style: format code for better readability in tests and function signatures

P1 bugs:
- unix_launcher: shell_split respects quoted args (was split_whitespace)
- plugin-host: 5s timeout on external plugin search
- ui: handle engine init panic, wire error state
- ui-egui: read window config instead of always using defaults
- plugin-url: use OpenPath action instead of SpawnProcess+xdg-open

Architecture:
- remove WindowConfig (mirror of WindowCfg); use WindowCfg directly
- remove on_select closure from SearchResult (domain leakage)
- remove LaunchAction::Custom; add Plugin::on_selected + SearchEngine::on_selected
- apps: record frecency via on_selected instead of embedded closure

Design smells:
- frecency: extract decay_factor helper, write outside mutex
- apps: remove cfg(test) cache_path hack; add new_for_test ctor
- apps: stable ResultId using name+exec to prevent collision
- files: stable ResultId using full path instead of index
- plugin-host: remove k-launcher-os-bridge dep (WindowConfig gone)

.github/workflows/ci.yml

@@ -0,0 +1,39 @@
+name: CI
+
+on:
+  push:
+    branches: [master]
+  pull_request:
+    branches: [master]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+      - uses: Swatinem/rust-cache@v2
+      - name: Install system deps
+        run: sudo apt-get install -y libwayland-dev libxkbcommon-dev pkg-config
+      - run: cargo test --workspace
+
+  clippy:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          components: clippy
+      - uses: Swatinem/rust-cache@v2
+      - name: Install system deps
+        run: sudo apt-get install -y libwayland-dev libxkbcommon-dev pkg-config
+      - run: cargo clippy --workspace -- -D warnings
+
+  fmt:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          components: rustfmt
+      - run: cargo fmt --check

.github/workflows/release.yml

@@ -0,0 +1,21 @@
+name: Release
+
+on:
+  push:
+    tags:
+      - 'v*'
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+      - uses: Swatinem/rust-cache@v2
+      - name: Install system deps
+        run: sudo apt-get install -y libwayland-dev libxkbcommon-dev pkg-config
+      - run: cargo build --release
+      - uses: actions/upload-artifact@v4
+        with:
+          name: k-launcher
+          path: target/release/k-launcher

.gitignore

@@ -1 +1,2 @@
 target/
+.worktrees/

ARCHITECTURE.md

@@ -0,0 +1,110 @@
+# k-launcher Architecture
+
+## Philosophy
+
+- **TDD:** Red-Green-Refactor is mandatory. No functional code without a failing test first.
+- **Clean Architecture:** Strict layer separation — Domain, Application, Infrastructure, Main.
+- **Newtype Pattern:** All domain primitives wrapped (e.g. `struct Score(f64)`).
+- **Small Traits / ISP:** Many focused traits over one "God" trait.
+- **No Cyclic Dependencies:** Use IoC (define traits in higher-level modules, implement in lower-level).
+
+---
+
+## Workspace Structure
+
+| Crate | Layer | Responsibility |
+|---|---|---|
+| `k-launcher-kernel` | Domain + Application | Newtypes (`ResultId`, `ResultTitle`, `Score`), `Plugin` trait, `SearchEngine` trait, `AppLauncher` port, `Kernel` use case |
+| `k-launcher-config` | Infrastructure | TOML config loading; `Config`, `WindowCfg`, `AppearanceCfg`, `PluginsCfg` structs |
+| `k-launcher-os-bridge` | Infrastructure | `UnixAppLauncher` (process spawning), `WindowConfig` adapter |
+| `k-launcher-plugin-host` | Infrastructure | `ExternalPlugin` — JSON-newline IPC protocol for out-of-process plugins |
+| `k-launcher-ui` | Infrastructure | iced 0.14 Elm-like UI (`KLauncherApp`, debounced async search, keyboard nav) |
+| `k-launcher-ui-egui` | Infrastructure | Alternative egui UI (feature-gated) |
+| `plugins/plugin-apps` | Infrastructure | XDG `.desktop` parser, frecency scoring, nucleo fuzzy matching |
+| `plugins/plugin-calc` | Infrastructure | `evalexpr`-based calculator |
+| `plugins/plugin-cmd` | Infrastructure | Shell command runner |
+| `plugins/plugin-files` | Infrastructure | File path search |
+| `plugins/plugin-url` | Infrastructure | URL opener |
+| `k-launcher` | Main/Entry | DI wiring, CLI arg parsing (`show` command), `run_ui()` composition root |
+
+---
+
+## Dependency Graph
+
+```
+k-launcher (main)
+  ├── k-launcher-kernel        (Domain/Application)
+  ├── k-launcher-config        (Infrastructure — pure data, no kernel dep)
+  ├── k-launcher-os-bridge     (Infrastructure)
+  ├── k-launcher-plugin-host   (Infrastructure)
+  ├── k-launcher-ui            (Infrastructure)
+  └── plugins/*                (Infrastructure)
+       └── k-launcher-kernel
+```
+
+All arrows point inward toward the kernel. The kernel has no external dependencies.
+
+---
+
+## Core Abstractions (kernel)
+
+```rust
+// Plugin trait — implemented by every plugin
+async fn search(&self, query: &str) -> Vec<SearchResult>;
+
+// SearchEngine trait — implemented by Kernel
+async fn search(&self, query: &str) -> Vec<SearchResult>;
+
+// AppLauncher port — implemented by UnixAppLauncher in os-bridge
+fn execute(&self, action: &LaunchAction);
+
+// DesktopEntrySource trait (plugin-apps) — swappable .desktop file source
+```
+
+---
+
+## Plugin System
+
+Two kinds of plugins:
+
+1. **In-process** — implement `Plugin` in Rust, linked at compile time.
+   - `plugin-calc`, `plugin-apps`, `plugin-cmd`, `plugin-files`, `plugin-url`
+
+2. **External / out-of-process** — `ExternalPlugin` in `k-launcher-plugin-host` communicates via JSON newline protocol over stdin/stdout.
+   - Query: `{"query": "..."}`
+   - Response: `[{"id": "...", "title": "...", "score": 1.0, "description": "...", "icon": "...", "action": "..."}]`
+
+Plugins are enabled/disabled via `~/.config/k-launcher/config.toml`.
+
+---
+
+## Kernel (Application Use Case)
+
+`Kernel::search` fans out to all registered plugins concurrently via `join_all`, merges results, sorts by `Score` descending, truncates to `max_results`.
+
+---
+
+## UI Architecture (iced 0.14 — Elm model)
+
+- **State:** `KLauncherApp` holds engine ref, launcher ref, query string, results, selected index, appearance config.
+- **Messages:** `QueryChanged`, `ResultsReady`, `KeyPressed`
+- **Update:**
+  - `QueryChanged` → spawns debounced async task (50 ms) → `ResultsReady`
+  - Epoch guard prevents stale results from out-of-order responses
+- **View:** search bar + scrollable result list with icon support (SVG/raster)
+- **Subscription:** keyboard events — `Esc` = quit, `Enter` = launch, arrows = navigate
+- **Window:** transparent, undecorated, centered (Wayland-compatible)
+
+---
+
+## Frecency (plugin-apps)
+
+`FrecencyStore` records app launches by ID. On empty query, returns top-5 frecent apps instead of search results.
+
+---
+
+## Configuration
+
+`~/.config/k-launcher/config.toml` — sections: `[window]`, `[appearance]`, `[search]`, `[plugins]`.
+
+All fields have sane defaults; a missing file yields defaults without error.

CLAUDE.md

@@ -0,0 +1,58 @@
+## 1. Core Philosophy
+
+- **Test-Driven Development (TDD):** No functional code is written without a failing test first. Red-Green-Refactor is the mandatory cycle.
+- **Clean Architecture:** Maintain strict separation between Domain, Application, and Infrastructure layers.
+- **Newtype Pattern:** Use the "Newtype" pattern for all domain primitives (e.g., `struct UserId(Uuid)`) to ensure type safety and prevent primitive obsession.
+
+---
+
+## 2. Structural Rules
+
+### Dependency Management
+
+- **Strict Unidirectionality:** Dependencies must only point inwards (towards the Domain).
+- **No Cyclic Dependencies:** Use traits and Dependency Injection (DI) to break cycles. If two modules need each other, abstract the shared behavior into a trait or move common data to a lower-level module.
+- **Feature Gating:** Organize the project into logical crates or modules that can be compiled independently.
+
+### Traits and Decoupling
+
+- **Swappable Infrastructure:** Define all external interactions (Database, API, File System) as traits in the Application layer.
+- **Small Traits:** Adhere to the Interface Segregation Principle. Favor many specific traits over one "God" trait.
+- **Mocking:** Use traits to allow easy mocking in unit tests without requiring a real database or network.
+
+---
+
+## 3. Rust Specifics & Clean Code
+
+### Type Safety
+
+- Avoid `String` or `i32` for domain concepts. Wrap them in structs.
+- Use `Result` and `Option` explicitly. Minimize `unwrap()` and `expect()`—handle errors gracefully at the boundaries.
+
+### Formatting & Style
+
+- Follow standard `rustfmt` and `clippy` suggestions.
+- Function names should be descriptive (e.g., `process_valid_order` instead of `handle_data`).
+- Keep functions small (typically under 20-30 lines).
+
+---
+
+## 4. Layer Definitions
+
+| Layer              | Responsibility                                | Allowed Dependencies |
+| ------------------ | --------------------------------------------- | -------------------- |
+| **Domain**         | Pure Business Logic, Entities, Value Objects. | None (Pure Rust)     |
+| **Application**    | Use Cases, Orchestration, Trait definitions.  | Domain               |
+| **Infrastructure** | Trait implementations (DB, HTTP clients).     | Domain, Application  |
+| **Main/API**       | Entry point, Wire-up/DI, Routing.             | All of the above     |
+
+---
+
+## 5. TDD Workflow Requirement
+
+1. **Write a Test:** Create a test in `src/lib.rs` or a `tests/` directory.
+2. **Define the Interface:** Use a trait or function signature to make the test compile (but fail).
+3. **Minimum Implementation:** Write just enough code to pass the test.
+4. **Refactor:** Clean up the logic, ensure no duplication, and check for "Newtype" opportunities.
+
+> **Note on Cyclic Dependencies:** If an AI agent suggests a change that introduces a cycle, it must be rejected. Use **Inversion of Control** by defining a trait in the higher-level module that the lower-level module implements.

Cargo.toml

@@ -1,19 +1,41 @@
 [workspace]
 members = [
     "crates/k-launcher",
+    "crates/k-launcher-config",
     "crates/k-launcher-kernel",
     "crates/k-launcher-os-bridge",
+    "crates/k-launcher-plugin-host",
     "crates/k-launcher-ui",
     "crates/plugins/plugin-apps",
     "crates/plugins/plugin-calc",
+    "crates/plugins/plugin-cmd",
     "crates/plugins/plugin-files",
+    "crates/k-launcher-ui-egui",
+    "crates/plugins/plugin-url",
+]
+default-members = [
+    "crates/k-launcher",
+    "crates/k-launcher-config",
+    "crates/k-launcher-kernel",
+    "crates/k-launcher-os-bridge",
+    "crates/k-launcher-plugin-host",
+    "crates/k-launcher-ui",
+    "crates/plugins/plugin-apps",
+    "crates/plugins/plugin-calc",
+    "crates/plugins/plugin-cmd",
+    "crates/plugins/plugin-files",
+    "crates/plugins/plugin-url",
 ]
 resolver = "2"
 
 [workspace.dependencies]
 async-trait = "0.1"
+bincode = { version = "2", features = ["serde"] }
+dirs = "6.0"
 futures = "0.3"
-iced = { version = "0.14", features = ["image", "svg", "tokio", "tiny-skia"] }
+iced = { version = "0.14", default-features = false, features = ["image", "svg", "tokio", "tiny-skia", "wayland", "x11", "crisp", "web-colors", "thread-pool"] }
 serde = { version = "1.0", features = ["derive"] }
+serde_json = "1"
 tokio = { version = "1.35", features = ["rt-multi-thread", "macros"] }
+toml = "1.0"
 tracing = "0.1"

Makefile

@@ -0,0 +1,44 @@
+.PHONY: build build-egui dev check clippy fmt fmt-check test run run-egui install install-egui clean
+
+RELEASE_BIN := target/release/k-launcher
+EGUI_BIN    := target/release/k-launcher-egui
+INSTALL_DIR := $(HOME)/.local/bin
+
+build:
+	cargo build --release
+
+build-egui:
+	cargo build --release -p k-launcher --features egui --bin k-launcher-egui
+
+dev:
+	cargo build
+
+check:
+	cargo check --workspace
+
+clippy:
+	cargo clippy --workspace -- -D warnings
+
+fmt:
+	cargo fmt --all
+
+fmt-check:
+	cargo fmt --all -- --check
+
+test:
+	cargo test --workspace
+
+run:
+	cargo run --release
+
+run-egui:
+	cargo run --release -p k-launcher --features egui --bin k-launcher-egui
+
+install: build
+	install -Dm755 $(RELEASE_BIN) $(INSTALL_DIR)/k-launcher
+
+install-egui: build-egui
+	install -Dm755 $(EGUI_BIN) $(INSTALL_DIR)/k-launcher-egui
+
+clean:
+	cargo clean

README.md

@@ -1,56 +1,69 @@
-# K-Launcher
+# k-launcher
 
-K-Launcher is a lightweight, GPU-accelerated command palette for Linux (Wayland/X11), macOS, and Windows. It reimagines the "Spotlight" experience through the lens of Frutiger Aero—focusing on gloss, glass, and skeuomorphism—powered by a non-blocking, multi-threaded Rust kernel.
+A lightweight, GPU-accelerated command palette for Linux (Wayland/X11). Zero Electron — every pixel rendered via WGPU. Async search that never blocks the UI.
 
