diff --git a/app/src-tauri/src/models/app_settings.rs b/app/src-tauri/src/models/app_settings.rs
index 26758f9..18ffa3a 100644
--- a/app/src-tauri/src/models/app_settings.rs
+++ b/app/src-tauri/src/models/app_settings.rs
@@ -1,6 +1,7 @@
 use serde::{Deserialize, Serialize};
 
 use super::gateway_settings::GatewaySettings;
+use super::marketplace::{Marketplace, MarketplaceAccount, MarketplaceInstall};
 use super::project::{ClaudeCodeSettings, EnvVar};
 
 fn default_true() -> bool {
@@ -135,6 +136,16 @@ pub struct AppSettings {
     pub gateway: GatewaySettings,
     #[serde(default)]
     pub global_claude_code_settings: Option<ClaudeCodeSettings>,
+    /// Sign-in accounts for private marketplace repos. Secrets live in the
+    /// OS keychain (`storage::secure::*_marketplace_token`), never here.
+    #[serde(default)]
+    pub marketplace_accounts: Vec<MarketplaceAccount>,
+    /// Marketplace git repos the user added.
+    #[serde(default)]
+    pub marketplaces: Vec<Marketplace>,
+    /// Items installed for every project (projects may opt out per item).
+    #[serde(default)]
+    pub global_marketplace_installs: Vec<MarketplaceInstall>,
     /// Whether the terminal loads `@xterm/addon-webgl`.
     ///
     /// `None` is "auto", and auto is not the same answer on every platform.
@@ -246,6 +257,9 @@ impl Default for AppSettings {
             stt: SttSettings::default(),
             gateway: GatewaySettings::default(),
             global_claude_code_settings: None,
+            marketplace_accounts: Vec::new(),
+            marketplaces: Vec::new(),
+            global_marketplace_installs: Vec::new(),
             terminal_gpu_rendering: None,
         }
     }
diff --git a/app/src-tauri/src/models/marketplace.rs b/app/src-tauri/src/models/marketplace.rs
new file mode 100644
index 0000000..d409983
--- /dev/null
+++ b/app/src-tauri/src/models/marketplace.rs
@@ -0,0 +1,399 @@
+//! Marketplace data model — see `docs/superpowers/specs/2026-09-27-marketplace-design.md`.
+//!
+//! Plain data plus the pure rules that decide what a project actually gets
+//! ([`effective_installs`]) and what names are allowed to reach a container
+//! path ([`is_valid_item_key`], [`marketplace_slug`]).
+
+use std::collections::BTreeMap;
+
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub enum ItemKind {
+    Agent,
+    Skill,
+    Command,
+    Hook,
+    Plugin,
+}
+
+impl ItemKind {
+    /// The lowercase name used in report strings (`"agent:code-reviewer"`) and the manifest.
+    pub fn as_str(&self) -> &'static str {
+        match self {
+            ItemKind::Agent => "agent",
+            ItemKind::Skill => "skill",
+            ItemKind::Command => "command",
+            ItemKind::Hook => "hook",
+            ItemKind::Plugin => "plugin",
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub enum AccountMethod {
+    GhHost,
+    GhContainer,
+    Token,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct MarketplaceAccount {
+    pub id: String,
+    pub label: String,
+    pub host: String,
+    pub method: AccountMethod,
+    #[serde(default)]
+    pub username: Option<String>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct Marketplace {
+    pub id: String,
+    pub name: String,
+    pub url: String,
+    #[serde(default)]
+    pub branch: Option<String>,
+    #[serde(default)]
+    pub account_id: Option<String>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash, PartialOrd, Ord, Serialize, Deserialize)]
+pub struct MarketplaceItemRef {
+    pub marketplace_id: String,
+    pub kind: ItemKind,
+    pub key: String,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct MarketplaceInstall {
+    pub marketplace_id: String,
+    pub kind: ItemKind,
+    pub key: String,
+    pub commit: String,
+}
+
+impl MarketplaceInstall {
+    pub fn item_ref(&self) -> MarketplaceItemRef {
+        MarketplaceItemRef {
+            marketplace_id: self.marketplace_id.clone(),
+            kind: self.kind,
+            key: self.key.clone(),
+        }
+    }
+}
+
+/// What a project's container actually gets: the global installs minus the
+/// ones this project opted out of, plus the project's own installs. When the
+/// project installs an item that is also global, the project's entry (and so
+/// its pin) wins. Sorted by item ref so the result is deterministic.
