diff --git a/test/tsconfig.json b/test/tsconfig.json
new file mode 100644
index 0000000..8957991
--- /dev/null
+++ b/test/tsconfig.json
@@ -0,0 +1,10 @@
+{
+  "compilerOptions": {
+    "module": "commonjs",
+    "target": "es2017",
+    "strictNullChecks": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true
+  },
+  "include": ["*"]
+}
diff --git a/test/type_test.ts b/test/type_test.ts
index 8ad692b..120ae0a 100644
--- a/test/type_test.ts
+++ b/test/type_test.ts
@@ -1,50 +1,58 @@
 import ArSyncModel from './generated_typed_files/ArSyncModel'
 import { useArSyncModel, useArSyncFetch } from './generated_typed_files/hooks'
 
+type IsEqual<T, U> = [T, U] extends [U, T] ? true : false
+function isOK<T extends true>(): T | undefined { return }
+type IsStrictMode = string | null extends string ? false : true
+isOK<IsStrictMode>()
+
 const [hooksData1] = useArSyncModel({ field: 'currentUser', query: 'id' })
-hooksData1!.id
+isOK<IsEqual<typeof hooksData1, { id: number } | null>>()
 const [hooksData2] = useArSyncModel({ field: 'currentUser', query: { '*': true, foo: true } })
-hooksData2!.error.extraFields = 'foo'
+isOK<IsEqual<typeof hooksData2, { error: { extraFields: 'foo' } } | null>>()
 const [hooksData3] = useArSyncFetch({ field: 'currentUser', query: 'id' })
-hooksData3!.id
+isOK<IsEqual<typeof hooksData3, { id: number } | null>>()
 const [hooksData4] = useArSyncFetch({ field: 'currentUser', query: { '*': true, foo: true } })
-hooksData4!.error.extraFields = 'foo'
+isOK<IsEqual<typeof hooksData4, { error: { extraFields: 'foo' } } | null>>()
 
