diff --git a/experimental/rules_python_external/.bazelignore b/experimental/rules_python_external/.bazelignore
new file mode 100644
index 0000000000..90c978b36e
--- /dev/null
+++ b/experimental/rules_python_external/.bazelignore
@@ -0,0 +1 @@
+example/
diff --git a/experimental/rules_python_external/.bazelrc b/experimental/rules_python_external/.bazelrc
new file mode 100644
index 0000000000..fa4bb2e33f
--- /dev/null
+++ b/experimental/rules_python_external/.bazelrc
@@ -0,0 +1,2 @@
+build --aspects @mypy_integration//:mypy.bzl%mypy_aspect
+build --output_groups=+mypy
diff --git a/experimental/rules_python_external/.gitattributes b/experimental/rules_python_external/.gitattributes
new file mode 100644
index 0000000000..0bad51cbd1
--- /dev/null
+++ b/experimental/rules_python_external/.gitattributes
@@ -0,0 +1 @@
+example/* linguist-vendored
diff --git a/experimental/rules_python_external/.github/workflows/continuous-integration.yml b/experimental/rules_python_external/.github/workflows/continuous-integration.yml
new file mode 100644
index 0000000000..01c4cdba23
--- /dev/null
+++ b/experimental/rules_python_external/.github/workflows/continuous-integration.yml
@@ -0,0 +1,24 @@
+name: CI
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+    # Checks-out the repository under $GITHUB_WORKSPACE, so the job can access it
+    - uses: actions/checkout@v2
+
+    - name: Setup Bazel
+      uses: abhinavsingh/setup-bazel@v3
+      with:
+        # Bazel version to install e.g. 1.2.1, 2.0.0, ...
+        version: 2.0.0 # optional, default is 2.0.0
+
+    - name: Run tests
+      run: bazel test //...
diff --git a/experimental/rules_python_external/.gitignore b/experimental/rules_python_external/.gitignore
new file mode 100644
index 0000000000..74570cb0c1
--- /dev/null
+++ b/experimental/rules_python_external/.gitignore
@@ -0,0 +1,135 @@
+# Intellij
+.ijwb/
+.idea/
+
+# Bazel
+bazel-*
+
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+pip-wheel-metadata/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.nox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+*.py,cover
+.hypothesis/
+.pytest_cache/
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+db.sqlite3-journal
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# IPython
+profile_default/
+ipython_config.py
+
+# pyenv
+.python-version
+
+# pipenv
+#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
+#   However, in case of collaboration, if having platform-specific dependencies or dependencies
+#   having no cross-platform support, pipenv may install dependencies that don't work, or not
+#   install all needed dependencies.
+#Pipfile.lock
+
+# PEP 582; used by e.g. github.com/David-OConnor/pyflow
+__pypackages__/
+
+# Celery stuff
+celerybeat-schedule
+celerybeat.pid
+
+# SageMath parsed files
+*.sage.py
+
+# Environments
+.env
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+.dmypy.json
+dmypy.json
+
+# Pyre type checker
+.pyre/
diff --git a/experimental/rules_python_external/BUILD b/experimental/rules_python_external/BUILD
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/experimental/rules_python_external/LICENSE b/experimental/rules_python_external/LICENSE
new file mode 100644
index 0000000000..261eeb9e9f
--- /dev/null
+++ b/experimental/rules_python_external/LICENSE
@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
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+   Licensed under the Apache License, Version 2.0 (the "License");
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+       http://www.apache.org/licenses/LICENSE-2.0
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+   distributed under the License is distributed on an "AS IS" BASIS,
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+   See the License for the specific language governing permissions and
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diff --git a/experimental/rules_python_external/README.md b/experimental/rules_python_external/README.md
new file mode 100644
index 0000000000..c21dda017f
--- /dev/null
+++ b/experimental/rules_python_external/README.md
@@ -0,0 +1,125 @@
+# rules_python_external ![](https://github.com/dillon-giacoppo/rules_python_external/workflows/CI/badge.svg)
+
+Bazel rules to transitively fetch and install Python dependencies from a requirements.txt file.
+
+## Features
+
+The rules address most of the top packaging issues in [`bazelbuild/rules_python`](https://github.com/bazelbuild/rules_python). This means the rules support common packages such
+as [`tensorflow`](https://pypi.org/project/tensorflow/) and [`google.cloud`](https://github.com/googleapis/google-cloud-python) natively.
+
+* Transitive dependency resolution:
+    [#35](https://github.com/bazelbuild/rules_python/issues/35),
+    [#102](https://github.com/bazelbuild/rules_python/issues/102)
+* Minimal runtime dependencies:
+    [#184](https://github.com/bazelbuild/rules_python/issues/184)
+* Support for [spreading purelibs](https://www.python.org/dev/peps/pep-0491/#installing-a-wheel-distribution-1-0-py32-none-any-whl):
+    [#71](https://github.com/bazelbuild/rules_python/issues/71)
+* Support for [namespace packages](https://packaging.python.org/guides/packaging-namespace-packages/):
+    [#14](https://github.com/bazelbuild/rules_python/issues/14),
+    [#55](https://github.com/bazelbuild/rules_python/issues/55),
+    [#65](https://github.com/bazelbuild/rules_python/issues/65),
+    [#93](https://github.com/bazelbuild/rules_python/issues/93),
+    [#189](https://github.com/bazelbuild/rules_python/issues/189)
+* Fetches pip packages only for building Python targets:
+    [#96](https://github.com/bazelbuild/rules_python/issues/96)
+* Reproducible builds:
+    [#154](https://github.com/bazelbuild/rules_python/issues/154),
+    [#176](https://github.com/bazelbuild/rules_python/issues/176)
+
+## Usage
+
+#### Prerequisites
+
+The rules support Python >= 3.5 (the oldest [maintained release](https://devguide.python.org/#status-of-python-branches)).
+
+#### Setup `WORKSPACE`
+
+```python
+rules_python_external_version = "{COMMIT_SHA}"
+
+http_archive(
+    name = "rules_python_external",
+    sha256 = "", # Fill in with correct sha256 of your COMMIT_SHA version
+    strip_prefix = "rules_python_external-{version}".format(version = rules_python_external_version),
+    url = "https://github.com/dillon-giacoppo/rules_python_external/archive/v{version}.zip".format(version = rules_python_external_version),
+)
+
+# Install the rule dependencies
+load("@rules_python_external//:repositories.bzl", "rules_python_external_dependencies")
+rules_python_external_dependencies()
+
+load("@rules_python_external//:defs.bzl", "pip_install")
+pip_install(
+    name = "py_deps",
+    requirements = "//:requirements.txt",
+    # (Optional) You can provide a python interpreter (by path):
+    python_interpreter = "/usr/bin/python3.8",
+    # (Optional) Alternatively you can provide an in-build python interpreter, that is available as a Bazel target.
+    # This overrides `python_interpreter`.
+    # Note: You need to set up the interpreter target beforehand (not shown here). Please see the `example` folder for further details.
