diff --git a/contrib/packaging/hgpackaging/pyoxidizer.py b/contrib/packaging/hgpackaging/pyoxidizer.py
new file mode 100644
--- /dev/null
+++ b/contrib/packaging/hgpackaging/pyoxidizer.py
@@ -0,0 +1,70 @@
+# pyoxidizer.py - Functionality for packaging using PyOxidizer.
+#
+# Copyright 2019 Gregory Szorc <gregory.szorc@gmail.com>
+#
+# This software may be used and distributed according to the terms of the
+# GNU General Public License version 2 or any later version.
+
+import os
+import pathlib
+import shutil
+import subprocess
+
+
+def build_pyoxidizer(
+    source_dir: pathlib.Path,
+    build_dir: pathlib.Path,
+    pyoxidizer_bin: pathlib.Path = 'pyoxidizer',
+):
+    """Build Mercurial using PyOxidizer.
+
+    The resulting files will be copied to ``build_dir``.
+    """
+
+    config_path = source_dir / 'rust' / 'hgcli'
+    staging_dir = build_dir / 'staging'
+
+    if staging_dir.exists():
+        shutil.rmtree(staging_dir)
+
+    res = subprocess.run(
+        [str(pyoxidizer_bin), 'app-path', '--release', str(config_path)],
+        check=True,
+        capture_output=True,
+    )
+
+    app_path = pathlib.Path(res.stdout.strip())
+
+    subprocess.run(
+        [str(pyoxidizer_bin), 'build', '--release', str(config_path)],
+        check=True,
+    )
+
+    # PyOxidizer's application staging doesn't currently handle resource
+    # files properly. So we need to massage the file layout so things work.
+    staging_dir.mkdir(parents=True)
+
+    # All files in the root directory are fine.
+    for p in os.listdir(app_path):
+        p = app_path / p
+
+        if p.is_file():
+            dest = staging_dir / p.name
+            shutil.copyfile(p, dest)
+
+    # For the lib directory, only copy .py and .pyc files: we'll manage
+    # the resource files ourselves later.
+    for root, dirs, files in os.walk(app_path / 'lib'):
+        dirs.sort()
+
+        rel_dir = (app_path / 'lib').relative_to(app_path)
+
+        for f in sorted(files):
+            if not f.endswith(('.py', '.pyc')):
+                continue
+
+            dest_dir = staging_dir / rel_dir
+            dest_dir.mkdir(parents=True, exist_ok=True)
+
+            dest = dest_dir / f
+            shutil.copyfile(root / f, dest)
diff --git a/rust/hgcli/Cargo.lock b/rust/hgcli/Cargo.lock
new file mode 100644
--- /dev/null
+++ b/rust/hgcli/Cargo.lock
@@ -0,0 +1,336 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+[[package]]
+name = "aho-corasick"
+version = "0.7.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "autocfg"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "bitflags"
+version = "1.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "byteorder"
+version = "1.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "cc"
+version = "1.0.46"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "cfg-if"
+version = "0.1.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "cloudabi"
+version = "0.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "cpython"
+version = "0.2.1"
+source = "git+https://github.com/indygreg/PyOxidizer.git?tag=v0.3.0#ae305ea8f3aecb6ce558cb0118fd83a4e20c1e81"
+dependencies = [
+ "libc 0.2.65 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-traits 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "python3-sys 0.2.1 (git+https://github.com/indygreg/PyOxidizer.git?tag=v0.3.0)",
+]
+
+[[package]]
+name = "fs_extra"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "fuchsia-cprng"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "hg"
+version = "0.1.0"
+dependencies = [
+ "jemallocator-global 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pyembed 0.3.0",
+]
+
+[[package]]
+name = "jemalloc-sys"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cc 1.0.46 (registry+https://github.com/rust-lang/crates.io-index)",
+ "fs_extra 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.65 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "jemallocator"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "jemalloc-sys 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.65 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "jemallocator-global"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
+ "jemallocator 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "lazy_static"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "libc"
+version = "0.2.65"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "memchr"
+version = "2.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "num-traits"
+version = "0.2.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "autocfg 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "pyembed"
