diff --git a/crates/ide-build/src/maven.rs b/crates/ide-build/src/maven.rs
index 0268adb63..346049bc4 100644
--- a/crates/ide-build/src/maven.rs
+++ b/crates/ide-build/src/maven.rs
@@ -71,6 +71,9 @@ pub struct MavenModel {
 #[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize, Type)]
 #[serde(rename_all = "camelCase")]
 pub struct MavenProject {
+    /// Owning project folder when displayed in a workspace.
+    #[specta(optional)]
+    pub project_root: Option<String>,
     /// Project-relative, `/`-separated (`pom.xml`, `core/pom.xml`).
     pub pom: String,
     /// Project-relative directory; `""` = the project root.
@@ -169,6 +172,9 @@ pub enum Omission {
 #[derive(Clone, Debug, Default, PartialEq, Eq, Serialize, Deserialize, Type)]
 #[serde(rename_all = "camelCase")]
 pub struct MavenProfile {
+    /// Owning project folder when displayed in a workspace.
+    #[specta(optional)]
+    pub project_root: Option<String>,
     pub id: String,
     pub active_by_default: bool,
 }
@@ -503,7 +509,7 @@ pub fn settings_profiles(settings: &Path) -> Vec<MavenProfile> {
             continue;
         }
         let by_default = profile.at("activation/activeByDefault").is_some_and(|e| e.text.trim() == "true");
-        profiles.push(MavenProfile { active_by_default: by_default || active.contains(&id), id });
+        profiles.push(MavenProfile { active_by_default: by_default || active.contains(&id), id, ..Default::default() });
     }
     profiles
 }
@@ -1212,11 +1218,12 @@ pub fn load_with_linked(
         // The project can activate the profiles of its own POM and its ancestors'.
         for (id, active) in &ctx.profiles {
             if !model.profiles.iter().any(|x| x.id == *id) {
-                model.profiles.push(MavenProfile { id: id.clone(), active_by_default: *active });
+                model.profiles.push(MavenProfile { id: id.clone(), active_by_default: *active, ..Default::default() });
             }
         }
         let artifact_id = i(&pom.artifact_id);
         model.projects.push(MavenProject {
+            project_root: None,
             pom: rel_path(root, &path),
             dir: rel_path(root, &dir),
             group_id: i(props.get("project.groupId").map(String::as_str).unwrap_or_default()),
@@ -1836,7 +1843,7 @@ mod tests {
 </settings>"#,
         )
         .unwrap();
-        let p = |id: &str, active| MavenProfile { id: id.into(), active_by_default: active };
+        let p = |id: &str, active| MavenProfile { id: id.into(), active_by_default: active, ..Default::default() };
         assert_eq!(settings_profiles(&file), [p("nexus", true), p("jdk21", true), p("release", false)]);
         assert!(settings_profiles(&tmp.path().join("missing.xml")).is_empty());
 
diff --git a/crates/ide-host/src/ops/build.rs b/crates/ide-host/src/ops/build.rs
index 7bcc9cc99..1fa72128e 100644
--- a/crates/ide-host/src/ops/build.rs
+++ b/crates/ide-host/src/ops/build.rs
@@ -1,5 +1,7 @@
 //! Maven / Gradle tool windows (the build model and its background sync) and
 //! Build › Build Project (compiling with the project's build system).
+mod workspace;
+
 use crate::ops::Channel;
 use crate::rpc::Dispatcher;
 use crate::{Host, Project, apply_workspace_edit};
@@ -10,7 +12,6 @@ use ide_build::pom_edit::{ArtifactKey, Exclusion};
 use ide_build::{BuildModel, BuildTool, SyncOptions, SyncProgress};
 use ide_core::settings::Settings;
 use ide_core::{FileEdit, IdeError, IdeEvent, IdeResult, Location, Pos, Range, RequestId, WorkspaceEdit};
-use std::collections::BTreeMap;
 use std::path::Path;
 
 fn join_err(e: tokio::task::JoinError) -> IdeError {
@@ -125,8 +126,8 @@ fn with_profiles(mut model: BuildModel, cache: &Path) -> BuildModel {
 pub async fn build_model(host: &Host, window: &str) -> IdeResult<BuildModel> {
     host.require_trust(window)?;
     let project = host.project(window)?;
-    let (root, cache, settings) = (project.root.clone(), project.build_cache_dir(), project.settings.effective());
-    tokio::task::spawn_blocking(move || load(&root, &cache, &settings)).await.map_err(join_err)
+    let config = host.config_dir.clone();
+    tokio::task::spawn_blocking(move || workspace::load_project(&project, &config)).await.map_err(join_err)?
 }
 
