diff --git a/crates/uv-build-backend/src/lib.rs b/crates/uv-build-backend/src/lib.rs
index 441213a90..852e8c651 100644
--- a/crates/uv-build-backend/src/lib.rs
+++ b/crates/uv-build-backend/src/lib.rs
@@ -1,3 +1,4 @@
+use itertools::Itertools;
 mod metadata;
 mod serde_verbatim;
 mod settings;
@@ -7,8 +8,10 @@ mod wheel;
 pub use metadata::{PyProjectToml, check_direct_build};
 pub use settings::{BuildBackendSettings, WheelDataIncludes};
 pub use source_dist::{build_source_dist, list_source_dist};
+use uv_warnings::warn_user_once;
 pub use wheel::{build_editable, build_wheel, list_wheel, metadata};
 
+use std::collections::HashSet;
 use std::ffi::OsStr;
 use std::io;
 use std::path::{Path, PathBuf};
@@ -191,6 +194,60 @@ fn check_metadata_directory(
     Ok(())
 }
 
+/// Returns the list of module names without names which would be included twice
+///
+/// In normal cases it should do nothing:
+///
+/// * `["aaa"] -> ["aaa"]`
+/// * `["aaa", "bbb"] -> ["aaa", "bbb"]`
+///
+/// Duplicate elements are removed:
+///
+/// * `["aaa", "aaa"] -> ["aaa"]`
+/// * `["bbb", "aaa", "bbb"] -> ["aaa", "bbb"]`
+///
+/// Names with more specific paths are removed in favour of more general paths:
+///
+/// * `["aaa.foo", "aaa"] -> ["aaa"]`
+/// * `["bbb", "aaa", "bbb.foo", "ccc.foo", "ccc.foo.bar", "aaa"] -> ["aaa", "bbb.foo", "ccc.foo"]`
+///
+/// This does not preserve the order of the elements.
+fn prune_redundant_modules(mut names: Vec<String>) -> Vec<String> {
+    names.sort();
+    let mut pruned = Vec::with_capacity(names.len());
+    for name in names {
+        if let Some(last) = pruned.last() {
+            if name == *last {
+                continue;
+            }
+            // This is a more specific (narrow) module name than what came before
+            if name
+                .strip_prefix(last)
+                .is_some_and(|suffix| suffix.starts_with('.'))
+            {
+                continue;
+            }
+        }
+        pruned.push(name);
+    }
+    pruned
+}
+
+/// Wraps [`prune_redundant_modules`] with a conditional warning when modules are ignored
+fn prune_redundant_modules_warn(names: &[String], show_warnings: bool) -> Vec<String> {
+    let pruned = prune_redundant_modules(names.to_vec());
+    if show_warnings && names.len() != pruned.len() {
+        let mut pruned: HashSet<_> = pruned.iter().collect();
+        let ignored: Vec<_> = names.iter().filter(|name| !pruned.remove(name)).collect();
+        let s = if ignored.len() == 1 { "" } else { "s" };
+        warn_user_once!(
+            "Ignoring redundant module name{s} in `tool.uv.build-backend.module-name`: `{}`",
+            ignored.into_iter().join("`, `")
+        );
+    }
+    pruned
+}
+
 /// Returns the source root and the module path(s) with the `__init__.py[i]`  below to it while
 /// checking the project layout and names.
 ///
@@ -213,6 +270,7 @@ fn find_roots(
     relative_module_root: &Path,
     module_name: Option<&ModuleName>,
     namespace: bool,
+    show_warnings: bool,
 ) -> Result<(PathBuf, Vec<PathBuf>), Error> {
     let relative_module_root = uv_fs::normalize_path(relative_module_root);
     // Check that even if a path contains `..`, we only include files below the module root.
@@ -231,8 +289,8 @@ fn find_roots(
                 ModuleName::Name(name) => {
                     vec![name.split('.').collect::<PathBuf>()]
                 }
-                ModuleName::Names(names) => names
-                    .iter()
+                ModuleName::Names(names) => prune_redundant_modules_warn(names, show_warnings)
+                    .into_iter()
                     .map(|name| name.split('.').collect::<PathBuf>())
                     .collect(),
             }
@@ -250,9 +308,9 @@ fn find_roots(
     let modules_relative = if let Some(module_name) = module_name {
         match module_name {
             ModuleName::Name(name) => vec![module_path_from_module_name(&src_root, name)?],
-            ModuleName::Names(names) => names
-                .iter()
-                .map(|name| module_path_from_module_name(&src_root, name))
+            ModuleName::Names(names) => prune_redundant_modules_warn(names, show_warnings)
+                .into_iter()
+                .map(|name| module_path_from_module_name(&src_root, &name))
                 .collect::<Result<_, _>>()?,
         }
     } else {
@@ -420,19 +478,20 @@ mod tests {
     fn build(source_root: &Path, dist: &Path) -> Result<BuildResults, Error> {
         // Build a direct wheel, capture all its properties to compare it with the indirect wheel
         // latest and remove it since it has the same filename as the indirect wheel.
-        let (_name, direct_wheel_list_files) = list_wheel(source_root, MOCK_UV_VERSION)?;
-        let direct_wheel_filename = build_wheel(source_root, dist, None, MOCK_UV_VERSION)?;
+        let (_name, direct_wheel_list_files) = list_wheel(source_root, MOCK_UV_VERSION, false)?;
+        let direct_wheel_filename = build_wheel(source_root, dist, None, MOCK_UV_VERSION, false)?;
         let direct_wheel_path = dist.join(direct_wheel_filename.to_string());
         let direct_wheel_contents = wheel_contents(&direct_wheel_path);
         let direct_wheel_hash = sha2::Sha256::digest(fs_err::read(&direct_wheel_path)?);
         fs_err::remove_file(&direct_wheel_path)?;
 
