Add UV_VENV_SEED environment variable (#10715)

## Summary

Closes #7655.

crates/uv-cli/src/lib.rs

@@ -2365,8 +2365,8 @@ pub struct VenvArgs {
 
     /// Install seed packages (one or more of: `pip`, `setuptools`, and `wheel`) into the virtual environment.
     ///
-    /// Note `setuptools` and `wheel` are not included in Python 3.12+ environments.
-    #[arg(long)]
+    /// Note that `setuptools` and `wheel` are not included in Python 3.12+ environments.
+    #[arg(long, value_parser = clap::builder::BoolishValueParser::new(), env = EnvVars::UV_VENV_SEED)]
     pub seed: bool,
 
     /// Preserve any existing files or directories at the target path.

crates/uv-static/src/env_vars.rs

@@ -234,6 +234,12 @@ impl EnvVars {
     /// Distributions can be read from a local directory by using the `file://` URL scheme.
     pub const UV_PYPY_INSTALL_MIRROR: &'static str = "UV_PYPY_INSTALL_MIRROR";
 
+    /// Install seed packages (one or more of: `pip`, `setuptools`, and `wheel`) into the virtual environment
+    /// created by `uv venv`.
+    ///
+    /// Note that `setuptools` and `wheel` are not included in Python 3.12+ environments.
+    pub const UV_VENV_SEED: &'static str = "UV_VENV_SEED";
+
     /// Used to override `PATH` to limit Python executable availability in the test suite.
     #[attr_hidden]
     pub const UV_TEST_PYTHON_PATH: &'static str = "UV_TEST_PYTHON_PATH";

docs/configuration/environment.md

@@ -341,6 +341,13 @@ Specifies the directory where uv stores managed tools.
 Used ephemeral environments like CI to install uv to a specific path while preventing
 the installer from modifying shell profiles or environment variables.
 
+### `UV_VENV_SEED`
+
+Install seed packages (one or more of: `pip`, `setuptools`, and `wheel`) into the virtual environment
+created by `uv venv`.
+
+Note that `setuptools` and `wheel` are not included in Python 3.12+ environments.
+
 
 
 ## Externally defined variables

docs/reference/cli.md

@@ -8072,8 +8072,9 @@ uv venv [OPTIONS] [PATH]
 
 </dd><dt><code>--seed</code></dt><dd><p>Install seed packages (one or more of: <code>pip</code>, <code>setuptools</code>, and <code>wheel</code>) into the virtual environment.</p>
 
-<p>Note <code>setuptools</code> and <code>wheel</code> are not included in Python 3.12+ environments.</p>
+<p>Note that <code>setuptools</code> and <code>wheel</code> are not included in Python 3.12+ environments.</p>
 
+<p>May also be set with the <code>UV_VENV_SEED</code> environment variable.</p>
 </dd><dt><code>--system-site-packages</code></dt><dd><p>Give the virtual environment access to the system site packages directory.</p>
 
 <p>Unlike <code>pip</code>, when a virtual environment is created with <code>--system-site-packages</code>, uv will <em>not</em> take system site packages into account when running commands like <code>uv pip list</code> or <code>uv pip install</code>. The <code>--system-site-packages</code> flag will provide the virtual environment with access to the system site packages directory at runtime, but will not affect the behavior of uv commands.</p>