diff --git a/alarm_widg/Cargo.toml b/alarm_widg/Cargo.toml
index 6036452..7fec542 100644
--- a/alarm_widg/Cargo.toml
+++ b/alarm_widg/Cargo.toml
@@ -5,6 +5,7 @@ edition = "2024"
 
 [dependencies]
 alarm_widg_config = {path = "../alarm_widg_config"}
+chrono = "0.4.44"
 dirs = "6.0.0"
 i-slint-backend-winit = "1.15.1"
 slint = "1.15.1"
diff --git a/alarm_widg/src/main.rs b/alarm_widg/src/main.rs
index 22e945a..7227255 100644
--- a/alarm_widg/src/main.rs
+++ b/alarm_widg/src/main.rs
@@ -1,6 +1,78 @@
 mod show_popup;
 
-fn main() -> Result<(), Box<dyn std::error::Error>> {
-    show_popup::show_popup()?;
+use alarm_widg_config::Config;
+use chrono::{Datelike, Local, Timelike};
+use show_popup::{PopupData, show_popup};
+use std::{collections::HashSet, thread, time::Duration};
+
+use alarm_widg_config::Alarm;
+use chrono::NaiveDate;
+
+fn alarm_matches_today(alarm: &Alarm, today: NaiveDate) -> bool {
+    if let Some(days) = &alarm.days {
+        let weekday = today.weekday().num_days_from_sunday() as u8;
+        return days.contains(&weekday);
+    }
+
+    if let Some(dates) = &alarm.dates {
+        return dates.contains(&today);
+    }
+
+    false
+}
+
+fn trigger_alarm(alarm: &Alarm) -> Result<(), Box<dyn std::error::Error>> {
+    println!("Triggering alarm: {}", alarm.title);
+
+    let popup = PopupData {
+        title: alarm.title.clone(),
+        time: alarm.time.format("%I:%M%p").to_string(),
+        color: alarm.color.unwrap_or(0xff232323),
+    };
+
+    // UI must run on main thread in many backends.
+    // For now we block until closed.
+    show_popup(popup)?;
+
     Ok(())
 }
+
+fn run_scheduler(config: Config) -> Result<(), Box<dyn std::error::Error>> {
+    println!("alarm_widg scheduler started");
+
+    // prevents duplicate triggers within same minute
+    let mut fired: HashSet<(String, i64)> = HashSet::new();
+
+    loop {
+        let now = Local::now();
+
+        for alarm in &config.alarms {
+            if !alarm.enabled {
+                continue;
+            }
+
+            if !alarm_matches_today(alarm, now.date_naive()) {
+                continue;
+            }
+
+            if alarm.time.hour() == now.hour() && alarm.time.minute() == now.minute() {
+                let key = (alarm.title.clone(), now.timestamp() / 60);
+
+                if fired.insert(key) {
+                    trigger_alarm(alarm)?;
+                }
+            }
+        }
+
+        // keep memory bounded
+        fired.retain(|(_, minute)| now.timestamp() / 60 - *minute < 5);
+
+        thread::sleep(Duration::from_secs(1));
+    }
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let config = Config::load()?;
+
+    run_scheduler(config)
+}
diff --git a/alarm_widg/src/show_popup.rs b/alarm_widg/src/show_popup.rs
index 71fd3e2..adcd9d6 100644
--- a/alarm_widg/src/show_popup.rs
+++ b/alarm_widg/src/show_popup.rs
@@ -10,24 +10,27 @@ use i_slint_backend_winit::{
 
 slint::include_modules!();
 
-fn set_ui_props(ui: &MainWindow) {
-	// Window placement
-    ui.window().set_position(LogicalPosition::new(200.0, 35.0));
+pub struct PopupData {
+    pub title: String,
+    pub time: String,
+    pub color: u32,
+}
 
-    // Window size
+fn set_ui_props(ui: &MainWindow, data: &PopupData) {
+    ui.window().set_position(LogicalPosition::new(200.0, 35.0));
     ui.window().set_size(LogicalSize::new(300.0, 124.0));
 
-	// Alarm properties
-    ui.set_alarm_name(SharedString::from("Sample alarm"));
-    ui.set_alarm_time(SharedString::from("11:45AM"));
-    ui.set_alarm_color(Color::from_argb_encoded(0xff232323));
+    ui.set_alarm_name(SharedString::from(data.title.clone()));
+    ui.set_alarm_time(SharedString::from(data.time.clone()));
+    ui.set_alarm_color(Color::from_argb_encoded(data.color));
+
     ui.set_popup_width(300);
     ui.set_popup_height(124);
     ui.set_default_font(SharedString::from("IosevkaTermSlab Nerd Font Mono"));
     ui.set_alarm_icon(SharedString::from("🕓"));
 }
 
-pub fn show_popup() -> Result<(), Box<dyn std::error::Error>> {
+pub fn show_popup(data: PopupData) -> Result<(), Box<dyn std::error::Error>> {
     // Closure to configure X11 window attributes before Slint creates the window.
     let window_attrs = |attrs: WindowAttributes| {
         attrs
@@ -49,7 +52,7 @@ pub fn show_popup() -> Result<(), Box<dyn std::error::Error>> {
     let ui = MainWindow::new()?;
 
     // Send the alarm data to the UI as properties
-    set_ui_props(&ui);
+    set_ui_props(&ui, &data);
 
