Add script sources support

crates/uv-dispatch/src/lib.rs

@@ -22,6 +22,7 @@ use uv_configuration::{
 };
 use uv_configuration::{BuildOutput, Concurrency};
 use uv_distribution::DistributionDatabase;
+use uv_distribution::ExtraBuildRequires;
 use uv_distribution_filename::DistFilename;
 use uv_distribution_types::{
     CachedDist, DependencyMetadata, Identifier, IndexCapabilities, IndexLocations,
@@ -40,7 +41,6 @@ use uv_types::{
     HashStrategy, InFlight,
 };
 use uv_workspace::WorkspaceCache;
-use uv_distribution::ExtraBuildRequires;
 
 #[derive(Debug, Error)]
 pub enum BuildDispatchError {

crates/uv-distribution/src/metadata/build_requires.rs

@@ -261,13 +261,15 @@ impl ExtraBuildRequires {
                                 workspace,
                                 None,
                             )
-                            .map(move |requirement| match requirement {
-                                Ok(requirement) => Ok(requirement.into_inner().into()),
-                                Err(err) => Err(MetadataError::LoweringError(
-                                    requirement_name.clone(),
-                                    Box::new(err),
-                                )),
-                            })
+                            .map(
+                                move |requirement| match requirement {
+                                    Ok(requirement) => Ok(requirement.into_inner().into()),
+                                    Err(err) => Err(MetadataError::LoweringError(
+                                        requirement_name.clone(),
+                                        Box::new(err),
+                                    )),
+                                },
+                            )
                         })
                         .collect::<Result<Vec<_>, _>>()?;
                     result.insert(package_name, lowered);

crates/uv-scripts/src/lib.rs

@@ -381,6 +381,8 @@ pub struct ToolUv {
     pub override_dependencies: Option<Vec<uv_pep508::Requirement<VerbatimParsedUrl>>>,
     pub constraint_dependencies: Option<Vec<uv_pep508::Requirement<VerbatimParsedUrl>>>,
     pub build_constraint_dependencies: Option<Vec<uv_pep508::Requirement<VerbatimParsedUrl>>>,
+    pub extra_build_dependencies:
+        Option<BTreeMap<PackageName, Vec<uv_pep508::Requirement<VerbatimParsedUrl>>>>,
     pub sources: Option<BTreeMap<PackageName, Sources>>,
 }
 

crates/uv/src/commands/build_frontend.rs

@@ -564,9 +564,8 @@ async fn build_package(
     let workspace_cache = WorkspaceCache::default();
 
     // Create a build dispatch.
-    let extra_build_requires = uv_distribution::ExtraBuildRequires::from_lowered(
-        extra_build_dependencies.clone(),
-    );
+    let extra_build_requires =
+        uv_distribution::ExtraBuildRequires::from_lowered(extra_build_dependencies.clone());
     let build_dispatch = BuildDispatch::new(
         &client,
         cache,

crates/uv/src/commands/pip/compile.rs

@@ -477,9 +477,8 @@ pub(crate) async fn pip_compile(
             .map(|constraint| constraint.requirement.clone()),
     );
 
-    let extra_build_requires = uv_distribution::ExtraBuildRequires::from_lowered(
-        extra_build_dependencies.clone(),
-    );
+    let extra_build_requires =
+        uv_distribution::ExtraBuildRequires::from_lowered(extra_build_dependencies.clone());
     let build_dispatch = BuildDispatch::new(
         &client,
         &cache,

crates/uv/src/commands/pip/install.rs

@@ -420,9 +420,8 @@ pub(crate) async fn pip_install(
     let state = SharedState::default();
 
     // Create a build dispatch.
-    let extra_build_requires = uv_distribution::ExtraBuildRequires::from_lowered(
-        extra_build_dependencies.clone(),
-    );
+    let extra_build_requires =
+        uv_distribution::ExtraBuildRequires::from_lowered(extra_build_dependencies.clone());
     let build_dispatch = BuildDispatch::new(
         &client,
         &cache,

crates/uv/src/commands/pip/sync.rs

@@ -355,9 +355,8 @@ pub(crate) async fn pip_sync(
     let state = SharedState::default();
 
