,26 @@ impl<'a> ser::SerializeStruct for StructSerializer<'a> {
     ) -> Result<(), Self::Error>
     where T: Serialize,
     {
-        let value = match bincode::serialize(value) {
-            Ok(value) => value,
-            Err(e) => return Err(SerializerError::UnserializableType { name: "???" }),
-        };
-        serialize_field(self.schema, self.document_id, self.new_states, key, value)
+        match self.schema.attribute(key) {
+            Some(attr) => {
+                let props = self.schema.props(attr);
+                if props.is_stored() {
+                    let value = bincode::serialize(value).unwrap();
+                    self.new_states.insert((self.document_id, attr), NewState::Updated { value });
+                }
+                if props.is_indexed() {
+                    let serializer = IndexerSerializer {
+                        builder: self.builder,
+                        tokenizer_builder: self.tokenizer_builder,
+                        document_id: self.document_id,
+                        attribute: attr,
+                    };
+                    value.serialize(serializer)?;
+                }
+                Ok(())
+            },
+            None => Err(SerializerError::SchemaDontMatch { attribute: key.to_owned() }),
+        }
     }
 
     fn end(self) -> Result<Self::Ok, Self::Error> {
@@ -304,52 +315,181 @@ impl<'a> ser::SerializeStruct for StructSerializer<'a> {
     }
 }
 
-impl<B> PositiveUpdateBuilder<B>
+struct IndexerSerializer<'a, B> {
+    tokenizer_builder: &'a B,
+    builder: &'a mut UnorderedPositiveBlobBuilder<Vec<u8>, Vec<u8>>,
+    document_id: DocumentId,
+    attribute: SchemaAttr,
+}
+
+impl<'a, B> ser::Serializer for IndexerSerializer<'a, B>
 where B: TokenizerBuilder
 {
+    type Ok = ();
+    type Error = SerializerError;
+    type SerializeSeq = ser::Impossible<Self::Ok, Self::Error>;
+    type SerializeTuple = ser::Impossible<Self::Ok, Self::Error>;
+    type SerializeTupleStruct = ser::Impossible<Self::Ok, Self::Error>;
+    type SerializeTupleVariant = ser::Impossible<Self::Ok, Self::Error>;
+    type SerializeMap = ser::Impossible<Self::Ok, Self::Error>;
+    type SerializeStruct = ser::Impossible<Self::Ok, Self::Error>;
+    type SerializeStructVariant = ser::Impossible<Self::Ok, Self::Error>;
+
+    forward_to_unserializable_type! {
+        bool => serialize_bool,
+        char => serialize_char,
+
+        i8  => serialize_i8,
+        i16 => serialize_i16,
+        i32 => serialize_i32,
+        i64 => serialize_i64,
+
+        u8  => serialize_u8,
+        u16 => serialize_u16,
+        u32 => serialize_u32,
+        u64 => serialize_u64,
+
+        f32 => serialize_f32,
+        f64 => serialize_f64,
+    }
+
+    fn serialize_str(self, v: &str) -> Result<Self::Ok, Self::Error> {
+        for (index, word) in self.tokenizer_builder.build(v) {
+            let doc_index = DocIndex {
+                document_id: self.document_id,
+                attribute: self.attribute.as_u32() as u8,
+                attribute_index: index as u32,
+            };
+
+            // insert the exact representation
+            let word_lower = word.to_lowercase();
+
+            // and the unidecoded lowercased version
+            let word_unidecoded = unidecode::unidecode(word).to_lowercase();
+            if word_lower != word_unidecoded {
+                self.builder.insert(word_unidecoded, doc_index);
+            }
+
+            self.builder.insert(word_lower, doc_index);
+        }
+        Ok(())
+    }
+
+    fn serialize_bytes(self, v: &[u8]) -> Result<Self::Ok, Self::Error> {
+        Err(SerializerError::UnserializableType { name: "&[u8]" })
+    }
+
+    fn serialize_none(self) -> Result<Self::Ok, Self::Error> {
+        Err(SerializerError::UnserializableType { name: "Option" })
+    }
+
+    fn serialize_some<T: ?Sized>(self, _value: &T) -> Result<Self::Ok, Self::Error>
+    where T: Serialize,
+    {
+        Err(SerializerError::UnserializableType { name: "Option" })
+    }
+
+    fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
+        Err(SerializerError::UnserializableType { name: "()" })
+    }
+
+    fn serialize_unit_struct(self, _name: &'static str) -> Result<Self::Ok, Self::Error> {
+        Err(SerializerError::UnserializableType { name: "unit struct" })
+    }
+
+    fn serialize_unit_variant(
+        self,
+        _name: &'static str,
+        _variant_index: u32,
+        _variant: &'static str
+    ) -> Result<Self::Ok, Self::Error>
+    {
+        Err(SerializerError::UnserializableType { name: "unit variant" })
+    }
+
+    fn serialize_newtype_struct<T: ?Sized>(
+        self,
+        _name: &'static str,
+        value: &T
+    ) -> Result<Self::Ok, Self::Error>
+    where T: 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: Serialize,
+    {
+        Err(SerializerError::UnserializableType { name: "newtype variant" })
+    }
+
+    fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> {
+        Err(SerializerError::UnserializableType { name: "seq" })
+    }
+
+    fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple, Self::Error> {
+        Err(SerializerError::UnserializableType { name: "tuple" })
+    }
+
+    fn serialize_tuple_struct(
+        self,
+        _name: &'static str,
+        _len: usize
+    ) -> Result<Self::SerializeTupleStruct, Self::Error>
+    {
+        Err(SerializerError::UnserializableType { 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::UnserializableType { name: "tuple variant" })
+    }
+
+    fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
+        Err(SerializerError::UnserializableType { name: "map" })
+    }
+
+    fn serialize_struct(
+        self,
+        _name: &'static str,
+        _len: usize
+    ) -> Result<Self::SerializeStruct, Self::Error>
+    {
+        Err(SerializerError::UnserializableType { name: "struct" })
+    }
+
+    fn serialize_struct_variant(
+        self,
+        _name: &'static str,
+        _variant_index: u32,
+        _variant: &'static str,
+        _len: usize
+    ) -> Result<Self::SerializeStructVariant, Self::Error>
+    {
+        Err(SerializerError::UnserializableType { name: "struct variant" })
+    }
+}
+
+impl<B> PositiveUpdateBuilder<B> {
     pub fn build(self) -> Result<Update, Box<Error>> {
         let env_options = rocksdb_options::EnvOptions::new();
         let column_family_options = rocksdb_options::ColumnFamilyOptions::new();
         let mut file_writer = rocksdb::SstFileWriter::new(env_options, column_family_options);
         file_writer.open(&self.path.to_string_lossy())?;
 
