diff --git a/.env b/.env
index 39058d8d5..439560f09 100644
--- a/.env
+++ b/.env
@@ -1,2 +1,2 @@
 PATH=$PWD/bin:$PATH
-PUFFIN_TEST_PYTHON_PATH=$PWD/bin
+UV_TEST_PYTHON_PATH=$PWD/bin
diff --git a/crates/uv-cache/src/cli.rs b/crates/uv-cache/src/cli.rs
index fb7df391c..e4293367e 100644
--- a/crates/uv-cache/src/cli.rs
+++ b/crates/uv-cache/src/cli.rs
@@ -15,7 +15,7 @@ pub struct CacheArgs {
     no_cache: bool,
 
     /// Path to the cache directory.
-    #[arg(global = true, long, env = "PUFFIN_CACHE_DIR")]
+    #[arg(global = true, long, env = "UV_CACHE_DIR")]
     cache_dir: Option<PathBuf>,
 }
 
@@ -24,7 +24,7 @@ impl TryFrom<CacheArgs> for Cache {
 
     /// Prefer, in order:
     /// 1. A temporary cache directory, if the user requested `--no-cache`.
-    /// 2. The specific cache directory specified by the user via `--cache-dir` or `PUFFIN_CACHE_DIR`.
+    /// 2. The specific cache directory specified by the user via `--cache-dir` or `UV_CACHE_DIR`.
     /// 3. The system-appropriate cache directory.
     /// 4. A `.uv_cache` directory in the current working directory.
     ///
diff --git a/crates/uv-dev/src/resolve_cli.rs b/crates/uv-dev/src/resolve_cli.rs
index 5c74c674a..89678f071 100644
--- a/crates/uv-dev/src/resolve_cli.rs
+++ b/crates/uv-dev/src/resolve_cli.rs
@@ -43,7 +43,7 @@ pub(crate) struct ResolveCliArgs {
     cache_args: CacheArgs,
     #[arg(long)]
     exclude_newer: Option<DateTime<Utc>>,
-    #[clap(long, short, default_value = IndexUrl::Pypi.as_str(), env = "PUFFIN_INDEX_URL")]
+    #[clap(long, short, default_value = IndexUrl::Pypi.as_str(), env = "UV_INDEX_URL")]
     index_url: IndexUrl,
     #[clap(long)]
     extra_index_url: Vec<IndexUrl>,
diff --git a/crates/uv-interpreter/src/interpreter.rs b/crates/uv-interpreter/src/interpreter.rs
index 8fd6d0e0c..74ca950f9 100644
--- a/crates/uv-interpreter/src/interpreter.rs
+++ b/crates/uv-interpreter/src/interpreter.rs
@@ -136,7 +136,7 @@ impl Interpreter {
     /// - If a python version is given: `pythonx.y`
     /// - `python3` (unix) or `python.exe` (windows)
     ///
-    /// If `PUFFIN_TEST_PYTHON_PATH` is set, we will not check for Python versions in the
+    /// If `UV_TEST_PYTHON_PATH` is set, we will not check for Python versions in the
     /// global PATH, instead we will search using the provided path. Virtual environments
     /// will still be respected.
     ///
@@ -204,13 +204,13 @@ impl Interpreter {
         Ok(None)
     }
 