+version = "0.3.0"
+dependencies = [
+ "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cpython 0.2.1 (git+https://github.com/indygreg/PyOxidizer.git?tag=v0.3.0)",
+ "jemalloc-sys 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.65 (registry+https://github.com/rust-lang/crates.io-index)",
+ "python3-sys 0.2.1 (git+https://github.com/indygreg/PyOxidizer.git?tag=v0.3.0)",
+ "uuid 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "python3-sys"
+version = "0.2.1"
+source = "git+https://github.com/indygreg/PyOxidizer.git?tag=v0.3.0#ae305ea8f3aecb6ce558cb0118fd83a4e20c1e81"
+dependencies = [
+ "libc 0.2.65 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand"
+version = "0.6.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "autocfg 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.65 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_hc 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_isaac 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_jitter 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_os 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_pcg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_xorshift 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "autocfg 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "rand_hc"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_isaac"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_jitter"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "libc 0.2.65 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_os"
+version = "0.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "fuchsia-cprng 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.65 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_pcg"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "autocfg 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_xorshift"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rdrand"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "regex"
+version = "1.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "aho-corasick 0.7.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex-syntax 0.6.12 (registry+https://github.com/rust-lang/crates.io-index)",
+ "thread_local 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.6.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "thread_local"
+version = "0.3.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "uuid"
+version = "0.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "winapi"
+version = "0.3.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "winapi-i686-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi-x86_64-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "winapi-i686-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "winapi-x86_64-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[metadata]
+"checksum aho-corasick 0.7.6 (registry+https://github.com/rust-lang/crates.io-index)" = "58fb5e95d83b38284460a5fda7d6470aa0b8844d283a0b614b8535e880800d2d"
+"checksum autocfg 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "1d49d90015b3c36167a20fe2810c5cd875ad504b39cff3d4eae7977e6b7c1cb2"
+"checksum bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cf1de2fe8c75bc145a2f577add951f8134889b4795d47466a54a5c846d691693"
+"checksum byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "a7c3dd8985a7111efc5c80b44e23ecdd8c007de8ade3b96595387e812b957cf5"
+"checksum cc 1.0.46 (registry+https://github.com/rust-lang/crates.io-index)" = "0213d356d3c4ea2c18c40b037c3be23cd639825c18f25ee670ac7813beeef99c"
+"checksum cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)" = "4785bdd1c96b2a846b2bd7cc02e86b6b3dbf14e7e53446c4f54c92a361040822"
+"checksum cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "ddfc5b9aa5d4507acaf872de71051dfd0e309860e88966e1051e462a077aac4f"
+"checksum cpython 0.2.1 (git+https://github.com/indygreg/PyOxidizer.git?tag=v0.3.0)" = "<none>"
+"checksum fs_extra 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5f2a4a2034423744d2cc7ca2068453168dcdb82c438419e639a26bd87839c674"
+"checksum fuchsia-cprng 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "a06f77d526c1a601b7c4cdd98f54b5eaabffc14d5f2f0296febdc7f357c6d3ba"
+"checksum jemalloc-sys 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "0d3b9f3f5c9b31aa0f5ed3260385ac205db665baa41d49bb8338008ae94ede45"
+"checksum jemallocator 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "43ae63fcfc45e99ab3d1b29a46782ad679e98436c3169d15a167a1108a724b69"
+"checksum jemallocator-global 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "991b61de8365c8b5707cf6cabbff98cfd6eaca9b851948b883efea408c7f581e"