     // Create a build dispatch.
-    let extra_build_requires = uv_distribution::ExtraBuildRequires::from_lowered(
-        extra_build_dependencies.clone(),
-    );
+    let extra_build_requires =
+        uv_distribution::ExtraBuildRequires::from_lowered(extra_build_dependencies.clone());
     let build_dispatch = BuildDispatch::new(
         &client,
         &cache,

crates/uv/src/commands/project/add.rs

@@ -1298,6 +1298,7 @@ impl PythonTarget {
 
 /// Represents the destination where dependencies are added, either to a project or a script.
 #[derive(Debug, Clone)]
+#[allow(clippy::large_enum_variant)]
 pub(super) enum AddTarget {
     /// A PEP 723 script, with inline metadata.
     Script(Pep723Script, Box<Interpreter>),
@@ -1398,6 +1399,7 @@ impl AddTarget {
 }
 
 #[derive(Debug, Clone)]
+#[allow(clippy::large_enum_variant)]
 enum AddTargetSnapshot {
     Script(Pep723Script, Option<Vec<u8>>),
     Project(VirtualProject, Option<Vec<u8>>),

crates/uv/src/commands/project/export.rs

@@ -32,6 +32,7 @@ use crate::printer::Printer;
 use crate::settings::{NetworkSettings, ResolverSettings};
 
 #[derive(Debug, Clone)]
+#[allow(clippy::large_enum_variant)]
 enum ExportTarget {
     /// A PEP 723 script, with inline metadata.
     Script(Pep723Script),

crates/uv/src/commands/project/lock.rs

@@ -42,7 +42,7 @@ use crate::commands::pip::loggers::{DefaultResolveLogger, ResolveLogger, Summary
 use crate::commands::project::lock_target::LockTarget;
 use crate::commands::project::{
     ProjectError, ProjectInterpreter, ScriptInterpreter, UniversalState,
-    init_script_python_requirement,
+    init_script_python_requirement, script_specification,
 };
 use crate::commands::reporters::{PythonDownloadReporter, ResolverReporter};
 use crate::commands::{ExitStatus, ScriptPath, diagnostics, pip};
@@ -678,9 +678,16 @@ async fn do_lock(
             index_locations,
             *sources,
         )?,
-        LockTarget::Script(_) => uv_distribution::ExtraBuildRequires::from_lowered(
-            extra_build_dependencies.clone(),
-        ),
+        LockTarget::Script(script) => {
+            // Try to get extra build dependencies from the script metadata
+            script_specification(Pep723ItemRef::Script(script), settings)?
+                .map(|spec| spec.extra_build_requires)
+                .unwrap_or_else(|| {
+                    uv_distribution::ExtraBuildRequires::from_lowered(
+                        extra_build_dependencies.clone(),
+                    )
+                })
+        }
     };
     let build_dispatch = BuildDispatch::new(
         &client,

crates/uv/src/commands/project/mod.rs

@@ -46,6 +46,7 @@ use uv_types::{BuildIsolation, EmptyInstalledPackages, HashStrategy};
 use uv_virtualenv::remove_virtualenv;
 use uv_warnings::{warn_user, warn_user_once};
 use uv_workspace::dependency_groups::DependencyGroupError;
+use uv_workspace::pyproject::ExtraBuildDependencies;
 use uv_workspace::pyproject::PyProjectToml;
 use uv_workspace::{RequiresPythonSources, Workspace, WorkspaceCache};
 
@@ -1741,9 +1742,8 @@ pub(crate) async fn resolve_names(
     let build_hasher = HashStrategy::default();
 
     // Create a build dispatch.
-    let extra_build_requires = uv_distribution::ExtraBuildRequires::from_lowered(
-        extra_build_dependencies.clone(),
-    );
+    let extra_build_requires =
+        uv_distribution::ExtraBuildRequires::from_lowered(extra_build_dependencies.clone());
     let build_dispatch = BuildDispatch::new(
         &client,
         cache,
@@ -1954,9 +1954,8 @@ pub(crate) async fn resolve_environment(
     let workspace_cache = WorkspaceCache::default();
 
     // Create a build dispatch.
-    let extra_build_requires = uv_distribution::ExtraBuildRequires::from_lowered(
-        extra_build_dependencies.clone(),
-    );
+    let extra_build_requires =
+        uv_distribution::ExtraBuildRequires::from_lowered(extra_build_dependencies.clone());
     let resolve_dispatch = BuildDispatch::new(
         &client,
         cache,
@@ -2097,9 +2096,8 @@ pub(crate) async fn sync_environment(
     };
 