-        let mut builder = UnorderedPositiveBlobBuilder::memory();
-        for ((document_id, attr), state) in &self.new_states {
-            let props = self.schema.props(*attr);
-            let value = match state {
-                NewState::Updated { value } if props.is_indexed() => value,
-                _ => continue,
-            };
-
-            let value: String = match bincode::deserialize(&value) {
-                Ok(value) => value,
-                Err(e) => {
-                    eprintln!("{}", e);
-                    continue
-                },
-            };
-
-            for (index, word) in self.tokenizer_builder.build(&value) {
-                let doc_index = DocIndex {
-                    document_id: *document_id,
-                    attribute: attr.as_u32() as u8,
-                    attribute_index: index as u32,
-                };
-
-                // insert the exact representation
-                let word_lower = word.to_lowercase();
-
-                // and the unidecoded lowercased version
-                let word_unidecoded = unidecode::unidecode(word).to_lowercase();
-                if word_lower != word_unidecoded {
-                    builder.insert(word_unidecoded, doc_index);
-                }
-
-                builder.insert(word_lower, doc_index);
-            }
-        }
-
-        let (blob_fst_map, blob_doc_idx) = builder.into_inner()?;
+        let (blob_fst_map, blob_doc_idx) = self.builder.into_inner()?;
         let positive_blob = PositiveBlob::from_bytes(blob_fst_map, blob_doc_idx)?;
         let blob = Blob::Positive(positive_blob);
 
diff --git a/src/lib.rs b/src/lib.rs
index ecb48b9b9..f83e59c37 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -2,7 +2,6 @@ pub mod automaton;
 pub mod blob;
 pub mod database;
 pub mod data;
-pub mod retrieve;
 pub mod index;
 pub mod rank;
 pub mod tokenizer;
diff --git a/src/rank/ranked_stream.rs b/src/rank/ranked_stream.rs
index df32f9f32..6dba99c9a 100644
--- a/src/rank/ranked_stream.rs
+++ b/src/rank/ranked_stream.rs
@@ -11,9 +11,9 @@ use fst::Streamer;
 use crate::automaton::{self, DfaExt, AutomatonExt};
 use crate::rank::criterion::{self, Criterion};
 use crate::rank::distinct_map::DistinctMap;
+use crate::database::retrieve_data_index;
 use crate::blob::PositiveBlob;
 use crate::{Match, DocumentId};
-use crate::retrieve::Retrieve;
 use crate::rank::Document;
 