 fn linked_gradle_paths(
@@ -224,84 +225,89 @@ pub async fn build_sync(
 ) -> IdeResult<BuildModel> {
     host.require_trust(window)?;
     let project = host.project(window)?;
-    let (root, cache, settings) = (project.root.clone(), project.build_cache_dir(), project.settings.effective());
-    let bridge_profiles = profiles.clone();
-    // What the Java language server and Build Project resolve the project with from now on.
-    let profiles_changed = tool == BuildTool::Maven
-        && ide_build::save_maven_profiles(&cache, &profiles).unwrap_or_else(|e| {
-            tracing::warn!("Maven profiles not saved: {e}");
-            false
-        });
-    if profiles_changed {
-        // The modules of the chosen profiles are read from the POMs with them from now on (the
-        // project tree's module folders too), whether or not Maven itself can run.
-        project.sink.emit(ide_core::IdeEvent::ProjectRootsChanged { root: project.root.clone().into() });
-    }
     let token = host.begin_project_request(window, request);
     let completion_token = token.clone();
-    let original_links = settings.languages.java.gradle.linked_projects.clone();
+    let bridge_profiles = profiles.clone();
+    let p = project.clone();
+    let config = host.config_dir.clone();
     let result = tokio::task::spawn_blocking(move || {
-        let current = load(&root, &cache, &settings);
-        let env = match tool {
-            BuildTool::Maven => current
+        let scopes = workspace::scopes(&p, &config)?;
+        let selected: Vec<_> =
+            scopes.iter().filter(|scope| workspace::selected(scope, &p.root, tool, build_dir.as_deref())).collect();
+        if selected.is_empty() {
+            return Err(IdeError::not_found("Build project is no longer linked"));
+        }
+        let mut profiles_changed = false;
+        for scope in selected {
+            if token.is_cancelled() {
+                return Err(IdeError::cancelled());
+            }
+            let (root, cache, settings) = (&scope.root, &scope.cache, &scope.settings);
+            let current = load(root, cache, settings);
+            if tool == BuildTool::Maven && current.maven.is_some() {
+                let changed = ide_build::save_maven_profiles(cache, &profiles).unwrap_or_else(|e| {
+                    tracing::warn!("Maven profiles not saved: {e}");
+                    false
+                });
+                if changed {
+                    p.sink.emit(IdeEvent::ProjectRootsChanged { root: p.root.clone().into() });
+                }
+                profiles_changed |= changed;
+            }
+            let env = current
                 .maven
                 .as_ref()
                 .and_then(|m| m.projects.iter().find(|p| !p.env.is_empty()))
                 .map(|p| p.env.clone())
-                .unwrap_or_default(),
-            BuildTool::Gradle => BTreeMap::new(),
-        };
-        let options = SyncOptions {
-            offline,
-            profiles,
-            env,
-            maven_command: ide_sdk::apply::maven_command(&root, &settings).map(|p| p.to_string_lossy().into_owned()),
-            maven_options: ide_sdk::apply::maven_options(&root, &settings),
-            maven_settings: settings.languages.java.maven.clone(),
-            gradle_command: None,
-        };
-        let progress = |p: SyncProgress| {
-            let _ = on_progress.send(p);
-        };
-        match tool {
-            BuildTool::Maven => ide_build::sync_maven(&root, &cache, &options, &token, &progress)?,
-            BuildTool::Gradle => {
-                if let Some(dir) = &build_dir
-                    && !current.gradle.iter().any(|g| &g.dir == dir)
-                {
-                    return Err(IdeError::not_found("Gradle project is no longer linked"));
+                .unwrap_or_default();
+            let options = SyncOptions {
+                offline,
+                profiles: profiles.clone(),
+                env,
+                maven_command: ide_sdk::apply::maven_command(root, settings).map(|p| p.to_string_lossy().into_owned()),
+                maven_options: ide_sdk::apply::maven_options(root, settings),
+                maven_settings: settings.languages.java.maven.clone(),
+                gradle_command: None,
+            };
+            let progress = |p: SyncProgress| {
+                let _ = on_progress.send(p);
+            };
+            match tool {
+                BuildTool::Maven if current.maven.is_some() => {
+                    ide_build::sync_maven(root, cache, &options, &token, &progress)?
                 }
-                for g in current.gradle.iter().filter(|g| build_dir.as_ref().is_none_or(|dir| dir == &g.dir)) {
-                    if token.is_cancelled() {
-                        return Err(IdeError::cancelled());
+                BuildTool::Maven => {}
+                BuildTool::Gradle => {
+                    for g in current
+                        .gradle
+                        .iter()
+                        .filter(|g| build_dir.as_ref().is_none_or(|dir| p.root.join(dir) == root.join(&g.dir)))
+                    {
+                        if token.is_cancelled() {
+                            return Err(IdeError::cancelled());
+                        }
+                        let options = SyncOptions {
+                            env: g.env.clone(),
+                            gradle_command: Some(g.command.clone()),
+                            ..options.clone()
+                        };
+                        ide_build::sync_gradle_model(root, cache, g, &options, &token, &progress)?;
                     }
-                    let options =
-                        SyncOptions { env: g.env.clone(), gradle_command: Some(g.command.clone()), ..options.clone() };
-                    ide_build::sync_gradle_model(&root, &cache, g, &options, &token, &progress)?;
-                }
-                if token.is_cancelled() {
-                    return Err(IdeError::cancelled());
                 }
             }
         }
-        Ok::<BuildModel, IdeError>(load(&root, &cache, &settings))
+        let scopes = workspace::scopes(&p, &config)?;
+        let model = workspace::load_scopes(&p.root, &scopes);
+        let updates = workspace::update_files(&p.root, &scopes, &model, tool);
+        Ok::<_, IdeError>((model, profiles_changed, updates))
     })
     .await
     .map_err(join_err);
     host.end_request(request);
-    let model = result??;
+    let (model, profiles_changed, updates) = result??;
     if completion_token.is_cancelled() {
         return Err(IdeError::cancelled());
     }
-    if tool == BuildTool::Gradle && original_links != project.settings.effective().languages.java.gradle.linked_projects
-    {
-        // A late sync must not re-import a build that was unlinked while it ran.
-        return tokio::task::spawn_blocking(move || {
-            load(&project.root, &project.build_cache_dir(), &project.settings.effective())
-        })
-        .await
-        .map_err(join_err);
-    }
     if tool == BuildTool::Gradle {
         // The sync may report project folders outside the project (`includeFlat`): index and list them.
         project.refresh_index_scope();
@@ -320,30 +326,17 @@ pub async fn build_sync(
     // to update the project configurations re-resolves them (#436). The same
     // holds for Gradle: it reuses its cached classpath on restart, so a
     // dependency added to `build.gradle` stays unresolved until told to sync.
-    let build_files: Vec<String> = match tool {
-        BuildTool::Maven => model.maven.iter().flat_map(|m| m.projects.iter().map(|p| p.pom.clone())).collect(),
-        BuildTool::Gradle => {
-            model.gradle.iter().flat_map(|g| g.projects.iter().filter_map(|p| p.build_file.clone())).collect()
-        }
-    };
     let lsp = project.lsp.clone();
-    // With a module of a reactor unlinked, jdtls imports the other modules one by one and
-    // not the reactor: naming the reactor here would import it again, all modules included.
-    let imported = match tool {
-        BuildTool::Maven => crate::project::jdtls_maven_import(&project.root, &project.settings.effective()).1,
-        BuildTool::Gradle => None,
-    };
-    let uris = match imported {
-        Some(files) => files.into_iter().filter(|f| f.ends_with("/pom.xml")).collect(),
-        None => build_files.iter().map(|f| ide_lsp::path_to_uri_string(&project.root.join(f))).collect(),
-    };
     tokio::spawn(async move {
         if profiles_changed {
             // jdtls takes the profiles from its Maven settings (see `ide_sdk::maven_profiles`).
             lsp.reconfigure().await;
         }
-        if let Err(e) = lsp.java_update_project_configs(&project.root, uris).await {
-            tracing::debug!("java/projectConfigurationsUpdate: {e}");
+        for file in updates {
+            let uri = ide_lsp::path_to_uri_string(&file);