     // Create a build dispatch.
-    let extra_build_requires = uv_distribution::ExtraBuildRequires::from_lowered(
-        extra_build_dependencies.clone(),
-    );
+    let extra_build_requires =
+        uv_distribution::ExtraBuildRequires::from_lowered(extra_build_dependencies.clone());
     let build_dispatch = BuildDispatch::new(
         &client,
         cache,
@@ -2157,6 +2155,15 @@ pub(crate) async fn sync_environment(
     Ok(venv)
 }
 
+/// A script specification that includes both requirements and extra build dependencies.
+#[derive(Debug)]
+pub(crate) struct ScriptSpecification {
+    /// The requirements specification for the script.
+    pub(crate) requirements: RequirementsSpecification,
+    /// The extra build dependencies for the script.
+    pub(crate) extra_build_requires: uv_distribution::ExtraBuildRequires,
+}
+
 /// The result of updating a [`PythonEnvironment`] to satisfy a set of [`RequirementsSource`]s.
 #[derive(Debug)]
 pub(crate) struct EnvironmentUpdate {
@@ -2179,6 +2186,7 @@ pub(crate) async fn update_environment(
     spec: RequirementsSpecification,
     modifications: Modifications,
     build_constraints: Constraints,
+    extra_build_requires: uv_distribution::ExtraBuildRequires,
     settings: &ResolverInstallerSettings,
     network_settings: &NetworkSettings,
     state: &SharedState,
@@ -2209,7 +2217,7 @@ pub(crate) async fn update_environment(
                 link_mode,
                 no_build_isolation,
                 no_build_isolation_package,
-                extra_build_dependencies,
+                extra_build_dependencies: _,
                 prerelease,
                 resolution,
                 sources,
@@ -2326,9 +2334,6 @@ pub(crate) async fn update_environment(
     };
 
     // Create a build dispatch.
-    let extra_build_requires = uv_distribution::ExtraBuildRequires::from_lowered(
-        extra_build_dependencies.clone(),
-    );
     let build_dispatch = BuildDispatch::new(
         &client,
         cache,
@@ -2547,12 +2552,12 @@ pub(crate) fn detect_conflicts(
     Ok(())
 }
 
-/// Determine the [`RequirementsSpecification`] for a script.
+/// Determine the [`ScriptSpecification`] for a script.
 #[allow(clippy::result_large_err)]
 pub(crate) fn script_specification(
     script: Pep723ItemRef<'_>,
     settings: &ResolverSettings,
-) -> Result<Option<RequirementsSpecification>, ProjectError> {
+) -> Result<Option<ScriptSpecification>, ProjectError> {
     let Some(dependencies) = script.metadata().dependencies.as_ref() else {
         return Ok(None);
     };
@@ -2647,11 +2652,47 @@ pub(crate) fn script_specification(
         })
         .collect::<Result<Vec<_>, _>>()?;
 
-    Ok(Some(RequirementsSpecification::from_overrides(
-        requirements,
-        constraints,
-        overrides,
-    )))
+    // Collect any `tool.uv.extra-build-dependencies` from the script.
+    let empty = BTreeMap::default();
+    let script_extra_build_dependencies = script
+        .metadata()
+        .tool
+        .as_ref()
+        .and_then(|tool| tool.uv.as_ref())
+        .and_then(|uv| uv.extra_build_dependencies.as_ref())
+        .unwrap_or(&empty);
+
+    // Lower the extra build dependencies
+    let mut extra_build_dependencies = ExtraBuildDependencies::default();
+    for (name, requirements) in script_extra_build_dependencies {
+        let lowered_requirements: Vec<_> = requirements
+            .iter()
+            .cloned()
+            .flat_map(|requirement| {
+                LoweredRequirement::from_non_workspace_requirement(
+                    requirement,
+                    script_dir.as_ref(),
+                    script_sources,
+                    script_indexes,
+                    &settings.index_locations,
+                )
+                .map_ok(|req| req.into_inner().into())
+            })
+            .collect::<Result<Vec<_>, _>>()?;
+        extra_build_dependencies.insert(name.clone(), lowered_requirements);
+    }
+
+    let extra_build_requires =
+        uv_distribution::ExtraBuildRequires::from_lowered(extra_build_dependencies);
+
+    Ok(Some(ScriptSpecification {
+        requirements: RequirementsSpecification::from_overrides(
+            requirements,
+            constraints,
+            overrides,
+        ),
+        extra_build_requires,
+    }))
 }
 
