Swap pip for uv

[lmmx]

Is there an existing issue for this?

• I have searched existing issues, it hasn't been reported yet

Use case description

uv was just released (from the makers of ruff), and is substantially faster than pip, pip-tools, and virtualenv. This seems desirable to speed up serverless builds.

Proposed solution (optional)

Announcing uv: an extremely fast Python package installer and resolver, written in Rust.

uv is designed as a drop-in alternative to pip, pip-tools, and virtualenv.

With a warm cache, uv installs are near-instant. Here, it's > 75x faster than pip and pip-tools.

— Source

The “drop-in” claim seems to suggest you might be able to just change the binary i.e. re-alias pip to uv pip

[pgrzesik]

Hey @lmmx - how do you imagine support for uv on the plugin level? As the plugin uses pip that is installed locally, I think "just" aliasing on your own should be enough, but maybe I'm missing some specific use cases. Please let me know what do you think 🙇

[Zer0x00]

uv doesn't (yet) support the pip install -t flag with which you can specify a target directory.

This flag is used by this project to install the requirements into a cache directory or if you've disabled the cache to have the requirements under .serverless/requirements.

Zer0x00 ➜ /project $ uv pip install -t /project/.serverless/requirements -r /project/.serverless/requirements/requirements.txt

error: unexpected argument '-t' found

  tip: to pass '-t' as a value, use '-- -t'

Usage: uv pip install [OPTIONS] <PACKAGE|--requirement <REQUIREMENT>|--editable <EDITABLE>>

For more information, try '--help'.

[pgrzesik]

Thanks for sharing @Zer0x00 🙇 Unless there will be a very high demand for uv-specific support, I think the plugin shouldn't include anything specific for uv if the general plan for it is to be a drop-in replacement for pip with full compatibility.

If anyone is interested in having support for uv sooner, please vote on the issue with 👍 and/or write a comment below 🙇

[JP-Ellis]

This is something I really would like to see supported. I have recently transitioned from using pip to uv pip with some quite amazing speed ups across the board, and it would be great to have support for uv (or perhaps/eventually switch to uv entirely).

I have had success patching serverless-python-requirements manually with the following patch (be warned though, use at your own risk):

diff --git a/node_modules/serverless-python-requirements/lib/pip.js b/node_modules/serverless-python-requirements/lib/pip.js
index 40140d3..bfc75ab 100644
--- a/node_modules/serverless-python-requirements/lib/pip.js
+++ b/node_modules/serverless-python-requirements/lib/pip.js
@@ -147,7 +147,7 @@ async function installRequirements(targetFolder, pluginInstance, funcOptions) {

   try {
     const dockerCmd = [];
-    const pipCmd = [options.pythonBin, '-m', 'pip', 'install'];
+    const pipCmd = ['uv', 'pip', 'install', '--verbose', '--system'];

     if (
       Array.isArray(options.pipCmdExtraArgs) &&
@@ -159,7 +159,10 @@ async function installRequirements(targetFolder, pluginInstance, funcOptions) {
       });
     }

-    const pipCmds = [pipCmd];
+    const pipCmds = [
+      [options.pythonBin, '-m', 'pip', 'install', 'uv'],
+      pipCmd
+    ];
     const postCmds = [];
     // Check if we're using the legacy --cache-dir command...
     if (options.pipCmdExtraArgs.indexOf('--cache-dir') > -1) {
@@ -196,9 +199,9 @@ async function installRequirements(targetFolder, pluginInstance, funcOptions) {
     if (!options.dockerizePip) {
       // Push our local OS-specific paths for requirements and target directory
       pipCmd.push(
-        '-t',
+        '--target',
         dockerPathForWin(targetFolder),
-        '-r',
+        '--requirement',
         dockerPathForWin(targetRequirementsTxt)
       );
       // If we want a download cache...
@@ -226,7 +229,7 @@ async function installRequirements(targetFolder, pluginInstance, funcOptions) {
     // If we are dockerizing pip
     if (options.dockerizePip) {
       // Push docker-specific paths for requirements and target directory
-      pipCmd.push('-t', '/var/task/', '-r', '/var/task/requirements.txt');
+      pipCmd.push('--target', '/var/task/', '--requirement', '/var/task/requirements.txt');

       // Build docker image if required
       let dockerImage;

[zanieb]

Just a quick note

shouldn't include anything specific for uv if the general plan for it is to be a drop-in replacement for pip with full compatibility.

This was the idea for the initial release of uv, but now it supports lots of new functionality beyond pip. I'm not sure if that changes anything here :)

[lmmx]

uv added support for --target back in April 🙂 🎉

• Add -t/--target flag for uv pip install astral-sh/uv#1517

It is also now able to replace Pipenv:

• Question: Will it also replace pipenv? astral-sh/uv#1465

I would imagine that useUv could be put in as a switch the same way there is usePoetry for the poetry package manager