+pub fn effective_installs(
+    global: &[MarketplaceInstall],
+    disabled: &[MarketplaceItemRef],
+    project: &[MarketplaceInstall],
+) -> Vec<MarketplaceInstall> {
+    let mut out: BTreeMap<MarketplaceItemRef, MarketplaceInstall> = BTreeMap::new();
+    for install in global {
+        let item = install.item_ref();
+        if disabled.contains(&item) {
+            continue;
+        }
+        out.insert(item, install.clone());
+    }
+    for install in project {
+        out.insert(install.item_ref(), install.clone());
+    }
+    out.into_values().collect()
+}
+
+/// `^[A-Za-z0-9][A-Za-z0-9._-]{0,63}$` — the only names that may become a
+/// container path component. No `/`, no leading `.` or `-`, no shell
+/// metacharacters.
+pub fn is_valid_item_key(key: &str) -> bool {
+    let bytes = key.as_bytes();
+    if bytes.is_empty() || bytes.len() > 64 {
+        return false;
+    }
+    if !bytes[0].is_ascii_alphanumeric() {
+        return false;
+    }
+    bytes
+        .iter()
+        .all(|b| b.is_ascii_alphanumeric() || matches!(b, b'.' | b'_' | b'-'))
+}
+
+/// A container-safe, collision-free name for a marketplace: its name
+/// lowercased to `[a-z0-9-]`, dashes collapsed, at most 32 characters, then
+/// `-` and the first 8 characters of its id. An empty sanitised name becomes
+/// `marketplace`.
+pub fn marketplace_slug(name: &str, id: &str) -> String {
+    let mut base = String::new();
+    for c in name.chars() {
+        let c = c.to_ascii_lowercase();
+        if c.is_ascii_lowercase() || c.is_ascii_digit() {
+            base.push(c);
+        } else if !base.ends_with('-') && !base.is_empty() {
+            base.push('-');
+        }
+    }
+    let mut base: String = base.trim_matches('-').chars().take(32).collect();
+    while base.ends_with('-') {
+        base.pop();
+    }
+    if base.is_empty() {
+        base.push_str("marketplace");
+    }
+    let id_part: String = id
+        .chars()
+        .filter(|c| c.is_ascii_alphanumeric())
+        .map(|c| c.to_ascii_lowercase())
+        .take(8)
+        .collect();
+    format!("{}-{}", base, id_part)
+}
+
+/// A full, lowercase, 40-character hex object id.
+pub fn is_valid_commit(commit: &str) -> bool {
+    commit.len() == 40
+        && commit
+            .bytes()
+            .all(|b| b.is_ascii_digit() || (b'a'..=b'f').contains(&b))
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct CatalogItem {
+    pub kind: ItemKind,
+    pub key: String,
+    pub name: String,
+    pub description: String,
+    /// Repo-relative path of the item (file or folder).
+    pub path: String,
+    /// `Some(reason)` when the item cannot be installed.
+    pub invalid: Option<String>,
+    /// Hooks only: rendered commands with `${HOOK_DIR}` substituted.
+    #[serde(default)]
+    pub hook_commands: Vec<String>,
+    /// Agents/commands/skills: the markdown body (≤ 64 KiB, truncated);
+    /// plugins: a component listing.