 /// Warn if the user provides (e.g.) an `--index-url` in a requirements file.

crates/uv/src/commands/project/remove.rs

@@ -386,6 +386,7 @@ pub(crate) async fn remove(
 
 /// Represents the destination where dependencies are added, either to a project or a script.
 #[derive(Debug)]
+#[allow(clippy::large_enum_variant)]
 enum RemoveTarget {
     /// A PEP 723 script, with inline metadata.
     Project(VirtualProject),

crates/uv/src/commands/project/run.rs

@@ -358,7 +358,9 @@ hint: If you are running a script with `{}` in the shebang, you may need to incl
             }
 
             // Install the script requirements, if necessary. Otherwise, use an isolated environment.
-            if let Some(spec) = script_specification((&script).into(), &settings.resolver)? {
+            if let Some(script_spec) = script_specification((&script).into(), &settings.resolver)? {
+                let spec = script_spec.requirements;
+                let script_extra_build_requires = script_spec.extra_build_requires;
                 let environment = ScriptEnvironment::get_or_init(
                     (&script).into(),
                     python.as_deref().map(PythonRequest::parse),
@@ -407,6 +409,7 @@ hint: If you are running a script with `{}` in the shebang, you may need to incl
                     spec,
                     modifications,
                     build_constraints.unwrap_or_default(),
+                    script_extra_build_requires,
                     &settings,
                     &network_settings,
                     &sync_state,

crates/uv/src/commands/project/sync.rs

@@ -14,12 +14,11 @@ use uv_client::{BaseClientBuilder, FlatIndexClient, RegistryClientBuilder};
 use uv_configuration::{
     Concurrency, Constraints, DependencyGroups, DependencyGroupsWithDefaults, DryRun, EditableMode,
     ExtrasSpecification, ExtrasSpecificationWithDefaults, HashCheckingMode, InstallOptions,
-    PreviewMode, TargetTriple,
+    PreviewMode, TargetTriple, Upgrade,
 };
 use uv_dispatch::BuildDispatch;
 use uv_distribution_types::{
-    DirectorySourceDist, Dist, Index, Requirement, Resolution, ResolvedDist,
-    SourceDist,
+    DirectorySourceDist, Dist, Index, Requirement, Resolution, ResolvedDist, SourceDist,
 };
 use uv_fs::{PortablePathBuf, Simplified};
 use uv_installer::SitePackages;
@@ -27,15 +26,14 @@ use uv_normalize::{DefaultExtras, DefaultGroups, PackageName};
 use uv_pep508::{MarkerTree, VersionOrUrl};
 use uv_pypi_types::{ParsedArchiveUrl, ParsedGitUrl, ParsedUrl};
 use uv_python::{PythonDownloads, PythonEnvironment, PythonPreference, PythonRequest};
-use uv_resolver::{FlatIndex, Installable, Lock};
+use uv_requirements::RequirementsSpecification;
+use uv_resolver::{FlatIndex, ForkStrategy, Installable, Lock, PrereleaseMode, ResolutionMode};
 use uv_scripts::{Pep723ItemRef, Pep723Script};
 use uv_settings::PythonInstallMirrors;
 use uv_types::{BuildIsolation, HashStrategy};
 use uv_warnings::{warn_user, warn_user_once};
 use uv_workspace::pyproject::{ExtraBuildDependencies, Source};
-use uv_workspace::{
-    DiscoveryOptions, MemberDiscovery, VirtualProject, Workspace, WorkspaceCache,
-};
+use uv_workspace::{DiscoveryOptions, MemberDiscovery, VirtualProject, Workspace, WorkspaceCache};
 
 use crate::commands::pip::loggers::{DefaultInstallLogger, DefaultResolveLogger, InstallLogger};
 use crate::commands::pip::operations::Modifications;
@@ -50,7 +48,9 @@ use crate::commands::project::{
 };
 use crate::commands::{ExitStatus, diagnostics};
 use crate::printer::Printer;
-use crate::settings::{InstallerSettingsRef, NetworkSettings, ResolverInstallerSettings};
+use crate::settings::{
+    InstallerSettingsRef, NetworkSettings, ResolverInstallerSettings, ResolverSettings,
+};
 
 /// Sync the project environment.
 #[allow(clippy::fn_params_excessive_bools)]
@@ -223,8 +223,18 @@ pub(crate) async fn sync(
             }
 