-## Core Philosophy
+## Quick Start
 
-- Zero Webview: No Chromium, no Electron. Every pixel is rendered via WGPU (Iced) for sub-5ms input-to-render latency.
+```bash
-
+git clone https://github.com/GKaszewski/k-launcher
-- Async-First: Search queries never block the UI. If the file-searcher is indexing, the calculator still feels instant.
+cd k-launcher
-
+cargo build --release
-- The "Aero" Standard: Deep support for Gaussian blur (via Layer Shell), linear gradients, and high-gloss textures.
+./target/release/k-launcher
-
-## High-Level Architecture
-
-We are utilizing a "Hub-and-Spoke" model within a Cargo Workspace. The k-launcher-kernel acts as the central hub, dispatching user input to various "Spokes" (Plugins).
-
-### The Crate Hierarchy
-
-| Crate                      | Responsibility                                            | Key Dependencies                       |
-| -------------------------- | --------------------------------------------------------- | -------------------------------------- |
-| **`k-launcher`**           | The entry-point binary. Glues everything together.        | `k-launcher-ui`, `k-launcher-kernel`   |
-| **`k-launcher-ui`**        | The Iced-based view layer. Handles animations/theming.    | `iced`, `lyon` (for vector paths)      |
-| **`k-launcher-kernel`**    | The "Brain." Manages state, history, and plugin dispatch. | `tokio`, `tracing`                     |
-| **`k-launcher-os-bridge`** | OS-specific windowing (Layer Shell for Wayland, Win32).   | `iced_layershell`, `raw-window-handle` |
-| **`plugins/*`**            | Individual features (Calc, Files, Apps, Web).             | `plugin-api` (Shared traits)           |
-
-## Data & Communication Flow
-
-K-Launcher operates on an Event loop.
-
-```
-sequenceDiagram
-    participant User
-    participant UI as k-launcher-ui
-    participant Kernel as k-launcher-kernel
-    participant Plugins as plugin-file-search
-
-    User->>UI: Types "p"
-    UI->>Kernel: QueryUpdate("p")
-    par Parallel Search
-        Kernel->>Plugins: async search("p")
-        Plugins-->>Kernel: List<SearchResult>
-    end
-    Kernel->>UI: NewResults(Vec)
-    UI-->>User: Render Glass Result List
 ```
 
-## Technical Specifications
+## Keybinds
 
-To ensure "Plug and Play" capability, all features must implement the `Plugin` trait. This allows the user to swap the default `file-searcher` for something like `fzf` or `plocate` without recompiling the UI.
+| Key       | Action          |
+| --------- | --------------- |
+| Type      | Filter results  |
+| `↑` / `↓` | Navigate        |
+| `Enter`   | Launch selected |
+| `Escape`  | Close           |
 
-To achieve the 2000s aesthetic without a browser:
+## Compositor Setup
 
-- Background Blur: On Wayland, we request blur through the org_kde_kwin_blur or fractional-scale protocols.
+k-launcher uses a normal window; configure your compositor to float it.
-- Shaders: We will use Iced’s canvas to draw glossy "shine" overlays that respond to mouse hovering.
+
-- Icons: We will prefer .svg and .png with high-depth shadows over flat icon fonts.
+**Hyprland** (`~/.config/hypr/hyprland.conf`):
+
+```
+windowrule = float, ^(k-launcher)$
+windowrule = center, ^(k-launcher)$
+bind = SUPER, Space, exec, k-launcher
+```
+
+**Sway** (`~/.config/sway/config`):
+
+```
+for_window [app_id="k-launcher"] floating enable, move position center
+bindsym Mod4+space exec k-launcher
+```
+
+## Built-in Plugins
+
+| Trigger           | Plugin | Example        |
+| ----------------- | ------ | -------------- |
+| (any text)        | Apps   | `firefox`      |
+| number/expression | Calc   | `2^10 + 5`     |
+| `>` prefix        | Shell  | `> echo hello` |
+| `/` or `~/`       | Files  | `~/Documents`  |
+
+## External Plugins
+
+Drop in community plugins — any language, no recompilation. Plugins are executables that communicate over stdin/stdout JSON:
+
+```toml
+# ~/.config/k-launcher/config.toml
+[[plugins.external]]
+name = "my-plugin"
+path = "/usr/lib/k-launcher/plugins/my-plugin"
+```
+
+See [Plugin Development](docs/plugin-development.md) for the full protocol.
+
+## Docs
+
+- [Installation](docs/install.md)
+- [Usage & Keybinds](docs/usage.md)
+- [Configuration & Theming](docs/configuration.md)
+- [Plugin Development](docs/plugin-development.md)

crates/k-launcher-config/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "k-launcher-config"
+version = "0.1.0"
+edition = "2024"
+
+[lib]
+name = "k_launcher_config"
+path = "src/lib.rs"
+
+[dependencies]
+dirs = { workspace = true }
+serde = { workspace = true }
+toml = { workspace = true }

crates/k-launcher-config/src/lib.rs

@@ -0,0 +1,191 @@
+use serde::Deserialize;
+
+// RGBA: [r, g, b, a] where r/g/b are 0–255 as f32, a is 0.0–1.0
+pub type Rgba = [f32; 4];
+
+#[derive(Debug, Clone, Deserialize, Default)]
+#[serde(default)]
+pub struct Config {
+    pub window: WindowCfg,
+    pub appearance: AppearanceCfg,
+    pub search: SearchCfg,
+    pub plugins: PluginsCfg,
+}
+
+#[derive(Debug, Clone, Deserialize)]
+#[serde(default)]
+pub struct WindowCfg {
+    pub width: f32,
+    pub height: f32,
+    pub decorations: bool,
+    pub transparent: bool,
+    pub resizable: bool,
+}
+
+impl Default for WindowCfg {
+    fn default() -> Self {
+        Self {
+            width: 600.0,
+            height: 400.0,
+            decorations: false,
+            transparent: true,
+            resizable: false,
+        }
+    }
+}
+
+#[derive(Debug, Clone, Deserialize)]
+#[serde(default)]
+pub struct AppearanceCfg {
+    pub background_rgba: Rgba,
+    pub border_rgba: Rgba,
+    pub border_width: f32,
+    pub border_radius: f32,
+    pub search_font_size: f32,
+    pub title_size: f32,
+    pub desc_size: f32,
+    pub row_radius: f32,
+    pub placeholder: String,
+}
+
+impl Default for AppearanceCfg {
+    fn default() -> Self {
+        Self {
+            background_rgba: [20.0, 20.0, 30.0, 0.9],
+            border_rgba: [229.0, 125.0, 33.0, 1.0],
+            border_width: 1.0,
+            border_radius: 8.0,
+            search_font_size: 18.0,
+            title_size: 15.0,
+            desc_size: 12.0,
+            row_radius: 4.0,
+            placeholder: "Search...".to_string(),
+        }
+    }
+}
+
+#[derive(Debug, Clone, Deserialize)]
+#[serde(default)]
+pub struct SearchCfg {
+    pub max_results: usize,
+}
+
+impl Default for SearchCfg {
+    fn default() -> Self {
+        Self { max_results: 8 }
+    }
+}
+
+#[derive(Debug, Clone, Deserialize, Default)]
+pub struct ExternalPluginCfg {
+    pub name: String,
+    pub path: String,
+    #[serde(default)]
+    pub args: Vec<String>,
+}
+
+#[derive(Debug, Clone, Deserialize)]
+#[serde(default)]
+pub struct PluginsCfg {
+    pub calc: bool,
+    pub cmd: bool,
+    pub files: bool,
+    pub apps: bool,
+    pub external: Vec<ExternalPluginCfg>,
+}
+
+impl Default for PluginsCfg {
+    fn default() -> Self {
+        Self {
+            calc: true,
+            cmd: true,
+            files: true,
+            apps: true,
+            external: vec![],
+        }
+    }
+}
+
+pub fn load() -> Config {
+    let path = dirs::config_dir().map(|d| d.join("k-launcher").join("config.toml"));
+    let Some(path) = path else {
+        return Config::default();
+    };
+    let Ok(content) = std::fs::read_to_string(&path) else {
+        return Config::default();
+    };
+    toml::from_str(&content).unwrap_or_default()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn default_config_has_sane_values() {
+        let cfg = Config::default();
+        assert_eq!(cfg.search.max_results, 8);
+        assert_eq!(cfg.window.width, 600.0);
+        assert_eq!(cfg.window.height, 400.0);
+        assert!(!cfg.window.decorations);
+        assert!(cfg.window.transparent);
+        assert!(!cfg.window.resizable);
+        assert!(cfg.plugins.calc);
+        assert!(cfg.plugins.apps);
+        assert_eq!(cfg.appearance.search_font_size, 18.0);
+        assert_eq!(cfg.appearance.placeholder, "Search...");
+    }
+
+    #[test]
+    fn parse_partial_toml_uses_defaults() {
+        let toml = "[search]\nmax_results = 5\n";
+        let cfg: Config = toml::from_str(toml).unwrap();
+        assert_eq!(cfg.search.max_results, 5);
+        assert_eq!(cfg.window.width, 600.0);
+        assert_eq!(cfg.appearance.search_font_size, 18.0);
+        assert!(cfg.plugins.apps);
+    }
+
+    #[test]
+    fn parse_full_toml_roundtrip() {
+        let toml = r#"
+[window]
+width = 800.0
+height = 500.0
+decorations = true
+transparent = false
+resizable = true
+
+[appearance]
+background_rgba = [10.0, 10.0, 20.0, 0.8]
+border_rgba = [100.0, 200.0, 255.0, 1.0]
+border_width = 2.0
+border_radius = 12.0
+search_font_size = 20.0
+title_size = 16.0
+desc_size = 13.0
+row_radius = 6.0
+placeholder = "Type here..."
+
+[search]
+max_results = 12
+
+[plugins]
+calc = false
+cmd = true
+files = false
+apps = true
+"#;
+        let cfg: Config = toml::from_str(toml).unwrap();
+        assert_eq!(cfg.window.width, 800.0);
+        assert_eq!(cfg.window.height, 500.0);
+        assert!(cfg.window.decorations);
+        assert!(!cfg.window.transparent);
+        assert_eq!(cfg.appearance.background_rgba, [10.0, 10.0, 20.0, 0.8]);
+        assert_eq!(cfg.appearance.search_font_size, 20.0);
+        assert_eq!(cfg.appearance.placeholder, "Type here...");
+        assert_eq!(cfg.search.max_results, 12);
+        assert!(!cfg.plugins.calc);
+        assert!(!cfg.plugins.files);
+    }
+}

crates/k-launcher-kernel/Cargo.toml

@@ -8,3 +8,4 @@ async-trait = { workspace = true }
 futures = { workspace = true }
 serde = { workspace = true }
 tokio = { workspace = true }
+tracing = { workspace = true }

crates/k-launcher-kernel/src/lib.rs

@@ -3,8 +3,6 @@ use std::sync::Arc;
 use async_trait::async_trait;
 use futures::future::join_all;
 
-pub type PluginName = &'static str;
-
 // --- Newtypes ---
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash, serde::Serialize, serde::Deserialize)]
@@ -31,7 +29,9 @@ impl ResultTitle {
     }
 }
 
-#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, serde::Serialize, serde::Deserialize)]
+#[derive(
+    Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, serde::Serialize, serde::Deserialize,
+)]
 pub struct Score(u32);
 
 impl Score {
@@ -43,6 +43,21 @@ impl Score {
     }
 }
 
+// --- LaunchAction (port) ---
+
+pub enum LaunchAction {
+    SpawnProcess(String),
+    SpawnInTerminal(String),
+    OpenPath(String),
+    CopyToClipboard(String),
+}
+
+// --- AppLauncher port trait ---
+
+pub trait AppLauncher: Send + Sync {
+    fn execute(&self, action: &LaunchAction);
+}
+
 // --- SearchResult ---
 
 pub struct SearchResult {
@@ -51,7 +66,7 @@ pub struct SearchResult {
     pub description: Option<String>,
     pub icon: Option<String>,
     pub score: Score,
-    pub on_execute: Arc<dyn Fn() + Send + Sync>,
+    pub action: LaunchAction,
 }
 
 impl std::fmt::Debug for SearchResult {
@@ -69,30 +84,88 @@ impl std::fmt::Debug for SearchResult {
 
 #[async_trait]
 pub trait Plugin: Send + Sync {
-    fn name(&self) -> PluginName;
+    fn name(&self) -> &str;
     async fn search(&self, query: &str) -> Vec<SearchResult>;
+    fn on_selected(&self, _id: &ResultId) {}
+}
+
+// --- SearchEngine port trait ---
+
+#[async_trait]
+pub trait SearchEngine: Send + Sync {
+    async fn search(&self, query: &str) -> Vec<SearchResult>;
+    fn on_selected(&self, id: &ResultId);
+}
+
+// --- NullSearchEngine ---
+
+pub struct NullSearchEngine;
+
+#[async_trait]
+impl SearchEngine for NullSearchEngine {
+    async fn search(&self, _query: &str) -> Vec<SearchResult> {
+        vec![]
+    }
+    fn on_selected(&self, _id: &ResultId) {}
 }
 
 // --- Kernel (Application use case) ---
 
 pub struct Kernel {
     plugins: Vec<Arc<dyn Plugin>>,
+    max_results: usize,
 }
 
 impl Kernel {
-    pub fn new(plugins: Vec<Arc<dyn Plugin>>) -> Self {
+    pub fn new(plugins: Vec<Arc<dyn Plugin>>, max_results: usize) -> Self {
-        Self { plugins }
+        Self {
+            plugins,
+            max_results,
+        }
+    }
+
+    pub fn on_selected(&self, id: &ResultId) {
+        for plugin in &self.plugins {
+            plugin.on_selected(id);
+        }
     }
 
     pub async fn search(&self, query: &str) -> Vec<SearchResult> {
-        let futures = self.plugins.iter().map(|p| p.search(query));
+        use futures::FutureExt;
-        let nested: Vec<Vec<SearchResult>> = join_all(futures).await;
+        use std::panic::AssertUnwindSafe;
-        let mut flat: Vec<SearchResult> = nested.into_iter().flatten().collect();
+
+        let futures = self
+            .plugins
+            .iter()
+            .map(|p| AssertUnwindSafe(p.search(query)).catch_unwind());
+        let outcomes = join_all(futures).await;
+        let mut flat: Vec<SearchResult> = outcomes
+            .into_iter()
+            .zip(self.plugins.iter())
+            .flat_map(|(outcome, plugin)| match outcome {
+                Ok(results) => results,
+                Err(_) => {
+                    tracing::error!(plugin = plugin.name(), "plugin panicked during search");
+                    vec![]
+                }
+            })
+            .collect();
         flat.sort_by(|a, b| b.score.cmp(&a.score));
+        flat.truncate(self.max_results);
         flat
     }
 }
 
+#[async_trait]
+impl SearchEngine for Kernel {
+    async fn search(&self, query: &str) -> Vec<SearchResult> {
+        self.search(query).await
+    }
+    fn on_selected(&self, id: &ResultId) {
+        self.on_selected(id);
+    }
+}
+
 // --- Tests ---
 
 #[cfg(test)]
@@ -111,7 +184,7 @@ mod tests {
 
     #[async_trait]
     impl Plugin for MockPlugin {
-        fn name(&self) -> PluginName {
+        fn name(&self) -> &str {
             "mock"
         }
 
@@ -125,7 +198,7 @@ mod tests {
                     description: None,
                     icon: None,
                     score: Score::new(*score),
-                    on_execute: Arc::new(|| {}),
+                    action: LaunchAction::SpawnProcess("mock".to_string()),
                 })
                 .collect()
         }
@@ -148,7 +221,7 @@ mod tests {
 
     #[tokio::test]
     async fn empty_kernel_returns_empty() {
-        let k = Kernel::new(vec![]);
+        let k = Kernel::new(vec![], 8);
         assert!(k.search("x").await.is_empty());
     }
 
@@ -159,10 +232,49 @@ mod tests {
             ("higher", 10),
             ("middle", 7),
         ]));
-        let k = Kernel::new(vec![plugin]);
+        let k = Kernel::new(vec![plugin], 8);
         let results = k.search("q").await;
         assert_eq!(results[0].score.value(), 10);
         assert_eq!(results[1].score.value(), 7);
         assert_eq!(results[2].score.value(), 5);
     }
+
+    struct PanicPlugin;
+
+    #[async_trait]
+    impl Plugin for PanicPlugin {
+        fn name(&self) -> &str {
+            "panic-plugin"
+        }
+
+        async fn search(&self, _query: &str) -> Vec<SearchResult> {
+            panic!("test panic");
+        }
+    }
+
+    #[tokio::test]
+    async fn kernel_continues_after_plugin_panic() {
+        let panic_plugin = Arc::new(PanicPlugin);
+        let normal_plugin = Arc::new(MockPlugin::returns(vec![("survivor", 5)]));
+        let k = Kernel::new(vec![panic_plugin, normal_plugin], 8);
+        let results = k.search("q").await;
+        assert_eq!(results.len(), 1);
+        assert_eq!(results[0].title.as_str(), "survivor");
+    }
+
+    #[tokio::test]
+    async fn kernel_truncates_at_max_results() {
+        let plugin = Arc::new(MockPlugin::returns(vec![
+            ("a", 10),
+            ("b", 9),
+            ("c", 8),
+            ("d", 7),
+            ("e", 6),
+        ]));
+        let k = Kernel::new(vec![plugin], 3);
+        let results = k.search("q").await;
+        assert_eq!(results.len(), 3);
+        assert_eq!(results[0].score.value(), 10);
+        assert_eq!(results[2].score.value(), 8);
+    }
 }

crates/k-launcher-os-bridge/Cargo.toml

@@ -4,3 +4,5 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
+k-launcher-kernel = { path = "../k-launcher-kernel" }
+libc = "0.2"

crates/k-launcher-os-bridge/src/lib.rs

@@ -1,20 +1,2 @@
-/// Configuration for the launcher window.
+mod unix_launcher;
-pub struct WindowConfig {
+pub use unix_launcher::UnixAppLauncher;
-    pub width: f32,
-    pub height: f32,
-    pub decorations: bool,
-    pub transparent: bool,
-    pub resizable: bool,
-}
-
-impl WindowConfig {
-    pub fn launcher() -> Self {
-        Self {
-            width: 600.0,
-            height: 400.0,
-            decorations: false,
-            transparent: true,