+    #[serde(default)]
+    pub preview: String,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, Default)]
+pub struct MarketplaceSnapshot {
+    pub marketplace_id: String,
+    pub head_commit: Option<String>,
+    /// RFC 3339.
+    pub fetched_at: Option<String>,
+    pub fetch_error: Option<String>,
+    pub items: Vec<CatalogItem>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct ItemUpdate {
+    pub item: MarketplaceItemRef,
+    pub pinned: String,
+    pub head: String,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub enum FileChange {
+    Added,
+    Removed,
+    Modified,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct FileDiff {
+    pub path: String,
+    pub change: FileChange,
+    /// Unified diff text; `None` when either side is binary.
+    pub unified: Option<String>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, Default)]
+pub struct SkippedItem {
+    pub item: String,
+    pub reason: String,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, Default)]
+pub struct SyncReport {
+    #[serde(default)]
+    pub installed: Vec<String>,
+    #[serde(default)]
+    pub updated: Vec<String>,
+    #[serde(default)]
+    pub removed: Vec<String>,
+    #[serde(default)]
+    pub skipped: Vec<SkippedItem>,
+    #[serde(default)]
+    pub errors: Vec<String>,
+    /// RFC 3339, set by the host.
+    #[serde(default)]
+    pub finished_at: String,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(tag = "type", rename_all = "snake_case")]
+pub enum InstallScope {
+    Global,
+    Project { project_id: String },
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct ProjectSyncResult {
+    pub project_id: String,
+    pub report: SyncReport,
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn install(market: &str, kind: ItemKind, key: &str, commit: &str) -> MarketplaceInstall {
+        MarketplaceInstall {
+            marketplace_id: market.to_string(),
+            kind,
+            key: key.to_string(),
+            commit: commit.to_string(),
+        }
+    }
+
+    #[test]
+    fn effective_set_is_global_minus_disabled_plus_project() {
+        let global = vec![
+            install("m1", ItemKind::Agent, "reviewer", "a"),
+            install("m1", ItemKind::Hook, "notify", "a"),
+        ];
+        let disabled = vec![MarketplaceItemRef {
+            marketplace_id: "m1".into(),
+            kind: ItemKind::Hook,
+            key: "notify".into(),
+        }];
+        let project = vec![install("m2", ItemKind::Skill, "tidy", "b")];
+
+        let got = effective_installs(&global, &disabled, &project);
+
+        assert_eq!(
+            got,
+            vec![
+                install("m1", ItemKind::Agent, "reviewer", "a"),
+                install("m2", ItemKind::Skill, "tidy", "b"),
+            ]
+        );
+    }
+
+    #[test]
+    fn project_pin_wins_over_global_pin() {
+        let global = vec![install("m1", ItemKind::Agent, "reviewer", "old")];
+        let project = vec![install("m1", ItemKind::Agent, "reviewer", "new")];
+        let got = effective_installs(&global, &[], &project);
+        assert_eq!(got, vec![install("m1", ItemKind::Agent, "reviewer", "new")]);
+    }
+
+    #[test]
+    fn same_key_different_kind_are_different_items() {
+        let global = vec![
+            install("m1", ItemKind::Agent, "x", "a"),
+            install("m1", ItemKind::Command, "x", "a"),
+        ];
+        assert_eq!(effective_installs(&global, &[], &[]).len(), 2);
+    }
+
+    #[test]
+    fn item_keys_follow_the_pattern() {
+        for ok in ["a", "code-reviewer", "A.b_c-9", &"x".repeat(64)] {
+            assert!(is_valid_item_key(ok), "{ok} should be valid");
+        }
+        for bad in [
+            "",
+            ".hidden",
+            "-flag",
