diff --git a/src/engine/Engine.js b/src/engine/Engine.js
index d1c0201..d9095a0 100644
--- a/src/engine/Engine.js
+++ b/src/engine/Engine.js
@@ -283,15 +283,15 @@ class Engine {
         const hydrateModelList = async (property, modelToProcess, name) => {
             const subModelClass = getSubModelClass(modelToProcess, name, true);
 
-            const newModelList = await Promise.all(property.map(async subModel => {
+            const newModelList = await Promise.all(property.map(subModel => {
                 if (hydratedModels[subModel.id]) {
                     return hydratedModels[subModel.id];
                 }
 
-                return await this.get(subModelClass, subModel.id);
+                return this.get(subModelClass, subModel.id);
             }));
 
-            return await Promise.all(newModelList.map(async subModel => {
+            return Promise.all(newModelList.map(async subModel => {
                 if (hydratedModels[subModel.id]) {
                     return hydratedModels[subModel.id];
                 }
@@ -312,7 +312,7 @@ class Engine {
             return isArray ? constructorField._items : constructorField;
         }
 
-        return await hydrateModel(await this.get(model.constructor, model.id));
+        return hydrateModel(await this.get(model.constructor, model.id));
     }
 
     /**
diff --git a/src/engine/HTTPEngine.js b/src/engine/HTTPEngine.js
index 8e63615..841ceb6 100644
--- a/src/engine/HTTPEngine.js
+++ b/src/engine/HTTPEngine.js
@@ -126,7 +126,7 @@ class HTTPEngine extends Engine {
      *
      * @throws {HTTPRequestFailedError} Thrown if the fetch request fails.
      */
-    static async getById(id) {
+    static getById(id) {
         this.checkConfiguration();
 
         const url = new URL([
@@ -135,7 +135,7 @@ class HTTPEngine extends Engine {
             `${id}.json`,
         ].filter(e => Boolean(e)).join('/'));
 
-        return await this._processFetch(url, this._getReadOptions());
+        return this._processFetch(url, this._getReadOptions());
     }
 
     /**
@@ -177,7 +177,7 @@ class HTTPEngine extends Engine {
                 '_index.json',
             ].filter(e => Boolean(e)).join('/'));
 
-            return await this._processFetch(url, {
+            return this._processFetch(url, {
                 ...this._getWriteOptions(),
                 body: JSON.stringify({
                     ...await this.getIndex(location),
@@ -199,7 +199,7 @@ class HTTPEngine extends Engine {
      * @param {Model.constructor?} model - The model in the host where the index is stored.
      * @returns {Promise<Object>} The index data in JSON format.
      */
-    static async getIndex(model) {
+    static getIndex(model) {
         const url = new URL([
             this.configuration.host,
             this.configuration.prefix,
@@ -207,7 +207,7 @@ class HTTPEngine extends Engine {
             '_index.json',
         ].filter(e => Boolean(e)).join('/'));
 
-        return await this._processFetch(url, this._getReadOptions(), {});
+        return this._processFetch(url, this._getReadOptions(), {});
     }
 
     /**
@@ -216,7 +216,7 @@ class HTTPEngine extends Engine {
      * @param {Model.constructor} model - The model whose compiled search index to retrieve.
      * @returns {Promise<Object>} The compiled search index in JSON format.
      */
-    static async getSearchIndexCompiled(model) {
+    static getSearchIndexCompiled(model) {
         const url = new URL([
             this.configuration.host,
             this.configuration.prefix,
@@ -224,7 +224,7 @@ class HTTPEngine extends Engine {
             '_search_index.json',
         ].join('/'));
 
-        return await this._processFetch(url, this._getReadOptions());
+        return this._processFetch(url, this._getReadOptions());
     }
 
     /**
@@ -233,7 +233,7 @@ class HTTPEngine extends Engine {
      * @param {Model.constructor} model - The model whose raw search index to retrieve.
      * @returns {Promise<Object>} The raw search index in JSON format, or an empty object if not found.
      */
-    static async getSearchIndexRaw(model) {
+    static getSearchIndexRaw(model) {
         const url = new URL([
             this.configuration.host,
             this.configuration.prefix,
@@ -241,7 +241,7 @@ class HTTPEngine extends Engine {
             '_search_index_raw.json',
         ].join('/'));
 
-        return await this._processFetch(url, this._getReadOptions()).catch(() => ({}));
+        return this._processFetch(url, this._getReadOptions()).catch(() => ({}));
     }
 
     /**
@@ -253,7 +253,7 @@ class HTTPEngine extends Engine {
      *
      * @throws {HTTPRequestFailedError} Thrown if the PUT request fails.
      */
-    static async putSearchIndexCompiled(model, compiledIndex) {
+    static putSearchIndexCompiled(model, compiledIndex) {
         const url = new URL([
             this.configuration.host,
             this.configuration.prefix,
@@ -276,7 +276,7 @@ class HTTPEngine extends Engine {
      *
      * @throws {HTTPRequestFailedError} Thrown if the PUT request fails.
      */
-    static async putSearchIndexRaw(model, rawIndex) {
+    static putSearchIndexRaw(model, rawIndex) {
         const url = new URL([
             this.configuration.host,
             this.configuration.prefix,
@@ -284,7 +284,7 @@ class HTTPEngine extends Engine {
             '_search_index_raw.json',
         ].filter(e => Boolean(e)).join('/'));
 
-        return await this._processFetch(url, {
+        return this._processFetch(url, {
             ...this._getWriteOptions(),
             body: JSON.stringify(rawIndex),
         });
diff --git a/src/engine/S3Engine.js b/src/engine/S3Engine.js
index 8dba80c..0637ed5 100644
--- a/src/engine/S3Engine.js
+++ b/src/engine/S3Engine.js
@@ -153,9 +153,9 @@ class S3Engine extends Engine {
      * @param {Model.constructor} model - The model whose search index to retrieve.
      * @returns {Promise<Object>} The compiled search index.
      */
-    static async getSearchIndexCompiled(model) {
-        return await this.configuration.client.send(new GetObjectCommand({
-            Key: [this.configuration.prefix, model.name, '_search_index.json'].join('/'),
+    static getSearchIndexCompiled(model) {
+        return this.configuration.client.send(new GetObjectCommand({
+            Key: [this.configuration.prefix, model.toString(), '_search_index.json'].join('/'),
             Bucket: this.configuration.bucket,
         })).then(data => data.Body.transformToString())
             .then(JSON.parse);
@@ -167,8 +167,8 @@ class S3Engine extends Engine {
      * @param {Model.constructor} model - The model whose raw search index to retrieve.
      * @returns {Promise<Object>} The raw search index, or an empty object if not found.
      */
-    static async getSearchIndexRaw(model) {
-        return await this.configuration.client.send(new GetObjectCommand({
+    static getSearchIndexRaw(model) {
+        return this.configuration.client.send(new GetObjectCommand({
             Key: [this.configuration.prefix, model.toString(), '_search_index_raw.json'].join('/'),
             Bucket: this.configuration.bucket,
         })).then(data => data.Body.transformToString())