         // Build a source distribution.
-        let (_name, source_dist_list_files) = list_source_dist(source_root, MOCK_UV_VERSION)?;
+        let (_name, source_dist_list_files) =
+            list_source_dist(source_root, MOCK_UV_VERSION, false)?;
         // TODO(konsti): This should run in the unpacked source dist tempdir, but we need to
         // normalize the path.
-        let (_name, wheel_list_files) = list_wheel(source_root, MOCK_UV_VERSION)?;
-        let source_dist_filename = build_source_dist(source_root, dist, MOCK_UV_VERSION)?;
+        let (_name, wheel_list_files) = list_wheel(source_root, MOCK_UV_VERSION, false)?;
+        let source_dist_filename = build_source_dist(source_root, dist, MOCK_UV_VERSION, false)?;
         let source_dist_path = dist.join(source_dist_filename.to_string());
         let source_dist_contents = sdist_contents(&source_dist_path);
 
@@ -446,7 +505,13 @@ mod tests {
             source_dist_filename.name.as_dist_info_name(),
             source_dist_filename.version
         ));
-        let wheel_filename = build_wheel(&sdist_top_level_directory, dist, None, MOCK_UV_VERSION)?;
+        let wheel_filename = build_wheel(
+            &sdist_top_level_directory,
+            dist,
+            None,
+            MOCK_UV_VERSION,
+            false,
+        )?;
         let wheel_contents = wheel_contents(&dist.join(wheel_filename.to_string()));
 
         // Check that direct and indirect wheels are identical.
@@ -756,7 +821,7 @@ mod tests {
 