-            resizable: false,
-        }
-    }
-}

crates/k-launcher-os-bridge/src/unix_launcher.rs

@@ -0,0 +1,190 @@
+use std::os::unix::process::CommandExt;
+use std::process::{Command, Stdio};
+
+use k_launcher_kernel::{AppLauncher, LaunchAction};
+
+fn shell_split(cmd: &str) -> Vec<String> {
+    let mut tokens = Vec::new();
+    let mut current = String::new();
+    let mut in_quotes = false;
+
+    for ch in cmd.chars() {
+        match ch {
+            '"' => in_quotes = !in_quotes,
+            ' ' | '\t' if !in_quotes => {
+                if !current.is_empty() {
+                    tokens.push(current.clone());
+                    current.clear();
+                }
+            }
+            _ => current.push(ch),
+        }
+    }
+    if !current.is_empty() {
+        tokens.push(current);
+    }
+    tokens
+}
+
+fn parse_term_cmd(s: &str) -> (String, Vec<String>) {
+    let mut parts = s.split_whitespace();
+    let bin = parts.next().unwrap_or("").to_string();
+    let args = parts.map(str::to_string).collect();
+    (bin, args)
+}
+
+fn which(bin: &str) -> bool {
+    Command::new("which")
+        .arg(bin)
+        .stdout(Stdio::null())
+        .stderr(Stdio::null())
+        .status()
+        .map(|s| s.success())
+        .unwrap_or(false)
+}
+
+fn resolve_terminal() -> Option<(String, Vec<String>)> {
+    if let Ok(val) = std::env::var("TERM_CMD") {
+        let val = val.trim().to_string();
+        if !val.is_empty() {
+            let (bin, args) = parse_term_cmd(&val);
+            if !bin.is_empty() {
+                return Some((bin, args));
+            }
+        }
+    }
+    if let Ok(val) = std::env::var("TERMINAL") {
+        let bin = val.trim().to_string();
+        if !bin.is_empty() {
+            return Some((bin, vec!["-e".to_string()]));
+        }
+    }
+    for (bin, flag) in &[
+        ("foot", "-e"),
+        ("kitty", "-e"),
+        ("alacritty", "-e"),
+        ("wezterm", "start"),
+        ("konsole", "-e"),
+        ("xterm", "-e"),
+    ] {
+        if which(bin) {
+            return Some((bin.to_string(), vec![flag.to_string()]));
+        }
+    }
+    None
+}
+
+pub struct UnixAppLauncher;
+
+impl UnixAppLauncher {
+    pub fn new() -> Self {
+        Self
+    }
+}
+
+impl Default for UnixAppLauncher {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl AppLauncher for UnixAppLauncher {
+    fn execute(&self, action: &LaunchAction) {
+        match action {
+            LaunchAction::SpawnProcess(cmd) => {
+                let parts = shell_split(cmd);
+                if let Some((bin, args)) = parts.split_first() {
+                    let _ = unsafe {
+                        Command::new(bin)
+                            .args(args)
+                            .stdin(Stdio::null())
+                            .stdout(Stdio::null())
+                            .stderr(Stdio::null())
+                            .pre_exec(|| {
+                                libc::setsid();
+                                Ok(())
+                            })
+                            .spawn()
+                    };
+                }
+            }
+            LaunchAction::SpawnInTerminal(cmd) => {
+                let Some((term_bin, term_args)) = resolve_terminal() else {
+                    return;
+                };
+                let _ = unsafe {
+                    Command::new(&term_bin)
+                        .args(&term_args)
+                        .arg("sh")
+                        .arg("-c")
+                        .arg(cmd)
+                        .stdin(Stdio::null())
+                        .stdout(Stdio::null())
+                        .stderr(Stdio::null())
+                        .pre_exec(|| {
+                            libc::setsid();
+                            Ok(())
+                        })
+                        .spawn()
+                };
+            }
+            LaunchAction::OpenPath(path) => {
+                let _ = Command::new("xdg-open").arg(path).spawn();
+            }
+            LaunchAction::CopyToClipboard(val) => {
+                if Command::new("wl-copy").arg(val).spawn().is_err() {
+                    use std::io::Write;
+                    if let Ok(mut child) = Command::new("xclip")
+                        .args(["-selection", "clipboard"])
+                        .stdin(Stdio::piped())
+                        .spawn()
+                        && let Some(stdin) = child.stdin.as_mut()
+                    {
+                        let _ = stdin.write_all(val.as_bytes());
+                    }
+                }
+            }
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::shell_split;
+
+    #[test]
+    fn split_simple() {
+        assert_eq!(shell_split("firefox"), vec!["firefox"]);
+    }
+
+    #[test]
+    fn split_with_args() {
+        assert_eq!(
+            shell_split("firefox --new-window"),
+            vec!["firefox", "--new-window"]
+        );
+    }
+
+    #[test]
+    fn split_quoted_path() {
+        assert_eq!(shell_split(r#""My App" --flag"#), vec!["My App", "--flag"]);
+    }
+
+    #[test]
+    fn split_quoted_with_spaces() {
+        assert_eq!(
+            shell_split(r#"env "FOO BAR" baz"#),
+            vec!["env", "FOO BAR", "baz"]
+        );
+    }
+
+    #[test]
+    fn split_empty() {
+        assert!(shell_split("").is_empty());
+    }
+
+    #[test]
+    fn split_extra_whitespace() {
+        assert_eq!(shell_split("  a   b  "), vec!["a", "b"]);
+    }
+}

crates/k-launcher-plugin-host/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "k-launcher-plugin-host"
+version = "0.1.0"
+edition = "2024"
+
+[lib]
+name = "k_launcher_plugin_host"
+path = "src/lib.rs"
+
+[dependencies]
+async-trait = { workspace = true }
+k-launcher-kernel = { path = "../k-launcher-kernel" }
+serde = { workspace = true }
+serde_json = { workspace = true }
+tokio = { workspace = true, features = ["process", "io-util", "sync", "time"] }
+tracing = { workspace = true }

crates/k-launcher-plugin-host/src/lib.rs

@@ -0,0 +1,218 @@
+use async_trait::async_trait;
+use k_launcher_kernel::{LaunchAction, Plugin, ResultId, ResultTitle, Score, SearchResult};
+use serde::{Deserialize, Serialize};
+use tokio::io::{AsyncBufReadExt, AsyncWriteExt, BufReader, BufWriter};
+use tokio::process::{ChildStdin, ChildStdout, Command};
+use tokio::sync::Mutex;
+
+// --- Protocol types ---
+
+#[derive(Serialize)]
+struct Query {
+    query: String,
+}
+
+#[derive(Deserialize)]
+struct ExternalResult {
+    id: String,
+    title: String,
+    score: u32,
+    #[serde(default)]
+    description: Option<String>,
+    #[serde(default)]
+    icon: Option<String>,
+    action: ExternalAction,
+}
+
+#[derive(Deserialize)]
+#[serde(tag = "type")]
+enum ExternalAction {
+    SpawnProcess { cmd: String },
+    CopyToClipboard { text: String },
+    OpenPath { path: String },
+}
+
+// --- Process I/O handle ---
+
+struct ProcessIo {
+    stdin: BufWriter<ChildStdin>,
+    stdout: BufReader<ChildStdout>,
+}
+
+async fn do_search(
+    io: &mut ProcessIo,
+    query: &str,
+) -> Result<Vec<ExternalResult>, Box<dyn std::error::Error + Send + Sync>> {
+    let line = serde_json::to_string(&Query {
+        query: query.to_string(),
+    })?;
+    io.stdin.write_all(line.as_bytes()).await?;
+    io.stdin.write_all(b"\n").await?;
+    io.stdin.flush().await?;
+    let mut response = String::new();
+    io.stdout.read_line(&mut response).await?;
+    Ok(serde_json::from_str(&response)?)
+}
+
+// --- ExternalPlugin ---
+
+pub struct ExternalPlugin {
+    name: String,
+    path: String,
+    args: Vec<String>,
+    inner: Mutex<Option<ProcessIo>>,
+}
+
+impl ExternalPlugin {
+    pub fn new(name: impl Into<String>, path: impl Into<String>, args: Vec<String>) -> Self {
+        Self {
+            name: name.into(),
+            path: path.into(),
+            args,
+            inner: Mutex::new(None),
+        }
+    }
+
+    async fn spawn(&self) -> std::io::Result<ProcessIo> {
+        let mut child = Command::new(&self.path)
+            .args(&self.args)
+            .stdin(std::process::Stdio::piped())
+            .stdout(std::process::Stdio::piped())
+            .spawn()?;
+        let stdin = BufWriter::new(child.stdin.take().unwrap());
+        let stdout = BufReader::new(child.stdout.take().unwrap());
+        Ok(ProcessIo { stdin, stdout })
+    }
+}
+
+#[async_trait]
+impl Plugin for ExternalPlugin {
+    fn name(&self) -> &str {
+        &self.name
+    }
+
+    async fn search(&self, query: &str) -> Vec<SearchResult> {
+        let mut guard = self.inner.lock().await;
+
+        if guard.is_none() {
+            match self.spawn().await {
+                Ok(io) => *guard = Some(io),
+                Err(e) => {
+                    tracing::warn!("failed to spawn plugin {}: {e}", self.name);
+                    return vec![];
+                }
+            }
+        }
+
+        let result = match guard.as_mut() {
+            Some(io) => {
+                tokio::time::timeout(std::time::Duration::from_secs(5), do_search(io, query))
+                    .await
+                    .unwrap_or_else(|_| {
+                        tracing::warn!("plugin {} search timed out", self.name);
+                        Err("timeout".into())
+                    })
+            }
+            None => unreachable!(),
+        };
+
+        match result {
+            Ok(results) => results
+                .into_iter()
+                .map(|r| SearchResult {
+                    id: ResultId::new(r.id),
+                    title: ResultTitle::new(r.title),
+                    description: r.description,
+                    icon: r.icon,
+                    score: Score::new(r.score),
+                    action: match r.action {
+                        ExternalAction::SpawnProcess { cmd } => LaunchAction::SpawnProcess(cmd),
+                        ExternalAction::CopyToClipboard { text } => {
+                            LaunchAction::CopyToClipboard(text)
+                        }
+                        ExternalAction::OpenPath { path } => LaunchAction::OpenPath(path),
+                    },
+                })
+                .collect(),
+            Err(e) => {
+                tracing::warn!("plugin {} error: {e}", self.name);
+                *guard = None;
+                vec![]
+            }
+        }
+    }
+}
+
+// --- Tests ---
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn query_serializes_correctly() {
+        let q = Query {
+            query: "firefox".to_string(),
+        };
+        assert_eq!(serde_json::to_string(&q).unwrap(), r#"{"query":"firefox"}"#);
+    }
+
+    #[test]
+    fn result_parses_spawn_action() {
+        let json = r#"[{"id":"1","title":"Firefox","score":80,"action":{"type":"SpawnProcess","cmd":"firefox"}}]"#;
+        let results: Vec<ExternalResult> = serde_json::from_str(json).unwrap();
+        assert_eq!(results.len(), 1);
+        assert_eq!(results[0].id, "1");
+        assert_eq!(results[0].title, "Firefox");
+        assert_eq!(results[0].score, 80);
+        assert!(
+            matches!(&results[0].action, ExternalAction::SpawnProcess { cmd } if cmd == "firefox")
+        );
+    }
+
+    #[test]
+    fn result_parses_copy_action() {
+        let json = r#"[{"id":"c","title":"= 4","score":90,"action":{"type":"CopyToClipboard","text":"4"}}]"#;
+        let results: Vec<ExternalResult> = serde_json::from_str(json).unwrap();
+        assert!(
+            matches!(&results[0].action, ExternalAction::CopyToClipboard { text } if text == "4")
+        );
+    }
+
+    #[test]
+    fn result_parses_open_path_action() {
+        let json = r#"[{"id":"f","title":"/home/user","score":50,"action":{"type":"OpenPath","path":"/home/user"}}]"#;
+        let results: Vec<ExternalResult> = serde_json::from_str(json).unwrap();
+        assert!(
+            matches!(&results[0].action, ExternalAction::OpenPath { path } if path == "/home/user")
+        );
+    }
+
+    #[test]
+    fn result_parses_optional_fields() {
+        let json = r#"[{"id":"x","title":"X","score":10,"description":"desc","icon":"/icon.png","action":{"type":"SpawnProcess","cmd":"x"}}]"#;
+        let results: Vec<ExternalResult> = serde_json::from_str(json).unwrap();
+        assert_eq!(results[0].description.as_deref(), Some("desc"));
+        assert_eq!(results[0].icon.as_deref(), Some("/icon.png"));
+    }
+
+    #[test]
+    fn result_parses_missing_optional_fields() {
+        let json =
+            r#"[{"id":"x","title":"X","score":10,"action":{"type":"SpawnProcess","cmd":"x"}}]"#;
+        let results: Vec<ExternalResult> = serde_json::from_str(json).unwrap();
+        assert!(results[0].description.is_none());
+        assert!(results[0].icon.is_none());
+    }
+
+    #[test]
+    fn invalid_json_is_err() {
+        assert!(serde_json::from_str::<Vec<ExternalResult>>("not json").is_err());
+    }
+
+    // Unused import suppression for Arc (used only in production code path)
+    fn _assert_send_sync() {
+        fn check<T: Send + Sync>() {}
+        check::<ExternalPlugin>();
+    }
+}

crates/k-launcher-ui-egui/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "k-launcher-ui-egui"
+version = "0.1.0"
+edition = "2024"
+
+[lib]
+name = "k_launcher_ui_egui"
+path = "src/lib.rs"
+
+[dependencies]
+eframe = { version = "0.31", default-features = false, features = ["default_fonts", "wayland", "x11", "glow"] }
+egui = "0.31"
+k-launcher-config = { path = "../k-launcher-config" }
+k-launcher-kernel = { path = "../k-launcher-kernel" }
+tokio = { workspace = true }

crates/k-launcher-ui-egui/src/app.rs

@@ -0,0 +1,186 @@
+use std::sync::{Arc, mpsc};
+
+use egui::{Color32, Key, ViewportCommand};
+use k_launcher_kernel::{AppLauncher, SearchEngine, SearchResult};
+
+const BG: Color32 = Color32::from_rgba_premultiplied(20, 20, 30, 230);
+const BORDER_COLOR: Color32 = Color32::from_rgb(229, 125, 33);
+const SELECTED_BG: Color32 = Color32::from_rgba_premultiplied(0, 100, 140, 180);
+const DIM_TEXT: Color32 = Color32::from_rgb(180, 185, 200);
+
+pub struct KLauncherApp {
+    engine: Arc<dyn SearchEngine>,
+    launcher: Arc<dyn AppLauncher>,
+    query: String,
+    results: Vec<SearchResult>,
+    selected: usize,
+    rt: tokio::runtime::Handle,
+    result_tx: mpsc::SyncSender<Vec<SearchResult>>,
+    result_rx: mpsc::Receiver<Vec<SearchResult>>,
+}
+
+impl KLauncherApp {
+    fn new(
+        engine: Arc<dyn SearchEngine>,
+        launcher: Arc<dyn AppLauncher>,
+        rt: tokio::runtime::Handle,
+    ) -> Self {
+        let (result_tx, result_rx) = mpsc::sync_channel(4);
+        Self {
+            engine,
+            launcher,
+            query: String::new(),
+            results: vec![],
+            selected: 0,
+            rt,
+            result_tx,
+            result_rx,
+        }
+    }
+
+    fn trigger_search(&self, query: String) {
+        let engine = self.engine.clone();
+        let tx = self.result_tx.clone();
+        self.rt.spawn(async move {
+            let results = engine.search(&query).await;
+            let _ = tx.send(results);
+        });
+    }
+}
+
+impl eframe::App for KLauncherApp {
+    fn update(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
+        if let Ok(results) = self.result_rx.try_recv() {
+            self.results = results;
+        }
+
+        let mut close = false;
+        let mut launch_selected = false;
+
+        ctx.input(|i| {
+            if i.key_pressed(Key::Escape) {
+                close = true;
+            }
+            if i.key_pressed(Key::Enter) {
+                launch_selected = true;
+            }
+            if i.key_pressed(Key::ArrowDown) {
+                let len = self.results.len();
+                if len > 0 {
+                    self.selected = (self.selected + 1).min(len - 1);
+                }
+            }
+            if i.key_pressed(Key::ArrowUp) && self.selected > 0 {
+                self.selected -= 1;
+            }
+        });
+
+        if close {
+            ctx.send_viewport_cmd(ViewportCommand::Close);
+            return;
+        }
+
+        if launch_selected {
+            if let Some(result) = self.results.get(self.selected) {
+                self.engine.on_selected(&result.id);
+                self.launcher.execute(&result.action);
+            }
+            ctx.send_viewport_cmd(ViewportCommand::Close);
+            return;
+        }
+
+        let frame = egui::Frame::new()
+            .fill(BG)
+            .stroke(egui::Stroke::new(1.0, BORDER_COLOR))
+            .inner_margin(egui::Margin::same(12))