+            if let Err(e) = lsp.java_update_project_configs(&file, vec![uri]).await {
+                tracing::debug!("java/projectConfigurationsUpdate: {e}");
+            }
         }
     });
     Ok(model)
@@ -353,12 +346,25 @@ pub async fn build_sync(
 /// module's own, else its nearest parent in the project; its path, text and declaration.
 fn declaring_pom(
     project: &Project,
+    config: &Path,
     pom: &str,
     dependency: &ArtifactKey,
 ) -> IdeResult<(std::path::PathBuf, String, Range)> {
-    let model = ide_build::maven::load(&project.root);
-    for rel in ide_build::pom_edit::declaring_poms(&model, pom) {
-        let path = project.root.join(&rel);
+    let scopes = workspace::scopes(project, config)?;
+    let path = project.root.join(pom);
+    let scope = scopes
+        .iter()
+        .filter(|s| path.starts_with(&s.root))
+        .max_by_key(|s| s.root.components().count())
+        .ok_or_else(|| IdeError::not_found("Maven project is no longer linked"))?;
+    let model = load(&scope.root, &scope.cache, &scope.settings).maven.unwrap_or_default();
+    let pom = model
+        .projects
+        .iter()
+        .find(|p| scope.root.join(&p.pom) == path)
+        .ok_or_else(|| IdeError::not_found("Maven project is no longer linked"))?;
+    for rel in ide_build::pom_edit::declaring_poms(&model, &pom.pom) {
+        let path = scope.root.join(&rel);
         let text = project.text_of(&path)?;
         if let Some(range) = ide_build::pom_edit::declaration(&text, dependency) {
             return Ok((path, text, range));
@@ -398,14 +404,19 @@ pub async fn gradle_dependencies(
 ) -> IdeResult<Vec<ide_build::GradleDependency>> {
     host.require_trust(window)?;
     let project = host.project(window)?;
-    let (root, cache, settings) = (project.root.clone(), project.build_cache_dir(), project.settings.effective());
+    let config = host.config_dir.clone();
     let token = host.begin_project_request(window, request);
     let result = tokio::task::spawn_blocking(move || {
-        let model = load(&root, &cache, &settings);
+        let scopes = workspace::scopes(&project, &config)?;
+        let scope = scopes
+            .iter()
+            .find(|s| workspace::selected(s, &project.root, BuildTool::Gradle, build_dir.as_deref()))
+            .ok_or_else(|| IdeError::not_found("Gradle project is no longer linked"))?;
+        let model = load(&scope.root, &scope.cache, &scope.settings);
         let gradle = model
             .gradle
             .iter()
-            .find(|g| build_dir.as_ref().is_none_or(|dir| &g.dir == dir))
+            .find(|g| build_dir.as_ref().is_none_or(|dir| project.root.join(dir) == scope.root.join(&g.dir)))
             .ok_or_else(|| IdeError::not_found("Gradle project is no longer linked"))?;
         let options = SyncOptions {
             offline,
@@ -413,7 +424,7 @@ pub async fn gradle_dependencies(
             gradle_command: Some(gradle.command.clone()),
             ..Default::default()
         };
-        ide_build::gradle_dependencies(&root, gradle, &options, &gradle_path, &configuration, &token)
+        ide_build::gradle_dependencies(&scope.root, gradle, &options, &gradle_path, &configuration, &token)
     })
     .await
     .map_err(join_err);
@@ -429,8 +440,9 @@ pub async fn maven_dependency_declaration(
     dependency: ArtifactKey,
 ) -> IdeResult<Location> {
     let project = host.project(window)?;
+    let config = host.config_dir.clone();
     tokio::task::spawn_blocking(move || {
-        let (path, _, range) = declaring_pom(&project, &pom, &dependency)?;
+        let (path, _, range) = declaring_pom(&project, &config, &pom, &dependency)?;
         Ok(Location::file(path, range))
     })
     .await
@@ -469,8 +481,9 @@ pub async fn maven_exclude_dependency(
     exclusion: ArtifactKey,
 ) -> IdeResult<Location> {
     let project = host.project(window)?;
+    let config = host.config_dir.clone();
     tokio::task::spawn_blocking(move || {
-        let (path, text, range) = declaring_pom(&project, &pom, &dependency)?;
+        let (path, text, range) = declaring_pom(&project, &config, &pom, &dependency)?;
         match ide_build::pom_edit::add_exclusion(&text, &dependency, &exclusion) {
             Some(Exclusion::Edit(edit)) => {
                 let edit = WorkspaceEdit {
diff --git a/crates/ide-host/src/ops/build/workspace.rs b/crates/ide-host/src/ops/build/workspace.rs
new file mode 100644
index 000000000..c05337b1b
--- /dev/null
+++ b/crates/ide-host/src/ops/build/workspace.rs
@@ -0,0 +1,231 @@
+use super::*;
+use std::path::PathBuf;
+
+pub(super) struct Scope {
+    pub root: PathBuf,
+    pub cache: PathBuf,
+    pub settings: Settings,
+}
+
+pub(super) fn scopes(project: &Project, config: &Path) -> IdeResult<Vec<Scope>> {
+    scopes_at(&project.root, &project.build_cache_dir(), config, project.settings.effective())
+}
+
+fn scopes_at(root: &Path, cache: &Path, config: &Path, settings: Settings) -> IdeResult<Vec<Scope>> {
+    Ok(match ide_workspace::workspace::Workspace::load(root)? {
+        Some(workspace) => workspace
+            .projects
+            .into_iter()
+            .filter(|p| p.is_dir())
+            .map(|root| Scope {
+                cache: cache.join(crate::project::project_key(&root)),
+                settings: ide_workspace::SettingsStore::load(config, Some(&root)).effective(),
+                root,
+            })
+            .collect(),
+        None => vec![Scope { root: root.to_owned(), cache: cache.to_owned(), settings }],
+    })
+}
+
+fn absolute(root: &Path, path: &str) -> String {
+    let path = if path.is_empty() { root.to_owned() } else { root.join(path) };
+    ide_core::ipc_path::to_ipc(&path)
+}
+
+pub(super) fn load_scopes(root: &Path, scopes: &[Scope]) -> BuildModel {
+    let mut combined = BuildModel::default();
+    for scope in scopes {
+        let mut model = load(&scope.root, &scope.cache, &scope.settings);
+        if scope.root == root {
+            return model;
+        }
+        if let Some(maven) = &mut model.maven {
+            let owner = ide_core::ipc_path::to_ipc(&scope.root);
+            for p in &mut maven.projects {
+                p.project_root = Some(owner.clone());
+                p.pom = absolute(&scope.root, &p.pom);
+                p.dir = absolute(&scope.root, &p.dir);
+                for module in &mut p.modules {
+                    *module = absolute(&scope.root, module);
+                }
+            }
+            for profile in &mut maven.profiles {
+                profile.project_root = Some(owner.clone());
+            }
+        }
+        if let Some(maven) = model.maven {
+            match &mut combined.maven {
+                None => combined.maven = Some(maven),
+                Some(all) => {
+                    all.projects.extend(maven.projects);
+                    all.profiles.extend(maven.profiles);
+                    all.synced_at = match (all.synced_at, maven.synced_at) {
+                        (Some(a), Some(b)) => Some(a.min(b)),
+                        _ => None,
+                    };
+                    all.stale |= maven.stale;
+                    if let Some(error) = maven.sync_error {
+                        all.sync_error = Some(match all.sync_error.take() {
+                            Some(previous) => format!("{previous}\n{error}"),
+                            None => error,
+                        });
+                    }
+                }
+            }
+        }
+        for g in &mut model.gradle {
+            g.dir = absolute(&scope.root, &g.dir);
+            for p in &mut g.projects {
+                p.dir = absolute(&scope.root, &p.dir);
+                p.build_file = p.build_file.as_ref().map(|f| absolute(&scope.root, f));
+            }
+        }
+        combined.gradle.extend(model.gradle);
+    }
+    combined
+}
+
+pub(super) fn load_project(project: &Project, config: &Path) -> IdeResult<BuildModel> {
+    Ok(load_scopes(&project.root, &scopes(project, config)?))
+}
+
+pub(super) fn selected(scope: &Scope, window_root: &Path, tool: BuildTool, dir: Option<&str>) -> bool {
+    let Some(dir) = dir else { return true };
+    match tool {
+        BuildTool::Maven => scope.root == Path::new(dir),
+        BuildTool::Gradle => load(&scope.root, &scope.cache, &scope.settings)
+            .gradle
+            .iter()
+            .any(|g| window_root.join(dir) == scope.root.join(&g.dir)),
+    }
+}
+
+/// Build files select their member's language server, including independent nested builds.
+pub(super) fn update_files(root: &Path, scopes: &[Scope], model: &BuildModel, tool: BuildTool) -> Vec<PathBuf> {
+    let mut files = Vec::new();
+    match tool {
+        BuildTool::Maven => {
+            for scope in scopes {
+                // A reactor with unlinked modules must not be imported as a whole again.
+                let imported = crate::project::jdtls_maven_import(&scope.root, &scope.settings).1;
+                let paths: Vec<_> = match imported {
