rules_python provides a REPL to help with debugging and developing. The goal of the REPL is to present an environment identical to what a {bzl:obj}py_binary creates for your code.
Start the REPL with the following command:
$ bazel run @rules_python//python/bin:repl Python 3.11.11 (main, Mar 17 2025, 21:02:09) [Clang 20.1.0 ] on linux Type "help", "copyright", "credits" or "license" for more information. >>>
Settings like //python/config_settings:python_version will influence the exact behaviour.
$ bazel run @rules_python//python/bin:repl --@rules_python//python/config_settings:python_version=3.13 Python 3.13.2 (main, Mar 17 2025, 21:02:54) [Clang 20.1.0 ] on linux Type "help", "copyright", "credits" or "license" for more information. >>>
See //python/config_settings and Environment Variables for more settings.
The //python/bin:repl_dep command line flag gives the REPL access to a target that provides the {bzl:obj}PyInfo provider.
$ bazel run @rules_python//python/bin:repl --@rules_python//python/bin:repl_dep=@rules_python//tools:wheelmaker Python 3.11.11 (main, Mar 17 2025, 21:02:09) [Clang 20.1.0 ] on linux Type "help", "copyright", "credits" or "license" for more information. >>> import tools.wheelmaker >>>
By default, the //python/bin:repl target will invoke the shell from the code module. It's possible to switch to another shell by writing a custom “stub” and pointing the target at the necessary dependencies.
For an IPython shell, create a file as follows.
import IPython IPython.start_ipython()
Assuming the file is called ipython_stub.py and the pip.parse hub's name is my_deps, set this up in the .bazelrc file:
# Allow the REPL stub to import ipython. In this case, @my_deps is the hub name # of the pip.parse() call. build --@rules_python//python/bin:repl_stub_dep=@my_deps//ipython # Point the REPL at the stub created above. build --@rules_python//python/bin:repl_stub=//path/to:ipython_stub.py