My Railway deployment is failing during the Build Image stage, before my application or dependencies are started. The build fails while mise tries to download/install Python: mise ERROR Failed to install core:python@3.11.9: error sending request: client error (SendRequest) http2 error: stream error received: refused stream before processing any application logic The same problem previously occurred with Python 3.13.14. I added a .python-version file specifying Python 3.11.9. Railway correctly detects Python 3.11.9, but the build still fails with the same HTTP2/refused stream error. I have retried the deployment multiple times with the same result. Railway's automatic Diagnosis also failed. An older deployment of the application is still ACTIVE and working correctly. Only new builds are failing. Could you please check whether there is an issue with the Railway build infrastructure or the Python/mise download process for this service?

Build fails installing Python with mise - HTTP2 refused stream

Railway

BOT

9 days ago

This thread has been opened as a bounty so the community can help solve it.

Status changed to Open Railway • 9 days ago

manuproject

HOBBY

9 days ago

failing with two different python versions (3.13.14, then 3.11.9), both correctly detected, points away from a version-pinning issue and toward the actual download step being flaky, not something in your repo. mise's install step failing mid-request like this usually means it lost the connection to wherever it's fetching the python binary from during the build, same root shape as what's reported here:

https://station.railway.com/questions/railpack-failed-python-install-9dc8f512

https://station.railway.com/questions/tcp-conn-refused-mise-5b85c7ae

two things that fixed it for others hitting the same mise/python failures: clearing the build cache (service settings → clear build cache, then redeploy), reported working here:

https://station.railway.com/questions/failed-to-build-image-mise-error-63572c77

and setting RAILPACK_PYTHON_VERSION as an env var instead of relying only on .python-version. worth trying both since it's recurring across retries for you, not a one-off blip.

darseen

HOBBYTop 5% Contributor

9 days ago

I'd recommend you use a Dockerfile setup to get rid of mise errors entirly. You can use the image FROM python:3.11.9-slim for example, and have your app set up exactly how you want, as Dockerfile setups provide more control over your builds. FWIW, you can try setting NO_CACHE=1 in your service variables to rule out any caching issues.

mehmetcanhoroz

PRO

9 days ago

Having same issue, i believe it is related to Railway system somehow. Trying to figure it out.

mehmetcanhoroz

Having same issue, i believe it is related to Railway system somehow. Trying to figure it out.

manuproject

HOBBY

9 days ago

try to open a thread about also

manuproject

try to open a thread about also

mehmetcanhoroz

PRO

9 days ago

i am trying to contact Railway, it is not something i believe community level we can fix. i will update his thread if i can get any solution :)

mehmetcanhoroz

PRO

9 days ago

Hi softeasyweb1966-web,

It was an internal issue, and you can retry now; it will work for u this time. My services are back now, and so are yours. Let me know, and I will try to find a way as well :)

edgnkv

EMPLOYEE

8 days ago

Hello,

We had intermittent connectivity issues to Github, should be resolved now.

Status changed to Awaiting User Response Railway • 8 days ago

mehmetcanhoroz

Hi softeasyweb1966-web, It was an internal issue, and you can retry now; it will work for u this time. My services are back now, and so are yours. Let me know, and I will try to find a way as well :)

softeasyweb1966-web

HOBBYOP

8 days ago