+                    Some(uris) => uris
+                        .iter()
+                        .filter_map(|u| ide_lsp::uri_to_path(u))
+                        .filter(|p| p.file_name().is_some_and(|n| n == "pom.xml"))
+                        .collect(),
+                    None => model
+                        .maven
+                        .iter()
+                        .flat_map(|m| &m.projects)
+                        .filter(|p| p.project_root.as_ref().is_none_or(|owner| Path::new(owner) == scope.root))
+                        .map(|p| root.join(&p.pom))
+                        .collect(),
+                };
+                for path in paths {
+                    if !files.contains(&path) {
+                        files.push(path);
+                    }
+                }
+            }
+        }
+        BuildTool::Gradle => {
+            for file in model.gradle.iter().flat_map(|g| &g.projects).filter_map(|p| p.build_file.as_ref()) {
+                let path = root.join(file);
+                if !files.contains(&path) {
+                    files.push(path);
+                }
+            }
+        }
+    }
+    files
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn workspace_models_use_member_settings_paths_and_caches() {
+        let temp = tempfile::tempdir().unwrap();
+        let base = dunce::canonicalize(temp.path()).unwrap();
+        let workspace = base.join("workspace");
+        let config = base.join("config");
+        let cache = base.join("cache");
+        let members: Vec<_> = ["first", "second"].into_iter().map(|name| base.join(name)).collect();
+        for member in &members {
+            std::fs::create_dir_all(member.join("extra")).unwrap();
+            std::fs::write(
+                member.join("pom.xml"),
+                r#"<project><artifactId>app</artifactId>
+              <profiles><profile><id>extra</id><modules><module>extra</module></modules></profile></profiles>
+            </project>"#,
+            )
+            .unwrap();
+            std::fs::write(member.join("extra/pom.xml"), "<project><artifactId>extra</artifactId></project>").unwrap();
+            std::fs::write(member.join("settings.gradle"), "rootProject.name = 'app'").unwrap();
+            std::fs::write(member.join("build.gradle"), "").unwrap();
+        }
+        ide_workspace::workspace::Workspace::save(&workspace, "Workspace", members.clone(), true).unwrap();
+        let first_cache = cache.join(crate::project::project_key(&members[0]));
+        ide_build::save_maven_profiles(&first_cache, &["extra".into()]).unwrap();
+        let settings = ide_workspace::SettingsStore::load(&config, Some(&members[1]));
+        settings
+            .set(
+                ide_workspace::settings::SettingsScope::Project,
+                "languages.java.gradle.linkedProjects",
+                serde_json::json!([]),
+            )
+            .unwrap();
+        let scopes = scopes_at(&workspace, &cache, &config, Settings::default()).unwrap();
+        assert_eq!(scopes[0].cache, first_cache);
+        let model = load_scopes(&workspace, &scopes);
+        let maven = model.maven.as_ref().unwrap();
+        assert_eq!(maven.projects.len(), 3);
+        assert_eq!(maven.projects[0].modules, [absolute(&members[0], "extra/pom.xml")]);
+        assert!(maven.projects.iter().all(|p| Path::new(&p.pom).is_absolute() && Path::new(&p.dir).is_absolute()));
+        assert_eq!(maven.profiles.len(), 2);
+        assert_ne!(maven.profiles[0].project_root, maven.profiles[1].project_root);
+        let updates = update_files(&workspace, &scopes, &model, BuildTool::Maven);
+        assert_eq!(updates.len(), 3);
+        assert!(updates.iter().all(|p| members.iter().any(|root| p.starts_with(root))));
+        assert_eq!(update_files(&workspace, &scopes, &model, BuildTool::Gradle), [members[0].join("build.gradle")]);
+        assert_eq!(model.gradle.len(), 1);
+        assert_eq!(model.gradle[0].dir, absolute(&members[0], ""));
+        assert!(selected(&scopes[0], &workspace, BuildTool::Maven, Some(&absolute(&members[0], ""))));
+        assert!(!selected(&scopes[1], &workspace, BuildTool::Maven, Some(&absolute(&members[0], ""))));
+        assert!(selected(&scopes[0], &workspace, BuildTool::Gradle, Some(&model.gradle[0].dir)));
+        assert!(!selected(&scopes[1], &workspace, BuildTool::Gradle, Some(&model.gradle[0].dir)));
+        assert_eq!(ide_build::maven_profiles(&scopes[1].cache), Vec::<String>::new());
+        let standalone = scopes_at(&members[0], &cache, &config, Settings::default()).unwrap();
+        assert_eq!(load_scopes(&members[0], &standalone), load(&members[0], &cache, &Settings::default()));
+        ide_workspace::workspace::Workspace::save(&workspace, "Workspace", vec![members[1].clone()], false).unwrap();
+        let scopes = scopes_at(&workspace, &cache, &config, Settings::default()).unwrap();
+        let model = load_scopes(&workspace, &scopes);
+        assert_eq!(model.maven.unwrap().projects.len(), 1);
+        assert!(model.gradle.is_empty());
+        std::fs::remove_dir_all(&members[1]).unwrap();
+        let scopes = scopes_at(&workspace, &cache, &config, Settings::default()).unwrap();
+        assert_eq!(load_scopes(&workspace, &scopes), BuildModel::default());
+    }
+
+    #[test]
+    fn reload_keeps_unlinked_modules_out_of_member_language_servers() {
+        let temp = tempfile::tempdir().unwrap();
+        let root = dunce::canonicalize(temp.path()).unwrap();
+        for name in ["enabled", "hidden"] {
+            std::fs::create_dir(root.join(name)).unwrap();
+            std::fs::write(
+                root.join(name).join("pom.xml"),
+                format!("<project><artifactId>{name}</artifactId></project>"),
+            )
+            .unwrap();
+        }
+        std::fs::write(root.join("pom.xml"), "<project><artifactId>parent</artifactId><packaging>pom</packaging><modules><module>enabled</module><module>hidden</module></modules></project>").unwrap();
+        let mut settings = Settings::default();
+        settings.languages.java.maven.unlinked_projects = vec!["hidden/pom.xml".into()];
+        let scope = Scope { root: root.clone(), cache: root.join("cache"), settings };
+        let model = load(&scope.root, &scope.cache, &scope.settings);
+        assert_eq!(update_files(&root, &[scope], &model, BuildTool::Maven), [root.join("enabled/pom.xml")]);
+    }
+}
diff --git a/crates/ide-host/tests/workspaces.rs b/crates/ide-host/tests/workspaces.rs
index 1b86eeca3..077615cfe 100644
--- a/crates/ide-host/tests/workspaces.rs
+++ b/crates/ide-host/tests/workspaces.rs
@@ -165,3 +165,44 @@ async fn php_language_level_follows_the_member_of_the_file() {
     assert_eq!(level_elsewhere.member, None);
     host.close_project("main");
 }
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn build_tool_availability_follows_workspace_members_and_trust() {
+    let temp = tempfile::tempdir().unwrap();
+    let base = dunce::canonicalize(temp.path()).unwrap();
+    let members: Vec<_> = ["first", "second"].into_iter().map(|name| base.join(name)).collect();
+    for member in &members {
+        std::fs::create_dir(member).unwrap();
+        std::fs::write(member.join("pom.xml"), "<project><artifactId>app</artifactId></project>").unwrap();
+        std::fs::write(member.join("build.gradle"), "").unwrap();
+    }
+    let root = base.join("workspace");
+    Workspace::save(&root, "Build tools", members.clone(), true).unwrap();
+    let host = Host::new(HostConfig {
+        config_dir: base.join("config"),
+        data_dir: base.join("data"),
+        local_data_dir: base.join("data"),
+        languages: Arc::new(ide_language::LanguageRegistry::load(None).unwrap()),
+        syntax: Arc::default(),
+        sink_for: Box::new(|_| Arc::new(NullSink)),
+        owner: |w| w,
+        runtime: tokio::runtime::Handle::current(),
+        project_environment: false,
+    });
+    for member in &members {
+        host.trust.decide(member, true, false).unwrap();
+    }
+    host.open_project("main", &root).unwrap();
+    assert!(ops::build::build_model(&host, "main").await.is_err());
+    host.close_project("main");
+    host.trust.decide(&root, true, false).unwrap();
+    host.open_project("main", &root).unwrap();
+    let model = ops::build::build_model(&host, "main").await.unwrap();
+    assert_eq!(model.maven.unwrap().projects.len(), 2);
+    assert_eq!(model.gradle.len(), 2);
+    ops::project::save_workspace(&host, "main", "One member", vec![members[1].clone()]).unwrap();
+    let model = ops::build::build_model(&host, "main").await.unwrap();
+    assert_eq!(model.maven.unwrap().projects[0].dir, ide_core::ipc_path::to_ipc(&members[1]));
+    assert_eq!(model.gradle.len(), 1);
+    host.close_project("main");
+}
diff --git a/src/bindings.ts b/src/bindings.ts
index 7ab772183..1da620525 100644
--- a/src/bindings.ts
+++ b/src/bindings.ts
@@ -5581,11 +5581,15 @@ export type MavenPlugin = {
 };
 