+    #python_interpreter_target = "@python_interpreter//:python_bin",
+)
+```
+
+#### Example `BUILD` file.
+
+```python
+load("@py_deps//:requirements.bzl", "requirement")
+
+py_binary(
+    name = "main",
+    srcs = ["main.py"],
+    deps = [
+        requirement("boto3"),
+    ],
+)
+```
+
+Note that above you do not need to add transitively required packages to `deps = [ ... ]`
+
+#### Setup `requirements.txt`
+
+While `rules_python_external` **does not** require a _transitively-closed_ `requirements.txt` file, it is recommended.
+But if you want to just have top-level packages listed, that also will work.
+
+Transitively-closed requirements specs are very tedious to produce and maintain manually. To automate the process we
+recommend [`pip-compile` from `jazzband/pip-tools`](https://github.com/jazzband/pip-tools#example-usage-for-pip-compile).
+
+For example, `pip-compile` takes a `requirements.in` like this:
+
+```
+boto3~=1.9.227
+botocore~=1.12.247
+click~=7.0
+```
+
+`pip-compile` 'compiles' it so you get a transitively-closed `requirements.txt` like this, which should be passed to
+`pip_install` below:
+
+```
+boto3==1.9.253
+botocore==1.12.253
+click==7.0
+docutils==0.15.2          # via botocore
+jmespath==0.9.4           # via boto3, botocore
+python-dateutil==2.8.1    # via botocore
+s3transfer==0.2.1         # via boto3
+six==1.14.0               # via python-dateutil
+urllib3==1.25.8           # via botocore
+```
+
+### Demo
+
+You can find a demo in the [example/](./example) directory.
+
+## Development
+
+### Testing
+
+`bazel test //...`
+
+## Adopters
+
+Here's a (non-exhaustive) list of companies that use `rules_python_external` in production. Don't see yours? [You can add it in a PR](https://github.com/dillon-giacoppo/rules_python_external/edit/master/README.md)!
+
+* [Canva](https://www.canva.com/)
diff --git a/experimental/rules_python_external/WORKSPACE b/experimental/rules_python_external/WORKSPACE
new file mode 100644
index 0000000000..ad38285c72
--- /dev/null
+++ b/experimental/rules_python_external/WORKSPACE
@@ -0,0 +1,43 @@
+workspace(name = "rules_python_external")
+
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+
+http_archive(
+    name = "rules_python",
+    sha256 = "d2865e2ce23ee217aaa408ddaa024ca472114a6f250b46159d27de05530c75e3",
+    strip_prefix = "rules_python-7b222cfdb4e59b9fd2a609e1fbb233e94fdcde7c",
+    url = "https://github.com/bazelbuild/rules_python/archive/7b222cfdb4e59b9fd2a609e1fbb233e94fdcde7c.tar.gz",
+)
+
+load("@rules_python//python:repositories.bzl", "py_repositories")
+py_repositories()
+
+load("//:repositories.bzl", "rules_python_external_dependencies")
+rules_python_external_dependencies()
+
+mypy_integration_version = "0.0.7" # latest @ Feb 10th 2020
+
+http_archive(
+    name = "mypy_integration",
+    sha256 = "bf7ecd386740328f96c343dca095a63b93df7f86f8d3e1e2e6ff46e400880077", # for 0.0.7
+    strip_prefix = "bazel-mypy-integration-{version}".format(version = mypy_integration_version),
+    url = "https://github.com/thundergolfer/bazel-mypy-integration/archive/{version}.zip".format(
+        version = mypy_integration_version
+    ),
+)
+
+load(
+    "@mypy_integration//repositories:repositories.bzl",
+    mypy_integration_repositories = "repositories",
+)
+
+mypy_integration_repositories()
+
+load("@mypy_integration//:config.bzl", "mypy_configuration")
+mypy_configuration("//tools/typing:mypy.ini")
+
+load("@mypy_integration//repositories:deps.bzl", mypy_integration_deps = "deps")
+mypy_integration_deps("//tools/typing:mypy_version.txt")
+
+load("@mypy_integration//repositories:pip_repositories.bzl", "pip_deps")
+pip_deps()
diff --git a/experimental/rules_python_external/defs.bzl b/experimental/rules_python_external/defs.bzl
new file mode 100644
index 0000000000..bbac671a30
--- /dev/null
+++ b/experimental/rules_python_external/defs.bzl
@@ -0,0 +1,108 @@
+load("//:repositories.bzl", "all_requirements")
+
+DEFAULT_REPOSITORY_NAME = "pip"
+
+def _pip_repository_impl(rctx):
+    python_interpreter = rctx.attr.python_interpreter
+    if rctx.attr.python_interpreter_target != None:
+        target = rctx.attr.python_interpreter_target
+        python_interpreter = rctx.path(target)
+    else:
+        if "/" not in python_interpreter:
+            python_interpreter = rctx.which(python_interpreter)
+        if not python_interpreter:
+            fail("python interpreter not found")
+
+    rctx.file("BUILD", "")
+
+    # Get the root directory of these rules
+    rules_root = rctx.path(Label("//:BUILD")).dirname
+    thirdparty_roots = [
+        # Includes all the external dependencies from repositories.bzl
+        rctx.path(Label("@" + repo + "//:BUILD.bazel")).dirname
+        for repo in all_requirements
+    ]
+    separator = ":" if not "windows" in rctx.os.name.lower() else ";"
+    pypath = separator.join([str(p) for p in [rules_root] + thirdparty_roots])
+
+    args = [
+        python_interpreter,
+        "-m",
+        "extract_wheels",
+        "--requirements",
+        rctx.path(rctx.attr.requirements),
+        "--repo",
+        "@%s" % rctx.attr.name,
+    ]
+
+    if rctx.attr.extra_pip_args:
+        args += [
+            "--extra_pip_args",
+            struct(args = rctx.attr.extra_pip_args).to_json(),
+        ]
+
+    if rctx.attr.pip_data_exclude:
+        args += [
+            "--pip_data_exclude",
+            struct(exclude = rctx.attr.pip_data_exclude).to_json(),
+        ]
+
+    if rctx.attr.enable_implicit_namespace_pkgs:
+        args += [
+            "--enable_implicit_namespace_pkgs"
+        ]
+
+    result = rctx.execute(
+        args,
+        environment = {
+            # Manually construct the PYTHONPATH since we cannot use the toolchain here
+            "PYTHONPATH": pypath,
+        },
+        timeout = rctx.attr.timeout,
+        quiet = rctx.attr.quiet,
+    )
+    if result.return_code:
+        fail("rules_python_external failed: %s (%s)" % (result.stdout, result.stderr))
+
+    return
+
+pip_repository = repository_rule(
+    attrs = {
+        "requirements": attr.label(allow_single_file = True, mandatory = True),
+        "wheel_env": attr.string_dict(),
+        "python_interpreter": attr.string(default = "python3"),
+        "python_interpreter_target": attr.label(allow_single_file = True, doc = """
+If you are using a custom python interpreter built by another repository rule,
+use this attribute to specify its BUILD target. This allows pip_repository to invoke
+pip using the same interpreter as your toolchain. If set, takes precedence over
+python_interpreter.