+            .corner_radius(egui::CornerRadius::same(8));
+
+        egui::CentralPanel::default().frame(frame).show(ctx, |ui| {
+            let response = ui.add_sized(
+                [ui.available_width(), 36.0],
+                egui::TextEdit::singleline(&mut self.query)
+                    .hint_text("Search...")
+                    .font(egui::TextStyle::Heading),
+            );
+
+            if response.changed() {
+                self.selected = 0;
+                self.trigger_search(self.query.clone());
+            }
+
+            response.request_focus();
+
+            ui.add_space(8.0);
+
+            if self.results.is_empty() && !self.query.is_empty() {
+                ui.add_space(20.0);
+                ui.with_layout(egui::Layout::top_down(egui::Align::Center), |ui| {
+                    ui.colored_label(DIM_TEXT, "No results");
+                });
+                return;
+            }
+
+            egui::ScrollArea::vertical().show(ui, |ui| {
+                ui.set_width(ui.available_width());
+                for (i, result) in self.results.iter().enumerate() {
+                    let is_selected = i == self.selected;
+                    let bg = if is_selected {
+                        SELECTED_BG
+                    } else {
+                        Color32::TRANSPARENT
+                    };
+
+                    let row_frame = egui::Frame::new()
+                        .fill(bg)
+                        .inner_margin(egui::Margin {
+                            left: 8,
+                            right: 8,
+                            top: 6,
+                            bottom: 6,
+                        })
+                        .corner_radius(egui::CornerRadius::same(4));
+
+                    row_frame.show(ui, |ui| {
+                        ui.set_width(ui.available_width());
+                        ui.horizontal(|ui| {
+                            ui.add_space(8.0);
+                            ui.vertical(|ui| {
+                                ui.label(result.title.as_str());
+                                if let Some(desc) = &result.description {
+                                    ui.colored_label(DIM_TEXT, desc);
+                                }
+                            });
+                        });
+                    });
+
+                    ui.add_space(2.0);
+                }
+            });
+        });
+    }
+}
+
+pub fn run(
+    engine: Arc<dyn SearchEngine>,
+    launcher: Arc<dyn AppLauncher>,
+    window_cfg: &k_launcher_config::WindowCfg,
+) -> Result<(), eframe::Error> {
+    let rt = tokio::runtime::Runtime::new().expect("tokio runtime");
+    let handle = rt.handle().clone();
+
+    let options = eframe::NativeOptions {
+        viewport: egui::ViewportBuilder::default()
+            .with_inner_size([window_cfg.width, window_cfg.height])
+            .with_decorations(window_cfg.decorations)
+            .with_transparent(window_cfg.transparent)
+            .with_resizable(window_cfg.resizable)
+            .with_always_on_top(),
+        ..Default::default()
+    };
+
+    eframe::run_native(
+        "K-Launcher",
+        options,
+        Box::new(move |_cc| Ok(Box::new(KLauncherApp::new(engine, launcher, handle)))),
+    )
+}

crates/k-launcher-ui-egui/src/lib.rs

@@ -0,0 +1,13 @@
+mod app;
+
+use std::sync::Arc;
+
+use k_launcher_kernel::{AppLauncher, SearchEngine};
+
+pub fn run(
+    engine: Arc<dyn SearchEngine>,
+    launcher: Arc<dyn AppLauncher>,
+    window_cfg: &k_launcher_config::WindowCfg,
+) -> Result<(), eframe::Error> {
+    app::run(engine, launcher, window_cfg)
+}

crates/k-launcher-ui/Cargo.toml

@@ -9,5 +9,7 @@ path = "src/lib.rs"
 
 [dependencies]
 iced = { workspace = true }
+k-launcher-config = { path = "../k-launcher-config" }
 k-launcher-kernel = { path = "../k-launcher-kernel" }
+k-launcher-os-bridge = { path = "../k-launcher-os-bridge" }
 tokio = { workspace = true }

crates/k-launcher-ui/src/app.rs

@@ -1,34 +1,57 @@
 use std::sync::Arc;
 
 use iced::{
-    Color, Element, Length, Size, Subscription, Task,
+    Border, Color, Element, Length, Size, Subscription, Task, event,
-    event,
     keyboard::{Event as KeyEvent, Key, key::Named},
-    widget::{column, container, image, row, scrollable, svg, text, text_input, Space},
+    widget::{Space, column, container, image, row, scrollable, svg, text, text_input},
     window,
 };
 
-use k_launcher_kernel::{Kernel, SearchResult};
+use k_launcher_config::AppearanceCfg;
-
+use k_launcher_kernel::{AppLauncher, NullSearchEngine, SearchEngine, SearchResult};
-use crate::theme;
 
 static INPUT_ID: std::sync::LazyLock<iced::widget::Id> =
     std::sync::LazyLock::new(|| iced::widget::Id::new("search"));
 
+#[derive(Clone)]
+pub(crate) struct EngineHandle(Arc<dyn SearchEngine>);
+
+impl std::fmt::Debug for EngineHandle {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.write_str("EngineHandle")
+    }
+}
+
+fn rgba(c: &[f32; 4]) -> Color {
+    Color::from_rgba8(c[0] as u8, c[1] as u8, c[2] as u8, c[3])
+}
+
 pub struct KLauncherApp {
-    kernel: Arc<Kernel>,
+    engine: Arc<dyn SearchEngine>,
+    launcher: Arc<dyn AppLauncher>,
     query: String,
     results: Arc<Vec<SearchResult>>,
     selected: usize,
+    cfg: AppearanceCfg,
+    error: Option<String>,
+    search_epoch: u64,
 }
 
 impl KLauncherApp {
-    fn new(kernel: Arc<Kernel>) -> Self {
+    fn new(
+        engine: Arc<dyn SearchEngine>,
+        launcher: Arc<dyn AppLauncher>,
+        cfg: AppearanceCfg,
+    ) -> Self {
         Self {
-            kernel,
+            engine,
+            launcher,
             query: String::new(),
             results: Arc::new(vec![]),
             selected: 0,
+            cfg,
+            error: None,
+            search_epoch: 0,
         }
     }
 }
@@ -36,23 +59,45 @@ impl KLauncherApp {
 #[derive(Debug, Clone)]
 pub enum Message {
     QueryChanged(String),
-    ResultsReady(Arc<Vec<SearchResult>>),
+    ResultsReady(u64, Arc<Vec<SearchResult>>),
     KeyPressed(KeyEvent),
+    EngineReady(EngineHandle),
+    EngineInitFailed(String),
 }
 
 fn update(state: &mut KLauncherApp, message: Message) -> Task<Message> {
     match message {
         Message::QueryChanged(q) => {
+            state.error = None;
             state.query = q.clone();
             state.selected = 0;
-            let kernel = state.kernel.clone();
+            state.search_epoch += 1;
+            let epoch = state.search_epoch;
+            let engine = state.engine.clone();
             Task::perform(
-                async move { kernel.search(&q).await },
+                async move {
-                |results| Message::ResultsReady(Arc::new(results)),
+                    tokio::time::sleep(std::time::Duration::from_millis(50)).await;
+                    (epoch, engine.search(&q).await)
+                },
+                |(epoch, results)| Message::ResultsReady(epoch, Arc::new(results)),
             )
         }
-        Message::ResultsReady(results) => {
+        Message::ResultsReady(epoch, results) => {
-            state.results = results;
+            if epoch == state.search_epoch {
+                state.results = results;
+            }
+            Task::none()
+        }
+        Message::EngineInitFailed(msg) => {
+            state.error = Some(msg);
+            Task::none()
+        }
+        Message::EngineReady(handle) => {
+            state.engine = handle.0;
+            if !state.query.is_empty() {
+                let q = state.query.clone();
+                return Task::done(Message::QueryChanged(q));
+            }
             Task::none()
         }
         Message::KeyPressed(event) => {
@@ -65,7 +110,9 @@ fn update(state: &mut KLauncherApp, message: Message) -> Task<Message> {
             };
             let len = state.results.len();
             match named {
-                Named::Escape => std::process::exit(0),
+                Named::Escape => {
+                    std::process::exit(0);
+                }
                 Named::ArrowDown => {
                     if len > 0 {
                         state.selected = (state.selected + 1).min(len - 1);
@@ -78,7 +125,8 @@ fn update(state: &mut KLauncherApp, message: Message) -> Task<Message> {
                 }
                 Named::Enter => {
                     if let Some(result) = state.results.get(state.selected) {
-                        (result.on_execute)();
+                        state.engine.on_selected(&result.id);
+                        state.launcher.execute(&result.action);
                     }
                     std::process::exit(0);
                 }
@@ -90,13 +138,28 @@ fn update(state: &mut KLauncherApp, message: Message) -> Task<Message> {
 }
 
 fn view(state: &KLauncherApp) -> Element<'_, Message> {
-    let colors = &*theme::AERO;
+    let cfg = &state.cfg;
+    let border_color = rgba(&cfg.border_rgba);
 
-    let search_bar = text_input("Search...", &state.query)
+    let search_bar = text_input(&cfg.placeholder, &state.query)
         .id(INPUT_ID.clone())
         .on_input(Message::QueryChanged)
         .padding(12)
-        .size(18);
+        .size(cfg.search_font_size)
+        .style(|theme, _status| {
+            let mut s =
+                iced::widget::text_input::default(theme, iced::widget::text_input::Status::Active);
+            s.border = Border {
+                color: Color::TRANSPARENT,
+                width: 0.0,
+                radius: 0.0.into(),
+            };
+            s
+        });
+
+    let row_radius: f32 = cfg.row_radius;
+    let title_size: f32 = cfg.title_size;
+    let desc_size: f32 = cfg.desc_size;
 
     let result_rows: Vec<Element<'_, Message>> = state
         .results
@@ -105,48 +168,99 @@ fn view(state: &KLauncherApp) -> Element<'_, Message> {
         .map(|(i, result)| {
             let is_selected = i == state.selected;
             let bg_color = if is_selected {
-                colors.border_cyan
+                border_color
             } else {
                 Color::from_rgba8(255, 255, 255, 0.07)
             };
             let icon_el: Element<'_, Message> = match &result.icon {
-                Some(p) if p.ends_with(".svg") =>
+                Some(p) if p.ends_with(".svg") => {
-                    svg(svg::Handle::from_path(p)).width(24).height(24).into(),
+                    svg(svg::Handle::from_path(p)).width(24).height(24).into()
-                Some(p) =>
+                }
-                    image(image::Handle::from_path(p)).width(24).height(24).into(),
+                Some(p) => image(image::Handle::from_path(p))
+                    .width(24)
+                    .height(24)
+                    .into(),
                 None => Space::new().width(24).height(24).into(),
             };
-            container(
+            let title_col: Element<'_, Message> = if let Some(desc) = &result.description {
-                row![icon_el, text(result.title.as_str()).size(15)]
+                column![
-                    .spacing(8)
+                    text(result.title.as_str()).size(title_size),
-                    .align_y(iced::Center),
+                    text(desc)
-            )
+                        .size(desc_size)
+                        .color(Color::from_rgba8(210, 215, 230, 1.0)),
+                ]
+                .into()
+            } else {
+                text(result.title.as_str()).size(title_size).into()
+            };
+            container(row![icon_el, title_col].spacing(8).align_y(iced::Center))
                 .width(Length::Fill)
                 .padding([6, 12])
                 .style(move |_theme| container::Style {
                     background: Some(iced::Background::Color(bg_color)),
+                    border: Border {
+                        color: Color::TRANSPARENT,
+                        width: 0.0,
+                        radius: row_radius.into(),
+                    },
                     ..Default::default()
                 })
                 .into()
         })
         .collect();
 
-    let results_list =
+    let results_list = if state.results.is_empty() && !state.query.is_empty() {
-        scrollable(column(result_rows).spacing(2).width(Length::Fill)).height(Length::Fill);
+        scrollable(
+            container(
+                text("No results")
+                    .size(title_size)
+                    .color(Color::from_rgba8(180, 180, 200, 0.5)),
+            )
+            .width(Length::Fill)
+            .align_x(iced::Center)
+            .padding([20, 0]),
+        )
+        .height(Length::Fill)
+    } else {
+        scrollable(column(result_rows).spacing(2).width(Length::Fill)).height(Length::Fill)
+    };
 
-    let content = column![search_bar, results_list]
+    let maybe_error: Option<Element<'_, Message>> = state.error.as_ref().map(|msg| {
+        container(
+            text(msg.as_str())
+                .size(12.0)
+                .color(Color::from_rgba8(255, 80, 80, 1.0)),
+        )
+        .width(Length::Fill)
+        .padding([4, 12])
+        .into()
+    });
+
+    let mut content_children: Vec<Element<'_, Message>> =
+        vec![search_bar.into(), results_list.into()];
+    if let Some(err) = maybe_error {
+        content_children.push(err);
+    }
+    let content = column(content_children)
         .spacing(8)
         .padding(12)
         .width(Length::Fill)
         .height(Length::Fill);
 
+    let bg_color = rgba(&cfg.background_rgba);
+    let border_width = cfg.border_width;
+    let border_radius = cfg.border_radius;
+
     container(content)
         .width(Length::Fill)
         .height(Length::Fill)
-        .style(|_theme| container::Style {
+        .style(move |_theme| container::Style {
-            background: Some(iced::Background::Color(Color::from_rgba8(
+            background: Some(iced::Background::Color(bg_color)),
-                20, 20, 30, 0.9,
+            border: Border {
-            ))),
+                color: border_color,
+                width: border_width,
+                radius: border_radius.into(),
+            },
             ..Default::default()
         })
         .into()
@@ -159,25 +273,46 @@ fn subscription(_state: &KLauncherApp) -> Subscription<Message> {
     })
 }
 
-pub fn run(kernel: Arc<Kernel>) -> iced::Result {
+pub fn run(
+    engine_factory: Arc<dyn Fn() -> Arc<dyn SearchEngine> + Send + Sync>,
+    launcher: Arc<dyn AppLauncher>,
+    window_cfg: &k_launcher_config::WindowCfg,
+    appearance_cfg: AppearanceCfg,
+) -> iced::Result {
     iced::application(
         move || {
-            let app = KLauncherApp::new(kernel.clone());
+            let app = KLauncherApp::new(
+                Arc::new(NullSearchEngine),
+                launcher.clone(),
+                appearance_cfg.clone(),
+            );
             let focus = iced::widget::operation::focus(INPUT_ID.clone());
-            (app, focus)
+            let ef = engine_factory.clone();
+            let init = Task::perform(
+                async move {
+                    tokio::task::spawn_blocking(move || ef())
+                        .await
+                        .map_err(|e| format!("Engine init failed: {e}"))
+                },
+                |result| match result {
+                    Ok(e) => Message::EngineReady(EngineHandle(e)),
+                    Err(msg) => Message::EngineInitFailed(msg),
+                },
+            );
+            (app, Task::batch([focus, init]))
         },
         update,
         view,
     )
-        .title("K-Launcher")
+    .title("K-Launcher")
-        .subscription(subscription)
+    .subscription(subscription)
-        .window(window::Settings {
+    .window(window::Settings {
-            size: Size::new(600.0, 400.0),
+        size: Size::new(window_cfg.width, window_cfg.height),
-            position: window::Position::Centered,
+        position: window::Position::Centered,
-            decorations: false,
+        decorations: window_cfg.decorations,
-            transparent: true,
+        transparent: window_cfg.transparent,
-            resizable: false,
+        resizable: window_cfg.resizable,
-            ..Default::default()
+        ..Default::default()
-        })
+    })
-        .run()
+    .run()
 }

crates/k-launcher-ui/src/lib.rs

@@ -1,11 +1,15 @@
 mod app;
-pub mod theme;
 
 use std::sync::Arc;
 
-use k_launcher_kernel::Kernel;
+use k_launcher_config::{AppearanceCfg, WindowCfg};
+use k_launcher_kernel::{AppLauncher, SearchEngine};
 
-
+pub fn run(
-pub fn run(kernel: Arc<Kernel>) -> iced::Result {