 export type MavenProfile = {
+	/**  Owning project folder when displayed in a workspace. */
+	projectRoot?: string | null,
 	id: string,
 	activeByDefault: boolean,
 };
 
 export type MavenProject = {
+	/**  Owning project folder when displayed in a workspace. */
+	projectRoot?: string | null,
 	/**  Project-relative, `/`-separated (`pom.xml`, `core/pom.xml`). */
 	pom: string,
 	/**  Project-relative directory; `""` = the project root. */
diff --git a/src/features/build-tools/BuildToolView.tsx b/src/features/build-tools/BuildToolView.tsx
index 5bec54b98..0fe43f20b 100644
--- a/src/features/build-tools/BuildToolView.tsx
+++ b/src/features/build-tools/BuildToolView.tsx
@@ -238,7 +238,7 @@ function NodeRow({ node, state }: { node: BuildNode; state: TreeRowState }) {
       <span className={styles.row} onClick={(e) => e.stopPropagation()} onDoubleClick={(e) => e.stopPropagation()}>
         <Checkbox
           checked={profileChecked(node.profile, choices)}
-          onChange={(v) => setProfile(node.profile.id, v)}
+          onChange={(v) => setProfile(node.profile, v)}
           label={node.profile.id}
           className={styles.profile}
         />
@@ -246,13 +246,15 @@ function NodeRow({ node, state }: { node: BuildNode; state: TreeRowState }) {
     );
   }
   const detail =
-    node.kind === "dependency" && node.dependency.scope !== "compile"
-      ? `(${node.dependency.scope}${node.dependency.optional ? ", optional" : ""})`
-      : node.kind === "dependency" && node.dependency.optional
-        ? "(optional)"
-        : node.kind === "task"
-          ? node.task.description
-          : null;
+    node.kind === "profiles" && node.projectRoot
+      ? node.projectRoot.split("/").pop()
+      : node.kind === "dependency" && node.dependency.scope !== "compile"
+        ? `(${node.dependency.scope}${node.dependency.optional ? ", optional" : ""})`
+        : node.kind === "dependency" && node.dependency.optional
+          ? "(optional)"
+          : node.kind === "task"
+            ? node.task.description
+            : null;
   return (
     <span className={styles.row} title={node.kind === "task" ? (node.task.description ?? undefined) : undefined}>
       <Icon name={nodeIcon(node)} size={16} className={styles.icon} />
@@ -338,7 +340,8 @@ function BuildToolView({ tool }: { tool: BuildTool }) {
         {
           label: "Open pom.xml",
           icon: "file-maven",
-          run: () => void editorService().openFile(`${root}/${node.project.pom}`),
+          run: () =>
+            void editorService().openFile(node.project.projectRoot ? node.project.pom : `${root}/${node.project.pom}`),
         },
         { kind: "action", action: "maven.reload", label: "Reload All Maven Projects" },
         { kind: "action", action: "maven.executeGoal" },
@@ -415,7 +418,7 @@ function BuildToolView({ tool }: { tool: BuildTool }) {
           renderNode={(n, state) => <NodeRow node={n} state={state} />}
           onActivate={(n) => {
             if (n.kind === "profile") {
-              setProfile(n.profile.id, !profileChecked(n.profile, useBuild.getState().settings.maven.profiles));
+              setProfile(n.profile, !profileChecked(n.profile, useBuild.getState().settings.maven.profiles));
               return;
             }
             if (isRunnable(n)) run([n], "run");
diff --git a/src/features/build-tools/index.ts b/src/features/build-tools/index.ts
index cfca30600..5703f6af7 100644
--- a/src/features/build-tools/index.ts
+++ b/src/features/build-tools/index.ts
@@ -22,7 +22,15 @@ import { ExecutePopupHost } from "./ExecutePopup";
 import { pomNavigationExtension } from "./pomNavigation";
 import { buildToolsRunAnything } from "./runAnything";
 import { versionCatalogExtension } from "./versionCatalog";
-import { expandableKeys, gradleChildren, gradleRoots, mavenChildren, mavenRoots, gradleProjectKey } from "./model";
+import {
+  expandableKeys,
+  gradleChildren,
+  gradleRoots,
+  mavenChildren,
+  mavenRoots,
+  mavenPomAtPath,
+  gradleProjectKey,
+} from "./model";
 import {
   ANALYZER_KIND,
   addProjects,
@@ -81,8 +89,8 @@ function analyzerPom(arg: unknown): string | null {
   const a = (arg ?? {}) as { pom?: unknown; path?: unknown };
   if (typeof a.pom === "string") return a.pom;
   if (typeof a.path === "string" && root) {
-    const rel = a.path.startsWith(`${root}/`) ? a.path.slice(root.length + 1) : a.path;
-    if (projects.some((p) => p.pom === rel)) return rel;
+    const pom = mavenPomAtPath(projects, root, a.path);
+    if (pom) return pom;
   }
   return current.maven ?? null;
 }
@@ -143,10 +151,12 @@ function apply(model: BuildModel | null, registered: Partial<Record<BuildTool, (
   }
   // Import each independent build once; linking another build must not be hidden by the first sync.
   const root = useBuild.getState().root;
-  const mavenKey = `maven:${root}`;
-  if (model?.maven?.projects.length && model.maven.syncedAt == null && !synced.has(mavenKey)) {
-    synced.add(mavenKey);
-    requestSync("maven");
+  for (const member of new Set(model?.maven?.projects.map((p) => p.projectRoot ?? null))) {
+    const key = JSON.stringify(["maven", root, member]);
+    if (model?.maven?.syncedAt == null && !synced.has(key)) {
+      synced.add(key);
+      requestSync("maven", member);
+    }
   }
   for (const build of model?.gradle ?? []) {
     const key = JSON.stringify([root, build.dir]);
@@ -209,8 +219,8 @@ export function activate(): () => void {
         const path = paths.length === 1 && !dirs?.[0] ? paths[0]! : null;
         if (!path || !path.endsWith("/pom.xml")) return [];
         const { model, root } = useBuild.getState();
-        const pom = root && path.startsWith(`${root}/`) ? path.slice(root.length + 1) : null;
-        if (!pom || !model?.maven?.projects.some((p) => p.pom === pom)) return [];
+        const pom = mavenPomAtPath(model?.maven?.projects ?? [], root, path);
+        if (!pom) return [];
         return [{ kind: "action", action: "maven.analyzeDependencies", arg: { pom }, label: "Analyze Dependencies…" }];
       },
     }),
@@ -269,7 +279,7 @@ export function activate(): () => void {
         title: "Add Maven Projects",
         category: "Maven",
         icon: "plus",
-        when: "projectOpen",
+        when: "projectOpen && !workspaceOpen",
         run: () => addProjects(),
       },
       {
@@ -277,7 +287,7 @@ export function activate(): () => void {
         title: "Unlink Maven Projects",
         category: "Maven",
         hidden: true,
-        when: MAVEN_WHEN,
+        when: `${MAVEN_WHEN} && !workspaceOpen`,
         run: ({ arg }) => unlinkProjects(analyzerPom(arg)),
       },
       {
diff --git a/src/features/build-tools/model.test.ts b/src/features/build-tools/model.test.ts
index 7b9f39b76..332ff454a 100644
--- a/src/features/build-tools/model.test.ts
+++ b/src/features/build-tools/model.test.ts
@@ -12,6 +12,7 @@ import {
   mavenChildren,
   mavenGoalConfig,
   mavenRoots,
+  mavenPomAtPath,
   nodeIcon,
   nodeLabel,
   parseGoalLine,
@@ -395,3 +396,14 @@ describe("Gradle tree and runs", () => {
     expect(taskCompletions("clean wr", gradle).map((c) => c.line)).toEqual(["clean wrapper"]);
   });
 });
+
+it.each([
+  ["pom.xml", "/workspace/pom.xml"],
+  ["module/pom.xml", "/workspace/module/pom.xml"],
+  ["/linked/pom.xml", "/linked/pom.xml"],
+  ["/workspace/member/pom.xml", "/workspace/member/pom.xml"],
+])("resolves the Maven model POM %s at %s", (pom, path) => {
+  const projects = [project({ pom })];
+  expect(mavenPomAtPath(projects, "/workspace", path)).toBe(pom);
+  expect(mavenPomAtPath(projects, "/workspace", "/other/pom.xml")).toBeNull();
+});
diff --git a/src/features/build-tools/model.ts b/src/features/build-tools/model.ts
index a72b32fd4..3118d975e 100644
--- a/src/features/build-tools/model.ts
+++ b/src/features/build-tools/model.ts
@@ -55,7 +55,7 @@ export const ALL_PHASES = [
 ];
 