     // Run the UI
     ui.run()?;
diff --git a/alarm_widg_config/Cargo.toml b/alarm_widg_config/Cargo.toml
index df04132..4d06a23 100644
--- a/alarm_widg_config/Cargo.toml
+++ b/alarm_widg_config/Cargo.toml
@@ -4,6 +4,8 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
+chrono = { version = "0.4.44", features = ["serde"] }
 dirs = "6.0.0"
 serde = { version = "1.0.228", features = ["derive"] }
+thiserror = "2.0.18"
 toml = "1.0.3"
diff --git a/alarm_widg_config/src/lib.rs b/alarm_widg_config/src/lib.rs
index b93cf3f..0a691f0 100644
--- a/alarm_widg_config/src/lib.rs
+++ b/alarm_widg_config/src/lib.rs
@@ -1,14 +1,169 @@
-pub fn add(left: u64, right: u64) -> u64 {
-    left + right
+use chrono::{NaiveDate, NaiveTime};
+use dirs::config_dir;
+use serde::Deserialize;
+use std::{fs, path::PathBuf};
+use thiserror::Error;
+
+const CONFIG_PATH: &str = "candywidgets/alarm-app/config.toml";
+
+// Errors
+
+#[derive(Debug, Error)]
+pub enum ConfigError {
+    #[error("config directory not found")]
+    NoConfigDir,
+
+    #[error("config file not found: {0}")]
+    MissingFile(PathBuf),
+
+    #[error("failed to read config: {0}")]
+    Io(#[from] std::io::Error),
+
+    #[error("toml parse error: {0}")]
+    Toml(#[from] toml::de::Error),
+
+    #[error("invalid alarm: {0}")]
+    Invalid(String),
 }
 
-#[cfg(test)]
-mod tests {
-    use super::*;
+// Public API Types
 
-    #[test]
-    fn it_works() {
-        let result = add(2, 2);
-        assert_eq!(result, 4);
+#[derive(Debug, Clone)]
+pub struct Config {
+    pub alarms: Vec<Alarm>,
+}
+
+#[derive(Debug, Clone)]
+pub struct Alarm {
+    pub title: String,
+    pub time: NaiveTime,
+    pub days: Option<Vec<u8>>,
+    pub dates: Option<Vec<NaiveDate>>,
+    pub color: Option<u32>,
+    pub enabled: bool,
+}
+
+// TOML Deserialization Layer
+// (separate from public types intentionally)
+
+#[derive(Debug, Deserialize)]
+struct RawConfig {
+    #[serde(default)]
+    alarm: Vec<RawAlarm>,
+}
+
+#[derive(Debug, Deserialize)]
+struct RawAlarm {
+    title: String,
+    time: String,
+
+    days: Option<Vec<u8>>,
+    dates: Option<Vec<String>>,
+
+    color: Option<String>,
+
+    #[serde(default = "default_enabled")]
+    enabled: bool,
+}
+
+fn default_enabled() -> bool {
+    true
+}
+
+// Loader
+
+impl Config {
+    pub fn load() -> Result<Self, ConfigError> {
+        let path = config_path()?;
+
+        if !path.exists() {
+            return Err(ConfigError::MissingFile(path));
+        }
+
+        let content = fs::read_to_string(&path)?;
+        let raw: RawConfig = toml::from_str(&content)?;
+
+        let alarms = raw
+            .alarm
+            .into_iter()
+            .map(Alarm::from_raw)
+            .collect::<Result<Vec<_>, _>>()?;
+
+        Ok(Self { alarms })
     }
 }
+
+// Conversion + Validation
+
+impl Alarm {
+    fn from_raw(raw: RawAlarm) -> Result<Self, ConfigError> {
+        // validate schedule
+        if raw.days.is_none() && raw.dates.is_none() {
+            return Err(ConfigError::Invalid(format!(
+                "alarm '{}' must specify 'days' or 'dates'",
+                raw.title
+            )));
+        }
+
+        // parse time
+        let time = NaiveTime::parse_from_str(&raw.time, "%H:%M").map_err(|_| {
+            ConfigError::Invalid(format!("invalid time '{}' in '{}'", raw.time, raw.title))
+        })?;
+
+        // validate days
+        if let Some(ref days) = raw.days {
+            for d in days {
+                if *d > 6 {
+                    return Err(ConfigError::Invalid(format!(
+                        "day '{}' out of range in '{}'",
+                        d, raw.title
+                    )));
+                }
+            }
+        }
+
+        // parse dates
+        let dates = match raw.dates {
+            Some(list) => {
+                let mut out = Vec::new();
+                for d in list {
+                    let parsed = NaiveDate::parse_from_str(&d, "%Y-%m-%d").map_err(|_| {
+                        ConfigError::Invalid(format!("invalid date '{}' in '{}'", d, raw.title))
+                    })?;
+                    out.push(parsed);
+                }
+                Some(out)
+            }
+            None => None,
+        };
+
+        // parse color (ARGB hex)
+        let color = match raw.color {
+            Some(c) => Some(parse_argb(&c)?),
+            None => None,
+        };
+
+        Ok(Self {
+            title: raw.title,
+            time,
+            days: raw.days,
+            dates,
+            color,
+            enabled: raw.enabled,
+        })
+    }
+}
+
+// Helpers
+
+fn config_path() -> Result<PathBuf, ConfigError> {
+    let base = config_dir().ok_or(ConfigError::NoConfigDir)?;
+    Ok(base.join(CONFIG_PATH))
+}
+
+fn parse_argb(input: &str) -> Result<u32, ConfigError> {
+    let cleaned = input.trim_start_matches('#');
+
+    u32::from_str_radix(cleaned, 16)
+        .map_err(|_| ConfigError::Invalid(format!("invalid ARGB color '{input}'")))
+}