+            "_x",
+            "a/b",
+            "a b",
+            "a;rm",
+            "$(x)",
+            "ä",
+            "..",
+            &"x".repeat(65),
+        ] {
+            assert!(!is_valid_item_key(bad), "{bad:?} should be invalid");
+        }
+    }
+
+    #[test]
+    fn slug_is_sanitised_and_suffixed_with_the_id() {
+        assert_eq!(
+            marketplace_slug("Triple-C  Marketplace!", "1A2B3C4D-ffff"),
+            "triple-c-marketplace-1a2b3c4d"
+        );
+        assert_eq!(
+            marketplace_slug("***", "abcdef0123"),
+            "marketplace-abcdef01"
+        );
+        let long = marketplace_slug(&"x".repeat(80), "12345678");
+        assert_eq!(long, format!("{}-12345678", "x".repeat(32)));
+    }
+
+    #[test]
+    fn commits_must_be_full_lowercase_hex() {
+        assert!(is_valid_commit(&"a".repeat(40)));
+        assert!(!is_valid_commit(&"A".repeat(40)));
+        assert!(!is_valid_commit(&"a".repeat(39)));
+        assert!(!is_valid_commit("HEAD"));
+    }
+
+    #[test]
+    fn install_scope_serialises_tagged() {
+        assert_eq!(
+            serde_json::to_value(InstallScope::Global).unwrap(),
+            serde_json::json!({"type": "global"})
+        );
+        assert_eq!(
+            serde_json::to_value(InstallScope::Project {
+                project_id: "p".into()
+            })
+            .unwrap(),
+            serde_json::json!({"type": "project", "project_id": "p"})
+        );
+    }
+
+    #[test]
+    fn kinds_serialise_snake_case() {
+        assert_eq!(serde_json::to_value(ItemKind::Plugin).unwrap(), "plugin");
+        assert_eq!(
+            serde_json::to_value(AccountMethod::GhHost).unwrap(),
+            "gh_host"
+        );
+    }
+
+    #[test]
+    fn settings_and_projects_saved_before_the_marketplace_still_load() {
+        let mut settings = serde_json::to_value(crate::models::AppSettings::default()).unwrap();
+        for key in [
+            "marketplace_accounts",
+            "marketplaces",
+            "global_marketplace_installs",
+        ] {
+            settings.as_object_mut().unwrap().remove(key);
+        }
+        let settings: crate::models::AppSettings = serde_json::from_value(settings).unwrap();
+        assert!(settings.marketplace_accounts.is_empty());
+        assert!(settings.marketplaces.is_empty());
+        assert!(settings.global_marketplace_installs.is_empty());
+
+        let mut project =
+            serde_json::to_value(crate::models::Project::new("p".to_string(), Vec::new())).unwrap();
+        for key in ["marketplace_installs", "marketplace_disabled"] {
+            project.as_object_mut().unwrap().remove(key);
+        }
+        let project: crate::models::Project = serde_json::from_value(project).unwrap();
+        assert!(project.marketplace_installs.is_empty());
+        assert!(project.marketplace_disabled.is_empty());
+    }
+}
diff --git a/app/src-tauri/src/models/mod.rs b/app/src-tauri/src/models/mod.rs
index 10e2c0f..9935ee4 100644
--- a/app/src-tauri/src/models/mod.rs
+++ b/app/src-tauri/src/models/mod.rs
@@ -1,6 +1,7 @@
 pub mod app_settings;
 pub mod container_config;
 pub mod gateway_settings;
+pub mod marketplace;
 pub mod migration;
 pub mod note;
 pub mod project;
@@ -10,6 +11,7 @@ pub mod update_info;
 pub use app_settings::*;
 pub use container_config::*;
 pub use gateway_settings::*;
+pub use marketplace::*;
 pub use migration::*;
 pub use note::*;
 pub use project::*;
diff --git a/app/src-tauri/src/models/project.rs b/app/src-tauri/src/models/project.rs
index 0f32161..fb32c34 100644
--- a/app/src-tauri/src/models/project.rs
+++ b/app/src-tauri/src/models/project.rs
@@ -446,6 +446,12 @@ pub struct Project {
     /// User-defined display names for terminal tabs, keyed by session id.
