diff --git a/routes/github/commits.ts b/routes/github/commits.ts
index 125ca04f..8099421e 100644
--- a/routes/github/commits.ts
+++ b/routes/github/commits.ts
@@ -2,9 +2,13 @@ import { Request, Response } from "express";
 import { seconds } from "../../utils/misc.js";
 import { getCommits } from "./lib/commits.js";
 
-export default async function route(req: Request, res: Response) {
+type Params = { org: string; repo: string };
+type Query = { from: string; to?: string; path?: string };
+type IRequest = Request<Params, any, any, Query>;
+
+export default async function route(req: IRequest, res: Response) {
   const { org, repo } = req.params;
-  const { from, to , path } = req.query;
+  const { from, to, path } = req.query;
   if (!from || typeof from !== "string") {
     res.set("Content-Type", "text/plain");
     return res.status(400).send("query parameter 'from' is required");
@@ -32,6 +36,7 @@ export default async function route(req: Request, res: Response) {
     }
     res.json(commits);
   } catch (error) {
+    res.set("Content-Type", "text/plain");
     res.status(404).send(error.message);
   }
 }
diff --git a/routes/github/contributors.ts b/routes/github/contributors.ts
index eadcc423..aa53e8c7 100644
--- a/routes/github/contributors.ts
+++ b/routes/github/contributors.ts
@@ -12,7 +12,10 @@ const cache = new DiskCache<null | Contributors>({
   path: "github/contributors",
 });
 
-export default async function route(req: Request, res: Response) {
+type Params = { org: string; repo: string };
+type IRequest = Request<Params>;
+
+export default async function route(req: IRequest, res: Response) {
   const { org, repo } = req.params;
   const cacheKey = `${org}/${repo}`;
 
diff --git a/routes/w3c/group.ts b/routes/w3c/group.ts
index 677ae957..1665c840 100644
--- a/routes/w3c/group.ts
+++ b/routes/w3c/group.ts
@@ -39,7 +39,10 @@ const LEGACY_SHORTNAMES = new Map([
   ["i18n", "i18n-core"], // more than 10 instances
 ]);
 
-export default async function route(req: Request, res: Response) {
+type Params = { shortname?: string; type?: string };
+type IRequest = Request<Params>;
+
+export default async function route(req: IRequest, res: Response) {
   const { shortname, type } = req.params;
   if (!shortname) {
     if (req.headers.accept?.includes("text/html")) {
@@ -57,7 +60,7 @@ export default async function route(req: Request, res: Response) {
   }
 
   try {
-    const requestedType = type as GroupType;
+    const requestedType = type as GroupType | undefined;
     const groupInfo = await getGroupInfo(shortname, requestedType);
     res.set("Cache-Control", `max-age=${seconds("24h")}`);
     res.json(groupInfo);
@@ -70,7 +73,7 @@ export default async function route(req: Request, res: Response) {
 
 async function getGroupInfo(
   shortname: GroupMeta["name"],
-  requestedType: GroupType,
+  requestedType?: GroupType,
 ) {
   const cacheKey = `${shortname}/${requestedType || ""}`;
   if (cache.expires(cacheKey) > 1000) {
@@ -160,7 +163,7 @@ async function getPatentPolicy(
   }
 }
 
-function getGroupMeta(shortname: string, requestedType: GroupType) {
+function getGroupMeta(shortname: string, requestedType?: GroupType) {
   const types = requestedType
     ? [requestedType]
     : (Object.keys(groups) as GroupType[]);
diff --git a/routes/w3c/index.ts b/routes/w3c/index.ts
index 4830f686..4a809574 100644
--- a/routes/w3c/index.ts
+++ b/routes/w3c/index.ts
@@ -4,6 +4,6 @@ import cors from "cors";
 import groupsRoute from "./group.js";
 
 const w3c = Router();
-w3c.get("/groups/:shortname?/:type?", cors(), groupsRoute);
+w3c.get("/groups{/:shortname}{/:type}", cors(), groupsRoute);
 
 export default w3c;
diff --git a/routes/xref/index.ts b/routes/xref/index.ts
index 50c31e23..7faf4ed9 100644
--- a/routes/xref/index.ts
+++ b/routes/xref/index.ts
@@ -25,7 +25,7 @@ xref
   .options("/search", cors({ methods: ["POST", "GET"], maxAge: ms("1day") }))
   .get("/search", cors(), searchRouteGet)
   .post("/search", express.json({ limit: "2mb" }), cors(), searchRoutePost);
-xref.get("/meta/:field?", cors(), metaRoute);
+xref.get("/meta{/:field}", cors(), metaRoute);
 xref.post("/update", authGithubWebhook(env("W3C_WEBREF_SECRET")), updateRoute);
 xref.use("/data", express.static(path.join(DATA_DIR, "xref")));
 
diff --git a/scripts/update-w3c-groups-list.ts b/scripts/update-w3c-groups-list.ts
index 7ace808e..6a238568 100644
--- a/scripts/update-w3c-groups-list.ts
+++ b/scripts/update-w3c-groups-list.ts
@@ -75,7 +75,7 @@ export default async function update() {
       case "group":
         return g;
       case "tf":
-        return g.members;
+        return g.members || [];
       default:
         return [];
     }