 fn clamp_range<T: Copy + Ord>(range: Range<T>, big: Range<T>) -> Range<T> {
@@ -48,7 +48,7 @@ impl<T, C> QueryBuilder<T, C>
 where T: Deref<Target=DB>,
 {
     pub fn with_criteria(snapshot: Snapshot<T>, criteria: Vec<C>) -> Result<Self, Box<Error>> {
-        let blob = snapshot.data_index()?;
+        let blob = retrieve_data_index(&snapshot)?;
         Ok(QueryBuilder { snapshot, blob, criteria })
     }
 
diff --git a/src/retrieve.rs b/src/retrieve.rs
deleted file mode 100644
index d9ba3f4a0..000000000
--- a/src/retrieve.rs
+++ /dev/null
@@ -1,60 +0,0 @@
-use std::error::Error;
-use std::ops::Deref;
-
-use ::rocksdb::rocksdb::{DB, Snapshot, DBVector};
-
-use crate::index::schema::{Schema, SchemaAttr};
-use crate::blob::PositiveBlob;
-use crate::DocumentId;
-
-pub struct DocDatabase<'a, R: ?Sized> {
-    retrieve: &'a R,
-    schema: Schema,
-}
-
-impl<'a, R> DocDatabase<'a, R> {
-    pub fn get_document<D>(&self, id: DocumentId) -> Result<Option<D>, Box<Error>> {
-        // if ids.is_empty() { return Ok(Vec::new()) }
-        unimplemented!()
-    }
-
-    pub fn get_document_attribute(&self, id: DocumentId, attr: SchemaAttr) -> Result<DBVector, Box<Error>> {
-        unimplemented!()
-    }
-}
-
-pub trait Retrieve {
-    fn schema(&self) -> Result<Option<Schema>, Box<Error>>;
-    fn data_index(&self) -> Result<PositiveBlob, Box<Error>>;
-    fn doc_database(&self) -> Result<DocDatabase<Self>, Box<Error>>;
-}
-
-impl<T> Retrieve for Snapshot<T>
-where T: Deref<Target=DB>,
-{
-    fn schema(&self) -> Result<Option<Schema>, Box<Error>> {
-        match self.deref().get(b"data-schema")? {
-            Some(value) => Ok(Some(Schema::read_from(&*value)?)),
-            None => Ok(None),
-        }
-    }
-
-    fn data_index(&self) -> Result<PositiveBlob, Box<Error>> {
-        match self.deref().get(b"data-index")? {
-            Some(value) => Ok(bincode::deserialize(&value)?),
-            None => Ok(PositiveBlob::default()),
-        }
-    }
-
-    fn doc_database(&self) -> Result<DocDatabase<Self>, Box<Error>> {
-        let schema = match self.schema()? {
-            Some(schema) => schema,
-            None => return Err(String::from("BUG: could not find schema").into()),
-        };
-
-        Ok(DocDatabase {
-            retrieve: self,
-            schema: schema,
-        })
-    }
-}
diff --git a/src/tokenizer/mod.rs b/src/tokenizer/mod.rs
index 58ef52d5c..9b075786b 100644
--- a/src/tokenizer/mod.rs
+++ b/src/tokenizer/mod.rs
@@ -1,52 +1,6 @@
 use std::mem;
 use self::Separator::*;
 
-struct MegaTokenizer<I> {
-    strings: I,
-}
-
-impl From<String> for MegaTokenizer<Option<String>> {
-    fn from(string: String) -> Self {
-        MegaTokenizer { strings: Some(string) }
-    }
-}
-
-impl From<Vec<String>> for MegaTokenizer<Vec<String>> {
-    fn from(strings: Vec<String>) -> Self {
-        MegaTokenizer { strings }
-    }
-}
-
-impl<I> Iterator for MegaTokenizer<I> {
-    type Item = (usize, String);
-
-    fn next(&mut self) -> Option<Self::Item> {
-        unimplemented!()
-    }
-}
-
-#[test]
-fn xxx() {
-    let s1 = "hello world!";
-    let mut s1 = MegaTokenizer::from(s1.to_owned());
-
-    assert_eq!(s1.next(), Some((0, "hello".into())));
-    assert_eq!(s1.next(), Some((1, "world".into())));
-
-    assert_eq!(s1.next(), None);
-
-    let v1 = vec!["Vin Diesel".to_owned(), "Quentin Tarantino".to_owned()];
-    let mut v1 = MegaTokenizer::from(v1);
-
-    assert_eq!(v1.next(), Some((0, "Vin".into())));
-    assert_eq!(v1.next(), Some((1, "Diesel".into())));
-
-    assert_eq!(v1.next(), Some((8, "Quentin".into())));
-    assert_eq!(v1.next(), Some((9, "Tarantino".into())));
-
-    assert_eq!(v1.next(), None);
-}
-
 pub trait TokenizerBuilder {
     fn build<'a>(&self, text: &'a str) -> Box<Iterator<Item=(usize, &'a str)> + 'a>;
 }