diff --git a/meilisearch-core/src/update/settings_update.rs b/meilisearch-core/src/update/settings_update.rs
index da9d23047..499bdca35 100644
--- a/meilisearch-core/src/update/settings_update.rs
+++ b/meilisearch-core/src/update/settings_update.rs
@@ -197,8 +197,6 @@ pub fn apply_stop_words_update(
         )?;
     }
 
-    main_store.put_stop_words(writer, stop_words)?;
-
     Ok(must_reindex)
 }
 
@@ -341,7 +339,6 @@ pub fn apply_synonyms_update(
         .unwrap();
 
     main_store.put_synonyms_fst(writer, &synonyms_set)?;
-    main_store.put_synonyms(writer, synonyms)?;
 
     Ok(())
 }
diff --git a/meilisearch-http/Cargo.toml b/meilisearch-http/Cargo.toml
index 61c34b5e7..64dd2ba17 100644
--- a/meilisearch-http/Cargo.toml
+++ b/meilisearch-http/Cargo.toml
@@ -19,7 +19,6 @@ bincode = "1.2.0"
 chrono = { version = "0.4.9", features = ["serde"] }
 crossbeam-channel = "0.4.0"
 env_logger = "0.7.1"
-fst = { version = "0.3.5", default-features = false }
 heed = "0.6.1"
 http = "0.1.19"
 indexmap = { version = "1.3.0", features = ["serde-1"] }
@@ -46,6 +45,7 @@ whoami = "0.6"
 http-service-mock = "0.4.0"
 http-service = "0.4.0"
 tempdir = "0.3.7"
+assert-json-diff = "1.0.1"
 
 [build-dependencies]
 vergen = "3.0.4"
diff --git a/meilisearch-http/src/error.rs b/meilisearch-http/src/error.rs
index 220519231..23f2765f9 100644
--- a/meilisearch-http/src/error.rs
+++ b/meilisearch-http/src/error.rs
@@ -137,8 +137,8 @@ impl From<heed::Error> for ResponseError {
     }
 }
 
-impl From<fst::Error> for ResponseError {
-    fn from(err: fst::Error) -> ResponseError {
+impl From<meilisearch_core::FstError> for ResponseError {
+    fn from(err: meilisearch_core::FstError) -> ResponseError {
         ResponseError::internal(err)
     }
 }
@@ -149,7 +149,6 @@ impl From<SearchError> for ResponseError {
     }
 }
 
-
 pub trait IntoInternalError<T> {
     fn into_internal_error(self) -> SResult<T>;
 }
@@ -159,7 +158,7 @@ impl <T> IntoInternalError<T> for Option<T> {
     fn into_internal_error(self) -> SResult<T> {
         match self {
             Some(value) => Ok(value),
-            None => Err(ResponseError::internal("Heed "))
+            None => Err(ResponseError::internal("Heed cannot find requested value"))
         }
     }
 }