+    engine_factory: Arc<dyn Fn() -> Arc<dyn SearchEngine> + Send + Sync>,
-    app::run(kernel)
+    launcher: Arc<dyn AppLauncher>,
+    window_cfg: &WindowCfg,
+    appearance_cfg: AppearanceCfg,
+) -> iced::Result {
+    app::run(engine_factory, launcher, window_cfg, appearance_cfg)
 }

crates/k-launcher-ui/src/theme.rs

@@ -1,35 +0,0 @@
-use iced::{
-    Color, Gradient,
-    gradient::{ColorStop, Linear},
-};
-
-pub struct AeroColors {
-    pub glass_bg: Color,
-    pub gloss_highlight: Gradient,
-    pub border_cyan: Color,
-}
-
-pub static AERO: std::sync::LazyLock<AeroColors> =
-    std::sync::LazyLock::new(AeroColors::standard);
-
-impl AeroColors {
-    pub fn standard() -> Self {
-        Self {
-            // Semi-transparent "Aero Glass" base
-            glass_bg: Color::from_rgba8(255, 255, 255, 0.2),
-            // Cyan/Blue glow typical of the 2008 era
-            border_cyan: Color::from_rgb8(0, 183, 235),
-            // We'll use this for the "shine" effect on buttons
-            gloss_highlight: Gradient::Linear(Linear::new(0.0).add_stops([
-                ColorStop {
-                    color: Color::from_rgba8(255, 255, 255, 0.5),
-                    offset: 0.0,
-                },
-                ColorStop {
-                    color: Color::from_rgba8(255, 255, 255, 0.0),
-                    offset: 1.0,
-                },
-            ])),
-        }
-    }
-}

crates/k-launcher/Cargo.toml

@@ -4,14 +4,38 @@ version = "0.1.0"
 edition = "2024"
 default-run = "k-launcher"
 
+[profile.release]
+lto = true
+strip = true
+codegen-units = 1
+opt-level = 3
+
 [[bin]]
 name = "k-launcher"
 path = "src/main.rs"
 
+[[bin]]
+name = "k-launcher-egui"
+path = "src/main_egui.rs"
+required-features = ["egui"]
+
+[features]
+egui = ["dep:k-launcher-ui-egui"]
+
 [dependencies]
 iced = { workspace = true }
+k-launcher-config = { path = "../k-launcher-config" }
 k-launcher-kernel = { path = "../k-launcher-kernel" }
+k-launcher-plugin-host = { path = "../k-launcher-plugin-host" }
+k-launcher-os-bridge = { path = "../k-launcher-os-bridge" }
 k-launcher-ui = { path = "../k-launcher-ui" }
+k-launcher-ui-egui = { path = "../k-launcher-ui-egui", optional = true }
 plugin-apps = { path = "../plugins/plugin-apps" }
 plugin-calc = { path = "../plugins/plugin-calc" }
+plugin-cmd = { path = "../plugins/plugin-cmd" }
+plugin-files = { path = "../plugins/plugin-files" }
+dirs = { workspace = true }
 tokio = { workspace = true }
+tracing = { workspace = true }
+tracing-appender = "0.2"
+tracing-subscriber = { version = "0.3", features = ["env-filter"] }

crates/k-launcher/src/main.rs

@@ -1,13 +1,79 @@
 use std::sync::Arc;
 
 use k_launcher_kernel::Kernel;
-use plugin_apps::{AppsPlugin, FsDesktopEntrySource};
+use k_launcher_os_bridge::UnixAppLauncher;
+use k_launcher_plugin_host::ExternalPlugin;
+#[cfg(target_os = "linux")]
+use plugin_apps::linux::FsDesktopEntrySource;
+use plugin_apps::{AppsPlugin, frecency::FrecencyStore};
 use plugin_calc::CalcPlugin;
+use plugin_cmd::CmdPlugin;
+use plugin_files::FilesPlugin;
 
-fn main() -> iced::Result {
+fn init_logging() -> tracing_appender::non_blocking::WorkerGuard {
-    let kernel = Arc::new(Kernel::new(vec![
+    use tracing_subscriber::{EnvFilter, layer::SubscriberExt, util::SubscriberInitExt};
-        Arc::new(CalcPlugin::new()),
+
-        Arc::new(AppsPlugin::new(FsDesktopEntrySource::new())),
+    let log_dir = dirs::data_local_dir()
-    ]));
+        .map(|d| d.join("k-launcher/logs"))
-    k_launcher_ui::run(kernel)
+        .unwrap_or_else(|| std::path::PathBuf::from("/tmp/k-launcher/logs"));
+    std::fs::create_dir_all(&log_dir).ok();
+
+    let file_appender = tracing_appender::rolling::daily(&log_dir, "k-launcher.log");
+    let (non_blocking, guard) = tracing_appender::non_blocking(file_appender);
+
+    let env_filter = EnvFilter::try_from_default_env().unwrap_or_else(|_| EnvFilter::new("info"));
+
+    tracing_subscriber::registry()
+        .with(env_filter)
+        .with(tracing_subscriber::fmt::layer().with_writer(std::io::stderr))
+        .with(tracing_subscriber::fmt::layer().with_writer(non_blocking))
+        .init();
+
+    guard
+}
+
+fn main() {
+    let _guard = init_logging();
+
+    if let Err(e) = run_ui() {
+        eprintln!("error: UI: {e}");
+        std::process::exit(1);
+    }
+}
+
+fn build_engine(cfg: Arc<k_launcher_config::Config>) -> Arc<dyn k_launcher_kernel::SearchEngine> {
+    let frecency = FrecencyStore::load();
+    let mut plugins: Vec<Arc<dyn k_launcher_kernel::Plugin>> = vec![];
+    if cfg.plugins.cmd {
+        plugins.push(Arc::new(CmdPlugin::new()));
+    }
+    if cfg.plugins.calc {
+        plugins.push(Arc::new(CalcPlugin::new()));
+    }
+    if cfg.plugins.files {
+        plugins.push(Arc::new(FilesPlugin::new()));
+    }
+    if cfg.plugins.apps {
+        plugins.push(Arc::new(AppsPlugin::new(
+            FsDesktopEntrySource::new(),
+            frecency,
+        )));
+    }
+    for ext in &cfg.plugins.external {
+        plugins.push(Arc::new(ExternalPlugin::new(
+            &ext.name,
+            &ext.path,
+            ext.args.clone(),
+        )));
+    }
+    Arc::new(Kernel::new(plugins, cfg.search.max_results))
+}
+
+fn run_ui() -> iced::Result {
+    let cfg = Arc::new(k_launcher_config::load());
+    let launcher = Arc::new(UnixAppLauncher::new());
+    let factory_cfg = cfg.clone();
+    let factory: Arc<dyn Fn() -> Arc<dyn k_launcher_kernel::SearchEngine> + Send + Sync> =
+        Arc::new(move || build_engine(factory_cfg.clone()));
+    k_launcher_ui::run(factory, launcher, &cfg.window, cfg.appearance.clone())
 }

crates/k-launcher/src/main_egui.rs

@@ -0,0 +1,27 @@
+use std::sync::Arc;
+
+use k_launcher_kernel::Kernel;
+use k_launcher_os_bridge::UnixAppLauncher;
+#[cfg(target_os = "linux")]
+use plugin_apps::linux::FsDesktopEntrySource;
+use plugin_apps::{AppsPlugin, frecency::FrecencyStore};
+use plugin_calc::CalcPlugin;
+use plugin_cmd::CmdPlugin;
+use plugin_files::FilesPlugin;
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let cfg = k_launcher_config::load();
+    let launcher = Arc::new(UnixAppLauncher::new());
+    let frecency = FrecencyStore::load();
+    let kernel: Arc<dyn k_launcher_kernel::SearchEngine> = Arc::new(Kernel::new(
+        vec![
+            Arc::new(CmdPlugin::new()),
+            Arc::new(CalcPlugin::new()),
+            Arc::new(FilesPlugin::new()),
+            Arc::new(AppsPlugin::new(FsDesktopEntrySource::new(), frecency)),
+        ],
+        8,
+    ));
+    k_launcher_ui_egui::run(kernel, launcher, &cfg.window)?;
+    Ok(())
+}

crates/plugins/plugin-apps/Cargo.toml

@@ -7,13 +7,17 @@ edition = "2024"
 name = "plugin_apps"
 path = "src/lib.rs"
 
-[[bin]]
-name = "plugin-apps"
-path = "src/main.rs"
-
 [dependencies]
 async-trait = { workspace = true }
+bincode = { workspace = true }
+dirs = { workspace = true }
 k-launcher-kernel = { path = "../../k-launcher-kernel" }
-libc = "0.2"
+nucleo-matcher = "0.3"
+serde = { workspace = true }
+serde_json = "1.0"
 tokio = { workspace = true }
-xdg = "2"
+tracing = { workspace = true }
+
+[target.'cfg(target_os = "linux")'.dependencies]
+linicon = "2.3.0"
+xdg = "3"

crates/plugins/plugin-apps/src/frecency.rs

@@ -0,0 +1,154 @@
+use std::{
+    collections::HashMap,
+    path::PathBuf,
+    sync::{Arc, Mutex},
+    time::{SystemTime, UNIX_EPOCH},
+};
+
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+struct Entry {
+    count: u32,
+    last_used: u64,
+}
+
+pub struct FrecencyStore {
+    path: PathBuf,
+    data: Mutex<HashMap<String, Entry>>,
+}
+
+impl FrecencyStore {
+    pub fn new(path: PathBuf) -> Arc<Self> {
+        let data = std::fs::read_to_string(&path)
+            .ok()
+            .and_then(|s| serde_json::from_str(&s).ok())
+            .unwrap_or_default();
+        Arc::new(Self {
+            path,
+            data: Mutex::new(data),
+        })
+    }
+
+    #[cfg(test)]
+    pub fn new_for_test() -> Arc<Self> {
+        Arc::new(Self {
+            path: PathBuf::from("/dev/null"),
+            data: Mutex::new(HashMap::new()),
+        })
+    }
+
+    pub fn load() -> Arc<Self> {
+        let Some(data_home) = xdg::BaseDirectories::new().get_data_home() else {
+            tracing::warn!("XDG_DATA_HOME unavailable; frecency disabled (in-memory only)");
+            return Arc::new(Self {
+                path: PathBuf::from("/dev/null"),
+                data: Mutex::new(HashMap::new()),
+            });
+        };
+        let path = data_home.join("k-launcher").join("frecency.json");
+        Self::new(path)
+    }
+
+    pub fn record(&self, id: &str) {
+        let now = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .unwrap_or_default()
+            .as_secs();
+        let json = {
+            let mut data = self.data.lock().unwrap();
+            let entry = data.entry(id.to_string()).or_insert(Entry {
+                count: 0,
+                last_used: 0,
+            });
+            entry.count += 1;
+            entry.last_used = now;
+            serde_json::to_string(&*data).ok()
+        }; // lock released here
+        if let Some(json) = json {
+            if let Some(parent) = self.path.parent() {
+                let _ = std::fs::create_dir_all(parent);
+            }
+            let _ = std::fs::write(&self.path, json);
+        }
+    }
+
+    pub fn frecency_score(&self, id: &str) -> u32 {
+        let data = self.data.lock().unwrap();
+        let Some(entry) = data.get(id) else { return 0 };
+        let now = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .unwrap_or_default()
+            .as_secs();
+        let age_secs = now.saturating_sub(entry.last_used);
+        entry.count * decay_factor(age_secs)
+    }
+
+    pub fn top_ids(&self, n: usize) -> Vec<String> {
+        let data = self.data.lock().unwrap();
+        let now = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .unwrap_or_default()
+            .as_secs();
+        let mut scored: Vec<(String, u32)> = data
+            .iter()
+            .map(|(id, entry)| {
+                let age_secs = now.saturating_sub(entry.last_used);
+                (id.clone(), entry.count * decay_factor(age_secs))
+            })
+            .collect();
+        scored.sort_by(|a, b| b.1.cmp(&a.1));
+        scored.into_iter().take(n).map(|(id, _)| id).collect()
+    }
+}
+
+fn decay_factor(age_secs: u64) -> u32 {
+    if age_secs < 3600 {
+        4
+    } else if age_secs < 86400 {
+        2
+    } else {
+        1
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn make_store() -> Arc<FrecencyStore> {
+        Arc::new(FrecencyStore {
+            path: PathBuf::from("/dev/null"),
+            data: Mutex::new(HashMap::new()),
+        })
+    }
+
+    #[test]
+    fn record_increments_count() {
+        let store = make_store();
+        store.record("app-firefox");
+        store.record("app-firefox");
+        let data = store.data.lock().unwrap();
+        assert_eq!(data["app-firefox"].count, 2);
+    }
+
+    #[test]
+    fn record_updates_last_used() {
+        let store = make_store();
+        store.record("app-firefox");
+        let data = store.data.lock().unwrap();
+        assert!(data["app-firefox"].last_used > 0);
+    }
+
+    #[test]
+    fn top_ids_returns_sorted_order() {
+        let store = make_store();
+        store.record("app-firefox");
+        store.record("app-code");
+        store.record("app-code");
+        store.record("app-code");
+        let top = store.top_ids(2);
+        assert_eq!(top[0], "app-code");
+        assert_eq!(top[1], "app-firefox");
+    }
+}

crates/plugins/plugin-apps/src/lib.rs

@@ -1,8 +1,17 @@
-use std::{path::Path, process::{Command, Stdio}, sync::Arc};
+pub mod frecency;
-use std::os::unix::process::CommandExt;
+#[cfg(target_os = "linux")]
+pub mod linux;
+
+use std::{
+    collections::HashMap,
+    path::{Path, PathBuf},
+    sync::{Arc, RwLock},
+};
 
 use async_trait::async_trait;
-use k_launcher_kernel::{Plugin, PluginName, ResultId, ResultTitle, Score, SearchResult};
+use k_launcher_kernel::{LaunchAction, Plugin, ResultId, ResultTitle, Score, SearchResult};
+
+use crate::frecency::FrecencyStore;
 
 // --- Domain newtypes ---
 
@@ -48,6 +57,8 @@ pub struct DesktopEntry {
     pub name: AppName,
     pub exec: ExecCommand,
     pub icon: Option<IconPath>,
+    pub category: Option<String>,
+    pub keywords: Vec<String>,
 }
 
 // --- Swappable source trait (Application layer principle) ---
@@ -59,214 +70,268 @@ pub trait DesktopEntrySource: Send + Sync {
 // --- Cached entry (pre-computed at construction) ---
 
 struct CachedEntry {
+    id: String,
     name: AppName,
-    name_lc: String,
+    keywords_lc: Vec<String>,
+    category: Option<String>,
     icon: Option<String>,
-    on_execute: Arc<dyn Fn() + Send + Sync>,
+    exec: String,
+}
+
+// --- Serializable cache data (no closures) ---
+
+#[derive(serde::Serialize, serde::Deserialize)]
+struct CachedEntryData {
+    id: String,
+    name: String,
+    keywords_lc: Vec<String>,
+    category: Option<String>,
+    icon: Option<String>,
+    exec: String,
+}
+
+fn cache_path() -> Option<PathBuf> {
+    dirs::cache_dir().map(|d| d.join("k-launcher/apps.bin"))
+}
+
+fn load_from_path(path: &Path) -> Option<HashMap<String, CachedEntry>> {
+    let data = std::fs::read(path).ok()?;
+    let (entries_data, _): (Vec<CachedEntryData>, _) =
+        bincode::serde::decode_from_slice(&data, bincode::config::standard()).ok()?;
+    let map = entries_data
+        .into_iter()
+        .map(|e| {
+            let cached = CachedEntry {
+                id: e.id.clone(),
+                name: AppName::new(e.name),
+                keywords_lc: e.keywords_lc,
+                category: e.category,
+                icon: e.icon,
+                exec: e.exec,
+            };
+            (e.id, cached)
+        })
+        .collect();
+    Some(map)
+}
+
+fn save_to_path(path: &Path, entries: &HashMap<String, CachedEntry>) {
+    if let Some(dir) = path.parent() {
+        std::fs::create_dir_all(dir).ok();
+    }
+    let data: Vec<CachedEntryData> = entries
+        .values()
+        .map(|e| CachedEntryData {
+            id: e.id.clone(),
+            name: e.name.as_str().to_string(),
+            keywords_lc: e.keywords_lc.clone(),
+            category: e.category.clone(),
+            icon: e.icon.clone(),
+            exec: e.exec.clone(),
+        })
+        .collect();
+    if let Ok(encoded) = bincode::serde::encode_to_vec(&data, bincode::config::standard()) {
+        std::fs::write(path, encoded).ok();
+    }
+}
+
+fn build_entries(
+    source: &impl DesktopEntrySource,
+    _frecency: &Arc<FrecencyStore>,
+) -> HashMap<String, CachedEntry> {
+    source
+        .entries()
+        .into_iter()
+        .map(|e| {
+            let id = format!("app-{}:{}", e.name.as_str(), e.exec.as_str());
+            let keywords_lc = e.keywords.iter().map(|k| k.to_lowercase()).collect();
+            #[cfg(target_os = "linux")]
+            let icon = e
+                .icon
+                .as_ref()
+                .and_then(|p| linux::resolve_icon_path(p.as_str()));
+            #[cfg(not(target_os = "linux"))]
+            let icon: Option<String> = None;
+            let exec = e.exec.as_str().to_string();
+            let cached = CachedEntry {
+                id: id.clone(),
+                keywords_lc,
+                category: e.category,
+                icon,
+                exec,
+                name: e.name,
+            };
+            (id, cached)
+        })
+        .collect()
 }
 
 // --- Plugin ---
 
 pub struct AppsPlugin {
-    entries: Vec<CachedEntry>,
+    entries: Arc<RwLock<HashMap<String, CachedEntry>>>,
+    frecency: Arc<FrecencyStore>,
 }
 
 impl AppsPlugin {
-    pub fn new(source: impl DesktopEntrySource) -> Self {
+    pub fn new(source: impl DesktopEntrySource + 'static, frecency: Arc<FrecencyStore>) -> Self {
-        let entries = source
+        Self::new_impl(source, frecency, cache_path())
-            .entries()
+    }
-            .into_iter()
+
-            .map(|e| {
+    fn new_impl(
-                let name_lc = e.name.as_str().to_lowercase();
+        source: impl DesktopEntrySource + 'static,
-                let icon = e.icon.as_ref().and_then(|p| resolve_icon_path(p.as_str()));
+        frecency: Arc<FrecencyStore>,
-                let exec = e.exec.clone();
+        cp: Option<PathBuf>,
-                CachedEntry {
+    ) -> Self {
-                    name_lc,
+        let cached = cp.as_deref().and_then(load_from_path);
-                    icon,
+