+"""),
+        # 600 is documented as default here: https://docs.bazel.build/versions/master/skylark/lib/repository_ctx.html#execute
+        "timeout": attr.int(default = 600),
+        "quiet": attr.bool(default = True),
+        "extra_pip_args": attr.string_list(
+            doc = "Extra arguments to pass on to pip. Must not contain spaces.",
+        ),
+        "pip_data_exclude": attr.string_list(
+            doc = "Additional data exclusion parameters to add to the pip packages BUILD file.",
+        ),
+        "enable_implicit_namespace_pkgs": attr.bool(
+            default = False,
+            doc = """
+If true, disables conversion of native namespace packages into pkg-util style namespace packages. When set all py_binary
+and py_test targets must specify either `legacy_create_init=False` or the global Bazel option
+`--incompatible_default_to_explicit_init_py` to prevent `__init__.py` being automatically generated in every directory.
+
+This option is required to support some packages which cannot handle the conversion to pkg-util style.
+            """,
+        ),
+    },
+    implementation = _pip_repository_impl,
+)
+
+def pip_install(requirements, name = DEFAULT_REPOSITORY_NAME, **kwargs):
+    pip_repository(
+        name = name,
+        requirements = requirements,
+        **kwargs
+    )
diff --git a/experimental/rules_python_external/example/BUILD b/experimental/rules_python_external/example/BUILD
new file mode 100644
index 0000000000..64a3718ccf
--- /dev/null
+++ b/experimental/rules_python_external/example/BUILD
@@ -0,0 +1,35 @@
+load("@pip//:requirements.bzl", "requirement")
+
+# Toolchain setup, this is optional.
+# Demonstrate that we can use the same python interpreter for the toolchain and executing pip in pip install (see WORKSPACE).
+#
+#load("@rules_python//python:defs.bzl", "py_runtime_pair")
+#
+#py_runtime(
+#    name = "python3_runtime",
+#    files = ["@python_interpreter//:files"],
+#    interpreter = "@python_interpreter//:python_bin",
+#    python_version = "PY3",
+#    visibility = ["//visibility:public"],
+#)
+#
+#py_runtime_pair(
+#    name = "my_py_runtime_pair",
+#    py2_runtime = None,
+#    py3_runtime = ":python3_runtime",
+#)
+#
+#toolchain(
+#    name = "my_py_toolchain",
+#    toolchain = ":my_py_runtime_pair",
+#    toolchain_type = "@bazel_tools//tools/python:toolchain_type",
+#)
+# End of toolchain setup.
+
+py_binary(
+    name = "main",
+    srcs = ["main.py"],
+    deps = [
+        requirement("boto3"),
+    ],
+)
diff --git a/experimental/rules_python_external/example/WORKSPACE b/experimental/rules_python_external/example/WORKSPACE
new file mode 100644
index 0000000000..639308a5fd
--- /dev/null
+++ b/experimental/rules_python_external/example/WORKSPACE
@@ -0,0 +1,90 @@
+workspace(name = "example_repo")
+
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+
+http_archive(
+    name = "rules_python",
+    url = "https://github.com/bazelbuild/rules_python/releases/download/0.0.2/rules_python-0.0.2.tar.gz",
+    strip_prefix = "rules_python-0.0.2",
+    sha256 = "b5668cde8bb6e3515057ef465a35ad712214962f0b3a314e551204266c7be90c",
+)
+
+load("@rules_python//python:repositories.bzl", "py_repositories")
+
+py_repositories()
+
+local_repository(
+    name = "rules_python_external",
+    path = "../",
+)
+
+load("@rules_python_external//:repositories.bzl", "rules_python_external_dependencies")
+
+rules_python_external_dependencies()
+
+load("@rules_python_external//:defs.bzl", "pip_install")
+
+pip_install(
+    # (Optional) You can provide extra parameters to pip.
+    # Here, make pip output verbose (this is usable with `quiet = False`).
+    #extra_pip_args = ["-v"],
+
+    # (Optional) You can exclude custom elements in the data section of the generated BUILD files for pip packages.
+    # Exclude directories with spaces in their names in this example (avoids build errors if there are such directories).
+    #pip_data_exclude = ["**/* */**"],
+
+    # (Optional) You can provide a python_interpreter (path) or a python_interpreter_target (a Bazel target, that
+    # acts as an executable). The latter can be anything that could be used as Python interpreter. E.g.:
+    # 1. Python interpreter that you compile in the build file (as above in @python_interpreter).
+    # 2. Pre-compiled python interpreter included with http_archive
+    # 3. Wrapper script, like in the autodetecting python toolchain.
+    #python_interpreter_target = "@python_interpreter//:python_bin",
+
+    # (Optional) You can set quiet to False if you want to see pip output.
+    #quiet = False,
+
+    # Uses the default repository name "pip"
+    requirements = "//:requirements.txt",
+)
+
+# You could optionally use an in-build, compiled python interpreter as a toolchain,
+# and also use it to execute pip.
+#
+# Special logic for building python interpreter with OpenSSL from homebrew.
+# See https://devguide.python.org/setup/#macos-and-os-x
+#_py_configure = """
+#if [[ "$OSTYPE" == "darwin"* ]]; then
+#    ./configure --prefix=$(pwd)/bazel_install --with-openssl=$(brew --prefix openssl)
+#else
+#    ./configure --prefix=$(pwd)/bazel_install
+#fi
+#"""
+#
+# NOTE: you need to have the SSL headers installed to build with openssl support (and use HTTPS).
+# E.g. on Ubuntu: `sudo apt install libssl-dev`
+#http_archive(
+#    name = "python_interpreter",
+#    build_file_content = """
+#exports_files(["python_bin"])
+#filegroup(
+#    name = "files",
+#    srcs = glob(["bazel_install/**"], exclude = ["**/* *"]),
+#    visibility = ["//visibility:public"],
+#)
+#""",
+#    patch_cmds = [
+#        "mkdir $(pwd)/bazel_install",
+#        _py_configure,
+#        "make",
+#        "make install",
+#        "ln -s bazel_install/bin/python3 python_bin",
+#    ],
+#    sha256 = "dfab5ec723c218082fe3d5d7ae17ecbdebffa9a1aea4d64aa3a2ecdd2e795864",
+#    strip_prefix = "Python-3.8.3",
+#    urls = ["https://www.python.org/ftp/python/3.8.3/Python-3.8.3.tar.xz"],
+#)
+
+# Optional:
+# Register the toolchain with the same python interpreter we used for pip in pip_install().