         // Build a wheel from a source distribution
         let output_dir = TempDir::new().unwrap();
-        build_source_dist(src.path(), output_dir.path(), "0.5.15").unwrap();
+        build_source_dist(src.path(), output_dir.path(), "0.5.15", false).unwrap();
         let sdist_tree = TempDir::new().unwrap();
         let source_dist_path = output_dir.path().join("pep_pep639_license-1.0.0.tar.gz");
         let sdist_reader = BufReader::new(File::open(&source_dist_path).unwrap());
@@ -767,6 +832,7 @@ mod tests {
             output_dir.path(),
             None,
             "0.5.15",
+            false,
         )
         .unwrap();
         let wheel = output_dir
@@ -831,6 +897,7 @@ mod tests {
             output_dir.path(),
             Some(&metadata_dir.path().join(&dist_info_dir)),
             "0.5.15",
+            false,
         )
         .unwrap();
         let wheel = output_dir
@@ -1414,4 +1481,114 @@ mod tests {
         simple_namespace_part-1.0.0.dist-info/WHEEL
         ");
     }
+
+    /// `prune_redundant_modules` should remove modules which are already
+    /// included (either directly or via their parent)
+    #[test]
+    fn test_prune_redundant_modules() {
+        fn check(input: &[&str], expect: &[&str]) {
+            let input = input.iter().map(|s| (*s).to_string()).collect();
+            let expect: Vec<_> = expect.iter().map(|s| (*s).to_string()).collect();
+            assert_eq!(prune_redundant_modules(input), expect);
+        }
+
+        // Basic cases
+        check(&[], &[]);
+        check(&["foo"], &["foo"]);
+        check(&["foo", "bar"], &["bar", "foo"]);
+
+        // Deshadowing
+        check(&["foo", "foo.bar"], &["foo"]);
+        check(&["foo.bar", "foo"], &["foo"]);
+        check(
+            &["foo.bar.a", "foo.bar.b", "foo.bar", "foo", "foo.bar.a.c"],
+            &["foo"],
+        );
+        check(
+            &["bar.one", "bar.two", "baz", "bar", "baz.one"],
+            &["bar", "baz"],
+        );
+
+        // Potential false positives
+        check(&["foo", "foobar"], &["foo", "foobar"]);
+        check(
+            &["foo", "foobar", "foo.bar", "foobar.baz"],
+            &["foo", "foobar"],
+        );
+        check(&["foo.bar", "foo.baz"], &["foo.bar", "foo.baz"]);
+        check(&["foo", "foo", "foo.bar", "foo.bar"], &["foo"]);
+
+        // Everything
+        check(
+            &[
+                "foo.inner",
+                "foo.inner.deeper",
+                "foo",
+                "bar",
+                "bar.sub",
+                "bar.sub.deep",
+                "foobar",
+                "baz.baz.bar",
+                "baz.baz",
+                "qux",
+            ],
+            &["bar", "baz.baz", "foo", "foobar", "qux"],
+        );
+    }
+
+    /// A package with duplicate module names.
+    #[test]
+    fn duplicate_module_names() {
+        let src = TempDir::new().unwrap();
+        let pyproject_toml = indoc! {r#"
+            [project]
+            name = "duplicate"
+            version = "1.0.0"
+
+            [tool.uv.build-backend]
+            module-name = ["foo", "foo", "bar.baz", "bar.baz.submodule"]
+
+            [build-system]
+            requires = ["uv_build>=0.5.15,<0.6.0"]
+            build-backend = "uv_build"
+            "#
+        };
+        fs_err::write(src.path().join("pyproject.toml"), pyproject_toml).unwrap();
+        fs_err::create_dir_all(src.path().join("src").join("foo")).unwrap();
+        File::create(src.path().join("src").join("foo").join("__init__.py")).unwrap();
+        fs_err::create_dir_all(src.path().join("src").join("bar").join("baz")).unwrap();
+        File::create(
+            src.path()
+                .join("src")
+                .join("bar")
+                .join("baz")
+                .join("__init__.py"),
+        )
+        .unwrap();
+
+        let dist = TempDir::new().unwrap();
+        let build = build(src.path(), dist.path()).unwrap();
+        assert_snapshot!(build.source_dist_contents.join("\n"), @r"
+        duplicate-1.0.0/
+        duplicate-1.0.0/PKG-INFO
+        duplicate-1.0.0/pyproject.toml
+        duplicate-1.0.0/src
+        duplicate-1.0.0/src/bar
+        duplicate-1.0.0/src/bar/baz
+        duplicate-1.0.0/src/bar/baz/__init__.py
+        duplicate-1.0.0/src/foo
+        duplicate-1.0.0/src/foo/__init__.py
+        ");
+        assert_snapshot!(build.wheel_contents.join("\n"), @r"
+        bar/
+        bar/baz/
+        bar/baz/__init__.py
+        duplicate-1.0.0.dist-info/
+        duplicate-1.0.0.dist-info/METADATA
+        duplicate-1.0.0.dist-info/RECORD
+        duplicate-1.0.0.dist-info/WHEEL
+        foo/
+        foo/__init__.py
+        ");
+    }
 }
diff --git a/crates/uv-build-backend/src/source_dist.rs b/crates/uv-build-backend/src/source_dist.rs
index 09eac992d..7059985ea 100644
--- a/crates/uv-build-backend/src/source_dist.rs
+++ b/crates/uv-build-backend/src/source_dist.rs
@@ -24,6 +24,7 @@ pub fn build_source_dist(
     source_tree: &Path,
     source_dist_directory: &Path,
     uv_version: &str,
+    show_warnings: bool,
 ) -> Result<SourceDistFilename, Error> {
     let contents = fs_err::read_to_string(source_tree.join("pyproject.toml"))?;
     let pyproject_toml = PyProjectToml::parse(&contents)?;
@@ -34,7 +35,7 @@ pub fn build_source_dist(
     };
     let source_dist_path = source_dist_directory.join(filename.to_string());
     let writer = TarGzWriter::new(&source_dist_path)?;
-    write_source_dist(source_tree, writer, uv_version)?;
+    write_source_dist(source_tree, writer, uv_version, show_warnings)?;
     Ok(filename)
 }
 