-                    on_execute: Arc::new(move || {
+        let entries = if let Some(from_cache) = cached {
-                        let parts: Vec<&str> = exec.as_str().split_whitespace().collect();
+            // Serve cache immediately; refresh in background.
-                        if let Some((cmd, args)) = parts.split_first() {
+            let map = Arc::new(RwLock::new(from_cache));
-                            let _ = unsafe {
+            let entries_bg = Arc::clone(&map);
-                                Command::new(cmd)
+            let frecency_bg = Arc::clone(&frecency);
-                                    .args(args)
+            let cp_bg = cp.clone();
-                                    .stdin(Stdio::null())
+            std::thread::spawn(move || {
-                                    .stdout(Stdio::null())
+                let fresh = build_entries(&source, &frecency_bg);
-                                    .stderr(Stdio::null())
+                if let Some(path) = cp_bg {
-                                    .pre_exec(|| {
+                    save_to_path(&path, &fresh);
-                                        libc::setsid();
-                                        Ok(())
-                                    })
-                                    .spawn()
-                            };
-                        }
-                    }),
-                    name: e.name,
                 }
-            })
+                *entries_bg.write().unwrap() = fresh;
-            .collect();
+            });
-        Self { entries }
+            map
+        } else {
+            // No cache: build synchronously, then persist.
+            let initial = build_entries(&source, &frecency);
+            if let Some(path) = &cp {
+                save_to_path(path, &initial);
+            }
+            Arc::new(RwLock::new(initial))
+        };
+
+        Self { entries, frecency }
+    }
+
+    #[cfg(test)]
+    fn new_for_test(
+        source: impl DesktopEntrySource + 'static,
+        frecency: Arc<FrecencyStore>,
+    ) -> Self {
+        Self::new_impl(source, frecency, None)
     }
 }
 
-fn resolve_icon_path(name: &str) -> Option<String> {
+fn initials(name_lc: &str) -> String {
-    if name.starts_with('/') && Path::new(name).exists() {
+    name_lc
-        return Some(name.to_string());
+        .split_whitespace()
-    }
+        .filter_map(|w| w.chars().next())
-    let candidates = [
+        .collect()
-        format!("/usr/share/pixmaps/{name}.png"),
-        format!("/usr/share/pixmaps/{name}.svg"),
-        format!("/usr/share/icons/hicolor/48x48/apps/{name}.png"),
-        format!("/usr/share/icons/hicolor/scalable/apps/{name}.svg"),
-    ];
-    candidates.into_iter().find(|p| Path::new(p).exists())
 }
 
-fn score_match(name_lc: &str, query_lc: &str) -> Option<u32> {
+fn score_match(name: &str, query: &str) -> Option<u32> {
-    if name_lc == query_lc {
+    use nucleo_matcher::{
-        Some(100)
+        Config, Matcher, Utf32Str,
-    } else if name_lc.starts_with(query_lc) {
+        pattern::{CaseMatching, Normalization, Pattern},
-        Some(80)
+    };
-    } else if name_lc.contains(query_lc) {
+
-        Some(60)
+    let mut matcher = Matcher::new(Config::DEFAULT);
+    let pattern = Pattern::parse(query, CaseMatching::Ignore, Normalization::Smart);
+
+    let mut name_chars: Vec<char> = name.chars().collect();
+    let haystack = Utf32Str::new(name, &mut name_chars);
+    let score = pattern.score(haystack, &mut matcher);
+
+    if let Some(s) = score {
+        let name_lc = name.to_lowercase();
+        let query_lc = query.to_lowercase();
+        let bonus: u32 = if initials(&name_lc).starts_with(&query_lc) {
+            20
+        } else {
+            0
+        };
+        Some(s.saturating_add(bonus))
     } else {
         None
     }
 }
 
+pub(crate) fn humanize_category(s: &str) -> String {
+    let mut result = String::new();
+    for ch in s.chars() {
+        if ch.is_uppercase() && !result.is_empty() {
+            result.push(' ');
+        }
+        result.push(ch);
+    }
+    result
+}
+
 #[async_trait]
 impl Plugin for AppsPlugin {
-    fn name(&self) -> PluginName {
+    fn name(&self) -> &str {
         "apps"
     }
 
+    fn on_selected(&self, id: &ResultId) {
+        self.frecency.record(id.as_str());
+    }
+
     async fn search(&self, query: &str) -> Vec<SearchResult> {
+        let entries = self.entries.read().unwrap();
         if query.is_empty() {
-            return vec![];
+            return self
+                .frecency
+                .top_ids(5)
+                .iter()
+                .filter_map(|id| {
+                    let e = entries.get(id)?;
+                    let score = self.frecency.frecency_score(id).max(1);
+                    Some(SearchResult {
+                        id: ResultId::new(id),
+                        title: ResultTitle::new(e.name.as_str()),
+                        description: e.category.clone(),
+                        icon: e.icon.clone(),
+                        score: Score::new(score),
+                        action: LaunchAction::SpawnProcess(e.exec.clone()),
+                    })
+                })
+                .collect();
         }
+
         let query_lc = query.to_lowercase();
-        self.entries
+        entries
-            .iter()
+            .values()
             .filter_map(|e| {
-                score_match(&e.name_lc, &query_lc).map(|score| SearchResult {
+                let score = score_match(e.name.as_str(), query).or_else(|| {
-                    id: ResultId::new(format!("app-{}", e.name.as_str())),
+                    e.keywords_lc
+                        .iter()
+                        .any(|k| k.contains(&query_lc))
+                        .then_some(50)
+                })?;
+                Some(SearchResult {
+                    id: ResultId::new(&e.id),
                     title: ResultTitle::new(e.name.as_str()),
-                    description: None,
+                    description: e.category.clone(),
                     icon: e.icon.clone(),
                     score: Score::new(score),
-                    on_execute: Arc::clone(&e.on_execute),
+                    action: LaunchAction::SpawnProcess(e.exec.clone()),
                 })
             })
             .collect()
     }
 }
 
-// --- Filesystem source ---
-
-pub struct FsDesktopEntrySource;
-
-impl FsDesktopEntrySource {
-    pub fn new() -> Self {
-        Self
-    }
-}
-
-impl Default for FsDesktopEntrySource {
-    fn default() -> Self {
-        Self::new()
-    }
-}
-
-impl DesktopEntrySource for FsDesktopEntrySource {
-    fn entries(&self) -> Vec<DesktopEntry> {
-        let mut dirs = Vec::new();
-        if let Ok(xdg) = xdg::BaseDirectories::new() {
-            dirs.push(xdg.get_data_home().join("applications"));
-            for d in xdg.get_data_dirs() {
-                dirs.push(d.join("applications"));
-            }
-        }
-        let mut entries = Vec::new();
-        for dir in &dirs {
-            if let Ok(read_dir) = std::fs::read_dir(dir) {
-                for entry in read_dir.flatten() {
-                    let path = entry.path();
-                    if path.extension().and_then(|e| e.to_str()) != Some("desktop") {
-                        continue;
-                    }
-                    if let Some(de) = parse_desktop_file(&path) {
-                        entries.push(de);
-                    }
-                }
-            }
-        }
-        entries
-    }
-}
-
-fn parse_desktop_file(path: &Path) -> Option<DesktopEntry> {
-    let content = std::fs::read_to_string(path).ok()?;
-    let mut in_section = false;
-    let mut name: Option<String> = None;
-    let mut exec: Option<String> = None;
-    let mut icon: Option<String> = None;
-    let mut is_application = false;
-    let mut no_display = false;
-
-    for line in content.lines() {
-        let line = line.trim();
-        if line == "[Desktop Entry]" {
-            in_section = true;
-            continue;
-        }
-        if line.starts_with('[') {
-            in_section = false;
-            continue;
-        }
-        if !in_section || line.starts_with('#') || line.is_empty() {
-            continue;
-        }
-        if let Some((key, value)) = line.split_once('=') {
-            match key.trim() {
-                "Name" if name.is_none() => name = Some(value.trim().to_string()),
-                "Exec" if exec.is_none() => exec = Some(value.trim().to_string()),
-                "Icon" if icon.is_none() => icon = Some(value.trim().to_string()),
-                "Type" if !is_application => is_application = value.trim() == "Application",
-                "NoDisplay" => no_display = value.trim().eq_ignore_ascii_case("true"),
-                _ => {}
-            }
-        }
-    }
-
-    if !is_application || no_display {
-        return None;
-    }
-
-    let exec_clean: String = exec?
-        .split_whitespace()
-        .filter(|s| !s.starts_with('%'))
-        .fold(String::new(), |mut acc, s| {
-            if !acc.is_empty() {
-                acc.push(' ');
-            }
-            acc.push_str(s);
-            acc
-        });
-
-    Some(DesktopEntry {
-        name: AppName::new(name?),
-        exec: ExecCommand::new(exec_clean),
-        icon: icon.map(IconPath::new),
-    })
-}
-
 // --- Tests ---
 
 #[cfg(test)]
 mod tests {
     use super::*;
 
+    fn ephemeral_frecency() -> Arc<FrecencyStore> {
+        FrecencyStore::new_for_test()
+    }
+
     struct MockSource {
-        entries: Vec<(String, String)>, // (name, exec)
+        entries: Vec<(String, String, Option<String>, Vec<String>)>, // (name, exec, category, keywords)
     }
 
     impl MockSource {
@@ -274,7 +339,32 @@ mod tests {
             Self {
                 entries: entries
                     .into_iter()
-                    .map(|(n, e)| (n.to_string(), e.to_string()))
+                    .map(|(n, e)| (n.to_string(), e.to_string(), None, vec![]))
+                    .collect(),
+            }
+        }
+
+        fn with_categories(entries: Vec<(&str, &str, &str)>) -> Self {
+            Self {
+                entries: entries
+                    .into_iter()
+                    .map(|(n, e, c)| (n.to_string(), e.to_string(), Some(c.to_string()), vec![]))
+                    .collect(),
+            }
+        }
+
+        fn with_keywords(entries: Vec<(&str, &str, Vec<&str>)>) -> Self {
+            Self {
+                entries: entries
+                    .into_iter()
+                    .map(|(n, e, kw)| {
+                        (
+                            n.to_string(),
+                            e.to_string(),
+                            None,
+                            kw.into_iter().map(|s| s.to_string()).collect(),
+                        )
+                    })
                     .collect(),
             }
         }
@@ -284,10 +374,12 @@ mod tests {
         fn entries(&self) -> Vec<DesktopEntry> {
             self.entries
                 .iter()
-                .map(|(name, exec)| DesktopEntry {
+                .map(|(name, exec, category, keywords)| DesktopEntry {
                     name: AppName::new(name.clone()),
                     exec: ExecCommand::new(exec.clone()),
                     icon: None,
+                    category: category.clone(),
+                    keywords: keywords.clone(),
                 })
                 .collect()
         }
@@ -295,23 +387,135 @@ mod tests {
 
     #[tokio::test]
     async fn apps_prefix_match() {
-        let source = MockSource::with(vec![("Firefox", "firefox")]);
+        let p = AppsPlugin::new_for_test(
-        let p = AppsPlugin::new(source);
+            MockSource::with(vec![("Firefox", "firefox")]),
+            ephemeral_frecency(),
+        );
         let results = p.search("fire").await;
         assert_eq!(results[0].title.as_str(), "Firefox");
     }
 
     #[tokio::test]
     async fn apps_no_match_returns_empty() {
-        let source = MockSource::with(vec![("Firefox", "firefox")]);
+        let p = AppsPlugin::new_for_test(
-        let p = AppsPlugin::new(source);
+            MockSource::with(vec![("Firefox", "firefox")]),
+            ephemeral_frecency(),
+        );
         assert!(p.search("zz").await.is_empty());
     }
 
     #[tokio::test]
-    async fn apps_empty_query_returns_empty() {
+    async fn apps_empty_query_no_frecency_returns_empty() {
-        let source = MockSource::with(vec![("Firefox", "firefox")]);
+        let p = AppsPlugin::new_for_test(
-        let p = AppsPlugin::new(source);
+            MockSource::with(vec![("Firefox", "firefox")]),
+            ephemeral_frecency(),
+        );
         assert!(p.search("").await.is_empty());
     }
+
+    #[test]
+    fn score_match_abbreviation() {
+        assert_eq!(initials("visual studio code"), "vsc");
+        assert!(score_match("visual studio code", "vsc").is_some());
+    }
+
+    #[test]
+    fn score_match_exact_beats_prefix() {
+        let exact = score_match("firefox", "firefox");
+        let prefix = score_match("firefox", "fire");
+        let abbrev = score_match("gnu firefox", "gf");
+        let substr = score_match("ice firefox", "fire");
+        assert!(exact.is_some());
+        assert!(prefix.is_some());
+        assert!(abbrev.is_some());
+        assert!(substr.is_some());
+        assert!(exact.unwrap() > prefix.unwrap());
+    }
+
+    #[tokio::test]
+    async fn apps_abbreviation_match() {
+        let p = AppsPlugin::new_for_test(
+            MockSource::with(vec![("Visual Studio Code", "code")]),
+            ephemeral_frecency(),
+        );
+        let results = p.search("vsc").await;
+        assert_eq!(results.len(), 1);
+        assert_eq!(results[0].title.as_str(), "Visual Studio Code");
+        assert!(results[0].score.value() > 0);
+    }
+
+    #[tokio::test]
+    async fn apps_keyword_match() {
+        let p = AppsPlugin::new_for_test(
+            MockSource::with_keywords(vec![("Code", "code", vec!["editor", "ide"])]),
+            ephemeral_frecency(),
+        );
+        let results = p.search("editor").await;
+        assert_eq!(results.len(), 1);
+        assert_eq!(results[0].score.value(), 50);
+    }
+
+    #[tokio::test]
+    async fn apps_fuzzy_typo_match() {
+        let p = AppsPlugin::new_for_test(
+            MockSource::with(vec![("Firefox", "firefox")]),
+            ephemeral_frecency(),
+        );
+        let results = p.search("frefox").await;
+        assert!(
+            !results.is_empty(),
+            "nucleo should fuzzy-match 'frefox' to 'Firefox'"
+        );
+        assert!(results[0].score.value() > 0);
+    }
+
+    #[test]
+    fn humanize_category_splits_camel_case() {
+        assert_eq!(humanize_category("TextEditor"), "Text Editor");
+        assert_eq!(humanize_category("WebBrowser"), "Web Browser");
+        assert_eq!(humanize_category("Development"), "Development");
+    }
+
+    #[tokio::test]
+    async fn apps_category_appears_in_description() {
+        let p = AppsPlugin::new_for_test(
+            MockSource::with_categories(vec![("Code", "code", "Text Editor")]),
+            ephemeral_frecency(),
+        );
+        let results = p.search("code").await;
+        assert_eq!(results[0].description.as_deref(), Some("Text Editor"));
+    }
+
+    #[tokio::test]
+    async fn apps_empty_query_returns_top_frecent() {
+        let frecency = ephemeral_frecency();
+        frecency.record("app-Code:code");
+        frecency.record("app-Code:code");
+        frecency.record("app-Firefox:firefox");
+        let p = AppsPlugin::new_for_test(
+            MockSource::with(vec![("Firefox", "firefox"), ("Code", "code")]),
+            frecency,
+        );
+        let results = p.search("").await;
+        assert_eq!(results.len(), 2);
+        assert_eq!(results[0].title.as_str(), "Code");
+    }
+
+    #[test]
+    fn apps_loads_from_cache_when_source_is_empty() {
+        let frecency = ephemeral_frecency();
+        let cache_file =
+            std::env::temp_dir().join(format!("k-launcher-test-{}.bin", std::process::id()));
+
+        // Build entries from a real source and save to temp path
+        let source = MockSource::with(vec![("Firefox", "firefox")]);
+        let entries = build_entries(&source, &frecency);
+        save_to_path(&cache_file, &entries);
+
+        // Load from temp path — should contain Firefox
+        let loaded = load_from_path(&cache_file).unwrap();
+        assert!(loaded.contains_key("app-Firefox:firefox"));
+