+#register_toolchains("//:my_py_toolchain")
+# End of in-build Python interpreter setup.
diff --git a/experimental/rules_python_external/example/main.py b/experimental/rules_python_external/example/main.py
new file mode 100644
index 0000000000..e5c690b621
--- /dev/null
+++ b/experimental/rules_python_external/example/main.py
@@ -0,0 +1,4 @@
+import boto3
+
+if __name__ == "__main__":
+    pass
diff --git a/experimental/rules_python_external/example/requirements.txt b/experimental/rules_python_external/example/requirements.txt
new file mode 100644
index 0000000000..30ddf823b8
--- /dev/null
+++ b/experimental/rules_python_external/example/requirements.txt
@@ -0,0 +1 @@
+boto3
diff --git a/experimental/rules_python_external/extract_wheels/BUILD b/experimental/rules_python_external/extract_wheels/BUILD
new file mode 100644
index 0000000000..afd2f45ce3
--- /dev/null
+++ b/experimental/rules_python_external/extract_wheels/BUILD
@@ -0,0 +1,8 @@
+load("//:repositories.bzl", "all_requirements")
+
+py_binary(
+    name = "extract_wheels",
+    srcs = ["__init__.py", "__main__.py"],
+    main = "__main__.py",
+    deps = ["//extract_wheels/lib"],
+)
diff --git a/experimental/rules_python_external/extract_wheels/__init__.py b/experimental/rules_python_external/extract_wheels/__init__.py
new file mode 100644
index 0000000000..8184dac6aa
--- /dev/null
+++ b/experimental/rules_python_external/extract_wheels/__init__.py
@@ -0,0 +1,110 @@
+"""extract_wheels
+
+extract_wheels resolves and fetches artifacts transitively from the Python Package Index (PyPI) based on a
+requirements.txt. It generates the required BUILD files to consume these packages as Python libraries.
+
+Under the hood, it depends on the `pip wheel` command to do resolution, download, and compilation into wheels.
+"""
+import argparse
+import glob
+import os
+import subprocess
+import sys
+import json
+
+from extract_wheels.lib import bazel, requirements
+
+
+def configure_reproducible_wheels() -> None:
+    """Modifies the environment to make wheel building reproducible.
+
+    Wheels created from sdists are not reproducible by default. We can however workaround this by
+    patching in some configuration with environment variables.
+    """
+
+    # wheel, by default, enables debug symbols in GCC. This incidentally captures the build path in the .so file
+    # We can override this behavior by disabling debug symbols entirely.
+    # https://github.com/pypa/pip/issues/6505
+    if "CFLAGS" in os.environ:
+        os.environ["CFLAGS"] += " -g0"
+    else:
+        os.environ["CFLAGS"] = "-g0"
+
+    # set SOURCE_DATE_EPOCH to 1980 so that we can use python wheels
+    # https://github.com/NixOS/nixpkgs/blob/master/doc/languages-frameworks/python.section.md#python-setuppy-bdist_wheel-cannot-create-whl
+    if "SOURCE_DATE_EPOCH" not in os.environ:
+        os.environ["SOURCE_DATE_EPOCH"] = "315532800"
+
+    # Python wheel metadata files can be unstable.
+    # See https://bitbucket.org/pypa/wheel/pull-requests/74/make-the-output-of-metadata-files/diff
+    if "PYTHONHASHSEED" not in os.environ:
+        os.environ["PYTHONHASHSEED"] = "0"
+
+
+def main() -> None:
+    """Main program.
+
+    Exits zero on successful program termination, non-zero otherwise.
+    """
+
+    configure_reproducible_wheels()
+
+    parser = argparse.ArgumentParser(
+        description="Resolve and fetch artifacts transitively from PyPI"
+    )
+    parser.add_argument(
+        "--requirements",
+        action="store",
+        required=True,
+        help="Path to requirements.txt from where to install dependencies",
+    )
+    parser.add_argument(
+        "--repo",
+        action="store",
+        required=True,
+        help="The external repo name to install dependencies. In the format '@{REPO_NAME}'",
+    )
+    parser.add_argument(
+        "--extra_pip_args", action="store", help="Extra arguments to pass down to pip.",
+    )
+    parser.add_argument(
+        "--pip_data_exclude",
+        action="store",
+        help="Additional data exclusion parameters to add to the pip packages BUILD file.",
+    )
+    parser.add_argument(
+        "--enable_implicit_namespace_pkgs",
+        action="store_true",
+        help="Disables conversion of implicit namespace packages into pkg-util style packages.",
+    )
+    args = parser.parse_args()
+
+    pip_args = [sys.executable, "-m", "pip", "wheel", "-r", args.requirements]
+    if args.extra_pip_args:
+        pip_args += json.loads(args.extra_pip_args)["args"]
+
+    # Assumes any errors are logged by pip so do nothing. This command will fail if pip fails
+    subprocess.run(pip_args, check=True)
+
+    extras = requirements.parse_extras(args.requirements)
+
+    if args.pip_data_exclude:
+        pip_data_exclude = json.loads(args.pip_data_exclude)["exclude"]
+    else:
+        pip_data_exclude = []
+
+    targets = [
+        '"%s%s"'
+        % (
+            args.repo,
+            bazel.extract_wheel(
+                whl, extras, pip_data_exclude, args.enable_implicit_namespace_pkgs
+            ),
+        )
+        for whl in glob.glob("*.whl")
+    ]
+
+    with open("requirements.bzl", "w") as requirement_file:
+        requirement_file.write(
+            bazel.generate_requirements_file_contents(args.repo, targets)
+        )
diff --git a/experimental/rules_python_external/extract_wheels/__main__.py b/experimental/rules_python_external/extract_wheels/__main__.py
new file mode 100644
index 0000000000..939e8b98c1
--- /dev/null
+++ b/experimental/rules_python_external/extract_wheels/__main__.py
@@ -0,0 +1,5 @@
+"""Main entry point."""
+import extract_wheels
+
+if __name__ == "__main__":
+    extract_wheels.main()
diff --git a/experimental/rules_python_external/extract_wheels/lib/BUILD b/experimental/rules_python_external/extract_wheels/lib/BUILD
new file mode 100644
index 0000000000..ef6e0ab3e4
--- /dev/null
+++ b/experimental/rules_python_external/extract_wheels/lib/BUILD
@@ -0,0 +1,41 @@
+load("//:repositories.bzl", "requirement")
+
+py_library(
+    name = "lib",
+    visibility = ["//extract_wheels:__subpackages__"],
+    srcs = [
+        "bazel.py",
+        "namespace_pkgs.py",
+        "purelib.py",
+        "requirements.py",
+        "wheel.py",
+    ],
+    deps = [
+        requirement("pkginfo"),
+        requirement("setuptools"),
+    ],
+)
+
+py_test(
+    name = "namespace_pkgs_test",
+    size = "small",
+    srcs = [
+        "namespace_pkgs_test.py",
+    ],
+    tags = ["unit"],
+    deps = [
+        ":lib",
+    ],
+)
+
+py_test(
+    name = "requirements_test",
+    size = "small",
+    srcs = [
+        "requirements_test.py",
+    ],
+    tags = ["unit"],
+    deps = [
+        ":lib",
+    ],
+)
diff --git a/experimental/rules_python_external/extract_wheels/lib/__init__.py b/experimental/rules_python_external/extract_wheels/lib/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/experimental/rules_python_external/extract_wheels/lib/bazel.py b/experimental/rules_python_external/extract_wheels/lib/bazel.py
new file mode 100644
index 0000000000..acda4c29fa
--- /dev/null
+++ b/experimental/rules_python_external/extract_wheels/lib/bazel.py
@@ -0,0 +1,166 @@
+"""Utility functions to manipulate Bazel files"""
+import os
+import textwrap
+import json
+from typing import Iterable, List, Dict, Set
+
+from extract_wheels.lib import namespace_pkgs, wheel, purelib
+
+
+def generate_build_file_contents(
+    name: str, dependencies: List[str], pip_data_exclude: List[str]
+) -> str:
+    """Generate a BUILD file for an unzipped Wheel
+
+    Args:
+        name: the target name of the py_library
+        dependencies: a list of Bazel labels pointing to dependencies of the library
+
+    Returns:
+        A complete BUILD file as a string
+
+    We allow for empty Python sources as for Wheels containing only compiled C code
+    there may be no Python sources whatsoever (e.g. packages written in Cython: like `pymssql`).
