diff --git a/registry/src/http/api.ts b/registry/src/http/api.ts
index 4ec9b55..bcaa66f 100644
--- a/registry/src/http/api.ts
+++ b/registry/src/http/api.ts
@@ -8,7 +8,7 @@ import db, { IPackage } from "../db.ts";
 import { v4 } from "https://deno.land/std/uuid/mod.ts";
 
 export default function api(g: ABC.Group) {
-   const cacheControl = (next) => (ctx) => {
+   const cacheControl = (next: ABC.HandlerFunc) => (ctx: ABC.Context) => {
       ctx.response.headers.set("cache-control", "private");
       next(ctx);
    };