-    /// Find the Python interpreter in `PATH`, respecting `PUFFIN_PYTHON_PATH`.
+    /// Find the Python interpreter in `PATH`, respecting `UV_PYTHON_PATH`.
     ///
     /// Returns `Ok(None)` if not found.
     pub fn find_executable<R: AsRef<OsStr> + Into<OsString> + Copy>(
         requested: R,
     ) -> Result<Option<PathBuf>, Error> {
-        let result = if let Some(isolated) = std::env::var_os("PUFFIN_TEST_PYTHON_PATH") {
+        let result = if let Some(isolated) = std::env::var_os("UV_TEST_PYTHON_PATH") {
             which::which_in(requested, Some(isolated), std::env::current_dir()?)
         } else {
             which::which(requested)
diff --git a/crates/uv-interpreter/src/python_query.rs b/crates/uv-interpreter/src/python_query.rs
index 20a4ab30e..8a0176efc 100644
--- a/crates/uv-interpreter/src/python_query.rs
+++ b/crates/uv-interpreter/src/python_query.rs
@@ -68,7 +68,7 @@ pub fn find_requested_python(
                 Interpreter::query(&executable, platform, cache)?
             }
         } else if cfg!(windows) {
-            if let Some(python_overwrite) = env::var_os("PUFFIN_TEST_PYTHON_PATH") {
+            if let Some(python_overwrite) = env::var_os("UV_TEST_PYTHON_PATH") {
                 let executable_dir = env::split_paths(&python_overwrite).find(|path| {
                     path.as_os_str()
                         .to_str()
@@ -140,25 +140,21 @@ pub fn find_requested_python(
 
 /// Pick a sensible default for the python a user wants when they didn't specify a version.
 ///
-/// We prefer the test overwrite `PUFFIN_TEST_PYTHON_PATH` if it is set, otherwise `python3`/`python` or
+/// We prefer the test overwrite `UV_TEST_PYTHON_PATH` if it is set, otherwise `python3`/`python` or
 /// `python.exe` respectively.
 #[instrument]
 pub fn find_default_python(platform: &Platform, cache: &Cache) -> Result<Interpreter, Error> {
     let current_dir = env::current_dir()?;
     let python = if cfg!(unix) {
-        which::which_in(
-            "python3",
-            env::var_os("PUFFIN_TEST_PYTHON_PATH"),
-            current_dir,
-        )
-        .or_else(|_| which::which("python"))
-        .map_err(|_| Error::NoPythonInstalledUnix)?
+        which::which_in("python3", env::var_os("UV_TEST_PYTHON_PATH"), current_dir)
+            .or_else(|_| which::which("python"))
+            .map_err(|_| Error::NoPythonInstalledUnix)?
     } else if cfg!(windows) {
         // TODO(konstin): Is that the right order, or should we look for `py --list-paths` first? With the current way
         // it works even if the python launcher is not installed.
         if let Ok(python) = which::which_in(
             "python.exe",
-            env::var_os("PUFFIN_TEST_PYTHON_PATH"),
+            env::var_os("UV_TEST_PYTHON_PATH"),
             current_dir,
         ) {
             python
@@ -182,7 +178,7 @@ pub fn find_default_python(platform: &Platform, cache: &Cache) -> Result<Interpr
 /// The command takes 8ms on my machine. TODO(konstin): Implement <https://peps.python.org/pep-0514/> to read python
 /// installations from the registry instead.
 fn installed_pythons_windows() -> Result<Vec<(u8, u8, PathBuf)>, Error> {
-    // TODO(konstin): We're not checking PUFFIN_TEST_PYTHON_PATH here, no test currently depends on it.
+    // TODO(konstin): We're not checking UV_TEST_PYTHON_PATH here, no test currently depends on it.
 
     // TODO(konstin): Special case the not found error
     let output = info_span!("py_list_paths")
@@ -223,7 +219,7 @@ fn installed_pythons_windows() -> Result<Vec<(u8, u8, PathBuf)>, Error> {
 }
 
 pub(crate) fn find_python_windows(major: u8, minor: u8) -> Result<Option<PathBuf>, Error> {
-    if let Some(python_overwrite) = env::var_os("PUFFIN_TEST_PYTHON_PATH") {
+    if let Some(python_overwrite) = env::var_os("UV_TEST_PYTHON_PATH") {
         let executable_dir = env::split_paths(&python_overwrite).find(|path| {
             path.as_os_str()
                 .to_str()
diff --git a/crates/uv/src/main.rs b/crates/uv/src/main.rs
index f0d91635d..48b6e2785 100644
--- a/crates/uv/src/main.rs
+++ b/crates/uv/src/main.rs
@@ -234,7 +234,7 @@ struct PipCompileArgs {
     refresh_package: Vec<PackageName>,
 
