diff --git a/src-tauri/src/config.rs b/src-tauri/src/config.rs
index 1994406..7f1876d 100644
--- a/src-tauri/src/config.rs
+++ b/src-tauri/src/config.rs
@@ -138,10 +138,13 @@ impl UserConfig {
         supply
     }
 
-    pub fn flexibility_map(&self) -> HashMap<ResidentId, u8> {
+    pub fn flexibility_map(&self, from: Day) -> HashMap<ResidentId, u16> {
         let mut map = HashMap::new();
         for r in &self.residents {
-            map.insert(r.id, r.allowed_types.len() as u8);
+            let count = (from.0..=self.total_days)
+                .map(|d| r.available_slots_on(Day(d)))
+                .sum();
+            map.insert(r.id, count);
         }
         map
     }
diff --git a/src-tauri/src/resident.rs b/src-tauri/src/resident.rs
index 0258c94..9896b21 100644
--- a/src-tauri/src/resident.rs
+++ b/src-tauri/src/resident.rs
@@ -64,6 +64,16 @@ impl Resident {
         self
     }
 
+    pub fn available_slots_on(&self, day: Day) -> u16 {
+        if self.negative_shifts.contains(&day) {
+            return 0;
+        }
+        day.shift_types()
+            .iter()
+            .filter(|t| self.allowed_types.contains(t))
+            .count() as u16
+    }
+
     pub fn with_negative_shifts(mut self, negative_shifts: Vec<Day>) -> Self {
         self.negative_shifts = negative_shifts;
         self
diff --git a/src-tauri/src/scheduler.rs b/src-tauri/src/scheduler.rs
index d1ce3f2..8e4db58 100644
--- a/src-tauri/src/scheduler.rs
+++ b/src-tauri/src/scheduler.rs
@@ -200,7 +200,7 @@ impl Scheduler {
         tracker: &WorkloadTracker,
         slot: Slot,
     ) {
-        let flex_map = self.config.flexibility_map();
+        let flex_map = self.config.flexibility_map(slot.day);
         let mut rng = SmallRng::from_rng(&mut rand::rng());
         resident_ids.shuffle(&mut rng);
         resident_ids.sort_by_key(|r_id| {
diff --git a/src-tauri/src/slot.rs b/src-tauri/src/slot.rs
index b4b3a32..c347aee 100644
--- a/src-tauri/src/slot.rs
+++ b/src-tauri/src/slot.rs
@@ -136,6 +136,14 @@ impl Day {
         !self.0.is_multiple_of(2)
     }
 
+    pub fn shift_types(&self) -> &[ShiftType] {
+        if self.is_open_shift() {
+            &[ShiftType::OpenFirst, ShiftType::OpenSecond]
+        } else {
+            &[ShiftType::Closed]
+        }
+    }
+
     pub fn next(&self) -> Self {
         Self(self.0 + 1)
     }