+    """
+
+    data_exclude = ["**/*.py", "**/* *", "BUILD", "WORKSPACE"] + pip_data_exclude
+
+    return textwrap.dedent(
+        """\
+        package(default_visibility = ["//visibility:public"])
+
+        load("@rules_python//python:defs.bzl", "py_library")
+
+        py_library(
+            name = "{name}",
+            srcs = glob(["**/*.py"], allow_empty = True),
+            data = glob(["**/*"], exclude={data_exclude}),
+            # This makes this directory a top-level in the python import
+            # search path for anything that depends on this.
+            imports = ["."],
+            deps = [{dependencies}],
+        )
+        """.format(
+            name=name,
+            dependencies=",".join(dependencies),
+            data_exclude=json.dumps(data_exclude),
+        )
+    )
+
+
+def generate_requirements_file_contents(repo_name: str, targets: Iterable[str]) -> str:
+    """Generate a requirements.bzl file for a given pip repository
+
+    The file allows converting the PyPI name to a bazel label. Additionally, it adds a function which can glob all the
+    installed dependencies. This is provided for legacy reasons and can be considered deprecated.
+
+    Args:
+        repo_name: the name of the pip repository
+        targets: a list of Bazel labels pointing to all the generated targets
+
+    Returns:
+        A complete requirements.bzl file as a string
+    """
+
+    return textwrap.dedent(
+        """\
+        # Deprecated. This will be removed in a future release
+        all_requirements = [{requirement_labels}]
+
+        def requirement(name):
+           name_key = name.replace("-", "_").replace(".", "_").lower()
+           return "{repo}//pypi__" + name_key
+        """.format(
+            repo=repo_name, requirement_labels=",".join(sorted(targets))
+        )
+    )
+
+
+def sanitise_name(name: str) -> str:
+    """Sanitises the name to be compatible with Bazel labels.
+
+    There are certain requirements around Bazel labels that we need to consider. From the Bazel docs:
+
+        Package names must be composed entirely of characters drawn from the set A-Z, a–z, 0–9, '/', '-', '.', and '_',
+        and cannot start with a slash.
+
+    Due to restrictions on Bazel labels we also cannot allow hyphens. See
+    https://github.com/bazelbuild/bazel/issues/6841
+
+    Further, rules-python automatically adds the repository root to the PYTHONPATH, meaning a package that has the same
+    name as a module is picked up. We workaround this by prefixing with `pypi__`. Alternatively we could require
+    `--noexperimental_python_import_all_repositories` be set, however this breaks rules_docker.
+    See: https://github.com/bazelbuild/bazel/issues/2636
+    """
+
+    return "pypi__" + name.replace("-", "_").replace(".", "_").lower()
+
+
+def setup_namespace_pkg_compatibility(wheel_dir: str) -> None:
+    """Converts native namespace packages to pkgutil-style packages
+
+    Namespace packages can be created in one of three ways. They are detailed here:
+    https://packaging.python.org/guides/packaging-namespace-packages/#creating-a-namespace-package
+
+    'pkgutil-style namespace packages' (2) and 'pkg_resources-style namespace packages' (3) works in Bazel, but
+    'native namespace packages' (1) do not.
+
+    We ensure compatibility with Bazel of method 1 by converting them into method 2.
+
+    Args:
+        wheel_dir: the directory of the wheel to convert
+    """
+
+    namespace_pkg_dirs = namespace_pkgs.implicit_namespace_packages(
+        wheel_dir, ignored_dirnames=["%s/bin" % wheel_dir,],
+    )
+
+    for ns_pkg_dir in namespace_pkg_dirs:
+        namespace_pkgs.add_pkgutil_style_namespace_pkg_init(ns_pkg_dir)
+
+
+def extract_wheel(
+    wheel_file: str,
+    extras: Dict[str, Set[str]],
+    pip_data_exclude: List[str],
+    enable_implicit_namespace_pkgs: bool,
+) -> str:
+    """Extracts wheel into given directory and creates a py_library target.
+
+    Args:
+        wheel_file: the filepath of the .whl
+        extras: a list of extras to add as dependencies for the installed wheel
+        pip_data_exclude: list of file patterns to exclude from the generated data section of the py_library
+        enable_implicit_namespace_pkgs: if true, disables conversion of implicit namespace packages and will unzip as-is
+
+    Returns:
+        The Bazel label for the extracted wheel, in the form '//path/to/wheel'.
+    """
+
+    whl = wheel.Wheel(wheel_file)
+    directory = sanitise_name(whl.name)
+
+    os.mkdir(directory)
+    whl.unzip(directory)
+
+    # Note: Order of operations matters here
+    purelib.spread_purelib_into_root(directory)
+
+    if not enable_implicit_namespace_pkgs:
+        setup_namespace_pkg_compatibility(directory)
+
+    extras_requested = extras[whl.name] if whl.name in extras else set()
+
+    sanitised_dependencies = [
+        '"//%s"' % sanitise_name(d) for d in sorted(whl.dependencies(extras_requested))
+    ]
+
+    with open(os.path.join(directory, "BUILD"), "w") as build_file:
+        contents = generate_build_file_contents(
+            sanitise_name(whl.name), sanitised_dependencies, pip_data_exclude,
+        )
+        build_file.write(contents)
+
+    os.remove(whl.path)
+
+    return "//%s" % directory
diff --git a/experimental/rules_python_external/extract_wheels/lib/namespace_pkgs.py b/experimental/rules_python_external/extract_wheels/lib/namespace_pkgs.py
new file mode 100644
index 0000000000..cb9e164b85
--- /dev/null
+++ b/experimental/rules_python_external/extract_wheels/lib/namespace_pkgs.py
@@ -0,0 +1,72 @@
+"""Utility functions to discover python package types"""
+import os
+import textwrap
+from typing import Set, List, Optional
+
+from extract_wheels.lib import wheel
+
+
+def implicit_namespace_packages(
+    directory: str, ignored_dirnames: Optional[List[str]] = None
+) -> Set[str]:
+    """Discovers namespace packages implemented using the 'native namespace packages' method.