@@ -42,6 +43,7 @@ pub fn build_source_dist(
 pub fn list_source_dist(
     source_tree: &Path,
     uv_version: &str,
+    show_warnings: bool,
 ) -> Result<(SourceDistFilename, FileList), Error> {
     let contents = fs_err::read_to_string(source_tree.join("pyproject.toml"))?;
     let pyproject_toml = PyProjectToml::parse(&contents)?;
@@ -52,7 +54,7 @@ pub fn list_source_dist(
     };
     let mut files = FileList::new();
     let writer = ListWriter::new(&mut files);
-    write_source_dist(source_tree, writer, uv_version)?;
+    write_source_dist(source_tree, writer, uv_version, show_warnings)?;
     Ok((filename, files))
 }
 
@@ -61,6 +63,7 @@ fn source_dist_matcher(
     source_tree: &Path,
     pyproject_toml: &PyProjectToml,
     settings: BuildBackendSettings,
+    show_warnings: bool,
 ) -> Result<(GlobDirFilter, GlobSet), Error> {
     // File and directories to include in the source directory
     let mut include_globs = Vec::new();
@@ -75,6 +78,7 @@ fn source_dist_matcher(
         &settings.module_root,
         settings.module_name.as_ref(),
         settings.namespace,
+        show_warnings,
     )?;
     for module_relative in modules_relative {
         // The wheel must not include any files included by the source distribution (at least until we
@@ -182,6 +186,7 @@ fn write_source_dist(
     source_tree: &Path,
     mut writer: impl DirectoryWriter,
     uv_version: &str,
+    show_warnings: bool,
 ) -> Result<SourceDistFilename, Error> {
     let contents = fs_err::read_to_string(source_tree.join("pyproject.toml"))?;
     let pyproject_toml = PyProjectToml::parse(&contents)?;
@@ -218,7 +223,7 @@ fn write_source_dist(
     )?;
 
     let (include_matcher, exclude_matcher) =
-        source_dist_matcher(source_tree, &pyproject_toml, settings)?;
+        source_dist_matcher(source_tree, &pyproject_toml, settings, show_warnings)?;
 
     let mut files_visited = 0;
     for entry in WalkDir::new(source_tree)
diff --git a/crates/uv-build-backend/src/wheel.rs b/crates/uv-build-backend/src/wheel.rs
index 34642a534..031756a3b 100644
--- a/crates/uv-build-backend/src/wheel.rs
+++ b/crates/uv-build-backend/src/wheel.rs
@@ -29,6 +29,7 @@ pub fn build_wheel(
     wheel_dir: &Path,
     metadata_directory: Option<&Path>,
     uv_version: &str,
+    show_warnings: bool,
 ) -> Result<WheelFilename, Error> {
     let contents = fs_err::read_to_string(source_tree.join("pyproject.toml"))?;
     let pyproject_toml = PyProjectToml::parse(&contents)?;
@@ -58,6 +59,7 @@ pub fn build_wheel(
         &filename,
         uv_version,
         wheel_writer,
+        show_warnings,
     )?;
 
