Fix Strava callback build-time Convex client initialization

Author: prazgaitis

.claude/napkin.md

@@ -40,3 +40,4 @@
 | 2026-02-13 | self | Used backticks inside a double-quoted `gh pr create --body` string, triggering shell command substitution and noisy side effects | Use a heredoc/file for PR body or avoid backticks in shell-quoted strings |
 ## User Preferences
 - Always commit `.claude/napkin.md` with related task commits.
+- Avoid module-scope `new ConvexHttpClient(process.env.NEXT_PUBLIC_CONVEX_URL!)` in route handlers; lazy-init inside request handlers with env guards to prevent build-time crashes.

apps/web/app/api/strava/callback/route.ts

@@ -4,7 +4,6 @@ import { api } from "@repo/backend";
 
 import { getServerAuth } from "@/lib/server-auth";
 
-const convex = new ConvexHttpClient(process.env.NEXT_PUBLIC_CONVEX_URL!);
 const STATE_COOKIE = "strava_oauth_state";
 const DEFAULT_SUCCESS_URL = "/integrations?success=strava_connected";
 const DEFAULT_ERROR_URL = "/integrations?error=strava_auth_failed";
@@ -38,6 +37,13 @@ interface StravaTokenResponse {
 }
 
 export async function GET(request: NextRequest) {
+  const convexUrl = process.env.NEXT_PUBLIC_CONVEX_URL;
+  if (!convexUrl) {
+    console.error("Missing NEXT_PUBLIC_CONVEX_URL for Strava callback route");
+    return redirectWithCookieClear(request, DEFAULT_ERROR_URL, true);
+  }
+  const convex = new ConvexHttpClient(convexUrl);
+
   const { userId, convexToken } = await getServerAuth();
 
   if (!userId) {

tasks/2026-02-13-vercel-build-convex-url.md

@@ -0,0 +1,5 @@
+# 2026-02-13 Fix Vercel build failure for Strava callback route
+
+- [x] Identify build-time crash source in `/api/strava/callback`
+- [x] Prevent module-scope Convex client initialization without env vars
+- [x] Validate with typecheck