     /// The URL of the Python Package Index.
-    #[clap(long, short, default_value = IndexUrl::Pypi.as_str(), env = "PUFFIN_INDEX_URL")]
+    #[clap(long, short, default_value = IndexUrl::Pypi.as_str(), env = "UV_INDEX_URL")]
     index_url: IndexUrl,
 
     /// Extra URLs of package indexes to use, in addition to `--index-url`.
@@ -358,7 +358,7 @@ struct PipSyncArgs {
     link_mode: install_wheel_rs::linker::LinkMode,
 
     /// The URL of the Python Package Index.
-    #[clap(long, short, default_value = IndexUrl::Pypi.as_str(), env = "PUFFIN_INDEX_URL")]
+    #[clap(long, short, default_value = IndexUrl::Pypi.as_str(), env = "UV_INDEX_URL")]
     index_url: IndexUrl,
 
     /// Extra URLs of package indexes to use, in addition to `--index-url`.
@@ -515,7 +515,7 @@ struct PipInstallArgs {
     output_file: Option<PathBuf>,
 
     /// The URL of the Python Package Index.
-    #[clap(long, short, default_value = IndexUrl::Pypi.as_str(), env = "PUFFIN_INDEX_URL")]
+    #[clap(long, short, default_value = IndexUrl::Pypi.as_str(), env = "UV_INDEX_URL")]
     index_url: IndexUrl,
 
     /// Extra URLs of package indexes to use, in addition to `--index-url`.
@@ -644,7 +644,7 @@ struct VenvArgs {
     name: PathBuf,
 
     /// The URL of the Python Package Index.
-    #[clap(long, short, default_value = IndexUrl::Pypi.as_str(), env = "PUFFIN_INDEX_URL")]
+    #[clap(long, short, default_value = IndexUrl::Pypi.as_str(), env = "UV_INDEX_URL")]
     index_url: IndexUrl,
 
     /// Extra URLs of package indexes to use, in addition to `--index-url`.
@@ -770,7 +770,7 @@ async fn run() -> Result<ExitStatus> {
                 .break_words(false)
                 .word_separator(textwrap::WordSeparator::AsciiSpace)
                 .word_splitter(textwrap::WordSplitter::NoHyphenation)
-                .wrap_lines(env::var("PUFFIN_NO_WRAP").map(|_| false).unwrap_or(true))
+                .wrap_lines(env::var("UV_NO_WRAP").map(|_| false).unwrap_or(true))
                 .build(),
         )
     }))?;
@@ -1022,7 +1022,7 @@ async fn run() -> Result<ExitStatus> {
 }
 