     #[serde(default)]
     pub renamed_session_names: HashMap<String, String>,
+    /// Marketplace items installed for this project only (spec §2).
+    #[serde(default)]
+    pub marketplace_installs: Vec<super::marketplace::MarketplaceInstall>,
+    /// Global marketplace installs this project opts out of.
+    #[serde(default)]
+    pub marketplace_disabled: Vec<super::marketplace::MarketplaceItemRef>,
     pub created_at: String,
     pub updated_at: String,
 }
@@ -693,6 +699,8 @@ impl Project {
             claude_instructions: None,
             claude_code_settings: None,
             renamed_session_names: HashMap::new(),
+            marketplace_installs: Vec::new(),
+            marketplace_disabled: Vec::new(),
             created_at: now.clone(),
             updated_at: now,
         }
@@ -789,7 +797,10 @@ mod tests {
     }
 
     fn env(key: &str, value: &str) -> EnvVar {
-        EnvVar { key: key.to_string(), value: value.to_string() }
+        EnvVar {
+            key: key.to_string(),
+            value: value.to_string(),
+        }
     }
 
     #[test]
@@ -887,7 +898,10 @@ mod tests {
         // `merge_claude_code_settings` spells it. `main` resolved this with
         // `if p.env_scrub { true } else { g.env_scrub }`, i.e. the global won —
         // and it has to go on winning, because the user never turned this off.
-        let global = ClaudeCodeSettings { env_scrub: Some(true), ..Default::default() };
+        let global = ClaudeCodeSettings {
+            env_scrub: Some(true),
+            ..Default::default()
+        };
         assert_eq!(
             stored.env_scrub.or(global.env_scrub),
             Some(true),
@@ -902,7 +916,10 @@ mod tests {
         let json = r#"{ "env_scrub": false }"#;
         let chosen: ClaudeCodeSettings = serde_json::from_str(json).unwrap();
         assert_eq!(chosen.env_scrub, Some(false));
-        let global = ClaudeCodeSettings { env_scrub: Some(true), ..Default::default() };
+        let global = ClaudeCodeSettings {
+            env_scrub: Some(true),
+            ..Default::default()
+        };
         assert_eq!(chosen.env_scrub.or(global.env_scrub), Some(false));
     }
 
@@ -916,7 +933,10 @@ mod tests {
         assert_eq!(json, "{}");
         assert!(!json.contains("null"));
 
-        let partial = ClaudeCodeSettings { env_scrub: Some(false), ..Default::default() };
+        let partial = ClaudeCodeSettings {
+            env_scrub: Some(false),
+            ..Default::default()
+        };
         let json = serde_json::to_string(&partial).unwrap();
         assert_eq!(json, r#"{"env_scrub":false}"#);
         // And it reads back as what it is.
