diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 0000000..4766d36
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,31 @@
+declare module "octokit-commit-multiple-files" {
+  import { Octokit } from "@octokit/rest";
+
+  declare function plugin(octokit: Octokit);
+}
+
+declare module "octokit-commit-multiple-files/create-or-update-files" {
+  import { Octokit } from "@octokit/rest";
+
+  type BufferFromSource =
+    | arrayBuffer
+    | Uint8Array
+    | ReadonlyArray<number>
+    | WithImplicitCoercion<Uint8Array | ReadonlyArray<number> | string>
+    | WithImplicitCoercion<string>
+    | { [Symbol.toPrimitive](hint: "string"): string };
+
+  interface CreateOrUpdateFilesOptions {
+    owner: string;
+    repo: string;
+    branch: string;
+    changes: Array<{
+      message: string;
+      files: {
+        [path: string]: string | BufferFromSource | { contents: string | BufferFromSource };
+      };
+    }>;
+  }
+
+  export default function createOrUpdateFiles(octokit: Octokit, opts: CreateOrUpdateFilesOptions);
+}