             // Parse the requirements from the script.
-            let spec = script_specification(Pep723ItemRef::Script(script), &settings.resolver)?
-                .unwrap_or_default();
+            let script_spec =
+                script_specification(Pep723ItemRef::Script(script), &settings.resolver)?;
+            let (spec, script_extra_build_requires) = if let Some(script_spec) = script_spec {
+                (script_spec.requirements, script_spec.extra_build_requires)
+            } else {
+                (
+                    RequirementsSpecification::default(),
+                    uv_distribution::ExtraBuildRequires::from_lowered(
+                        ExtraBuildDependencies::default(),
+                    ),
+                )
+            };
 
             // Parse the build constraints from the script.
             let build_constraints = script
@@ -249,6 +259,7 @@ pub(crate) async fn sync(
                 spec,
                 modifications,
                 build_constraints.unwrap_or_default(),
+                script_extra_build_requires,
                 &settings,
                 &network_settings,
                 &PlatformState::default(),
@@ -495,6 +506,7 @@ fn identify_installation_target<'a>(
 }
 
 #[derive(Debug, Clone)]
+#[allow(clippy::large_enum_variant)]
 enum SyncTarget {
     /// Sync a project environment.
     Project(VirtualProject),
@@ -546,7 +558,6 @@ impl Deref for SyncEnvironment {
     }
 }
 
-
 /// Sync a lockfile with an environment.
 #[allow(clippy::fn_params_excessive_bools)]
 pub(super) async fn do_sync(
@@ -607,12 +618,35 @@ pub(super) async fn do_sync(
                 sources,
             )?
         }
-        InstallTarget::Script { .. } => uv_distribution::ExtraBuildRequires {
-            extra_build_dependencies: ExtraBuildDependencies::default(),
-        },
+        InstallTarget::Script { script, .. } => {
+            // Try to get extra build dependencies from the script metadata
+            let resolver_settings = ResolverSettings {
+                build_options: build_options.clone(),
+                config_setting: config_setting.clone(),
+                config_settings_package: config_settings_package.clone(),
+                dependency_metadata: dependency_metadata.clone(),
+                exclude_newer,
+                fork_strategy: ForkStrategy::default(),
+                index_locations: index_locations.clone(),
+                index_strategy,
+                keyring_provider,
+                link_mode,
+                no_build_isolation,
+                no_build_isolation_package: no_build_isolation_package.to_vec(),
+                extra_build_dependencies: extra_build_dependencies.clone(),
+                prerelease: PrereleaseMode::default(),
+                resolution: ResolutionMode::default(),
+                sources,
+                upgrade: Upgrade::default(),
+            };
+            script_specification(Pep723ItemRef::Script(script), &resolver_settings)?
+                .map(|spec| spec.extra_build_requires)
+                .unwrap_or_else(|| uv_distribution::ExtraBuildRequires {
+                    extra_build_dependencies: ExtraBuildDependencies::default(),
+                })
+        }
     };
 
-
     let client_builder = BaseClientBuilder::new()
         .retries_from_env()?
         .connectivity(network_settings.connectivity)

crates/uv/src/commands/tool/install.rs

@@ -23,7 +23,7 @@ use uv_requirements::{RequirementsSource, RequirementsSpecification};
 use uv_settings::{PythonInstallMirrors, ResolverInstallerOptions, ToolOptions};
 use uv_tool::InstalledTools;
 use uv_warnings::warn_user;
-use uv_workspace::WorkspaceCache;
+use uv_workspace::{WorkspaceCache, pyproject::ExtraBuildDependencies};
 
 use crate::commands::ExitStatus;
 use crate::commands::pip::loggers::{DefaultInstallLogger, DefaultResolveLogger};
@@ -439,6 +439,7 @@ pub(crate) async fn install(
             spec,
             Modifications::Exact,
             Constraints::from_requirements(build_constraints.iter().cloned()),
+            uv_distribution::ExtraBuildRequires::from_lowered(ExtraBuildDependencies::default()),
             &settings,
             &network_settings,
             &state,

crates/uv/src/commands/tool/upgrade.rs

@@ -18,7 +18,7 @@ use uv_python::{
 use uv_requirements::RequirementsSpecification;
 use uv_settings::{Combine, PythonInstallMirrors, ResolverInstallerOptions, ToolOptions};
 use uv_tool::InstalledTools;
-use uv_workspace::WorkspaceCache;
+use uv_workspace::{WorkspaceCache, pyproject::ExtraBuildDependencies};
 