 export type BuildNode =
-  | { kind: "profiles"; key: string }
+  | { kind: "profiles"; key: string; projectRoot?: string | null }
   | { kind: "profile"; key: string; profile: MavenProfile }
   | { kind: "mavenProject"; key: string; project: MavenProject }
   | { kind: "lifecycle"; key: string; project: MavenProject }
@@ -76,7 +76,7 @@ export type BuildNode =
 export interface MavenRunOptions {
   offline: boolean;
   skipTests: boolean;
-  /** Explicit profile choices: id → checked. Unlisted profiles keep their default. */
+  /** Explicit profile choices by profileKey. Unlisted profiles keep their default. */
   profiles: Record<string, boolean>;
 }
 
@@ -100,9 +100,14 @@ export function pluginLabel(p: MavenPlugin): string {
   return `${p.prefix} (${p.groupId}:${p.artifactId}${p.version ? `:${p.version}` : ""})`;
 }
 
+/** Profile choices in different workspace members are independent. */
+export function profileKey(profile: MavenProfile): string {
+  return profile.projectRoot ? JSON.stringify([profile.projectRoot, profile.id]) : profile.id;
+}
+
 /** Whether a profile is active for runs: the explicit choice, else `activeByDefault`. */
 export function profileChecked(profile: MavenProfile, choices: Record<string, boolean>): boolean {
-  return choices[profile.id] ?? profile.activeByDefault;
+  return choices[profileKey(profile)] ?? profile.activeByDefault;
 }
 
 /** `-P` value for the choices that differ from the defaults (`a,!b`), or null. */
@@ -123,11 +128,17 @@ export function profilesList(profiles: readonly MavenProfile[], choices: Record<
 
 export function mavenRoots(model: MavenModel): BuildNode[] {
   const out: BuildNode[] = [];
-  if (model.profiles.length) out.push({ kind: "profiles", key: "mvn:profiles" });
+  for (const projectRoot of new Set(model.profiles.map((p) => p.projectRoot)))
+    out.push({ kind: "profiles", key: `mvn:profiles${projectRoot ?? ""}`, projectRoot });
   for (const p of model.projects) if (!p.aggregated) out.push({ kind: "mavenProject", key: projectKey(p), project: p });
   return out;
 }
 
+/** Resolves a POM from either a project-relative or workspace-absolute model path. */
+export function mavenPomAtPath(projects: readonly MavenProject[], root: string | null, path: string): string | null {
+  return projects.find((p) => p.pom === path || (root && `${root}/${p.pom}` === path))?.pom ?? null;
+}
+
 /** Run configurations of a Maven project: `maven` configs whose directory is the project's. */
 export function mavenRunConfigs(project: MavenProject, configs: readonly RunConfig[]): RunConfig[] {
   return configs.filter((c) => c.kind === "maven" && normalizeDir(c.cwd) === project.dir);
@@ -171,7 +182,9 @@ export function mavenChildren(
 ): BuildNode[] | undefined {
   switch (node.kind) {
     case "profiles":
-      return model.profiles.map((profile) => ({ kind: "profile", key: `mvn:profile:${profile.id}`, profile }));
+      return model.profiles
+        .filter((p) => p.projectRoot === node.projectRoot)
+        .map((profile) => ({ kind: "profile", key: `mvn:profile:${profileKey(profile)}`, profile }));
     case "mavenProject": {
       const p = node.project;
       const k = projectKey(p);
@@ -474,7 +487,11 @@ export function mavenGoalConfig(
   model: Pick<MavenModel, "profiles">,
   options: MavenRunOptions,
 ): RunConfig {
-  const args = mavenArgs(goals, model, options);
+  const args = mavenArgs(
+    goals,
+    { profiles: model.profiles.filter((p) => p.projectRoot === project.projectRoot) },
+    options,
+  );
   return {
     id: `maven:goal:${project.pom}:${goals.join(" ")}`,
     name: mavenConfigName(project, goals),
diff --git a/src/features/build-tools/store.ts b/src/features/build-tools/store.ts
index c4976709b..0e1945add 100644
--- a/src/features/build-tools/store.ts
+++ b/src/features/build-tools/store.ts
@@ -18,6 +18,7 @@ import {
   nextRequestId,
   type BuildModel,
   type BuildTool,
+  type MavenProfile,
   type RequestId,
   type RunConfig,
   type SyncProgress,
@@ -27,7 +28,7 @@ import { useBuildModel } from "@/platform/buildModel";
 import { useProject } from "@/platform/project";
 import { editorService, notifications } from "@/workbench/contributions";
 import { cancelTask, removeTask, upsertTask, useTasks } from "@/workbench/tasks";
-import { gradleRoots, profilesList, type GradleRunOptions, type MavenRunOptions } from "./model";
+import { gradleRoots, profileKey, profilesList, type GradleRunOptions, type MavenRunOptions } from "./model";
 