@@ -984,7 +1004,10 @@ mod tests {
         });
         let migrated = Project::migrate_from_value(legacy);
         let obj = migrated.as_object().unwrap();
-        assert!(obj.contains_key("paths"), "the migration should still do its own job");
+        assert!(
+            obj.contains_key("paths"),
+            "the migration should still do its own job"
+        );
         assert!(!obj.contains_key("auth_bridge_enabled"));
         assert!(!obj.contains_key("browser_view_enabled"));
     }
diff --git a/app/src/components/projects/PermissionModeControl.test.tsx b/app/src/components/projects/PermissionModeControl.test.tsx
index 5249904..f1d6d83 100644
--- a/app/src/components/projects/PermissionModeControl.test.tsx
+++ b/app/src/components/projects/PermissionModeControl.test.tsx
@@ -32,6 +32,8 @@ const baseProject: Project = {
   claude_instructions: null,
   claude_code_settings: null,
   renamed_session_names: {},
+  marketplace_installs: [],
+  marketplace_disabled: [],
   created_at: "2026-01-01T00:00:00Z",
   updated_at: "2026-01-01T00:00:00Z",
 };
diff --git a/app/src/components/projects/ProjectRow.test.tsx b/app/src/components/projects/ProjectRow.test.tsx
index ffd6b6e..eae742a 100644
--- a/app/src/components/projects/ProjectRow.test.tsx
+++ b/app/src/components/projects/ProjectRow.test.tsx
@@ -60,6 +60,8 @@ const baseProject: Project = {
   claude_instructions: null,
   claude_code_settings: null,
   renamed_session_names: {},
+  marketplace_installs: [],
+  marketplace_disabled: [],
   created_at: "2026-01-01T00:00:00Z",
   updated_at: "2026-01-01T00:00:00Z",
 };
diff --git a/app/src/components/projects/home/BrowserTab.test.tsx b/app/src/components/projects/home/BrowserTab.test.tsx
index df7624b..649015c 100644
--- a/app/src/components/projects/home/BrowserTab.test.tsx
+++ b/app/src/components/projects/home/BrowserTab.test.tsx
@@ -125,6 +125,8 @@ const project: Project = {
   claude_instructions: null,
   claude_code_settings: null,
   renamed_session_names: {},
+  marketplace_installs: [],
+  marketplace_disabled: [],
   created_at: "2026-01-01T00:00:00Z",
   updated_at: "2026-01-01T00:00:00Z",
 } as unknown as Project;
diff --git a/app/src/components/projects/home/TaskEditorModal.test.tsx b/app/src/components/projects/home/TaskEditorModal.test.tsx
index 62e942e..ad9c62d 100644
--- a/app/src/components/projects/home/TaskEditorModal.test.tsx
+++ b/app/src/components/projects/home/TaskEditorModal.test.tsx
@@ -44,6 +44,8 @@ const baseProject: Project = {
   claude_instructions: null,
   claude_code_settings: null,
   renamed_session_names: {},
+  marketplace_installs: [],
+  marketplace_disabled: [],
   created_at: "2026-01-01T00:00:00Z",
   updated_at: "2026-01-01T00:00:00Z",
 };
diff --git a/app/src/components/projects/home/config/ModelSection.test.tsx b/app/src/components/projects/home/config/ModelSection.test.tsx
index afbd6dd..f61c236 100644
--- a/app/src/components/projects/home/config/ModelSection.test.tsx
+++ b/app/src/components/projects/home/config/ModelSection.test.tsx
@@ -34,6 +34,8 @@ const baseProject: Project = {
   claude_instructions: null,
   claude_code_settings: null,
   renamed_session_names: {},
+  marketplace_installs: [],
+  marketplace_disabled: [],
   created_at: "2026-01-01T00:00:00Z",
   updated_at: "2026-01-01T00:00:00Z",
 };
diff --git a/app/src/components/projects/home/config/RuntimeSection.test.tsx b/app/src/components/projects/home/config/RuntimeSection.test.tsx
index 4733c09..e8e1ea7 100644
--- a/app/src/components/projects/home/config/RuntimeSection.test.tsx
+++ b/app/src/components/projects/home/config/RuntimeSection.test.tsx
@@ -47,6 +47,8 @@ const baseProject: Project = {
   claude_instructions: null,
   claude_code_settings: null,
   renamed_session_names: {},
+  marketplace_installs: [],
+  marketplace_disabled: [],
   created_at: "2026-01-01T00:00:00Z",