     Ok(filename)
@@ -67,6 +69,7 @@ pub fn build_wheel(
 pub fn list_wheel(
     source_tree: &Path,
     uv_version: &str,
+    show_warnings: bool,
 ) -> Result<(WheelFilename, FileList), Error> {
     let contents = fs_err::read_to_string(source_tree.join("pyproject.toml"))?;
     let pyproject_toml = PyProjectToml::parse(&contents)?;
@@ -87,7 +90,14 @@ pub fn list_wheel(
 
     let mut files = FileList::new();
     let writer = ListWriter::new(&mut files);
-    write_wheel(source_tree, &pyproject_toml, &filename, uv_version, writer)?;
+    write_wheel(
+        source_tree,
+        &pyproject_toml,
+        &filename,
+        uv_version,
+        writer,
+        show_warnings,
+    )?;
     Ok((filename, files))
 }
 
@@ -97,6 +107,7 @@ fn write_wheel(
     filename: &WheelFilename,
     uv_version: &str,
     mut wheel_writer: impl DirectoryWriter,
+    show_warnings: bool,
 ) -> Result<(), Error> {
     let settings = pyproject_toml
         .settings()
@@ -132,6 +143,7 @@ fn write_wheel(
         &settings.module_root,
         settings.module_name.as_ref(),
         settings.namespace,
+        show_warnings,
     )?;
 
     let mut files_visited = 0;
@@ -259,6 +271,7 @@ pub fn build_editable(
     wheel_dir: &Path,
     metadata_directory: Option<&Path>,
     uv_version: &str,
+    show_warnings: bool,
 ) -> Result<WheelFilename, Error> {
     let contents = fs_err::read_to_string(source_tree.join("pyproject.toml"))?;
     let pyproject_toml = PyProjectToml::parse(&contents)?;
@@ -295,6 +308,7 @@ pub fn build_editable(
         &settings.module_root,
         settings.module_name.as_ref(),
         settings.namespace,
+        show_warnings,
     )?;
 