 fn main() -> ExitCode {
-    let result = if let Ok(stack_size) = env::var("PUFFIN_STACK_SIZE") {
+    let result = if let Ok(stack_size) = env::var("UV_STACK_SIZE") {
         // Artificially limit the stack size to test for stack overflows. Windows has a default stack size of 1MB,
         // which is lower than the linux and mac default.
         // https://learn.microsoft.com/en-us/cpp/build/reference/stack-stack-allocations?view=msvc-170
diff --git a/crates/uv/tests/pip_compile_scenarios.rs b/crates/uv/tests/pip_compile_scenarios.rs
index 96bb81486..1d840e7f6 100644
--- a/crates/uv/tests/pip_compile_scenarios.rs
+++ b/crates/uv/tests/pip_compile_scenarios.rs
@@ -31,8 +31,8 @@ fn command(context: &TestContext, python_versions: &[&str]) -> Command {
         .arg("--cache-dir")
         .arg(context.cache_dir.path())
         .env("VIRTUAL_ENV", context.venv.as_os_str())
-        .env("PUFFIN_NO_WRAP", "1")
-        .env("PUFFIN_TEST_PYTHON_PATH", bin)
+        .env("UV_NO_WRAP", "1")
+        .env("UV_TEST_PYTHON_PATH", bin)
         .current_dir(&context.temp_dir);
     command
 }
diff --git a/crates/uv/tests/pip_install.rs b/crates/uv/tests/pip_install.rs
index f210969b1..d9cabf262 100644
--- a/crates/uv/tests/pip_install.rs
+++ b/crates/uv/tests/pip_install.rs
@@ -673,7 +673,7 @@ fn reinstall_no_binary() {
     if cfg!(all(windows, debug_assertions)) {
         // TODO(konstin): Reduce stack usage in debug mode enough that the tests pass with the
         // default windows stack of 1MB
-        command.env("PUFFIN_STACK_SIZE", (2 * 1024 * 1024).to_string());
+        command.env("UV_STACK_SIZE", (2 * 1024 * 1024).to_string());
     }
     uv_snapshot!(command, @r###"
     success: true
@@ -703,7 +703,7 @@ fn reinstall_no_binary() {
     if cfg!(all(windows, debug_assertions)) {
         // TODO(konstin): Reduce stack usage in debug mode enough that the tests pass with the
         // default windows stack of 1MB
-        command.env("PUFFIN_STACK_SIZE", (2 * 1024 * 1024).to_string());
+        command.env("UV_STACK_SIZE", (2 * 1024 * 1024).to_string());
     }
     uv_snapshot!(command, @r###"
     success: true
@@ -739,7 +739,7 @@ fn reinstall_no_binary() {
     if cfg!(all(windows, debug_assertions)) {
         // TODO(konstin): Reduce stack usage in debug mode enough that the tests pass with the
         // default windows stack of 1MB
-        command.env("PUFFIN_STACK_SIZE", (2 * 1024 * 1024).to_string());
+        command.env("UV_STACK_SIZE", (2 * 1024 * 1024).to_string());
     }
     uv_snapshot!(filters, command, @r###"
     success: true
diff --git a/crates/uv/tests/pip_install_scenarios.rs b/crates/uv/tests/pip_install_scenarios.rs
index 5b65aaba6..7fceab261 100644
--- a/crates/uv/tests/pip_install_scenarios.rs
+++ b/crates/uv/tests/pip_install_scenarios.rs
@@ -50,7 +50,7 @@ fn command(context: &TestContext) -> Command {
         .arg("--cache-dir")
         .arg(context.cache_dir.path())
         .env("VIRTUAL_ENV", context.venv.as_os_str())
-        .env("PUFFIN_NO_WRAP", "1")
+        .env("UV_NO_WRAP", "1")
         .current_dir(&context.temp_dir);
     command
 }
diff --git a/crates/uv/tests/pip_sync.rs b/crates/uv/tests/pip_sync.rs
index e6d6f2106..9eda54d5a 100644
