diff --git a/tsconfig.build.json b/tsconfig.build.json
index a54c6bb..143410b 100644
--- a/tsconfig.build.json
+++ b/tsconfig.build.json
@@ -1,6 +1,6 @@
 {
   "extends": "./tsconfig.json",
-  "exclude": ["node_modules", "__tests__"],
+  "include": ["src"],
   "compilerOptions": {
     "outDir": "./lib" /* Redirect output structure to the directory. */,
     "rootDir": "./src" /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */