Is Go module proxy Down? How to Check and Keep Your CI Green

By Daniel Zoghalchali·Latchkey

Your CI just went red and you suspect Go module proxy. Here is how to confirm an outage in seconds - and how to stop a proxy blip from failing your builds in the first place.

When Go module proxy has a hiccup, every pipeline that pulls from it can fail at once. The good news: these failures are transient, so the fix is to confirm the outage and make your CI resilient to it.

How to check if Go module proxy is down

1. Check the official status page: status.proxy.golang.org
2. Look for an active incident affecting proxy.golang.org or the checksum database.
3. Cross-check community reports (Downdetector, the project's status on social/X).
4. Confirm it is org-wide, not just your job: if every repo pulling from Go module proxy fails at once, it is an outage, not your config.

What it looks like in CI

An outage usually surfaces as a transient network or 5xx error while fetching from Go module proxy:

go: downloading ... dial tcp: i/o timeout
verifying module: ... 503 Service Unavailable

Outage vs your own bug

• Outage: many repos fail at once, errors are network/5xx/timeouts, no recent change on your side.
• Your bug: one repo, a specific error, started right after a change you made.

How to keep CI green during a blip

• Add retry-with-backoff around the step that hits Go module proxy - most blips pass within a minute.
• Set a fallback GOPROXY (or run an Athens proxy) and use the module cache.
• Cache dependencies so a brief outage does not block jobs that could install from cache.
• Avoid mass "re-run all" during an incident - it piles up when the service recovers.

Key takeaways

• Check status.proxy.golang.org first; org-wide failures = outage, not your config.
• Go module proxy blips are transient network/5xx errors.
• Retries, caching, and a mirror keep CI green through a hiccup.

Frequently asked questions

Related guides

References

• GitHub Actions documentation