 const data1 = new ArSyncModel({ field: 'currentUser', query: 'id' }).data!
-data1.id
+isOK<IsEqual<typeof data1, { id: number }>>()
 const data2 = new ArSyncModel({ field: 'currentUser', query: ['id', 'name'] }).data!
-data2.id; data2.name
+isOK<IsEqual<typeof data2, { id: number; name: string | null }>>()
 const data3 = new ArSyncModel({ field: 'currentUser', query: '*' }).data!
-data3.id; data3.name; data3.posts
+isOK<IsEqual<typeof data3, { id: number; name: string | null; posts: {}[]; do_not_call_after_destroyed: any }>>()
 const data4 = new ArSyncModel({ field: 'currentUser',  query: { posts: 'id' } }).data!
-data4.posts[0].id
+isOK<IsEqual<typeof data4, { posts: { id: number }[] }>>()
 const data5 = new ArSyncModel({ field: 'currentUser', query: { posts: '*' } }).data!
-data5.posts[0].id; data5.posts[0].user; data5.posts[0].body
-const data6 = new ArSyncModel({ field: 'currentUser', query: { posts: { '*': true, comments: 'user' } } }).data!
-data6.posts[0].id; data6.posts[0].user; data6.posts[0].comments[0].user
+isOK<IsEqual<typeof data5, {
+  posts: {
+    id: number; user: {}; title: string | null; body: string | null;
+    do_not_call_after_destroyed: any; comments: {}[]; my_comments: {}[]
+  }[]
+}>>()
+const data6 = new ArSyncModel({ field: 'currentUser', query: { posts: { '*': true, comments: 'user' } } }).data!.posts[0].comments[0]
+isOK<IsEqual<typeof data6, { user: {} }>>()
 const data7 = new ArSyncModel({ field: 'currentUser', query: { name: true, poosts: true } }).data!
-data7.error.extraFields = 'poosts'
+isOK<IsEqual<typeof data7, { error: { extraFields: 'poosts' } }>>()
 const data8 = new ArSyncModel({ field: 'currentUser', query: { posts: { id: true, commmments: true, titllle: true } } }).data!
-data8.error.extraFields = 'commmments'
-data8.error.extraFields = 'titllle'
+isOK<IsEqual<typeof data8, { error: { extraFields: 'commmments' | 'titllle' } }>>()
 const data9 = new ArSyncModel({ field: 'currentUser', query: { '*': true, posts: { id: true, commmments: true } } }).data!
-data9.error.extraFields = 'commmments'
-const data10 = new ArSyncModel({ field: 'users', query: { '*': true, posts: { id: true, comments: '*' } } }).data!
-data10[0].posts[0].comments[0].id
+isOK<IsEqual<typeof data9, { error: { extraFields: 'commmments' } }>>()
+const data10 = new ArSyncModel({ field: 'users', query: { '*': true, posts: { id: true, comments: '*' } } }).data![0].posts[0].comments[0].id
+isOK<IsEqual<typeof data10, number>>()
 const data11 = new ArSyncModel({ field: 'users', query: { '*': true, posts: { id: true, comments: '*', commmments: true } } }).data!
-data11.error.extraFields = 'commmments'
-const data12 = new ArSyncModel({ field: 'currentUser', query: { posts: { params: { limit: 4 }, query: 'title' } } }).data!
-data12.posts[0].title
-const data13 = new ArSyncModel({ field: 'currentUser', query: { posts: { params: { limit: 4 }, query: ['id', 'title'] } } }).data!
-data13.posts[0].title
-const data14 = new ArSyncModel({ field: 'currentUser', query: { posts: { params: { limit: 4 }, query: { id: true, title: true } } } }).data!
-data14.posts[0].title
-const data15 = new ArSyncModel({ field: 'currentUser', query: { posts: ['id', 'title'] } } as const).data!
-data15.posts[0].title
+isOK<IsEqual<typeof data11, { error: { extraFields: 'commmments' } }>>()
+const data12 = new ArSyncModel({ field: 'currentUser', query: { posts: { params: { limit: 4 }, query: 'title' } } }).data!.posts[0]
+isOK<IsEqual<typeof data12, { title: string | null }>>()
+const data13 = new ArSyncModel({ field: 'currentUser', query: { posts: { params: { limit: 4 }, query: ['id', 'title'] } } }).data!.posts[0]
+isOK<IsEqual<typeof data13, { id: number; title: string | null }>>()
+const data14 = new ArSyncModel({ field: 'currentUser', query: { posts: { params: { limit: 4 }, query: { id: true, title: true } } } }).data!.posts[0]
+isOK<IsEqual<typeof data14, { id: number; title: string | null }>>()
+const data15 = new ArSyncModel({ field: 'currentUser', query: { posts: ['id', 'title'] } } as const).data!.posts[0]
+isOK<IsEqual<typeof data15, { id: number; title: string | null }>>()
 
 const data16 = new ArSyncModel({ field: 'currentUser', query: { id: { field: 'name' }, name: { field: 'id' }, id2: { field: 'id' }, name2: { field: 'name' } } }).data!
-data16.name = data16.id2 = 0
-data16.id = data16.name2 = 'name'
-const data17 = new ArSyncModel({ field: 'currentUser', query: { posts: { '*': true, hoge: { field: 'comments', query: 'id' }, comments: { field: 'title' } } } }).data!
-data17.posts[0].comments = 'title'
-data17.posts[0].hoge[0].id = 0
+isOK<IsEqual<typeof data16, { id: string | null; name: number; id2: number; name2: string | null }>>()
+const data17 = new ArSyncModel({ field: 'currentUser', query: { posts: { '*': true, hoge: { field: 'comments', query: 'id' }, comments: { field: 'title' } } } }).data!.posts[0]
+isOK<IsEqual<typeof data17.hoge, { id: number }[]>>()
+isOK<IsEqual<typeof data17.comments, string | null>>()