diff --git a/index.d.ts b/index.d.ts
index 30bd960..31e906a 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,4 +1,7 @@
-import {PackageJson} from 'type-fest';
+import {
+	CamelCasedProperties,
+	PackageJson,
+} from 'type-fest';
 
 export type FlagType = 'string' | 'boolean' | 'number';
 
@@ -246,7 +249,7 @@ export interface Result<Flags extends AnyFlags> {
 	/**
 	Flags converted to camelCase excluding aliases.
 	*/
-	flags: TypedFlags<Flags> & Record<string, unknown>;
+	flags: CamelCasedProperties<TypedFlags<Flags>> & Record<string, unknown>;
 
 	/**
 	Flags converted camelCase including aliases.
diff --git a/index.test-d.ts b/index.test-d.ts
index 81463b3..1677e6b 100644
--- a/index.test-d.ts
+++ b/index.test-d.ts
@@ -64,7 +64,7 @@ expectType<PackageJson>(result.pkg);
 expectType<string>(result.help);
 
 expectType<boolean | undefined>(result.flags.foo);
-expectType<unknown>(result.flags.fooBar);
+expectType<number | undefined>(result.flags.fooBar);
 expectType<string>(result.flags.bar);
 expectType<string[] | undefined>(result.flags.abc);
 expectType<boolean | undefined>(result.unnormalizedFlags.foo);
diff --git a/package.json b/package.json
index d4e20bb..f7890b8 100644
--- a/package.json
+++ b/package.json
@@ -52,7 +52,7 @@
 		"read-pkg-up": "^8.0.0",
 		"redent": "^4.0.0",
 		"trim-newlines": "^4.0.2",
-		"type-fest": "^1.2.2",
+		"type-fest": "^3.1.0",
 		"yargs-parser": "^20.2.9"
 	},
 	"devDependencies": {