+
+    AKA 'implicit namespace packages', which has been supported since Python 3.3.
+    See: https://packaging.python.org/guides/packaging-namespace-packages/#native-namespace-packages
+
+    Args:
+        directory: The root directory to recursively find packages in.
+        ignored_dirnames: A list of directories to exclude from the search
+
+    Returns:
+        The set of directories found under root to be packages using the native namespace method.
+    """
+    namespace_pkg_dirs = set()
+    for dirpath, dirnames, filenames in os.walk(directory, topdown=True):
+        # We are only interested in dirs with no __init__.py file
+        if "__init__.py" in filenames:
+            dirnames[:] = []  # Remove dirnames from search
+            continue
+
+        for ignored_dir in ignored_dirnames or []:
+            if ignored_dir in dirnames:
+                dirnames.remove(ignored_dir)
+
+        non_empty_directory = dirnames or filenames
+        if (
+            non_empty_directory
+            and
+            # The root of the directory should never be an implicit namespace
+            dirpath != directory
+        ):
+            namespace_pkg_dirs.add(dirpath)
+
+    return namespace_pkg_dirs
+
+
+def add_pkgutil_style_namespace_pkg_init(dir_path: str) -> None:
+    """Adds 'pkgutil-style namespace packages' init file to the given directory
+
+    See: https://packaging.python.org/guides/packaging-namespace-packages/#pkgutil-style-namespace-packages
+
+    Args:
+        dir_path: The directory to create an __init__.py for.
+
+    Raises:
+        ValueError: If the directory already contains an __init__.py file
+    """
+    ns_pkg_init_filepath = os.path.join(dir_path, "__init__.py")
+
+    if os.path.isfile(ns_pkg_init_filepath):
+        raise ValueError("%s already contains an __init__.py file." % dir_path)
+
+    with open(ns_pkg_init_filepath, "w") as ns_pkg_init_f:
+        # See https://packaging.python.org/guides/packaging-namespace-packages/#pkgutil-style-namespace-packages
+        ns_pkg_init_f.write(
+            textwrap.dedent(
+                """\
+                # __path__ manipulation added by rules_python_external to support namespace pkgs.
+                __path__ = __import__('pkgutil').extend_path(__path__, __name__)
+                """
+            )
+        )
diff --git a/experimental/rules_python_external/extract_wheels/lib/namespace_pkgs_test.py b/experimental/rules_python_external/extract_wheels/lib/namespace_pkgs_test.py
new file mode 100644
index 0000000000..899f7bc053
--- /dev/null
+++ b/experimental/rules_python_external/extract_wheels/lib/namespace_pkgs_test.py
@@ -0,0 +1,73 @@
+import pathlib
+import shutil
+import tempfile
+from typing import Optional
+import unittest
+
+from extract_wheels.lib import namespace_pkgs
+
+
+class TempDir:
+    def __init__(self) -> None:
+        self.dir = tempfile.mkdtemp()
+
+    def root(self) -> str:
+        return self.dir
+
+    def add_dir(self, rel_path: str) -> None:
+        d = pathlib.Path(self.dir, rel_path)
+        d.mkdir(parents=True)
+
+    def add_file(self, rel_path: str, contents: Optional[str] = None) -> None:
+        f = pathlib.Path(self.dir, rel_path)
+        f.parent.mkdir(parents=True, exist_ok=True)
+        if contents:
+            with open(str(f), "w") as writeable_f:
+                writeable_f.write(contents)
+        else:
+            f.touch()
+
+    def remove(self) -> None:
+        shutil.rmtree(self.dir)
+
+
+class TestImplicitNamespacePackages(unittest.TestCase):
+    def test_finds_correct_namespace_packages(self) -> None:
+        directory = TempDir()
+        directory.add_file("foo/bar/biz.py")
+        directory.add_file("foo/bee/boo.py")
+        directory.add_file("foo/buu/__init__.py")
+        directory.add_file("foo/buu/bii.py")
+
+        expected = {
+            directory.root() + "/foo",
+            directory.root() + "/foo/bar",
+            directory.root() + "/foo/bee",
+        }
+        actual = namespace_pkgs.implicit_namespace_packages(directory.root())
+        self.assertEqual(actual, expected)
+
+    def test_ignores_empty_directories(self) -> None:
+        directory = TempDir()
+        directory.add_file("foo/bar/biz.py")
+        directory.add_dir("foo/cat")
+
+        expected = {
+            directory.root() + "/foo",
+            directory.root() + "/foo/bar",
+        }
+        actual = namespace_pkgs.implicit_namespace_packages(directory.root())
+        self.assertEqual(actual, expected)
+
+    def test_empty_case(self) -> None:
+        directory = TempDir()
+        directory.add_file("foo/__init__.py")
+        directory.add_file("foo/bar/__init__.py")
+        directory.add_file("foo/bar/biz.py")
+
+        actual = namespace_pkgs.implicit_namespace_packages(directory.root())
+        self.assertEqual(actual, set())
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/experimental/rules_python_external/extract_wheels/lib/purelib.py b/experimental/rules_python_external/extract_wheels/lib/purelib.py
new file mode 100644
index 0000000000..ffcda8ffcc
--- /dev/null
+++ b/experimental/rules_python_external/extract_wheels/lib/purelib.py
@@ -0,0 +1,56 @@
+"""Functions to make purelibs Bazel compatible"""
+import pathlib
+import shutil
+
+from extract_wheels.lib import wheel
+
+
+def spread_purelib_into_root(wheel_dir: str) -> None:
+    """Unpacks purelib directories into the root.
+
+    Args:
+         wheel_dir: The root of the extracted wheel directory.
+    """
+    dist_info = wheel.get_dist_info(wheel_dir)
+    wheel_metadata_file_path = pathlib.Path(dist_info, "WHEEL")
+    wheel_metadata_dict = wheel.parse_wheel_meta_file(str(wheel_metadata_file_path))
+
+    if "Root-Is-Purelib" not in wheel_metadata_dict:
+        raise ValueError(
+            "Invalid WHEEL file '%s'. Expected key 'Root-Is-Purelib'."
+            % wheel_metadata_file_path
+        )
+    root_is_purelib = wheel_metadata_dict["Root-Is-Purelib"]
+
+    if root_is_purelib.lower() == "true":
+        # The Python package code is in the root of the Wheel, so no need to 'spread' anything.
+        return
+
+    dot_data_dir = wheel.get_dot_data_directory(wheel_dir)
+    # 'Root-Is-Purelib: false' is no guarantee a .date directory exists with
+    # package code in it. eg. the 'markupsafe' package.