   updated_at: "2026-01-01T00:00:00Z",
 };
diff --git a/app/src/components/projects/home/config/WorkspaceSection.test.tsx b/app/src/components/projects/home/config/WorkspaceSection.test.tsx
index a44970b..2f39ad6 100644
--- a/app/src/components/projects/home/config/WorkspaceSection.test.tsx
+++ b/app/src/components/projects/home/config/WorkspaceSection.test.tsx
@@ -39,6 +39,8 @@ const baseProject: Project = {
   claude_instructions: null,
   claude_code_settings: null,
   renamed_session_names: {},
+  marketplace_installs: [],
+  marketplace_disabled: [],
   created_at: "2026-01-01T00:00:00Z",
   updated_at: "2026-01-01T00:00:00Z",
 };
diff --git a/app/src/components/settings/SharedAuthSettings.test.tsx b/app/src/components/settings/SharedAuthSettings.test.tsx
index dae02d7..6ab0a52 100644
--- a/app/src/components/settings/SharedAuthSettings.test.tsx
+++ b/app/src/components/settings/SharedAuthSettings.test.tsx
@@ -72,6 +72,8 @@ const baseProject: Project = {
   claude_instructions: null,
   claude_code_settings: null,
   renamed_session_names: {},
+  marketplace_installs: [],
+  marketplace_disabled: [],
   created_at: "2026-01-01T00:00:00Z",
   updated_at: "2026-01-01T00:00:00Z",
 };
diff --git a/app/src/lib/types.ts b/app/src/lib/types.ts
index 849a5bf..2dcaa33 100644
--- a/app/src/lib/types.ts
+++ b/app/src/lib/types.ts
@@ -66,6 +66,8 @@ export interface Project {
   claude_instructions: string | null;
   claude_code_settings: ClaudeCodeSettings | null;
   renamed_session_names: Record<string, string>;
+  marketplace_installs: MarketplaceInstall[];
+  marketplace_disabled: MarketplaceItemRef[];
   created_at: string;
   updated_at: string;
 }
@@ -296,6 +298,81 @@ export interface AppSettings {
    *  canvas renderer it would otherwise fall back to. See
    *  `resolveTerminalGpuRendering` in `lib/terminalRenderer.ts`. */
   terminal_gpu_rendering: boolean | null;
+  marketplace_accounts: MarketplaceAccount[];
+  marketplaces: Marketplace[];
+  global_marketplace_installs: MarketplaceInstall[];
+}
+
+// ── Marketplace (mirrors src-tauri/src/models/marketplace.rs) ───────────────
+
+export type ItemKind = "agent" | "skill" | "command" | "hook" | "plugin";
+export type AccountMethod = "gh_host" | "gh_container" | "token";
+export interface MarketplaceAccount {
+  id: string;
+  label: string;
+  host: string;
+  method: AccountMethod;
+  username: string | null;
+}
+export interface Marketplace {
+  id: string;
+  name: string;
+  url: string;
+  branch: string | null;
+  account_id: string | null;
+}
+export interface MarketplaceItemRef {
+  marketplace_id: string;
+  kind: ItemKind;
+  key: string;
+}
+export interface MarketplaceInstall extends MarketplaceItemRef {
+  commit: string;
+}
+export interface CatalogItem {
+  kind: ItemKind;
+  key: string;
+  name: string;
+  description: string;
+  path: string;
+  invalid: string | null;
+  hook_commands: string[];
+  preview: string;
+}
+export interface MarketplaceSnapshot {
+  marketplace_id: string;
+  head_commit: string | null;
+  fetched_at: string | null;
+  fetch_error: string | null;
+  items: CatalogItem[];
+}
+export interface ItemUpdate {
+  item: MarketplaceItemRef;
+  pinned: string;
+  head: string;
+}
+export type FileChange = "added" | "removed" | "modified";
+export interface FileDiff {
+  path: string;
+  change: FileChange;
+  unified: string | null;
+}
+export interface SkippedItem {
+  item: string;
+  reason: string;
+}
+export interface SyncReport {
+  installed: string[];
+  updated: string[];
+  removed: string[];
+  skipped: SkippedItem[];
+  errors: string[];
+  finished_at: string;
+}
+export type InstallScope = { type: "global" } | { type: "project"; project_id: string };
+export interface ProjectSyncResult {
+  project_id: string;
+  report: SyncReport;
 }
 
 /** What `preview_settings_import` returns before anything is applied —