+        std::fs::remove_file(&cache_file).ok();
+    }
 }

crates/plugins/plugin-apps/src/linux.rs

@@ -0,0 +1,217 @@
+use std::path::Path;
+
+use crate::humanize_category;
+use crate::{AppName, DesktopEntry, DesktopEntrySource, ExecCommand, IconPath};
+
+pub struct FsDesktopEntrySource;
+
+impl FsDesktopEntrySource {
+    pub fn new() -> Self {
+        Self
+    }
+}
+
+impl Default for FsDesktopEntrySource {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl DesktopEntrySource for FsDesktopEntrySource {
+    fn entries(&self) -> Vec<DesktopEntry> {
+        let mut dirs = Vec::new();
+        let xdg = xdg::BaseDirectories::new();
+        if let Some(data_home) = xdg.get_data_home() {
+            dirs.push(data_home.join("applications"));
+        }
+        for d in xdg.get_data_dirs() {
+            dirs.push(d.join("applications"));
+        }
+        let mut entries = Vec::new();
+        for dir in &dirs {
+            if let Ok(read_dir) = std::fs::read_dir(dir) {
+                for entry in read_dir.flatten() {
+                    let path = entry.path();
+                    if path.extension().and_then(|e| e.to_str()) != Some("desktop") {
+                        continue;
+                    }
+                    if let Some(de) = parse_desktop_file(&path) {
+                        entries.push(de);
+                    }
+                }
+            }
+        }
+        entries
+    }
+}
+
+pub(crate) fn clean_exec(exec: &str) -> String {
+    // Tokenize respecting double-quoted strings, then filter field codes.
+    let mut tokens: Vec<String> = Vec::new();
+    let mut chars = exec.chars().peekable();
+
+    while let Some(&ch) = chars.peek() {
+        if ch.is_whitespace() {
+            chars.next();
+            continue;
+        }
+        if ch == '"' {
+            // Consume opening quote
+            chars.next();
+            let mut token = String::from('"');
+            while let Some(&c) = chars.peek() {
+                chars.next();
+                if c == '"' {
+                    token.push('"');
+                    break;
+                }
+                token.push(c);
+            }
+            // Strip embedded field codes like %f inside the quoted string
+            // (between the quotes, before re-assembling)
+            let inner = &token[1..token.len().saturating_sub(1)];
+            let cleaned_inner: String = inner
+                .split_whitespace()
+                .filter(|s| !is_field_code(s))
+                .collect::<Vec<_>>()
+                .join(" ");
+            tokens.push(format!("\"{cleaned_inner}\""));
+        } else {
+            let mut token = String::new();
+            while let Some(&c) = chars.peek() {
+                if c.is_whitespace() {
+                    break;
+                }
+                chars.next();
+                token.push(c);
+            }
+            if !is_field_code(&token) {
+                tokens.push(token);
+            }
+        }
+    }
+
+    tokens.join(" ")
+}
+
+fn is_field_code(s: &str) -> bool {
+    let b = s.as_bytes();
+    b.len() == 2 && b[0] == b'%' && b[1].is_ascii_alphabetic()
+}
+
+pub fn resolve_icon_path(name: &str) -> Option<String> {
+    if name.starts_with('/') && Path::new(name).exists() {
+        return Some(name.to_string());
+    }
+    // Try linicon freedesktop theme traversal
+    let themes = ["hicolor", "Adwaita", "breeze", "Papirus"];
+    for theme in &themes {
+        if let Some(icon_path) = linicon::lookup_icon(name)
+            .from_theme(theme)
+            .with_size(48)
+            .find_map(|r| r.ok())
+        {
+            return Some(icon_path.path.to_string_lossy().into_owned());
+        }
+    }
+    // Fallback to pixmaps
+    let candidates = [
+        format!("/usr/share/pixmaps/{name}.png"),
+        format!("/usr/share/pixmaps/{name}.svg"),
+    ];
+    candidates.into_iter().find(|p| Path::new(p).exists())
+}
+
+fn parse_desktop_file(path: &Path) -> Option<DesktopEntry> {
+    let content = std::fs::read_to_string(path).ok()?;
+    let mut in_section = false;
+    let mut name: Option<String> = None;
+    let mut exec: Option<String> = None;
+    let mut icon: Option<String> = None;
+    let mut category: Option<String> = None;
+    let mut keywords: Vec<String> = Vec::new();
+    let mut is_application = false;
+    let mut no_display = false;
+
+    for line in content.lines() {
+        let line = line.trim();
+        if line == "[Desktop Entry]" {
+            in_section = true;
+            continue;
+        }
+        if line.starts_with('[') {
+            in_section = false;
+            continue;
+        }
+        if !in_section || line.starts_with('#') || line.is_empty() {
+            continue;
+        }
+        if let Some((key, value)) = line.split_once('=') {
+            match key.trim() {
+                "Name" if name.is_none() => name = Some(value.trim().to_string()),
+                "Exec" if exec.is_none() => exec = Some(value.trim().to_string()),
+                "Icon" if icon.is_none() => icon = Some(value.trim().to_string()),
+                "Type" if !is_application => is_application = value.trim() == "Application",
+                "NoDisplay" => no_display = value.trim().eq_ignore_ascii_case("true"),
+                "Categories" if category.is_none() => {
+                    category = value
+                        .trim()
+                        .split(';')
+                        .find(|s| !s.is_empty())
+                        .map(|s| humanize_category(s.trim()));
+                }
+                "Keywords" if keywords.is_empty() => {
+                    keywords = value
+                        .trim()
+                        .split(';')
+                        .filter(|s| !s.is_empty())
+                        .map(|s| s.trim().to_string())
+                        .collect();
+                }
+                _ => {}
+            }
+        }
+    }
+
+    if !is_application || no_display {
+        return None;
+    }
+
+    let exec_clean: String = clean_exec(&exec?);
+
+    Some(DesktopEntry {
+        name: AppName::new(name?),
+        exec: ExecCommand::new(exec_clean),
+        icon: icon.map(IconPath::new),
+        category,
+        keywords,
+    })
+}
+
+#[cfg(test)]
+mod exec_tests {
+    use super::clean_exec;
+
+    #[test]
+    fn strips_bare_field_code() {
+        assert_eq!(clean_exec("app --file %f"), "app --file");
+    }
+
+    #[test]
+    fn strips_multiple_field_codes() {
+        assert_eq!(clean_exec("app %U --flag"), "app --flag");
+    }
+
+    #[test]
+    fn preserves_quoted_value() {
+        assert_eq!(
+            clean_exec(r#"app --arg="value" %U"#),
+            r#"app --arg="value""#
+        );
+    }
+
+    #[test]
+    fn handles_plain_exec() {
+        assert_eq!(clean_exec("firefox"), "firefox");
+    }
+}

crates/plugins/plugin-apps/src/main.rs

@@ -1 +0,0 @@
-fn main() {}

crates/plugins/plugin-calc/Cargo.toml

@@ -7,12 +7,8 @@ edition = "2024"
 name = "plugin_calc"
 path = "src/lib.rs"
 
-[[bin]]
-name = "plugin-calc"
-path = "src/main.rs"
-
 [dependencies]
 async-trait = { workspace = true }
-evalexpr = "11"
+evalexpr = "13"
 k-launcher-kernel = { path = "../../k-launcher-kernel" }
 tokio = { workspace = true }

crates/plugins/plugin-calc/src/lib.rs

@@ -1,7 +1,7 @@
-use std::sync::Arc;
-
 use async_trait::async_trait;
-use k_launcher_kernel::{Plugin, PluginName, ResultId, ResultTitle, Score, SearchResult};
+use evalexpr::eval_number_with_context;
+use k_launcher_kernel::{LaunchAction, Plugin, ResultId, ResultTitle, Score, SearchResult};
+use std::sync::LazyLock;
 
 pub struct CalcPlugin;
 
@@ -17,18 +17,54 @@ impl Default for CalcPlugin {
     }
 }
 
+fn strip_numeric_separators(expr: &str) -> String {
+    expr.replace('_', "")
+}
+
+const MATH_FNS: &[&str] = &[
+    "sqrt", "sin", "cos", "tan", "asin", "acos", "atan", "ln", "log2", "log10", "exp", "abs",
+    "ceil", "floor", "round",
+];
+
 fn should_eval(query: &str) -> bool {
-    query
+    let q = query.strip_prefix('=').unwrap_or(query);
-        .chars()
+    q.chars()
         .next()
         .map(|c| c.is_ascii_digit() || c == '(' || c == '-')
         .unwrap_or(false)
         || query.starts_with('=')
+        || MATH_FNS.iter().any(|f| q.starts_with(f))
 }
 
+static MATH_CTX: LazyLock<evalexpr::HashMapContext<evalexpr::DefaultNumericTypes>> = LazyLock::new(
+    || {
+        use evalexpr::*;
+        context_map! {
+            "pi" => float std::f64::consts::PI,
+            "e"  => float std::f64::consts::E,
+            "sqrt"  => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.sqrt()))),
+            "sin"   => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.sin()))),
+            "cos"   => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.cos()))),
+            "tan"   => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.tan()))),
+            "asin"  => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.asin()))),
+            "acos"  => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.acos()))),
+            "atan"  => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.atan()))),
+            "ln"    => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.ln()))),
+            "log2"  => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.log2()))),
+            "log10" => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.log10()))),
+            "exp"   => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.exp()))),
+            "abs"   => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.abs()))),
+            "ceil"  => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.ceil()))),
+            "floor" => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.floor()))),
+            "round" => Function::new(|a: &Value<DefaultNumericTypes>| Ok(Value::from_float(a.as_number()?.round())))
+        }
+        .expect("static math context must be valid")
+    },
+);
+
 #[async_trait]
 impl Plugin for CalcPlugin {
-    fn name(&self) -> PluginName {
+    fn name(&self) -> &str {
         "calc"
     }
 
@@ -36,21 +72,24 @@ impl Plugin for CalcPlugin {
         if !should_eval(query) {
             return vec![];
         }
-        let expr = query.strip_prefix('=').unwrap_or(query);
+        let raw = query.strip_prefix('=').unwrap_or(query);
-        match evalexpr::eval_number(expr) {
+        let expr_owned = strip_numeric_separators(raw);
+        let expr = expr_owned.as_str();
+        match eval_number_with_context(expr, &*MATH_CTX) {
             Ok(n) if n.is_finite() => {
-                let display = if n.fract() == 0.0 {
+                let value_str = if n.fract() == 0.0 {
-                    format!("= {}", n as i64)
+                    format!("{}", n as i64)
                 } else {
-                    format!("= {n}")
+                    format!("{n}")
                 };
+                let display = format!("= {value_str}");
                 vec![SearchResult {
                     id: ResultId::new("calc-result"),
                     title: ResultTitle::new(display),
-                    description: None,
+                    description: Some(format!("{expr_owned} · Enter to copy")),
                     icon: None,
                     score: Score::new(90),
-                    on_execute: Arc::new(|| {}),
+                    action: LaunchAction::CopyToClipboard(value_str),
                 }]
             }
             _ => vec![],
@@ -80,4 +119,36 @@ mod tests {
         let p = CalcPlugin::new();
         assert!(p.search("1/0").await.is_empty());
     }
+
+    #[tokio::test]
+    async fn calc_sqrt() {
+        let p = CalcPlugin::new();
+        let results = p.search("sqrt(9)").await;
+        assert_eq!(results[0].title.as_str(), "= 3");
+    }
+
+    #[tokio::test]
+    async fn calc_sin_pi() {
+        let p = CalcPlugin::new();
+        let results = p.search("sin(pi)").await;
+        assert!(!results.is_empty());
+        let title = results[0].title.as_str();
+        let val: f64 = title.trim_start_matches("= ").parse().unwrap();
+        assert!(val.abs() < 1e-10, "sin(pi) should be near zero, got {val}");
+    }
+
+    #[tokio::test]
+    async fn calc_underscore_separator() {
+        let p = CalcPlugin::new();
+        let results = p.search("1_000 * 2").await;
+        assert_eq!(results[0].title.as_str(), "= 2000");
+        assert_eq!(
+            results[0].description.as_deref(),
+            Some("1000 * 2 · Enter to copy")
+        );
+        assert!(matches!(
+            &results[0].action,
+            LaunchAction::CopyToClipboard(v) if v == "2000"
+        ));
+    }
 }

crates/plugins/plugin-calc/src/main.rs

@@ -1 +0,0 @@
-fn main() {}

crates/plugins/plugin-cmd/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "plugin-cmd"
+version = "0.1.0"
+edition = "2024"
+
+[lib]
+name = "plugin_cmd"
+path = "src/lib.rs"
+
+[dependencies]
+async-trait = { workspace = true }
+k-launcher-kernel = { path = "../../k-launcher-kernel" }
+
+[dev-dependencies]
+tokio = { workspace = true }

crates/plugins/plugin-cmd/src/lib.rs

@@ -0,0 +1,69 @@
+use async_trait::async_trait;
+use k_launcher_kernel::{LaunchAction, Plugin, ResultId, ResultTitle, Score, SearchResult};
+
+pub struct CmdPlugin;
+
+impl CmdPlugin {
+    pub fn new() -> Self {
+        Self
+    }
+}
+
+impl Default for CmdPlugin {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+#[async_trait]
+impl Plugin for CmdPlugin {
+    fn name(&self) -> &str {
+        "cmd"
+    }
+
+    async fn search(&self, query: &str) -> Vec<SearchResult> {
+        let Some(rest) = query.strip_prefix('>') else {
+            return vec![];
+        };
+        let cmd = rest.trim();
+        if cmd.is_empty() {
+            return vec![];
+        }
+        vec![SearchResult {
+            id: ResultId::new(format!("cmd-{cmd}")),
+            title: ResultTitle::new(format!("Run: {cmd}")),
+            description: None,
+            icon: None,
+            score: Score::new(95),
+            action: LaunchAction::SpawnInTerminal(cmd.to_string()),
+        }]
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[tokio::test]
+    async fn cmd_prefix_triggers() {
+        let p = CmdPlugin::new();
+        let results = p.search("> echo hello").await;
+        assert_eq!(results.len(), 1);
+        assert_eq!(results[0].title.as_str(), "Run: echo hello");
+        assert_eq!(results[0].score.value(), 95);
+    }
+
+    #[tokio::test]
+    async fn cmd_empty_remainder_returns_empty() {
+        let p = CmdPlugin::new();
+        assert!(p.search(">").await.is_empty());
+        assert!(p.search(">   ").await.is_empty());
+    }
+
+    #[tokio::test]
+    async fn cmd_no_prefix_returns_empty() {
+        let p = CmdPlugin::new();
+        assert!(p.search("echo hello").await.is_empty());
+        assert!(p.search("firefox").await.is_empty());
+    }
+}

crates/plugins/plugin-files/Cargo.toml

@@ -3,4 +3,11 @@ name = "plugin-files"
 version = "0.1.0"
 edition = "2024"
 
+[lib]
+name = "plugin_files"
+path = "src/lib.rs"
+
 [dependencies]
+async-trait = { workspace = true }
+k-launcher-kernel = { path = "../../k-launcher-kernel" }
+tokio = { workspace = true }

crates/plugins/plugin-files/src/lib.rs

@@ -0,0 +1,109 @@
+mod platform;
+
+use std::path::Path;
+
+use async_trait::async_trait;
+use k_launcher_kernel::{LaunchAction, Plugin, ResultId, ResultTitle, Score, SearchResult};
+
+pub struct FilesPlugin;
+
+impl FilesPlugin {
+    pub fn new() -> Self {
+        Self
+    }
+}
+
+impl Default for FilesPlugin {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+fn expand_query(query: &str) -> Option<String> {
+    if query.starts_with("~/") {
+        let home = platform::home_dir()?;
+        Some(format!("{}{}", home, &query[1..]))
+    } else if query.starts_with('/') {
+        Some(query.to_string())
+    } else {
+        None
+    }
+}
+
+#[async_trait]
+impl Plugin for FilesPlugin {
+    fn name(&self) -> &str {
+        "files"
+    }
+
+    async fn search(&self, query: &str) -> Vec<SearchResult> {
+        let expanded = match expand_query(query) {
+            Some(p) => p,
+            None => return vec![],
+        };
+        let path = Path::new(&expanded);
+        let (parent, prefix) = if path.is_dir() {
+            (path.to_path_buf(), String::new())
+        } else {
+            let parent = path.parent().unwrap_or(Path::new("/")).to_path_buf();
+            let prefix = path
+                .file_name()
+                .and_then(|n| n.to_str())
+                .unwrap_or("")
