Hi, I'm trying to build my Astro project using Cloudflare Workers build, but during the site build, it makes multiple web requests to fetch images. On a local development environment, this works just fine, and indeed I can manually load the URLs it's attempting to hit.
In the worker build, however, I get the following error:
18:37:20.568 18:37:20 ├─ /~sink/blog/2025/10/vr-streamers/index.html (+287ms) 18:37:30.951 fetch failed18:37:30.951 Hint:18:37:30.951 This issue often occurs when your MDX component encounters runtime errors.18:37:30.951 Stack trace:18:37:30.951 at node:internal/deps/undici/undici:13510:1318:37:30.951 at runNextTicks (node:internal/process/task_queues:69:3)18:37:30.951 at async getSizeImpl (file:///opt/buildhome/repo/dist/chunks/FlexImg_BkrOVuPy.mjs:31:45)18:37:30.951 Caused by:18:37:30.951 Connect Timeout Error (attempted address: i.uwu.network:443, timeout: 10000ms)18:37:30.951 at onConnectTimeout (node:internal/deps/undici/undici:2602:28)18:37:30.951 at process.processImmediate (node:internal/timers:485:21)18:37:31.075 18:37:20 ├─ /~sink/blog/2025/12/2025/index.html ELIFECYCLE Command failed with exit code 1.18:37:31.102 Failed: error occurred while running build command
18:37:20.568 18:37:20 ├─ /~sink/blog/2025/10/vr-streamers/index.html (+287ms) 18:37:30.951 fetch failed18:37:30.951 Hint:18:37:30.951 This issue often occurs when your MDX component encounters runtime errors.18:37:30.951 Stack trace:18:37:30.951 at node:internal/deps/undici/undici:13510:1318:37:30.951 at runNextTicks (node:internal/process/task_queues:69:3)18:37:30.951 at async getSizeImpl (file:///opt/buildhome/repo/dist/chunks/FlexImg_BkrOVuPy.mjs:31:45)18:37:30.951 Caused by:18:37:30.951 Connect Timeout Error (attempted address: i.uwu.network:443, timeout: 10000ms)18:37:30.951 at onConnectTimeout (node:internal/deps/undici/undici:2602:28)18:37:30.951 at process.processImmediate (node:internal/timers:485:21)18:37:31.075 18:37:20 ├─ /~sink/blog/2025/12/2025/index.html ELIFECYCLE Command failed with exit code 1.18:37:31.102 Failed: error occurred while running build command
. URLs under this address hit a server that serves a redirect to cdn.hyrule.pics, which itself is a Cloudflare Worker that serves a file. Why exactly this error consistently occurs I do not know - the build troubleshooting page does not mention any restriction on making network requests in builds.