+    if not dot_data_dir:
+        return
+
+    for child in pathlib.Path(dot_data_dir).iterdir():
+        # TODO(Jonathon): Should all other potential folders get ignored? eg. 'platlib'
+        if str(child).endswith("purelib"):
+            _spread_purelib(child, wheel_dir)
+
+
+def _spread_purelib(purelib_dir: pathlib.Path, root_dir: str) -> None:
+    """Recursively moves all sibling directories of the purelib to the root.
+
+    Args:
+        purelib_dir: The directory of the purelib.
+        root_dir: The directory to move files into.
+    """
+    for grandchild in purelib_dir.iterdir():
+        # Some purelib Wheels, like Tensorflow 2.0.0, have directories
+        # split between the root and the purelib directory. In this case
+        # we should leave the purelib 'sibling' alone.
+        # See: https://github.com/dillon-giacoppo/rules_python_external/issues/8
+        if not pathlib.Path(root_dir, grandchild.name).exists():
+            shutil.move(
+                src=str(grandchild), dst=root_dir,
+            )
diff --git a/experimental/rules_python_external/extract_wheels/lib/requirements.py b/experimental/rules_python_external/extract_wheels/lib/requirements.py
new file mode 100644
index 0000000000..e246379bcc
--- /dev/null
+++ b/experimental/rules_python_external/extract_wheels/lib/requirements.py
@@ -0,0 +1,45 @@
+import re
+from typing import Dict, Set, Tuple, Optional
+
+
+def parse_extras(requirements_path: str) -> Dict[str, Set[str]]:
+    """Parse over the requirements.txt file to find extras requested.
+
+    Args:
+        requirements_path: The filepath for the requirements.txt file to parse.
+
+    Returns:
+         A dictionary mapping the requirement name to a set of extras requested.
+    """
+
+    extras_requested = {}
+    with open(requirements_path, "r") as requirements:
+        # Merge all backslash line continuations so we parse each requirement as a single line.
+        for line in requirements.read().replace("\\\n", "").split("\n"):
+            requirement, extras = _parse_requirement_for_extra(line)
+            if requirement and extras:
+                extras_requested[requirement] = extras
+
+    return extras_requested
+
+
+def _parse_requirement_for_extra(
+    requirement: str,
+) -> Tuple[Optional[str], Optional[Set[str]]]:
+    """Given a requirement string, returns the requirement name and set of extras, if extras specified.
+    Else, returns (None, None)
+    """
+
+    # https://www.python.org/dev/peps/pep-0508/#grammar
+    extras_pattern = re.compile(
+        r"^\s*([0-9A-Za-z][0-9A-Za-z_.\-]*)\s*\[\s*([0-9A-Za-z][0-9A-Za-z_.\-]*(?:\s*,\s*[0-9A-Za-z][0-9A-Za-z_.\-]*)*)\s*\]"
+    )
+
+    matches = extras_pattern.match(requirement)
+    if matches:
+        return (
+            matches.group(1),
+            {extra.strip() for extra in matches.group(2).split(",")},
+        )
+
+    return None, None
diff --git a/experimental/rules_python_external/extract_wheels/lib/requirements_test.py b/experimental/rules_python_external/extract_wheels/lib/requirements_test.py
new file mode 100644
index 0000000000..2b96a754a0
--- /dev/null
+++ b/experimental/rules_python_external/extract_wheels/lib/requirements_test.py
@@ -0,0 +1,32 @@
+import unittest
+
+from extract_wheels.lib import requirements
+
+
+class TestRequirementExtrasParsing(unittest.TestCase):
+    def test_parses_requirement_for_extra(self) -> None:
+        cases = [
+            ("name[foo]", ("name", frozenset(["foo"]))),
+            ("name[ Foo123 ]", ("name", frozenset(["Foo123"]))),
+            (" name1[ foo ] ", ("name1", frozenset(["foo"]))),
+            (
+                "name [fred,bar] @ http://foo.com ; python_version=='2.7'",
+                ("name", frozenset(["fred", "bar"])),
+            ),
+            (
+                "name[quux, strange];python_version<'2.7' and platform_version=='2'",
+                ("name", frozenset(["quux", "strange"])),
+            ),
+            ("name; (os_name=='a' or os_name=='b') and os_name=='c'", (None, None),),
+            ("name@http://foo.com", (None, None),),
+        ]
+
+        for case, expected in cases:
+            with self.subTest():
+                self.assertTupleEqual(
+                    requirements._parse_requirement_for_extra(case), expected
+                )
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/experimental/rules_python_external/extract_wheels/lib/wheel.py b/experimental/rules_python_external/extract_wheels/lib/wheel.py
new file mode 100644
index 0000000000..c13f4e8621
--- /dev/null
+++ b/experimental/rules_python_external/extract_wheels/lib/wheel.py
@@ -0,0 +1,147 @@
+"""Utility class to inspect an extracted wheel directory"""
+import glob
+import os
+import stat
+import zipfile
+from typing import Dict, Optional, Set
+
+import pkg_resources
+import pkginfo
+
+
+def current_umask() -> int:
+    """Get the current umask which involves having to set it temporarily."""
+    mask = os.umask(0)
+    os.umask(mask)
+    return mask
+
+
+def set_extracted_file_to_default_mode_plus_executable(path: str) -> None:
+    """
+    Make file present at path have execute for user/group/world
+    (chmod +x) is no-op on windows per python docs
+    """
+    os.chmod(path, (0o777 & ~current_umask() | 0o111))
+
+
+class Wheel:
+    """Representation of the compressed .whl file"""
+
+    def __init__(self, path: str):
+        self._path = path
+
+    @property
+    def path(self) -> str:
+        return self._path
+
+    @property
+    def name(self) -> str:
+        return str(self.metadata.name)
+
+    @property
+    def metadata(self) -> pkginfo.Wheel:
+        return pkginfo.get_metadata(self.path)
+
+    def dependencies(self, extras_requested: Optional[Set[str]] = None) -> Set[str]:
+        dependency_set = set()
+
+        for wheel_req in self.metadata.requires_dist:
+            req = pkg_resources.Requirement(wheel_req)  # type: ignore
+
+            if req.marker is None or any(
+                req.marker.evaluate({"extra": extra})
+                for extra in extras_requested or [""]
+            ):
+                dependency_set.add(req.name)  # type: ignore
+
+        return dependency_set
+
+    def unzip(self, directory: str) -> None:
+        with zipfile.ZipFile(self.path, "r") as whl:
+            whl.extractall(directory)
+            # The following logic is borrowed from Pip:
+            # https://github.com/pypa/pip/blob/cc48c07b64f338ac5e347d90f6cb4efc22ed0d0b/src/pip/_internal/utils/unpacking.py#L240
+            for info in whl.infolist():
+                name = info.filename
+                # Do not attempt to modify directories.
+                if name.endswith("/") or name.endswith("\\"):
+                    continue
+                mode = info.external_attr >> 16
+                # if mode and regular file and any execute permissions for
+                # user/group/world?
