diff --git a/build_env.py b/build_env.py
index 522e90c..b78932a 100644
--- a/build_env.py
+++ b/build_env.py
@@ -166,13 +166,20 @@ def install_site_file(site_packages_path: pathlib.Path, file: EnvFile) -> None:
         site_path.symlink_to(file.path.resolve())
 
 
-def install_files(env_path: pathlib.Path, files: List[EnvFile]) -> None:
+def install_files(env_path: pathlib.Path, files: List[EnvFile], add_pth: bool) -> None:
     site_packages_path = find_site_packages(env_path)
+    pth = site_packages_path / "venv.pth"
+    pths = set()
     for file in files:
         if is_data_file(file):
             install_data_file(env_path, file)
         else:
-            install_site_file(site_packages_path, file)
+            if add_pth:
+                pths.add(file.env_path.parts[0])
+            else:
+                install_site_file(site_packages_path, file)
+    if add_pth:
+        pth.write_text("\n".join(pths), encoding="utf-8")
 
 
 # A copy of importlib_metadata:entry_points that takes a list of search paths.
@@ -266,7 +273,7 @@ def main():
     builder = venv.EnvBuilder(clear=True, symlinks=True, with_pip=True)
     builder.create(str(env_path))
 
-    install_files(env_path, files)
+    install_files(env_path, files, build_env_input.get("add_pth", False))
     generate_console_scripts(env_path)
 
     extra_commands = build_env_input.get("commands")
diff --git a/venv.bzl b/venv.bzl
index 775e3d4..fcd745b 100644
--- a/venv.bzl
+++ b/venv.bzl
@@ -44,6 +44,7 @@ def _py_venv_deps_impl(ctx):
         "workspace": ctx.workspace_name,
         "imports": imports,
         "files": files,
+        "add_pth": ctx.attr.add_pth,
         "commands": ctx.attr.commands,
         "always_link": ctx.attr.always_link,
     }
@@ -58,12 +59,13 @@ _py_venv_deps = rule(
         "data": attr.label_list(),
         "commands": attr.string_list(),
         "always_link": attr.bool(),
+        "add_pth": attr.bool(),
         "output": attr.output(),
     },
     toolchains = [PYTHON_TOOLCHAIN_TYPE],
 )
 
-def py_venv(name, deps = None, data = None, extra_pip_commands = None, always_link = False, venv_location = None, **kwargs):
+def py_venv(name, deps = None, data = None, extra_pip_commands = None, always_link = False, venv_location = None, add_pth = False, **kwargs):
     deps = deps or []
     data = data or []
     extra_pip_commands = extra_pip_commands or []
@@ -78,6 +80,7 @@ def py_venv(name, deps = None, data = None, extra_pip_commands = None, always_li
         commands = extra_pip_commands,
         always_link = always_link,
         output = out_name,
+        add_pth = add_pth,
         **kwargs,
     )