diff --git a/flow-custom-typedefs/process-exists.js b/flow-custom-typedefs/process-exists.js
new file mode 100644
index 0000000..9007873
--- /dev/null
+++ b/flow-custom-typedefs/process-exists.js
@@ -0,0 +1,3 @@
+declare module 'process-exists' {
+  declare module.exports: string => Promise<boolean>;
+}