+                .to_lowercase();
+            (parent, prefix)
+        };
+
+        let entries = match std::fs::read_dir(&parent) {
+            Ok(e) => e,
+            Err(_) => return vec![],
+        };
+
+        entries
+            .filter_map(|e| e.ok())
+            .filter(|e| {
+                if prefix.is_empty() {
+                    return true;
+                }
+                e.file_name()
+                    .to_str()
+                    .map(|n| n.to_lowercase().starts_with(&prefix))
+                    .unwrap_or(false)
+            })
+            .take(20)
+            .map(|entry| {
+                let full_path = entry.path();
+                let name = entry.file_name().to_string_lossy().to_string();
+                let is_dir = full_path.is_dir();
+                let title = if is_dir { format!("{name}/") } else { name };
+                let path_str = full_path.to_string_lossy().to_string();
+                SearchResult {
+                    id: ResultId::new(&path_str),
+                    title: ResultTitle::new(title),
+                    description: Some(path_str.clone()),
+                    icon: None,
+                    score: Score::new(50),
+                    action: LaunchAction::OpenPath(path_str),
+                }
+            })
+            .collect()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[tokio::test]
+    async fn files_ignores_non_path_query() {
+        let p = FilesPlugin::new();
+        assert!(p.search("firefox").await.is_empty());
+    }
+
+    #[tokio::test]
+    async fn files_handles_root() {
+        let p = FilesPlugin::new();
+        let results = p.search("/").await;
+        assert!(!results.is_empty());
+    }
+}

crates/plugins/plugin-files/src/main.rs

@@ -1,3 +0,0 @@
-fn main() {
-    println!("Hello, world!");
-}

crates/plugins/plugin-files/src/platform.rs

@@ -0,0 +1,9 @@
+#[cfg(unix)]
+pub fn home_dir() -> Option<String> {
+    std::env::var("HOME").ok()
+}
+
+#[cfg(windows)]
+pub fn home_dir() -> Option<String> {
+    std::env::var("USERPROFILE").ok()
+}

crates/plugins/plugin-url/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "plugin-url"
+version = "0.1.0"
+edition = "2024"
+
+[[bin]]
+name = "k-launcher-plugin-url"
+path = "src/main.rs"
+
+[dependencies]
+serde = { workspace = true }
+serde_json = { workspace = true }

crates/plugins/plugin-url/src/main.rs

@@ -0,0 +1,130 @@
+use std::io::{self, BufRead, Write};
+
+use serde::{Deserialize, Serialize};
+
+#[derive(Deserialize)]
+struct Query {
+    query: String,
+}
+
+#[derive(Serialize)]
+struct Action {
+    r#type: &'static str,
+    path: String,
+}
+
+#[derive(Serialize)]
+struct Result {
+    id: &'static str,
+    title: &'static str,
+    description: String,
+    score: u32,
+    action: Action,
+}
+
+fn is_url(query: &str) -> bool {
+    query.starts_with("http://") || query.starts_with("https://") || query.starts_with("www.")
+}
+
+fn normalize(query: &str) -> String {
+    if query.starts_with("www.") {
+        format!("https://{query}")
+    } else {
+        query.to_string()
+    }
+}
+
+fn search(query: &str) -> Vec<Result> {
+    if !is_url(query) {
+        return vec![];
+    }
+    let url = normalize(query);
+    vec![Result {
+        id: "url-open",
+        title: "Open in Browser",
+        description: url.clone(),
+        score: 95,
+        action: Action {
+            r#type: "OpenPath",
+            path: url.clone(),
+        },
+    }]
+}
+
+fn main() -> io::Result<()> {
+    let stdin = io::stdin();
+    let stdout = io::stdout();
+    let mut out = stdout.lock();
+
+    for line in stdin.lock().lines() {
+        let line = line?;
+        let q: Query = match serde_json::from_str(&line) {
+            Ok(q) => q,
+            Err(_) => continue,
+        };
+        let results = search(&q.query);
+        writeln!(out, "{}", serde_json::to_string(&results).unwrap())?;
+        out.flush()?;
+    }
+    Ok(())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn is_url_https() {
+        assert!(is_url("https://example.com"));
+    }
+
+    #[test]
+    fn is_url_http() {
+        assert!(is_url("http://example.com"));
+    }
+
+    #[test]
+    fn is_url_www() {
+        assert!(is_url("www.foo.com"));
+    }
+
+    #[test]
+    fn is_url_plain() {
+        assert!(!is_url("firefox"));
+    }
+
+    #[test]
+    fn is_url_empty() {
+        assert!(!is_url(""));
+    }
+
+    #[test]
+    fn normalize_www() {
+        assert_eq!(normalize("www.foo.com"), "https://www.foo.com");
+    }
+
+    #[test]
+    fn normalize_https() {
+        assert_eq!(normalize("https://example.com"), "https://example.com");
+    }
+
+    #[test]
+    fn search_returns_result() {
+        let results = search("https://example.com");
+        assert_eq!(results.len(), 1);
+        assert_eq!(results[0].action.path, "https://example.com");
+    }
+
+    #[test]
+    fn search_returns_empty() {
+        assert!(search("firefox").is_empty());
+    }
+
+    #[test]
+    fn result_serializes() {
+        let results = search("https://example.com");
+        let json = serde_json::to_string(&results).unwrap();
+        assert!(json.contains("OpenPath"));
+        assert!(json.contains("https://example.com"));
+    }
+}

docs/configuration.md

@@ -0,0 +1,51 @@
+# Configuration
+
+Config file: `~/.config/k-launcher/config.toml`
+
+The file is optional — all fields have defaults and missing sections fall back to defaults automatically. Create it manually if you want to customize behavior.
+
+## Full Annotated Example
+
+```toml
+[window]
+width       = 600.0   # window width in logical pixels
+height      = 400.0   # window height in logical pixels
+decorations = false   # show window title bar / frame
+transparent = true    # allow background transparency
+resizable   = false   # allow manual resizing
+
+[appearance]
+# RGBA: r/g/b are 0–255 as floats, a is 0.0–1.0
+background_rgba  = [20.0, 20.0, 30.0, 0.9]    # main background
+border_rgba      = [229.0, 125.0, 33.0, 1.0]  # accent/border color
+border_width     = 1.0    # border thickness in pixels
+border_radius    = 8.0    # corner radius of the window
+search_font_size = 18.0   # font size of the search input
+title_size       = 15.0   # font size of result titles
+desc_size        = 12.0   # font size of result descriptions
+row_radius       = 4.0    # corner radius of result rows
+placeholder      = "Search..."  # search input placeholder text
+
+[search]
+max_results = 8   # maximum results shown at once
+
+[plugins]
+calc  = true   # math expression evaluator
+cmd   = true   # shell command runner (> prefix)
+files = true   # filesystem browser (/ or ~/ prefix)
+apps  = true   # XDG application launcher
+
+# External (dynamic) plugins — repeat block for each plugin
+[[plugins.external]]
+name = "my-plugin"              # display name / identifier
+path = "/path/to/my-plugin"    # path to executable
+args = []                       # optional extra arguments
+```
+
+## RGBA Format
+
+Colors use `[r, g, b, a]` arrays where:
+- `r`, `g`, `b` — red, green, blue channels as floats **0.0–255.0**
+- `a` — alpha (opacity) as a float **0.0–1.0**
+
+Example — semi-transparent white: `[255.0, 255.0, 255.0, 0.5]`

docs/install.md

@@ -0,0 +1,57 @@
+# Installation
+
+## Prerequisites
+
+- **Rust** stable toolchain — install via [rustup](https://rustup.rs)
+- **git**
+- A **Wayland** or **X11** compositor (Linux)
+
+## Build from Source
+
+```bash
+git clone https://github.com/GKaszewski/k-launcher
+cd k-launcher
+cargo build --release
+```
+
+Binary location: `target/release/k-launcher`
+
+### Optional: install to PATH
+
+```bash
+cp target/release/k-launcher ~/.local/bin/
+```
+
+Ensure `~/.local/bin` is in your `$PATH`.
+
+## Autostart
+
+### Hyprland
+
+Add to `~/.config/hypr/hyprland.conf`:
+
+```
+exec-once = k-launcher
+```
+
+### systemd user service
+
+Create `~/.config/systemd/user/k-launcher.service`:
+
+```ini
+[Unit]
+Description=k-launcher command palette
+
+[Service]
+ExecStart=%h/.local/bin/k-launcher
+Restart=on-failure
+
+[Install]
+WantedBy=graphical-session.target
+```
+
+Then enable it:
+
+```bash
+systemctl --user enable --now k-launcher
+```

docs/plugin-development.md

@@ -0,0 +1,222 @@
+# Plugin Development
+
+Plugins are queried concurrently — the kernel fans out every search to all enabled plugins and merges results by score.
+
+There are two kinds of plugins:
+
+- **External plugins** — executables that speak a JSON protocol over stdin/stdout. Any language, no compilation required. Recommended for community plugins.
+- **Built-in plugins** — Rust crates compiled into the binary. For performance-critical or tightly integrated plugins.
+
+---
+
+## External Plugins
+
+An external plugin is any executable that:
+
+1. Reads a JSON object from stdin (one line per query)
+2. Writes a JSON array of results to stdout (one line per response)
+
+### Protocol
+
+**Input** (one line, newline-terminated):
+```json
+{"query": "firefox"}
+```
+
+**Output** (one line, newline-terminated):
+```json
+[{"id":"app-firefox","title":"Firefox","score":80,"description":"Web Browser","action":{"type":"SpawnProcess","cmd":"firefox"}}]
+```
+
+The process is kept alive between queries — do **not** exit after each response.
+
+### Action types
+
+| `"type"` | Extra fields | Behavior |
+|----------|-------------|---------|
+| `SpawnProcess` | `"cmd"` | Launch process directly |
+| `CopyToClipboard` | `"text"` | Copy text to clipboard |
+| `OpenPath` | `"path"` | Open file/dir with xdg-open |
+
+### Optional result fields
+
+| Field | Type | Description |
+|-------|------|-------------|
+| `description` | `string` | Secondary line shown below title |
+| `icon` | `string` | Icon path (future use) |
+
+### Enabling an external plugin
+
+In `~/.config/k-launcher/config.toml`:
+
+```toml
+[[plugins.external]]
+name = "my-plugin"
+path = "/usr/lib/k-launcher/plugins/my-plugin"
+args = []        # optional
+```
+
+Multiple `[[plugins.external]]` blocks are supported.
+
+### Example: shell plugin
+
+```bash
+#!/usr/bin/env bash
+# A plugin that greets the user.
+while IFS= read -r line; do
+    query=$(echo "$line" | python3 -c "import sys,json; print(json.load(sys.stdin)['query'])")
+    if [[ "$query" == hello* ]]; then
+        echo '[{"id":"greet","title":"Hello, World!","score":80,"action":{"type":"CopyToClipboard","text":"Hello, World!"}}]'
+    else
+        echo '[]'
+    fi
+done
+```
+
+### Example: Python plugin
+
+```python
+#!/usr/bin/env python3
+import sys, json
+
+for line in sys.stdin:
+    query = json.loads(line)["query"]
+    results = []
+    if query.startswith("hello"):
+        results.append({
+            "id": "greet",
+            "title": "Hello, World!",
+            "score": 80,
+            "action": {"type": "CopyToClipboard", "text": "Hello, World!"},
+        })
+    print(json.dumps(results), flush=True)
+```
+
+---
+
+## Built-in Plugins (compiled-in)
+
+Built-in plugins implement the `Plugin` trait from `k-launcher-kernel` as Rust crates compiled into the binary.
+
+### 1. Create a new crate in the workspace
+
+```bash
+cargo new --lib crates/plugins/plugin-hello
+```
+
+Add it to the workspace root `Cargo.toml`:
+
+```toml
+[workspace]
+members = [
+    # ...existing members...
+    "crates/plugins/plugin-hello",
+]
+```
+
+### 2. Add dependencies
+
+`crates/plugins/plugin-hello/Cargo.toml`:
+
+```toml
+[dependencies]
+k-launcher-kernel = { path = "../../k-launcher-kernel" }
+async-trait = "0.1"
+```
+
+### 3. Implement the `Plugin` trait
+
+`crates/plugins/plugin-hello/src/lib.rs`:
+
+```rust
+use async_trait::async_trait;
+use k_launcher_kernel::{LaunchAction, Plugin, ResultId, ResultTitle, Score, SearchResult};
+
+pub struct HelloPlugin;
+
+impl HelloPlugin {
+    pub fn new() -> Self {
+        Self
+    }
+}
+
+#[async_trait]
+impl Plugin for HelloPlugin {
+    fn name(&self) -> &str {
+        "hello"
+    }
+
+    async fn search(&self, query: &str) -> Vec<SearchResult> {
+        if !query.starts_with("hello") {
+            return vec![];
+        }
+
+        vec![SearchResult {
+            id: ResultId::new("hello:world"),
+            title: ResultTitle::new("Hello, World!"),
+            description: Some("A greeting from the hello plugin".to_string()),
+            icon: None,
+            score: Score::new(80),
+            action: LaunchAction::CopyToClipboard("Hello, World!".to_string()),
+            on_select: None,
+        }]
+    }
+}
+```
+
+### 4. Wire up in main.rs
+
+`crates/k-launcher/src/main.rs` — add alongside the existing plugins:
+
+```rust
+use plugin_hello::HelloPlugin;
+
+// inside main():
+plugins.push(Arc::new(HelloPlugin::new()));
+```
+
+Also add the dependency to `crates/k-launcher/Cargo.toml`:
+
+```toml
+[dependencies]
+plugin-hello = { path = "../plugins/plugin-hello" }
+```
+
+---
+
+## Reference
+
+### `SearchResult` Fields
+
+| Field | Type | Description |
+|-------|------|-------------|
+| `id` | `ResultId` | Unique stable ID (e.g. `"apps:firefox"`) |
+| `title` | `ResultTitle` | Primary display text |
+| `description` | `Option<String>` | Secondary line shown below title |
+| `icon` | `Option<String>` | Icon name or path (currently unused in renderer) |
+| `score` | `Score(u32)` | Sort priority — higher wins |
+| `action` | `LaunchAction` | What happens on `Enter` |
+| `on_select` | `Option<Arc<dyn Fn()>>` | Optional side-effect on selection (e.g. frecency bump) |
+
+### `LaunchAction` Variants
+
+| Variant | Behavior |
+|---------|----------|
+| `SpawnProcess(String)` | Launch a process directly (e.g. app exec string) |
+| `SpawnInTerminal(String)` | Run command inside a terminal emulator |
+| `OpenPath(String)` | Open a file or directory with `xdg-open` |
+| `CopyToClipboard(String)` | Copy text to clipboard |
+| `Custom(Arc<dyn Fn()>)` | Arbitrary closure |
+
+### Scoring Guidance
+
+| Score range | Match type |
+|-------------|-----------|
+| 100 | Exact match |
+| 90–99 | Calc/command result (always relevant) |
+| 80 | Prefix match |
+| 70 | Abbreviation match |
+| 60 | Substring match |
+| 50 | Keyword / loose match |
+
+The kernel sorts all results from all plugins by score descending and truncates to `max_results` (default: 8).

docs/usage.md

@@ -0,0 +1,50 @@
+# Usage
+
+## Running
+
+```bash
+k-launcher
+```
+
+## Keybinds
+
+| Key | Action |
+|-----|--------|
+| Type | Filter results |
+| `↑` / `↓` | Navigate list |
+| `Enter` | Launch selected result |
+| `Escape` | Close launcher |
+
+## Built-in Plugins
+
+### Apps
+
+Type any app name to search installed applications. An empty query shows your most frequently launched apps (frecency-ranked top results).
+
+### Calc
+
+Type a math expression — the result appears instantly and is copied to clipboard on `Enter`.
+
+```
+2^10 + 5       → 1029
+sqrt(144)      → 12
+sin(pi / 2)   → 1
+```
+
+### Shell Command
+
+Prefix your input with `>` to run a shell command in a terminal:
+
+```
+> echo hello
+> htop
+```
+
+### Files
+
+Start your query with `/` or `~/` to browse the filesystem:
+
+```
+/etc/hosts
+~/Documents/report.pdf
+```

packaging/aur/.SRCINFO

@@ -0,0 +1,15 @@
+pkgbase = k-launcher-bin
+	pkgdesc = GPU-accelerated command palette launcher for Linux (Wayland/X11)
+	pkgver = 0.1.0
+	pkgrel = 1
+	url = https://github.com/GKaszewski/k-launcher
+	arch = x86_64
+	license = MIT
+	depends = wayland
+	depends = libxkbcommon
+	provides = k-launcher
+	conflicts = k-launcher
+	source = k-launcher-0.1.0::https://github.com/GKaszewski/k-launcher/releases/download/v0.1.0/k-launcher
+	sha256sums = SKIP
+
+pkgname = k-launcher-bin

packaging/aur/PKGBUILD

@@ -0,0 +1,17 @@
+# Maintainer: k-launcher contributors
+pkgname=k-launcher-bin
+pkgver=0.1.0
+pkgrel=1
+pkgdesc="GPU-accelerated command palette launcher for Linux (Wayland/X11)"
+arch=('x86_64')
+url="https://github.com/GKaszewski/k-launcher"
+license=('MIT')
+depends=('wayland' 'libxkbcommon')
+provides=('k-launcher')
+conflicts=('k-launcher')
+source=("k-launcher-${pkgver}::https://github.com/GKaszewski/k-launcher/releases/download/v${pkgver}/k-launcher")
+sha256sums=('SKIP')
+
+package() {
+    install -Dm755 "k-launcher-${pkgver}" "${pkgdir}/usr/bin/k-launcher"
+}

packaging/systemd/k-launcher.service

@@ -0,0 +1,11 @@
+[Unit]
+Description=k-launcher command palette daemon
+After=graphical-session.target
+
+[Service]
+Type=simple
+ExecStart=/usr/bin/k-launcher
+Restart=on-failure
+
+[Install]
+WantedBy=graphical-session.target

packaging/systemd/k-launcher.socket

@@ -0,0 +1,8 @@
+[Unit]
+Description=k-launcher IPC socket
+
+[Socket]
+ListenStream=%t/k-launcher.sock
+
+[Install]
+WantedBy=sockets.target