Revert "Remove a bit of sys.path hackery."

This reverts commit 77630a16be82c17cf2d9d190e3c8821cb2d52aaf.

Reason for revert: Seems to be impacting infra builders e.g.

Original change's description:
> Remove a bit of sys.path hackery.
> Previously would reconfigure sys.path during the execution of
> the recipe code in order to make `from recipe_engine import ...` work.
> This changes it so that all known executions of (namely
> and the two bundled launcher scripts) just set PYTHONPATH
> correctly prior to invoking
> R=fancl, yiwzhang
> Bug: 1462728
> Change-Id: Ice5a9351a81dcdd46db59afb42f6a5b85049cfa3
> Reviewed-on:
> Reviewed-by: Yiwei Zhang <>
> Commit-Queue: Robbie Iannucci <>

Bug: 1462728
Change-Id: I7926d1e7e064ff5a8e1a56603e5cf1365393c3b4
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Commit-Queue: Rubber Stamper <>
Bot-Commit: Rubber Stamper <>
Auto-Submit: Robbie Iannucci <>
1 file changed
tree: e6cb2ba01b1e7050d80b2df54fc97d0eca7b8abe
  1. doc/
  2. infra/
  3. misc/
  4. recipe_engine/
  5. recipe_modules/
  6. recipe_proto/
  7. recipes/
  8. unittests/
  9. .editorconfig
  10. .gitattributes
  11. .gitignore
  12. .pycharm.vpython3
  13. .style.yapf
  14. .vpython3
  15. .vscode.vpython3
  17. codereview.settings
  20. OWNERS
  22. pyproject.toml
  25. recipe.warnings


Recipes are a domain-specific language (embedded in Python) for specifying sequences of subprocess calls in a cross-platform and testable way.

They allow writing build flows which integrate with the rest of LUCI.

Documentation for the recipe engine (including this file!). Take a look at the user guide for some hints on how to get started. See the implementation details doc for more detailed implementation information about the recipe engine.


  • Sign the Google CLA.
  • Make sure your and are configured in git config.

Run the following to setup the code review tool and create your first review:

# Get `depot_tools` in $PATH if you don't have it
git clone $HOME/src/depot_tools
export PATH="$PATH:$HOME/src/depot_tools"

# Check out the recipe engine repo
git clone $HOME/src/recipes-py

# make your change
cd $HOME/src/recipes-py
git new-branch cool_feature
# hack hack
git commit -a -m "This is awesome"

# This will ask for your Google Account credentials.
git cl upload -s -r
# Wait for approval over email.
# Click "Submit to CQ" button or ask reviewer to do it for you.
# Wait for the change to be tested and landed automatically.

Use git cl help and git cl help <cmd> for more details.