 use crate::commands::pip::loggers::{
     DefaultInstallLogger, SummaryResolveLogger, UpgradeInstallLogger,
@@ -343,6 +343,7 @@ async fn upgrade_tool(
             spec,
             Modifications::Exact,
             build_constraints,
+            uv_distribution::ExtraBuildRequires::from_lowered(ExtraBuildDependencies::default()),
             &settings,
             network_settings,
             &state,

crates/uv/src/commands/venv.rs

@@ -275,9 +275,8 @@ pub(crate) async fn venv(
 
         // Do not allow builds
         let build_options = BuildOptions::new(NoBinary::None, NoBuild::All);
-        let extra_build_requires = uv_distribution::ExtraBuildRequires::from_lowered(
-            ExtraBuildDependencies::default(),
-        );
+        let extra_build_requires =
+            uv_distribution::ExtraBuildRequires::from_lowered(ExtraBuildDependencies::default());
         // Prep the build context.
         let build_dispatch = BuildDispatch::new(
             &client,

crates/uv/tests/it/show_settings.rs

@@ -3931,6 +3931,7 @@ fn resolve_both_special_fields() -> anyhow::Result<()> {
             torch_backend: None,
             no_build_isolation: false,
             no_build_isolation_package: [],
+            extra_build_dependencies: {},
             build_options: BuildOptions {
                 no_binary: None,
                 no_build: None,

crates/uv/tests/it/sync.rs

@@ -1778,7 +1778,7 @@ fn sync_extra_build_dependencies() -> Result<()> {
         [tool.uv.sources]
         child = { path = "child" }
         bad_child = { path = "bad_child" }
-        
+
         [tool.uv.extra-build-dependencies]
         child = ["anyio"]
     "#})?;
@@ -1833,7 +1833,7 @@ fn sync_extra_build_dependencies_sources() -> Result<()> {
         except ModuleNotFoundError:
             print("Missing `anyio` module", file=sys.stderr)
             sys.exit(1)
-        
+
         # Check that we got the local version of anyio by checking for the marker
         if not hasattr(anyio, 'LOCAL_ANYIO_MARKER'):
             print("Found system anyio instead of local anyio", file=sys.stderr)
@@ -1915,7 +1915,7 @@ fn sync_extra_build_dependencies_sources_from_child() -> Result<()> {
         except ModuleNotFoundError:
             print("Missing `anyio` module", file=sys.stderr)
             sys.exit(1)
-        
+
         # Check that we got the local version of anyio by checking for the marker
         if not hasattr(anyio, 'LOCAL_ANYIO_MARKER'):
             print("Found system anyio instead of local anyio", file=sys.stderr)
@@ -4593,6 +4593,187 @@ fn no_install_project_no_build() -> Result<()> {
     Ok(())
 }
 
