Hey there! We've found the following might help you get unblocked faster:

• 🧵 Python would not build

• 🧵 Railpack build failed to install protoc

• 🧵 Error: dial tcp: lookup postgres.railway.internal on [xxx.xxx.xxx.xxx](xxx.xxx.xxx.xxx):zz: no such host

• 🧵 Railpack build crash because of fontconfig not detected

If you find the answer from one of these, please let us know by solving the thread!

hey your issue is definitely the git+ssh dependencies railway can't access them during build

ti fix this follow this steps:

1. create a GitHub Personal Access Token (Settings → Developer settings → PAT with repo access)

2. add it to Railway as an environment variable: GITHUB_TOKEN

3. in your pyproject.toml, change your private repo deps from:

my-package = { git = "git+ssh://git@github.com/user/repo.git" }

to:

my-package = { git = "https://x-access-token:${GITHUB_TOKEN}@github.com/user/repo.git" }

4. and make sure you have a nixpacks.toml:

[phases.setup]
nixPkgs = ["python310", "poetry"]

[phases.install]
cmds = ["poetry install --no-dev"]

[start]
cmd = "poetry run gunicorn app:app --bind 0.0.0.0:$PORT"

the SSH keys just aren't available in railway's build env, so switching to HTTPS with the token should get you up and running. also double-check that gunicorn is in your main dependencies, not dev-dependencies.

let me know if that doesn't work

Thanks for the pointer! The general idea was good, but some of the details needed adjustment:

1. pyproject.toml doesn't support command-line substitution at all, so including the credentials in the dependencies list does you no good.

2. You need provide the user name who created the token (i.e., not "x-access-token") in the credentials.

So, I truncated the dependency in pyproject.toml to the mere package name, and included a setup_prod.sh script which does the installation of the two private dependencies using HTTPS. At this point, the build seems to run successfully with all packages installed (see attached log).

Unfortunately, I'm still getting the same error during the deploy stage:

/mise/installs/python/3.13.11/bin/python: No module named gunicorn

Also, I'm using Railpack, so your nixpacks.toml isn't applicable in this case. The Railpack version does seem to install Python correctly though, and pipis available as demonstrated in the log. But... there's still that error. This makes me think the version of pip accessible to my script doesn't correspond with the version of Python actually running at launch. Normally, I'd just log on to the machine and run which to double-check things, but I can't find any way to do that here. Any suggestions?

I finally did work out the issue here. First problem was that bash isn't actually the shell being used, so things like if [[ ... ]] and source were failing to execute. When I switched to pure posix-compliant syntax, I found that I couldn't install my virtual environment anywhere outside the /app directory. But, when I installed everything inside the /app/venv directory, and used . (instead of source) to run the activate command, things worked out. I needed to be sure to do so in both the build script (to get the dependencies in the right place), and in the start script (to be sure to use them), but that got me over the hurdle of actually getting the script to run.

For reference, here's the final build script:

    #/usr/bin/env sh

    VENV_DIR="./authmo/venv"
    python -m venv "${VENV_DIR}"
    if [ ! -d "${VENV_DIR}" ]; then
        echo "Failed to create virtual env."
        exit 125
    fi

    . "${VENV_DIR}/bin/activate"
    echo "Using pip: $(which pip)"

    pip install --upgrade pip
    pip install authmo_common@git+https://${GITHUB_USER}:${GITHUB_TOKEN}@github.com/authmo/common
    pip install authmo_sql@git+https://${GITHUB_USER}:${GITHUB_TOKEN}@github.com/authmo/sql
    pip install .

And here's the final startup script:

    #/usr/bin/env sh

    VENV_DIR="./authmo/venv"
    . "${VENV_DIR}/bin/activate"
    echo "Using python: $(which python)"

    SERVICE_NAME="www2-web" python -m gunicorn "authmo_www.web.server:launchApp()"

your replies that I've seen across this and some other threads are sounding suspiciously like AI... in the bounty rules it says that you can't use AI to produce or enhance your bounty answers and doing so will get you banned from participating in them so just be careful

if you're not using AI then I apologize, that's just how it came across to me

Thank you! I'm paying out to $10 bounty to you for the great answer