 export interface BuildSettings {
   maven: MavenRunOptions;
@@ -126,15 +127,20 @@ export const toggleGradleOffline = () =>
 /** Delay before reloading Maven after a profile toggle, so a few toggles in a row reload once. */
 export const PROFILE_RELOAD_DELAY_MS = 800;
 let profileReload: ReturnType<typeof setTimeout> | undefined;
+const profileRoots = new Set<string | null>();
 
-export function setProfile(id: string, checked: boolean) {
+export function setProfile(profile: string | MavenProfile, checked: boolean) {
+  const id = typeof profile === "string" ? profile : profileKey(profile);
+  const projectRoot = typeof profile === "string" ? null : (profile.projectRoot ?? null);
   updateSettings((s) => ({ ...s, maven: { ...s.maven, profiles: { ...s.maven.profiles, [id]: checked } } }));
   // The Java language server and Build Project resolve the project with the profiles of the
   // last sync, so a new choice reloads it (IDEA re-imports on a profile change too).
+  profileRoots.add(projectRoot);
   clearTimeout(profileReload);
   profileReload = setTimeout(() => {
     profileReload = undefined;
-    requestSync("maven");
+    for (const root of profileRoots) requestSync("maven", root);
+    profileRoots.clear();
   }, PROFILE_RELOAD_DELAY_MS);
 }
 
@@ -240,7 +246,7 @@ const LINKED_PROJECTS = "languages.java.maven.linkedProjects";
  * reactor lists them), or removes them (a linked one is dropped, a discovered one unlinked).
  */
 async function setLinked(root: string, poms: string[], linked: boolean) {
-  if (useProject.getState().project?.root !== root) return;
+  if (useProject.getState().project?.root !== root || useProject.getState().project?.workspace) return;
   const settings = await commands.settingsGet();
   if (useProject.getState().project?.root !== root) return;
   const maven = settings.languages.java?.maven;
@@ -266,7 +272,7 @@ async function setLinked(root: string, poms: string[], linked: boolean) {
 export async function unlinkProjects(pom: string | null) {
   const { root, model } = useBuild.getState();
   const project = model?.maven?.projects.find((p) => p.pom === pom);
-  if (!root || !pom || !project) return;
+  if (!root || !pom || !project || useProject.getState().project?.workspace) return;
   if (
     !(await confirm({
       title: "Unlink Maven projects?",
@@ -295,7 +301,7 @@ function projectPoms(root: string, picked: readonly string[]): string[] {
 
 export async function addProjects() {
   const root = useProject.getState().project?.root;
-  if (!root || !isTauri()) return;
+  if (!root || useProject.getState().project?.workspace || !isTauri()) return;
   const { open } = await import("@tauri-apps/plugin-dialog");
   const picked = await open({
     title: tx`Add Maven Projects`,
@@ -392,7 +398,7 @@ export function requestSync(tool: BuildTool, buildDir: string | null = null) {
   } else void syncTool(tool, buildDir);
 }
 