     wheel_writer.write_bytes(
diff --git a/crates/uv-build/src/main.rs b/crates/uv-build/src/main.rs
index 5dd2ce160..b3211cb4c 100644
--- a/crates/uv-build/src/main.rs
+++ b/crates/uv-build/src/main.rs
@@ -44,6 +44,7 @@ fn main() -> Result<()> {
                 &env::current_dir()?,
                 &sdist_directory,
                 uv_version::version(),
+                false,
             )?;
             // Tell the build frontend about the name of the artifact we built
             writeln!(&mut std::io::stdout(), "{filename}").context("stdout is closed")?;
@@ -56,6 +57,7 @@ fn main() -> Result<()> {
                 &wheel_directory,
                 metadata_directory.as_deref(),
                 uv_version::version(),
+                false,
             )?;
             // Tell the build frontend about the name of the artifact we built
             writeln!(&mut std::io::stdout(), "{filename}").context("stdout is closed")?;
@@ -68,6 +70,7 @@ fn main() -> Result<()> {
                 &wheel_directory,
                 metadata_directory.as_deref(),
                 uv_version::version(),
+                false,
             )?;
             // Tell the build frontend about the name of the artifact we built
             writeln!(&mut std::io::stdout(), "{filename}").context("stdout is closed")?;
diff --git a/crates/uv-dispatch/src/lib.rs b/crates/uv-dispatch/src/lib.rs
index 1b8570bab..f148e6dd2 100644
--- a/crates/uv-dispatch/src/lib.rs
+++ b/crates/uv-dispatch/src/lib.rs
@@ -504,6 +504,7 @@ impl BuildContext for BuildDispatch<'_> {
         source: &'data Path,
         subdirectory: Option<&'data Path>,
         output_dir: &'data Path,
+        sources: SourceStrategy,
         build_kind: BuildKind,
         version_id: Option<&'data str>,
     ) -> Result<Option<DistFilename>, BuildDispatchError> {
@@ -532,6 +533,7 @@ impl BuildContext for BuildDispatch<'_> {
                         &output_dir,
                         None,
                         uv_version::version(),
+                        sources == SourceStrategy::Enabled,
                     )?;
                     DistFilename::WheelFilename(wheel)
                 }
@@ -540,6 +542,7 @@ impl BuildContext for BuildDispatch<'_> {
                         &source_tree,
                         &output_dir,
                         uv_version::version(),
+                        sources == SourceStrategy::Enabled,
                     )?;
                     DistFilename::SourceDistFilename(source_dist)
                 }
@@ -549,6 +552,7 @@ impl BuildContext for BuildDispatch<'_> {
                         &output_dir,
                         None,
                         uv_version::version(),
+                        sources == SourceStrategy::Enabled,
                     )?;
                     DistFilename::WheelFilename(wheel)
                 }
diff --git a/crates/uv-distribution/src/source/mod.rs b/crates/uv-distribution/src/source/mod.rs
index d934d2b9f..e2ca8b46e 100644
--- a/crates/uv-distribution/src/source/mod.rs
+++ b/crates/uv-distribution/src/source/mod.rs
@@ -2435,6 +2435,7 @@ impl<'a, T: BuildContext> SourceDistributionBuilder<'a, T> {
                 source_root,
                 subdirectory,
                 temp_dir.path(),
+                source_strategy,
                 if source.is_editable() {
                     BuildKind::Editable
                 } else {
diff --git a/crates/uv-types/src/traits.rs b/crates/uv-types/src/traits.rs
index 6054ba302..a591691e0 100644
--- a/crates/uv-types/src/traits.rs
+++ b/crates/uv-types/src/traits.rs
@@ -158,6 +158,7 @@ pub trait BuildContext {
         source: &'a Path,
         subdirectory: Option<&'a Path>,
         output_dir: &'a Path,
+        sources: SourceStrategy,
         build_kind: BuildKind,
         version_id: Option<&'a str>,
     ) -> impl Future<Output = Result<Option<DistFilename>, impl IsBuildBackendError>> + 'a;
diff --git a/crates/uv/src/commands/build_backend.rs b/crates/uv/src/commands/build_backend.rs
index 2a725e149..c9f4e2ed5 100644
--- a/crates/uv/src/commands/build_backend.rs
+++ b/crates/uv/src/commands/build_backend.rs
@@ -10,6 +10,7 @@ pub(crate) fn build_sdist(sdist_directory: &Path) -> Result<ExitStatus> {
         &env::current_dir()?,
         sdist_directory,
         uv_version::version(),
+        false,
     )?;
     // Tell the build frontend about the name of the artifact we built
     writeln!(&mut std::io::stdout(), "{filename}").context("stdout is closed")?;
@@ -26,6 +27,7 @@ pub(crate) fn build_wheel(
         wheel_directory,
         metadata_directory,
         uv_version::version(),
+        false,
     )?;
     // Tell the build frontend about the name of the artifact we built
     writeln!(&mut std::io::stdout(), "{filename}").context("stdout is closed")?;
@@ -42,6 +44,7 @@ pub(crate) fn build_editable(
         wheel_directory,
         metadata_directory,
