diff --git a/package.json b/package.json
index fe2f7fc..2330368 100644
--- a/package.json
+++ b/package.json
@@ -1,20 +1,13 @@
 {
   "name": "jsonapi-fractal",
-  "version": "1.0.13",
+  "version": "1.0.16",
   "description": "JSON:API Serializer inspired by Fractal (PHP)",
   "license": "MIT",
   "main": "dist/index",
   "types": "./dist/index.d.ts",
-  "module": "./dist-esm/index.js",
-  "exports": {
-    ".": {
-      "require": "./dist/index.js",
-      "default": "./dist-esm/index.js"
-    }
-  },
   "scripts": {
     "test": "jest",
-    "build": "tsc && tsc -m es6 --outDir dist-esm",
+    "build": "tsc",
     "lint": "tslint src/**/*.ts tests/*.ts"
   },
   "jest": {
diff --git a/src/JsonApiResponse.ts b/src/JsonApiResponse.ts
new file mode 100644
index 0000000..c606314
--- /dev/null
+++ b/src/JsonApiResponse.ts
@@ -0,0 +1,5 @@
+export default interface JsonApiResponse {
+  data: any;
+  meta?: any;
+  included?: any[];
+}
diff --git a/src/index.ts b/src/index.ts
index 796b53a..a854ea8 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -4,7 +4,8 @@ import Context from './Context'
 import JsonApiError from './errors/JsonApiError'
 import DefaultTransformer from './DefaultTransformer'
 import deserialize from './deserializer'
+import JsonApiResponse from './JsonApiResponse'
 import { serializeContext, serialize, transform } from './serializer'
 import { whitelist } from './utils'
 
-export { Transformer, DefaultTransformer, transform, serialize, deserialize, whitelist }
+export { Transformer, DefaultTransformer, transform, serialize, JsonApiResponse, deserialize, whitelist, Options }
diff --git a/src/serializer.ts b/src/serializer.ts
index 2ad3ef7..40afaba 100644
--- a/src/serializer.ts
+++ b/src/serializer.ts
@@ -4,12 +4,13 @@ import Transformer from './Transformer'
 import JsonApiError from './errors/JsonApiError'
 import Options from './Options'
 import { whitelist, changeCase } from './utils'
+import JsonApiResponse from './JsonApiResponse'
 
-export function transform () {
+export function transform (): Context {
   return new Context(serializeContext);
 }
 
-export function serialize (data, type, options) {
+export function serialize (data, type, options): JsonApiResponse {
   if (!options) {
     options = {}
   }
@@ -21,7 +22,7 @@ export function serialize (data, type, options) {
     .serialize()
 }
 
-export function serializeContext (ctx: Context) {
+export function serializeContext (ctx: Context): JsonApiResponse {
   if (!ctx.options) {
     ctx.options = {};
   }
@@ -53,7 +54,7 @@ export function serializeContext (ctx: Context) {
   return result
 }
 
-function serializeEntity (entity, transformer: Transformer, options: Options, includedByType) {
+function serializeEntity (entity, transformer: Transformer, options: Options, includedByType): any {
   let attributes = { ...transformer.transform(entity, options) };
   const idKey = options.idKey || 'id';
   const id = attributes[idKey] || entity[idKey];
@@ -102,7 +103,7 @@ function serializeEntity (entity, transformer: Transformer, options: Options, in
   return data
 }
 
-function serializeRelation (entity, transformer: Transformer, options: Options, included: boolean, includedByType) {
+function serializeRelation (entity, transformer: Transformer, options: Options, included: boolean, includedByType) : any {
   if (!entity) {
     return null;
   }
diff --git a/tests/included-transform.spec.ts b/tests/included-transform.spec.ts
index 2b1deb8..b7fbed3 100644
--- a/tests/included-transform.spec.ts
+++ b/tests/included-transform.spec.ts
@@ -90,7 +90,7 @@ describe('transform', () => {
 
     const entitySerialized = transform()
       .withInput(entity)
-      .withTransformer(new UserTransformer)
+      .withTransformer(new UserTransformer())
       .withOptions({ idKey: '_id' })
       .serialize();
 
diff --git a/tslint.json b/tslint.json
index 09b2fba..cd0839e 100644
--- a/tslint.json
+++ b/tslint.json
@@ -1,6 +1,7 @@
 {
   "extends": [
     "tslint:latest",
-    "tslint-config-prettier"
+    "tslint-config-prettier",
+    "tslint:recommended"
   ]
 }