-/** Reloads the build tool model; `buildDir` limits a Gradle reload to one linked build. */
+/** Reloads one Maven workspace member / linked Gradle build, or all builds when `buildDir` is null. */
 export async function syncTool(tool: BuildTool, buildDir: string | null = null): Promise<void> {
   const state = useBuild.getState();
   const gen = generation;
@@ -411,10 +417,27 @@ export async function syncTool(tool: BuildTool, buildDir: string | null = null):
     upsertTask({ id: taskId, title: TITLES[tool], message: p.message, fraction: p.fraction, done: false, cancel });
   };
   const { settings, model } = state;
-  const profiles = tool === "maven" && model?.maven ? profilesList(model.maven.profiles, settings.maven.profiles) : [];
   const offline = tool === "maven" ? settings.maven.offline : settings.gradle.offline;
   try {
-    const next = await call(commands.buildSync(tool, request, offline, profiles, buildDir, channel));
+    const roots =
+      tool === "maven" && useProject.getState().project?.workspace
+        ? [...new Set(model?.maven?.projects.map((p) => p.projectRoot ?? null))].filter(
+            (r) => !buildDir || r === buildDir,
+          )
+        : [buildDir];
+    let next = model;
+    for (const dir of roots) {
+      if (useBuild.getState().root !== root || useBuild.getState().syncing[tool]?.request !== request) return;
+      const profiles =
+        tool === "maven" && model?.maven
+          ? profilesList(
+              model.maven.profiles.filter((p) => (p.projectRoot ?? null) === dir),
+              settings.maven.profiles,
+            )
+          : [];
+      next = await call(commands.buildSync(tool, request, offline, profiles, dir, channel));
+    }
+    if (!next) return;
     if (useBuild.getState().root !== root || gen !== generation) return;
     const configs = await call(commands.runConfigs()).catch(() => useBuild.getState().configs);
     if (useBuild.getState().root !== root || gen !== generation) return;
@@ -472,6 +495,7 @@ export function resetBuild() {
   generation++;
   clearTimeout(profileReload);
   profileReload = undefined;
+  profileRoots.clear();
   queuedSyncs.clear();
   useAnalyzer.setState({ module: null });
   for (const tool of ["maven", "gradle"] as const) {
diff --git a/src/features/build-tools/workspace.test.tsx b/src/features/build-tools/workspace.test.tsx
new file mode 100644
index 000000000..5e6167ab1
--- /dev/null
+++ b/src/features/build-tools/workspace.test.tsx
@@ -0,0 +1,214 @@
+import { afterEach, beforeEach, expect, it, vi } from "vitest";
+import { act, fireEvent, render, screen } from "@testing-library/react";
+import type { BuildModel, ProjectInfo, RunConfig } from "@/platform/ipc";
+import { registerAction } from "@/platform/actions";
+import { setContext } from "@/platform/context";
+import { useProject } from "@/platform/project";
+import { MavenView, GradleView } from "./BuildToolView";
+import { activate } from "./index";
+import { expandableKeys, gradleChildren, gradleRoots, mavenChildren, mavenRoots, profileKey } from "./model";
+import { executeBuildLine } from "./runAnything";
+import { loadModel, PROFILE_RELOAD_DELAY_MS, resetBuild, setProfile, syncTool, useBuild } from "./store";
+
+const mocks = vi.hoisted(() => ({ model: vi.fn(), sync: vi.fn() }));
+vi.mock("@/platform/ipc", async (original) => {
+  const real = await original<typeof import("@/platform/ipc")>();
+  return {
+    ...real,
+    isTauri: () => true,
+    call: (value: unknown) => value,
+    commands: {
+      ...real.commands,
+      buildModel: mocks.model,
+      runConfigs: () => Promise.resolve([]),
+      buildSync: mocks.sync,
+      cancelRequest: () => Promise.resolve(),
+    },
+  };
+});
+vi.mock("@tauri-apps/api/core", async (original) => ({
+  ...(await original<typeof import("@tauri-apps/api/core")>()),
+  Channel: class {
+    onmessage: unknown = null;
+  },
+}));
+
+const members = ["/projects/first", "/projects/second"];
+const model: BuildModel = {
+  maven: {
+    syncedAt: 1,
+    stale: false,
+    syncError: null,
+    profiles: members.map((projectRoot) => ({ id: "local", activeByDefault: false, projectRoot })),
+    projects: members.map((projectRoot) => ({
+      projectRoot,
+      pom: `${projectRoot}/pom.xml`,
+      dir: projectRoot,
+      groupId: "example",
+      artifactId: "app",
+      version: "1",
+      packaging: "jar",
+      displayName: projectRoot.split("/").pop()!,
+      parent: null,
+      modules: [],
+      aggregated: false,
+      plugins: [],
+      dependencies: [],
+      profiles: ["local"],
+      javaVersion: null,
+      command: `${projectRoot}/mvnw`,
+      options: [],
+      env: {},
+    })),
+  },
+  gradle: members.map((dir) => ({
+    dir,
+    command: `${dir}/gradlew`,
+    env: {},
+    javaVersion: null,
+    syncedAt: 1,
+    stale: false,
+    syncError: null,
+    projects: [
+      {
+        path: ":",
+        name: dir.split("/").pop()!,
+        dir,
+        buildFile: `${dir}/build.gradle`,
+        tasks: [{ name: "test", group: "verification", description: null }],
+      },
+    ],
+  })),
+};
+let dispose: () => void;
+beforeEach(async () => {
+  vi.clearAllMocks();
+  localStorage.clear();
+  resetBuild();
+  useProject.setState({
+    project: {
+      root: "/workspace",
+      trusted: true,
+      workspace: { version: 1, name: "Workspace", projects: members },
+    } as ProjectInfo,
+  });
+  setContext("projectOpen", true);
+  setContext("workspaceOpen", true);
+  mocks.model.mockResolvedValue(model);
+  mocks.sync.mockResolvedValue(model);
+  await act(async () => {
+    dispose = activate();
+  });
+});
+afterEach(() => {
+  dispose();
+  resetBuild();
+  useProject.setState({ project: null });
+  setContext("projectOpen", false);
+  setContext("workspaceOpen", false);
+  vi.useRealTimers();
+});
+
+it("lists linked Maven projects and keeps duplicate profile choices and goal directories independent", async () => {
+  const maven = model.maven!;
+  const roots = mavenRoots(maven);
+  act(() =>
+    useBuild.setState((s) => ({
+      expanded: { ...s.expanded, maven: expandableKeys(roots, (n) => mavenChildren(n, maven, [])) },
+    })),
+  );
+  render(<MavenView />);
+  expect(screen.getAllByText("first")).toHaveLength(2);
+  expect(screen.getAllByText("second")).toHaveLength(2);
+  const profiles = screen.getAllByRole("checkbox", { name: "local" });
+  expect(profiles).toHaveLength(2);
+  vi.useFakeTimers();
+  await act(async () => {
+    fireEvent.click(profiles[1]!);
+  });
+  expect(profiles[0]).not.toBeChecked();
+  expect(profiles[1]).toBeChecked();
+  await act(async () => {
+    await vi.advanceTimersByTimeAsync(PROFILE_RELOAD_DELAY_MS);
+  });
+  expect(mocks.sync).toHaveBeenCalledWith("maven", expect.any(Number), false, ["local"], members[1], expect.anything());
+  const runs: RunConfig[] = [];
+  const off = registerAction({
+    id: "run.runConfig",
+    title: "Run",
+    hidden: true,
+    run: ({ arg }) => {
+      runs.push((arg as { config: RunConfig }).config);
+    },
+  });
+  await act(async () => {
+    fireEvent.doubleClick(screen.getAllByText("validate")[1]!);
+  });
+  expect(executeBuildLine("maven", "validate", maven.projects[0]!.pom)).toBe(true);
+  off();
+  expect(runs[0]).toMatchObject({ cwd: members[1], command: `${members[1]}/mvnw`, args: ["validate", "-Plocal"] });
+  expect(runs[1]).toMatchObject({ cwd: members[0], command: `${members[0]}/mvnw`, args: ["validate"] });
+});
+
+it("reloads all Maven members with their own profile choices", async () => {
+  vi.useFakeTimers();
+  setProfile(model.maven!.profiles[0]!, true);
+  setProfile(model.maven!.profiles[1]!, true);
+  await vi.advanceTimersByTimeAsync(PROFILE_RELOAD_DELAY_MS);
+  expect(mocks.sync.mock.calls.map((c) => [c[3], c[4]])).toEqual([
+    [["local"], members[0]],
+    [["local"], members[1]],
+  ]);
+  mocks.sync.mockClear();
+  useBuild.setState((s) => ({
+    settings: {
+      ...s.settings,
+      maven: { ...s.settings.maven, profiles: { [profileKey(model.maven!.profiles[1]!)]: true } },
+    },
+  }));
+  await syncTool("maven");
+  expect(mocks.sync.mock.calls.map((c) => [c[3], c[4]])).toEqual([
+    [[], members[0]],
+    [["local"], members[1]],
+  ]);
+});
+
+it("shows and runs duplicate Gradle tasks with each member's wrapper and refresh directory", async () => {
+  const roots = gradleRoots(model.gradle ?? []);
+  act(() =>
+    useBuild.setState((s) => ({
+      expanded: {
+        ...s.expanded,
+        gradle: expandableKeys(roots, (n) => gradleChildren(n, model.gradle ?? [], [], "/workspace")),
+      },
+    })),
+  );
+  render(<GradleView />);
+  const runs: RunConfig[] = [];
+  const off = registerAction({
+    id: "run.runConfig",
+    title: "Run",
+    hidden: true,
+    run: ({ arg }) => {
+      runs.push((arg as { config: RunConfig }).config);
+    },
+  });
+  await act(async () => {
+    fireEvent.doubleClick(screen.getAllByText("test")[1]!);
+  });
+  off();
+  expect(runs[0]).toMatchObject({ cwd: members[1], command: `${members[1]}/gradlew`, args: ["test"] });
+  await syncTool("gradle", members[1]);
+  expect(mocks.sync).toHaveBeenCalledWith("gradle", expect.any(Number), false, [], members[1], expect.anything());
+});
+
+it("refreshes availability after workspace membership changes and does not load untrusted windows", async () => {
+  mocks.model.mockResolvedValue({ maven: null, gradle: [] });
+  await loadModel();
+  expect(useBuild.getState().model).toEqual({ maven: null, gradle: [] });
+  mocks.model.mockClear();
+  act(() => useProject.setState({ project: { ...useProject.getState().project!, trusted: false } }));
+  await loadModel();
+  expect(mocks.model).not.toHaveBeenCalled();
+  expect(useBuild.getState().model).toBeNull();
+});