+"checksum lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
+"checksum libc 0.2.65 (registry+https://github.com/rust-lang/crates.io-index)" = "1a31a0627fdf1f6a39ec0dd577e101440b7db22672c0901fe00a9a6fbb5c24e8"
+"checksum memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "88579771288728879b57485cc7d6b07d648c9f0141eb955f8ab7f9d45394468e"
+"checksum num-traits 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "6ba9a427cfca2be13aa6f6403b0b7e7368fe982bfa16fccc450ce74c46cd9b32"
+"checksum python3-sys 0.2.1 (git+https://github.com/indygreg/PyOxidizer.git?tag=v0.3.0)" = "<none>"
+"checksum rand 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)" = "6d71dacdc3c88c1fde3885a3be3fbab9f35724e6ce99467f7d9c5026132184ca"
+"checksum rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "556d3a1ca6600bfcbab7c7c91ccb085ac7fbbcd70e008a98742e7847f4f7bcef"
+"checksum rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6fdeb83b075e8266dcc8762c22776f6877a63111121f5f8c7411e5be7eed4b"
+"checksum rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "9c33a3c44ca05fa6f1807d8e6743f3824e8509beca625669633be0acbdf509dc"
+"checksum rand_hc 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7b40677c7be09ae76218dc623efbf7b18e34bced3f38883af07bb75630a21bc4"
+"checksum rand_isaac 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ded997c9d5f13925be2a6fd7e66bf1872597f759fd9dd93513dd7e92e5a5ee08"
+"checksum rand_jitter 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "1166d5c91dc97b88d1decc3285bb0a99ed84b05cfd0bc2341bdf2d43fc41e39b"
+"checksum rand_os 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "7b75f676a1e053fc562eafbb47838d67c84801e38fc1ba459e8f180deabd5071"
+"checksum rand_pcg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "abf9b09b01790cfe0364f52bf32995ea3c39f4d2dd011eac241d2914146d0b44"
+"checksum rand_xorshift 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cbf7e9e623549b0e21f6e97cf8ecf247c1a8fd2e8a992ae265314300b2455d5c"
+"checksum rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "678054eb77286b51581ba43620cc911abf02758c91f93f479767aed0f90458b2"
+"checksum regex 1.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "dc220bd33bdce8f093101afe22a037b8eb0e5af33592e6a9caafff0d4cb81cbd"
+"checksum regex-syntax 0.6.12 (registry+https://github.com/rust-lang/crates.io-index)" = "11a7e20d1cce64ef2fed88b66d347f88bd9babb82845b2b858f3edbf59a4f716"
+"checksum thread_local 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "c6b53e329000edc2b34dbe8545fd20e55a333362d0a321909685a19bd28c3f1b"
+"checksum uuid 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)" = "90dbc611eb48397705a6b0f6e917da23ae517e4d127123d2cf7674206627d32a"
+"checksum winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)" = "8093091eeb260906a183e6ae1abdba2ef5ef2257a21801128899c3fc699229c6"
+"checksum winapi-i686-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
+"checksum winapi-x86_64-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
diff --git a/rust/hgcli/Cargo.toml b/rust/hgcli/Cargo.toml
new file mode 100644
--- /dev/null
+++ b/rust/hgcli/Cargo.toml
@@ -0,0 +1,14 @@
+[package]
+name = "hg"
+version = "0.1.0"
+authors = ["Gregory Szorc <gregory.szorc@gmail.com>"]
+license = "GPL-2.0"
+edition = "2018"
+
+[dependencies]
+jemallocator-global = { version = "0.3", optional = true }
+pyembed = { path = "../pyembed" }
+
+[features]
+default = []
+jemalloc = ["jemallocator-global", "pyembed/jemalloc"]
diff --git a/rust/hgcli/pyoxidizer.toml b/rust/hgcli/pyoxidizer.toml
new file mode 100644
--- /dev/null
+++ b/rust/hgcli/pyoxidizer.toml
@@ -0,0 +1,75 @@
+# This file controls the PyOxidizer build configuration. See the
+# pyoxidizer crate's documentation for extensive documentation
+# on this file format.
+
+[[build]]
+application_name = "hg"
+build_path = "$ORIGIN/../../build/pyoxidizer"
+
+[[embedded_python_config]]
+raw_allocator = "jemalloc"
+
+# Windows doesn't support jemalloc.
+[[embedded_python_config]]
+build_target = "i686-pc-windows-msvc"
+raw_allocator = "system"
+
+[[embedded_python_config]]
+build_target = "x86_64-pc-windows-msvc"
+raw_allocator = "system"
+
+# Mercurial requires a fully featured Python because extensions may use
+# anything.
+[[packaging_rule]]
+type = "stdlib-extensions-policy"
+policy = "all"
+
+[[packaging_rule]]
+type = "stdlib"
+include_source = true
+
+[[packaging_rule]]
+type = "setup-py-install"
+package_path = "../.."
+extra_global_arguments = ["clean", "--all", "build"]
+
+# Our code doesn't yet work with the in-memory importer. So package
+# relative to the executable for now.
