diff --git a/src-tauri/src/commands.rs b/src-tauri/src/commands.rs
new file mode 100644
index 0000000..758f49f
--- /dev/null
+++ b/src-tauri/src/commands.rs
@@ -0,0 +1,66 @@
+use crate::models::{Config, ProfileSummary};
+
+#[tauri::command]
+pub fn load_config_command() -> Config {
+    Config {
+        default_model: None,
+        providers: indexmap::IndexMap::new(),
+        models: indexmap::IndexMap::new(),
+        raw_other: toml_edit::Table::new(),
+    }
+}
+
+#[tauri::command]
+pub fn save_config_command(_config: Config) -> Result<(), String> {
+    Ok(())
+}
+
+#[tauri::command]
+pub fn list_profiles() -> Vec<ProfileSummary> {
+    Vec::new()
+}
+
+#[tauri::command]
+pub fn load_profile(_filename: String) -> Config {
+    Config {
+        default_model: None,
+        providers: indexmap::IndexMap::new(),
+        models: indexmap::IndexMap::new(),
+        raw_other: toml_edit::Table::new(),
+    }
+}
+
+#[tauri::command]
+pub fn save_profile(_filename: String, _config: Config) -> Result<(), String> {
+    Ok(())
+}
+
+#[tauri::command]
+pub fn switch_profile(_filename: String) -> Result<Config, String> {
+    Ok(Config {
+        default_model: None,
+        providers: indexmap::IndexMap::new(),
+        models: indexmap::IndexMap::new(),
+        raw_other: toml_edit::Table::new(),
+    })
+}
+
+#[tauri::command]
+pub fn rename_profile(_old_filename: String, _new_name: String) -> Result<String, String> {
+    Ok(String::new())
+}
+
+#[tauri::command]
+pub fn delete_profile(_filename: String) -> Result<(), String> {
+    Ok(())
+}
+
+#[tauri::command]
+pub fn open_config_dir() -> Result<(), String> {
+    Ok(())
+}
+
+#[tauri::command]
+pub fn get_app_version() -> String {
+    env!("CARGO_PKG_VERSION").to_string()
+}
diff --git a/src-tauri/src/config_io.rs b/src-tauri/src/config_io.rs
new file mode 100644
index 0000000..e69de29
diff --git a/src-tauri/src/lib.rs b/src-tauri/src/lib.rs
index adad12a..eb36fa9 100644
--- a/src-tauri/src/lib.rs
+++ b/src-tauri/src/lib.rs
@@ -1,6 +1,24 @@
+pub mod commands;
+pub mod config_io;
+pub mod models;
+pub mod profile_manager;
+pub mod validators;
+
 pub fn run() {
     tauri::Builder::default()
         .plugin(tauri_plugin_shell::init())
+        .invoke_handler(tauri::generate_handler![
+            commands::load_config_command,
+            commands::save_config_command,
+            commands::list_profiles,
+            commands::load_profile,
+            commands::save_profile,
+            commands::switch_profile,
+            commands::rename_profile,
+            commands::delete_profile,
+            commands::open_config_dir,
+            commands::get_app_version,
+        ])
         .run(tauri::generate_context!())
         .expect("error while running tauri application");
 }
diff --git a/src-tauri/src/models.rs b/src-tauri/src/models.rs
new file mode 100644
index 0000000..bcadabe
--- /dev/null
+++ b/src-tauri/src/models.rs
@@ -0,0 +1,75 @@
+use indexmap::IndexMap;
+use serde::{Deserialize, Serialize};
+pub use toml_edit::Table;
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub enum ProviderType {
+    Kimi,
+    Anthropic,
+    Openai,
+    #[serde(rename = "openai_responses")]
+    OpenaiResponses,
+    #[serde(rename = "google-genai")]
+    GoogleGenai,
+    Vertexai,
+}
+
+impl ProviderType {
+    pub fn as_str(&self) -> &'static str {
+        match self {
+            ProviderType::Kimi => "kimi",
+            ProviderType::Anthropic => "anthropic",
+            ProviderType::Openai => "openai",
+            ProviderType::OpenaiResponses => "openai_responses",
+            ProviderType::GoogleGenai => "google-genai",
+            ProviderType::Vertexai => "vertexai",
+        }
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Provider {
+    pub name: String,
+    pub provider_type: ProviderType,
+    pub base_url: Option<String>,
+    pub api_key: Option<String>,
+    pub env: IndexMap<String, String>,
+    #[serde(skip)]
+    pub raw_other: Table,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Model {
+    pub alias: String,
+    pub provider: String,
+    pub model: String,
+    pub max_context_size: u64,
+    pub display_name: Option<String>,
+    #[serde(skip)]
+    pub raw_other: Table,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Config {
+    pub default_model: Option<String>,
+    pub providers: IndexMap<String, Provider>,
+    pub models: IndexMap<String, Model>,
+    #[serde(skip)]
+    pub raw_other: Table,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct ProfileSummary {
+    pub name: String,
+    pub filename: String,
+    pub is_active: bool,
+}
+
+#[derive(Debug, Clone)]
+pub struct Profile {
+    pub name: String,
+    pub filename: String,
+    pub config: Config,
+    pub is_active: bool,
+}
diff --git a/src-tauri/src/profile_manager.rs b/src-tauri/src/profile_manager.rs
new file mode 100644
index 0000000..e69de29
diff --git a/src-tauri/src/validators.rs b/src-tauri/src/validators.rs
new file mode 100644
index 0000000..e69de29