Hi Railway Team,

I've been trying to deploy a simple Flask app on Railway using Nixpacks, and I’ve hit a frustrating wall. My app keeps crashing on startup with the following error:

vbnet

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ModuleNotFoundError: No module named 'requests'

Here’s what I’ve set up:

Project Structure

• requirements.txt includes:

  nginx

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  flask requests stripe python-dotenv colorama

• start.sh:

  bash

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  #!/bin/bash pip install -r requirements.txt python app.py

• .nixpacks.toml:

  toml

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  [phases.setup] nixPkgs = ["python311", "gcc"] [phases.install] cmds = [ "python3.11 -m venv venv", ". venv/bin/activate", "pip install -r requirements.txt" ] [phases.start] cmd = ". venv/bin/activate && python app.py"

• Procfile:

  makefile

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  web: python app.py

• The Railway service is set to use the Nixpacks builder and Python is selected in the Providers.

The Problem

Despite everything being correctly defined, Railway crashes on every deploy with the same error:
ModuleNotFoundError: No module named 'requests'
This suggests the pip install -r requirements.txt step is being skipped or not properly executed, even though it’s in both start.sh and .nixpacks.toml.

What I’ve Tried

• Setting a custom start command in Railway to run bash start.sh

• Making start.sh executable with git update-index --chmod=+x start.sh

• Adding .nixpacks.toml to explicitly define build phases

• Switching between Procfile and .nixpacks.toml

• Confirmed requests is definitely listed in requirements.txt

Nothing seems to be triggering the install properly.

Any ideas why Railway isn't installing the requests package on build?

Would greatly appreciate help getting this resolved!

Thanks so much,
Alan (aka chidopro)