--- a/crates/uv/tests/pip_sync.rs
+++ b/crates/uv/tests/pip_sync.rs
@@ -329,7 +329,7 @@ fn link() -> Result<()> {
         .arg(context.cache_dir.path())
         .arg("--python")
         .arg("3.12")
-        .env("PUFFIN_TEST_PYTHON_PATH", bin)
+        .env("UV_TEST_PYTHON_PATH", bin)
         .current_dir(&context.temp_dir)
         .assert()
         .success();
diff --git a/crates/uv/tests/venv.rs b/crates/uv/tests/venv.rs
index 79ea1c3f9..5b4030149 100644
--- a/crates/uv/tests/venv.rs
+++ b/crates/uv/tests/venv.rs
@@ -36,7 +36,7 @@ fn create_venv() -> Result<()> {
         .arg(cache_dir.path())
         .arg("--exclude-newer")
         .arg(EXCLUDE_NEWER)
-        .env("PUFFIN_TEST_PYTHON_PATH", bin.clone())
+        .env("UV_TEST_PYTHON_PATH", bin.clone())
         .current_dir(&temp_dir), @r###"
     success: true
     exit_code: 0
@@ -68,8 +68,8 @@ fn create_venv() -> Result<()> {
         .arg(cache_dir.path())
         .arg("--exclude-newer")
         .arg(EXCLUDE_NEWER)
-        .env("PUFFIN_NO_WRAP", "1")
-        .env("PUFFIN_TEST_PYTHON_PATH", bin)
+        .env("UV_NO_WRAP", "1")
+        .env("UV_TEST_PYTHON_PATH", bin)
         .current_dir(&temp_dir), @r###"
     success: true
     exit_code: 0
@@ -109,8 +109,8 @@ fn create_venv_defaults_to_cwd() -> Result<()> {
         .arg(cache_dir.path())
         .arg("--exclude-newer")
         .arg(EXCLUDE_NEWER)
-        .env("PUFFIN_NO_WRAP", "1")
-        .env("PUFFIN_TEST_PYTHON_PATH", bin)
+        .env("UV_NO_WRAP", "1")
+        .env("UV_TEST_PYTHON_PATH", bin)
         .current_dir(&temp_dir), @r###"
     success: true
     exit_code: 0
@@ -152,8 +152,8 @@ fn seed() -> Result<()> {
         .arg(cache_dir.path())
         .arg("--exclude-newer")
         .arg(EXCLUDE_NEWER)
-        .env("PUFFIN_NO_WRAP", "1")
-        .env("PUFFIN_TEST_PYTHON_PATH", bin)
+        .env("UV_NO_WRAP", "1")
+        .env("UV_TEST_PYTHON_PATH", bin)
         .current_dir(&temp_dir), @r###"
     success: true
     exit_code: 0
@@ -190,8 +190,8 @@ fn create_venv_unknown_python_minor() -> Result<()> {
         .arg(cache_dir.path())
         .arg("--exclude-newer")
         .arg(EXCLUDE_NEWER)
-        .env("PUFFIN_NO_WRAP", "1")
-        .env("PUFFIN_TEST_PYTHON_PATH", bin)
+        .env("UV_NO_WRAP", "1")
+        .env("UV_TEST_PYTHON_PATH", bin)
         .current_dir(&temp_dir);
     if cfg!(windows) {
         uv_snapshot!(&mut command, @r###"
@@ -245,8 +245,8 @@ fn create_venv_unknown_python_patch() -> Result<()> {
         .arg(cache_dir.path())
         .arg("--exclude-newer")
         .arg(EXCLUDE_NEWER)
-        .env("PUFFIN_NO_WRAP", "1")
-        .env("PUFFIN_TEST_PYTHON_PATH", bin)
+        .env("UV_NO_WRAP", "1")
+        .env("UV_TEST_PYTHON_PATH", bin)
         .current_dir(&temp_dir), @r###"
     success: false
     exit_code: 1
@@ -286,8 +286,8 @@ fn create_venv_python_patch() -> Result<()> {
         .arg(cache_dir.path())
         .arg("--exclude-newer")
         .arg(EXCLUDE_NEWER)
-        .env("PUFFIN_NO_WRAP", "1")
-        .env("PUFFIN_TEST_PYTHON_PATH", bin)
+        .env("UV_NO_WRAP", "1")
+        .env("UV_TEST_PYTHON_PATH", bin)
         .current_dir(&temp_dir), @r###"
     success: true
