diff --git a/README.md b/README.md
index b7ce998..031400f 100644
--- a/README.md
+++ b/README.md
@@ -117,7 +117,7 @@ commands together that share the same environment variables.
 ### Asynchronous env file support
 
 EnvCmd supports reading from asynchronous `.env` files. Instead of using a `.env` file, pass in a `.js`
-file that returns a `Promise` resolving to an object (`{ ENV_VAR_NAME: value, ... }`). Asynchronous `.rc`
+file that exports either an object or a `Promise` resolving to an object (`{ ENV_VAR_NAME: value, ... }`). Asynchronous `.rc`
 files are also supported using `.js` file extension and resolving to an object with top level environment
 names (`{ production: { ENV_VAR_NAME: value, ... } }`).
 
@@ -212,4 +212,4 @@ added. Before opening a PR please make sure to run the following scripts:
 
 - `npm run lint` checks for code errors and format according to [js-standard](https://github.com/feross/standard)
 - `npm test` make sure all tests pass
-- `npm run test-cover` make sure the coverage has not decreased from current master
\ No newline at end of file
+- `npm run test-cover` make sure the coverage has not decreased from current master