A few things to check that commonly cause this to “not work”: 1) Use the correct step path - The callable lives at

prefect.deployments.steps.utility.run_shell_script

, not

prefect.deployments.steps.run_shell_script

. 2) Make sure you’re referencing the right step output -

{{ clone_step.directory }}

only works if your clone step has

id: clone_step

and returns a

directory

field (e.g.,

git_clone

does). 3) Quote templated strings in YAML - Wrap the

script

value in quotes when you include

{{ ... }}

to avoid YAML parsing issues. 4) Run the step in the right phase - If you need to install on the machine that will run your flow (e.g., your worker host with

/home/ubuntu/prefect-venv

), put this in the

pull:

section. Steps under

build:

run where you call

prefect deploy

(often your local machine or CI), not on the worker. Recommended approach (built-in step for requirements):

pull:
  - prefect.deployments.steps.pull.git_clone:
      id: clone_step
      repository: <https://github.com/owner/repo.git>
      branch: main

  - prefect.deployments.steps.utility.pip_install_requirements:
      directory: "{{ clone_step.directory }}"
      requirements_file: requirements.txt
      stream_output: true

If you really want to call a specific pip path:

pull:
  - prefect.deployments.steps.pull.git_clone:
      id: clone_step
      repository: <https://github.com/owner/repo.git>
      branch: main

  - prefect.deployments.steps.utility.run_shell_script:
      directory: "{{ clone_step.directory }}"
      script: "/home/ubuntu/prefect-venv/bin/pip install -r requirements.txt"
      stream_output: true

Or, keeping your original style but fixing the path and quoting:

- prefect.deployments.steps.pull.git_clone:
    id: clone_step
    repository: <https://github.com/owner/repo.git>

- prefect.deployments.steps.utility.run_shell_script:
    script: "/home/ubuntu/prefect-venv/bin/pip install -r {{ clone_step.directory }}/requirements.txt"
    stream_output: true

Docs for reference: - Steps utility (run_shell_script, pip_install_requirements) - prefect.yaml guide If it’s still failing, could you share: - Which section you placed the step in (

build

,

push

, or

pull

)? - The exact error output from the failed step? - How your clone step is defined (to confirm its

id

and output)?