+                if mode and stat.S_ISREG(mode) and mode & 0o111:
+                    name = os.path.join(directory, name)
+                    set_extracted_file_to_default_mode_plus_executable(name)
+
+
+def get_dist_info(wheel_dir: str) -> str:
+    """"Returns the relative path to the dist-info directory if it exists.
+
+    Args:
+         wheel_dir: The root of the extracted wheel directory.
+
+    Returns:
+        Relative path to the dist-info directory if it exists, else, None.
+    """
+    dist_info_dirs = glob.glob(os.path.join(wheel_dir, "*.dist-info"))
+    if not dist_info_dirs:
+        raise ValueError(
+            "No *.dist-info directory found. %s is not a valid Wheel." % wheel_dir
+        )
+
+    if len(dist_info_dirs) > 1:
+        raise ValueError(
+            "Found more than 1 *.dist-info directory. %s is not a valid Wheel."
+            % wheel_dir
+        )
+
+    return dist_info_dirs[0]
+
+
+def get_dot_data_directory(wheel_dir: str) -> Optional[str]:
+    """Returns the relative path to the data directory if it exists.
+
+    See: https://www.python.org/dev/peps/pep-0491/#the-data-directory
+
+    Args:
+         wheel_dir: The root of the extracted wheel directory.
+
+    Returns:
+        Relative path to the data directory if it exists, else, None.
+    """
+
+    dot_data_dirs = glob.glob(os.path.join(wheel_dir, "*.data"))
+    if not dot_data_dirs:
+        return None
+
+    if len(dot_data_dirs) > 1:
+        raise ValueError(
+            "Found more than 1 *.data directory. %s is not a valid Wheel." % wheel_dir
+        )
+
+    return dot_data_dirs[0]
+
+
+def parse_wheel_meta_file(wheel_dir: str) -> Dict[str, str]:
+    """Parses the given WHEEL file into a dictionary.
+
+    Args:
+         wheel_dir: The file path of the WHEEL metadata file in dist-info.
+
+    Returns:
+        The WHEEL file mapped into a dictionary.
+    """
+    contents = {}
+    with open(wheel_dir, "r") as wheel_file:
+        for line in wheel_file:
+            cleaned = line.strip()
+            if not cleaned:
+                continue
+            try:
+                key, value = cleaned.split(":", maxsplit=1)
+                contents[key] = value.strip()
+            except ValueError:
+                raise RuntimeError(
+                    "Encounted invalid line in WHEEL file: '%s'" % cleaned
+                )
+    return contents
diff --git a/experimental/rules_python_external/repositories.bzl b/experimental/rules_python_external/repositories.bzl
new file mode 100644
index 0000000000..8fb146607d
--- /dev/null
+++ b/experimental/rules_python_external/repositories.bzl
@@ -0,0 +1,57 @@
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+load("@bazel_tools//tools/build_defs/repo:utils.bzl", "maybe")
+
+_RULE_DEPS = [
+    (
+        "pypi__pip",
+        "https://files.pythonhosted.org/packages/00/b6/9cfa56b4081ad13874b0c6f96af8ce16cfbc1cb06bedf8e9164ce5551ec1/pip-19.3.1-py2.py3-none-any.whl",
+        "6917c65fc3769ecdc61405d3dfd97afdedd75808d200b2838d7d961cebc0c2c7",
+    ),
+    (
+        "pypi__pkginfo",
+        "https://files.pythonhosted.org/packages/e6/d5/451b913307b478c49eb29084916639dc53a88489b993530fed0a66bab8b9/pkginfo-1.5.0.1-py2.py3-none-any.whl",
+        "a6d9e40ca61ad3ebd0b72fbadd4fba16e4c0e4df0428c041e01e06eb6ee71f32",
+    ),
+    (
+        "pypi__setuptools",
+        "https://files.pythonhosted.org/packages/54/28/c45d8b54c1339f9644b87663945e54a8503cfef59cf0f65b3ff5dd17cf64/setuptools-42.0.2-py2.py3-none-any.whl",
+        "c8abd0f3574bc23afd2f6fd2c415ba7d9e097c8a99b845473b0d957ba1e2dac6",
+    ),
+    (
+        "pypi__wheel",
+        "https://files.pythonhosted.org/packages/00/83/b4a77d044e78ad1a45610eb88f745be2fd2c6d658f9798a15e384b7d57c9/wheel-0.33.6-py2.py3-none-any.whl",
+        "f4da1763d3becf2e2cd92a14a7c920f0f00eca30fdde9ea992c836685b9faf28",
+    ),
+]
+
+_GENERIC_WHEEL = """\
+package(default_visibility = ["//visibility:public"])
+
+load("@rules_python//python:defs.bzl", "py_library")
+
+py_library(
+    name = "lib",
+    srcs = glob(["**/*.py"]),
+    data = glob(["**/*"], exclude=["**/*.py", "**/* *", "BUILD", "WORKSPACE"]),
+    # This makes this directory a top-level in the python import
+    # search path for anything that depends on this.
+    imports = ["."],
+)
+"""
+
+# Collate all the repository names so they can be easily consumed
+all_requirements = [name for (name, _, _) in _RULE_DEPS]
+
+def requirement(pkg):
+    return "@pypi__"+ pkg + "//:lib"
+
+def rules_python_external_dependencies():
+    for (name, url, sha256) in _RULE_DEPS:
+        maybe(
+            http_archive,
+            name,
+            url=url,
+            sha256=sha256,
+            type="zip",
+            build_file_content=_GENERIC_WHEEL,
+        )
diff --git a/experimental/rules_python_external/tools/typing/BUILD b/experimental/rules_python_external/tools/typing/BUILD
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/experimental/rules_python_external/tools/typing/mypy.ini b/experimental/rules_python_external/tools/typing/mypy.ini
new file mode 100644
index 0000000000..ed392f2eeb
--- /dev/null
+++ b/experimental/rules_python_external/tools/typing/mypy.ini
@@ -0,0 +1,24 @@
+[mypy]
+# This should be the oldest supported release of Python
+# https://devguide.python.org/#status-of-python-branches
+python_version = 3.5
+
+# Third-Party packages without Stub files
+# https://mypy.readthedocs.io/en/latest/stubs.html
+[mypy-pkginfo.*]
+ignore_missing_imports = True
+
+[mypy-extract_wheels.*]
+check_untyped_defs = True
+disallow_incomplete_defs = True
+disallow_untyped_calls = True
+disallow_untyped_decorators = True
+disallow_untyped_defs = True
+no_implicit_optional = True
+strict_equality = True
+strict_optional = True
+warn_no_return = True
+warn_redundant_casts = True
+warn_return_any = True
+warn_unreachable = True
+warn_unused_ignores = True
diff --git a/experimental/rules_python_external/tools/typing/mypy_version.txt b/experimental/rules_python_external/tools/typing/mypy_version.txt
new file mode 100644
index 0000000000..9e7ef885f9
--- /dev/null
+++ b/experimental/rules_python_external/tools/typing/mypy_version.txt
@@ -0,0 +1 @@
+mypy==0.780