And that should be it

src/env.d.ts

@@ -0,0 +1,6 @@
+declare module "bun" {
+    interface Env {
+        DISCORD_CLIENT_ID: string;
+        DISCORD_CLIENT_SECRET: string;
+    }
+}

src/index.ts

@@ -1 +1,11 @@
-console.log("Hello via Bun!");
+import token from "./routes/token";
+
+Bun.serve({
+    port: 3000,
+    async fetch(req) {
+        const url = new URL(req.url);
+        if (url.pathname === "/") return new Response("hello yes this is garf");
+        if (url.pathname === "/api/token") return await token(req);
+        return new Response("garf dont know what want...");
+    },
+});

src/routes/token.ts

@@ -0,0 +1,35 @@
+interface TokenRequest {
+    code: string;
+}
+
+interface TokenResponse {
+    access_token: string;
+    token_type: string;
+    expires_in: number;
+    refresh_token: string;
+    scope: string;
+}
+
+export default async function (req: Request): Promise<Response> {
+    if (req.method !== "post") return new Response("garf expected a POST request...");
+    if (!req.headers.get("Content-Type")) return new Response("garf expected some jay sawn...");
+    if (!req.headers.get("Content-Type")?.includes("application/json")) return new Response("garf expected some jay sawn...");
+
+    const body = (await req.json()) as TokenRequest;
+    if (!body) return new Response("garf expected some jay sawn...");
+
+    const response = await fetch("https://discord.com/api/oauth2/token", {
+        method: "POST",
+        headers: { "Content-Type": "application/x-www-form-urlencoded" },
+        body: new URLSearchParams({
+            client_id: process.env.DISCORD_CLIENT_ID,
+            client_secret: process.env.DISCORD_CLIENT_SECRET,
+            grant_type: "authorization_code",
+            code: body?.code,
+        }),
+    });
+
+    const { access_token } = (await response.json()) as TokenResponse;
+
+    return new Response(access_token);
+}