+install_location = "app-relative:lib"
+
+[[embedded_python_config]]
+sys_paths = ["$ORIGIN/lib"]
+
+[[embedded_python_run]]
+mode = "eval"
+code = "import hgdemandimport; hgdemandimport.enable(); import mercurial.dispatch; mercurial.dispatch.run()"
+
+# END OF COMMON USER-ADJUSTED SETTINGS.
+#
+# Everything below this is typically managed by PyOxidizer and doesn't need
+# to be updated by people.
+
+[[python_distribution]]
+build_target = "i686-pc-windows-msvc"
+url = "https://github.com/indygreg/python-build-standalone/releases/download/20191025/cpython-3.7.5-windows-x86-20191025T0549.tar.zst"
+sha256 = "388d37bcffee183bc23f5fec9c263779c59d298d35c9e4445b407d95f94db19c"
+[[python_distribution]]
+build_target = "x86_64-apple-darwin"
+url = "https://github.com/indygreg/python-build-standalone/releases/download/20191025/cpython-3.7.5-macos-20191026T0535.tar.zst"
+sha256 = "e8d0710627c017213d9c5c6496577539a5adceb56d3060e07954ce9bf59f39ae"
+[[python_distribution]]
+build_target = "x86_64-pc-windows-msvc"
+url = "https://github.com/indygreg/python-build-standalone/releases/download/20191025/cpython-3.7.5-windows-amd64-20191025T0540.tar.zst"
+sha256 = "86a3260edabeed314c6f32a931e60dd097fa854b1346561443353e1bc90e3edd"
+[[python_distribution]]
+build_target = "x86_64-unknown-linux-gnu"
+url = "https://github.com/indygreg/python-build-standalone/releases/download/20191025/cpython-3.7.5-linux64-20191025T0506.tar.zst"
+sha256 = "608871543e6d2cb80e958638e31158355c578c114e12c77765ea5fb996a5a2c2"
+[[python_distribution]]
+build_target = "x86_64-unknown-linux-musl"
+url = "https://github.com/indygreg/python-build-standalone/releases/download/20191025/cpython-3.7.5-linux64-musl-20191026T0603.tar.zst"
+sha256 = "9d46c1964e32f77f22fec96c8acb905e8d4ff54594ca9a2660467f974dca3a53"
+
+[[pyoxidizer]]
+version = "0.4.0"
+commit = "b489cfb8c575d26469a0a70b255c70264a06b00a"
diff --git a/rust/hgcli/src/main.rs b/rust/hgcli/src/main.rs
new file mode 100644
--- /dev/null
+++ b/rust/hgcli/src/main.rs
@@ -0,0 +1,37 @@
+// main.rs -- Main routines for `hg` program
+//
+// Copyright 2019 Gregory Szorc <gregory.szorc@gmail.com>
+//
+// This software may be used and distributed according to the terms of the
+// GNU General Public License version 2 or any later version.
+
+use pyembed::{default_python_config, MainPythonInterpreter};
+
+fn main() {
+    // The following code is in a block so the MainPythonInterpreter is destroyed in an
+    // orderly manner, before process exit.
+    let code = {
+        // Load the default Python configuration as derived by the PyOxidizer config
+        // file used at build time.
+        let config = default_python_config();
+
+        // Construct a new Python interpreter using that config, handling any errors
+        // from construction.
+        match MainPythonInterpreter::new(config) {
+            Ok(mut interp) => {
+                // And run it using the default run configuration as specified by the
+                // configuration. If an uncaught Python exception is raised, handle it.
+                // This includes the special SystemExit, which is a request to terminate the
+                // process.
+                interp.run_as_main()
+            }
+            Err(msg) => {
+                eprintln!("{}", msg);
+                1
+            }
+        }
+    };
+
+    // And exit the process according to code execution results.
+    std::process::exit(code);
+}
diff --git a/setup.py b/setup.py
--- a/setup.py
+++ b/setup.py
@@ -568,7 +568,11 @@
 
 class hgbuildscripts(build_scripts):
     def run(self):
-        if os.name != 'nt' or self.distribution.pure:
+        if (
+            os.name != 'nt'
+            or self.distribution.pure
+            or 'PYOXIDIZER' in os.environ
+        ):
             return build_scripts.run(self)
 
         exebuilt = False