         uv_version::version(),
+        false,
     )?;
     // Tell the build frontend about the name of the artifact we built
     writeln!(&mut std::io::stdout(), "{filename}").context("stdout is closed")?;
diff --git a/crates/uv/src/commands/build_frontend.rs b/crates/uv/src/commands/build_frontend.rs
index eb4bd48d4..e19f51957 100644
--- a/crates/uv/src/commands/build_frontend.rs
+++ b/crates/uv/src/commands/build_frontend.rs
@@ -908,7 +908,11 @@ async fn build_sdist(
         BuildAction::List => {
             let source_tree_ = source_tree.to_path_buf();
             let (filename, file_list) = tokio::task::spawn_blocking(move || {
-                uv_build_backend::list_source_dist(&source_tree_, uv_version::version())
+                uv_build_backend::list_source_dist(
+                    &source_tree_,
+                    uv_version::version(),
+                    sources == SourceStrategy::Enabled,
+                )
             })
             .await??;
             let raw_filename = filename.to_string();
@@ -937,6 +941,7 @@ async fn build_sdist(
                     &source_tree,
                     &output_dir_,
                     uv_version::version(),
+                    sources == SourceStrategy::Enabled,
                 )
             })
             .await??
@@ -1013,7 +1018,11 @@ async fn build_wheel(
         BuildAction::List => {
             let source_tree_ = source_tree.to_path_buf();
             let (filename, file_list) = tokio::task::spawn_blocking(move || {
-                uv_build_backend::list_wheel(&source_tree_, uv_version::version())
+                uv_build_backend::list_wheel(
+                    &source_tree_,
+                    uv_version::version(),
+                    sources == SourceStrategy::Enabled,
+                )
             })
             .await??;
             let raw_filename = filename.to_string();
@@ -1043,6 +1052,7 @@ async fn build_wheel(
                     &output_dir_,
                     None,
                     uv_version::version(),
+                    sources == SourceStrategy::Enabled,
                 )
             })
             .await??;
diff --git a/crates/uv/tests/it/build_backend.rs b/crates/uv/tests/it/build_backend.rs
index 4572069b5..608eaadbb 100644
--- a/crates/uv/tests/it/build_backend.rs
+++ b/crates/uv/tests/it/build_backend.rs
@@ -1117,3 +1117,71 @@ fn venv_in_source_tree() {
       ╰─▶ Virtual environments must not be added to source distributions or wheels, remove the directory or exclude it from the build: src/foo/.venv
     ");
 }
+
+/// Show a warning when the build backend is passed redundant module names
+#[test]
+fn warn_on_redundant_module_names() -> Result<()> {
+    let context = TestContext::new("3.12");
+
+    let pyproject_toml = context.temp_dir.child("pyproject.toml");
+    pyproject_toml.write_str(indoc! {r#"
+        [project]
+        name = "project"
+        version = "0.1.0"
+        requires-python = ">=3.12"
+
+        [build-system]
+        requires = ["uv_build>=0.7,<10000"]
+        build-backend = "uv_build"
+
+        [tool.uv.build-backend]
+        module-name = ["foo", "foo.bar", "foo", "foo.bar.baz", "foobar", "bar", "foobar.baz", "baz.bar"]
+    "#})?;
+
+    let foo_module = context.temp_dir.child("src/foo");
+    foo_module.create_dir_all()?;
+    foo_module.child("__init__.py").touch()?;
+
+    let foobar_module = context.temp_dir.child("src/foobar");
+    foobar_module.create_dir_all()?;
+    foobar_module.child("__init__.py").touch()?;
+
+    let bazbar_module = context.temp_dir.child("src/baz/bar");
+    bazbar_module.create_dir_all()?;
+    bazbar_module.child("__init__.py").touch()?;
+
+    let bar_module = context.temp_dir.child("src/bar");
+    bar_module.create_dir_all()?;
+    bar_module.child("__init__.py").touch()?;
+
+    // Warnings should be printed when invoking `uv build`
+    uv_snapshot!(context.filters(), context.build(), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Building source distribution (uv build backend)...
+    warning: Ignoring redundant module names in `tool.uv.build-backend.module-name`: `foo.bar`, `foo`, `foo.bar.baz`, `foobar.baz`
+    Building wheel from source distribution (uv build backend)...
+    Successfully built dist/project-0.1.0.tar.gz
+    Successfully built dist/project-0.1.0-py3-none-any.whl
+    ");
+
+    // But warnings shouldn't be printed in cases when the user might not
+    // control the thing being built. Sources being enabled is a workable proxy
+    // for this.
+    uv_snapshot!(context.filters(), context.build().arg("--no-sources"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Building source distribution (uv build backend)...
+    Building wheel from source distribution (uv build backend)...
+    Successfully built dist/project-0.1.0.tar.gz
+    Successfully built dist/project-0.1.0-py3-none-any.whl
+    ");
+
+    Ok(())
+}