+#[test]
+fn sync_extra_build_dependencies_script() -> Result<()> {
+    let context = TestContext::new("3.12").with_filtered_counts();
+
+    // Write a test package that arbitrarily requires `anyio` at build time
+    let child = context.temp_dir.child("child");
+    child.create_dir_all()?;
+    let child_pyproject_toml = child.child("pyproject.toml");
+    child_pyproject_toml.write_str(indoc! {r#"
+        [project]
+        name = "child"
+        version = "0.1.0"
+        requires-python = ">=3.9"
+        [build-system]
+        requires = ["hatchling"]
+        backend-path = ["."]
+        build-backend = "build_backend"
+    "#})?;
+    let build_backend = child.child("build_backend.py");
+    build_backend.write_str(indoc! {r#"
+        import sys
+        from hatchling.build import *
+        try:
+            import anyio
+        except ModuleNotFoundError:
+            print("Missing `anyio` module", file=sys.stderr)
+            sys.exit(1)
+    "#})?;
+    child.child("src/child/__init__.py").touch()?;
+
+    // Create a script that depends on the child package
+    let script = context.temp_dir.child("script.py");
+    script.write_str(indoc! {r#"
+        # /// script
+        # requires-python = ">=3.12"
+        # dependencies = ["child"]
+        #
+        # [tool.uv.sources]
+        # child = { path = "child" }
+        # ///
+    "#})?;
+
+    let filters = context
+        .filters()
+        .into_iter()
+        .chain(vec![(
+            r"environments-v2/script-[a-z0-9]+",
+            "environments-v2/script-[HASH]",
+        )])
+        .collect::<Vec<_>>();
+
+    // Running `uv sync` should fail due to missing build-dependencies
+    uv_snapshot!(filters, context.sync().arg("--script").arg("script.py"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+
+    ----- stderr -----
+    Creating script environment at: [CACHE_DIR]/environments-v2/script-[HASH]
+    Resolved [N] packages in [TIME]
+      × Failed to build `child @ file://[TEMP_DIR]/child`
+      ├─▶ The build backend returned an error
+      ╰─▶ Call to `build_backend.build_wheel` failed (exit status: 1)
+
+          [stderr]
+          Missing `anyio` module
+
+          hint: This usually indicates a problem with the package or the build environment.
+    ");
+
+    // Add extra build dependencies to the script
+    script.write_str(indoc! {r#"
+        # /// script
+        # requires-python = ">=3.12"
+        # dependencies = ["child"]
+        #
+        # [tool.uv.sources]
+        # child = { path = "child" }
+        #
+        # [tool.uv.extra-build-dependencies]
+        # child = ["anyio"]
+        # ///
+    "#})?;
+
+    // Running `uv sync` should now succeed due to extra build-dependencies
+    context.venv().arg("--clear").assert().success();
+    uv_snapshot!(filters, context.sync().arg("--script").arg("script.py"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Using script environment at: [CACHE_DIR]/environments-v2/script-[HASH]
+    Resolved [N] packages in [TIME]
+    Prepared [N] packages in [TIME]
+    Installed [N] packages in [TIME]
+     + child==0.1.0 (from file://[TEMP_DIR]/child)
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn sync_extra_build_dependencies_script_sources() -> Result<()> {
+    let context = TestContext::new("3.12").with_filtered_counts();
+    let anyio_local = context.workspace_root.join("scripts/packages/anyio_local");
+
+    // Write a test package that arbitrarily requires `anyio` at a specific _path_ at build time
+    let child = context.temp_dir.child("child");
+    child.create_dir_all()?;
+    let child_pyproject_toml = child.child("pyproject.toml");
+    child_pyproject_toml.write_str(indoc! {r#"
+        [project]
+        name = "child"
+        version = "0.1.0"
+        requires-python = ">=3.9"
+        [build-system]
+        requires = ["hatchling"]
+        backend-path = ["."]
+        build-backend = "build_backend"
+    "#})?;
+    let build_backend = child.child("build_backend.py");
+    build_backend.write_str(&formatdoc! {r#"
+        import sys
+        from hatchling.build import *
+        try:
+            import anyio
+        except ModuleNotFoundError:
+            print("Missing `anyio` module", file=sys.stderr)
+            sys.exit(1)
+
+        # Check that we got the local version of anyio by checking for the marker
+        if not hasattr(anyio, 'LOCAL_ANYIO_MARKER'):
+            print("Found system anyio instead of local anyio", file=sys.stderr)
+            sys.exit(1)
+    "#})?;
+    child.child("src/child/__init__.py").touch()?;
+
+    // Create a script that depends on the child package
+    let script = context.temp_dir.child("script.py");
+    script.write_str(&formatdoc! {r#"
+        # /// script
+        # requires-python = ">=3.12"
+        # dependencies = ["child"]
+        #
+        # [tool.uv.sources]
+        # anyio = {{ path = "{}" }}
+        # child = {{ path = "child" }}
+        #
+        # [tool.uv.extra-build-dependencies]
+        # child = ["anyio"]
+        # ///
+    "#, anyio_local.display()
+    })?;
+
+    let filters = context
+        .filters()
+        .into_iter()
+        .chain(vec![(
+            r"environments-v2/script-[a-z0-9]+",
+            "environments-v2/script-[HASH]",
+        )])
+        .collect::<Vec<_>>();
+
+    // Running `uv sync` should succeed with the sources applied
+    uv_snapshot!(filters, context.sync().arg("--script").arg("script.py"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Creating script environment at: [CACHE_DIR]/environments-v2/script-[HASH]
+    Resolved [N] packages in [TIME]
+    Prepared [N] packages in [TIME]
+    Installed [N] packages in [TIME]
+     + child==0.1.0 (from file://[TEMP_DIR]/child)
+    ");
+
+    Ok(())
+}
+
 #[test]
 fn virtual_no_build() -> Result<()> {
     let context = TestContext::new("3.12");