     exit_code: 0
@@ -331,8 +331,8 @@ fn file_exists() -> Result<()> {
         .arg(cache_dir.path())
         .arg("--exclude-newer")
         .arg(EXCLUDE_NEWER)
-        .env("PUFFIN_NO_WRAP", "1")
-        .env("PUFFIN_TEST_PYTHON_PATH", bin)
+        .env("UV_NO_WRAP", "1")
+        .env("UV_TEST_PYTHON_PATH", bin)
         .current_dir(&temp_dir), @r###"
     success: false
     exit_code: 1
@@ -378,8 +378,8 @@ fn empty_dir_exists() -> Result<()> {
         .arg(cache_dir.path())
         .arg("--exclude-newer")
         .arg(EXCLUDE_NEWER)
-        .env("PUFFIN_NO_WRAP", "1")
-        .env("PUFFIN_TEST_PYTHON_PATH", bin)
+        .env("UV_NO_WRAP", "1")
+        .env("UV_TEST_PYTHON_PATH", bin)
         .current_dir(&temp_dir), @r###"
     success: true
     exit_code: 0
@@ -424,8 +424,8 @@ fn non_empty_dir_exists() -> Result<()> {
         .arg(cache_dir.path())
         .arg("--exclude-newer")
         .arg(EXCLUDE_NEWER)
-        .env("PUFFIN_NO_WRAP", "1")
-        .env("PUFFIN_TEST_PYTHON_PATH", bin)
+        .env("UV_NO_WRAP", "1")
+        .env("UV_TEST_PYTHON_PATH", bin)
         .current_dir(&temp_dir), @r###"
     success: false
     exit_code: 1
@@ -470,7 +470,7 @@ fn virtualenv_compatibility() -> Result<()> {
         .arg(cache_dir.path())
         .arg("--exclude-newer")
         .arg(EXCLUDE_NEWER)
-        .env("PUFFIN_TEST_PYTHON_PATH", bin.clone())
+        .env("UV_TEST_PYTHON_PATH", bin.clone())
         .current_dir(&temp_dir), @r###"
     success: true
     exit_code: 0
diff --git a/scripts/scenarios/templates/compile.mustache b/scripts/scenarios/templates/compile.mustache
index 0f4750f61..7244754f7 100644
--- a/scripts/scenarios/templates/compile.mustache
+++ b/scripts/scenarios/templates/compile.mustache
@@ -31,8 +31,8 @@ fn command(context: &TestContext, python_versions: &[&str]) -> Command {
         .arg("--cache-dir")
         .arg(context.cache_dir.path())
         .env("VIRTUAL_ENV", context.venv.as_os_str())
-        .env("PUFFIN_NO_WRAP", "1")
-        .env("PUFFIN_TEST_PYTHON_PATH", bin)
+        .env("UV_NO_WRAP", "1")
+        .env("UV_TEST_PYTHON_PATH", bin)
         .current_dir(&context.temp_dir);
     command
 }
diff --git a/scripts/scenarios/templates/install.mustache b/scripts/scenarios/templates/install.mustache
index cbcae68f4..3a1bcbd13 100644
--- a/scripts/scenarios/templates/install.mustache
+++ b/scripts/scenarios/templates/install.mustache
@@ -51,7 +51,7 @@ fn command(context: &TestContext) -> Command {
         .arg("--cache-dir")
         .arg(context.cache_dir.path())
         .env("VIRTUAL_ENV", context.venv.as_os_str())
-        .env("PUFFIN_NO_WRAP", "1")
+        .env("UV_NO_WRAP", "1")
         .current_dir(&context.temp_dir);
     command
 }
diff --git a/scripts/scenarios/update.py b/scripts/scenarios/update.py
index ef788c978..334a76d03 100755
--- a/scripts/scenarios/update.py
+++ b/scripts/scenarios/update.py
@@ -24,7 +24,7 @@ Usage:
 
         Override the default PyPI index for uv and update the scenarios
 
-        $ PUFFIN_INDEX_URL="http://localhost:3141/packages/all/+simple" ./scripts/scenarios/update.py
+        $ UV_INDEX_URL="http://localhost:3141/packages/all/+simple" ./scripts/scenarios/update.py
 
 Requirements: