diff --git a/justfile b/justfile
index 001e3c5..8af4c07 100644
--- a/justfile
+++ b/justfile
@@ -14,13 +14,13 @@ lint:
     cd {{tauri_path}} && cargo clippy
 
 test:
-    cd {{tauri_path}} && cargo test --lib --release
+    cd {{tauri_path}} && cargo test --lib -- --test-threads=1
 
 test-integration:
-    cd {{tauri_path}} && cargo test --test integration --release
+    cd {{tauri_path}} && cargo test --test integration -- --test-threads=1 --nocapture
 
 test-all:
-    cd {{tauri_path}} && cargo test --release -- --nocapture
+    cd {{tauri_path}} && cargo test --release
 
 bench:
     cd {{tauri_path}} && cargo bench
diff --git a/src-tauri/.gitignore b/src-tauri/.gitignore
index e05b79b..640ca96 100644
--- a/src-tauri/.gitignore
+++ b/src-tauri/.gitignore
@@ -7,4 +7,6 @@
 /gen/schemas
 
 # Ignore exported txt/doc files and the log file
-rota.*
\ No newline at end of file
+rota.*
+
+mutants.*
\ No newline at end of file
diff --git a/src-tauri/Cargo.lock b/src-tauri/Cargo.lock
index 5ff1737..cbbb103 100644
--- a/src-tauri/Cargo.lock
+++ b/src-tauri/Cargo.lock
@@ -65,7 +65,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dbb4e440d04be07da1f1bf44fb4495ebd58669372fe0cffa6e48595ac5bd88a3"
 dependencies = [
  "android_log-sys",
- "env_filter",
+ "env_filter 0.1.4",
  "log",
 ]
 
@@ -84,12 +84,56 @@ version = "0.1.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4b46cbb362ab8752921c97e041f5e366ee6297bd428a31275b9fcf1e380f7299"
 
+[[package]]
+name = "anstream"
+version = "0.6.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "43d5b281e737544384e969a5ccad3f1cdd24b48086a0fc1b2a5262a26b8f4f4a"
+dependencies = [
+ "anstyle",
+ "anstyle-parse",
+ "anstyle-query",
+ "anstyle-wincon",
+ "colorchoice",
+ "is_terminal_polyfill",
+ "utf8parse",
+]
+
 [[package]]
 name = "anstyle"
 version = "1.0.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5192cca8006f1fd4f7237516f40fa183bb07f8fbdfedaa0036de5ea9b0b45e78"
 
+[[package]]
+name = "anstyle-parse"
+version = "0.2.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4e7644824f0aa2c7b9384579234ef10eb7efb6a0deb83f9630a49594dd9c15c2"
+dependencies = [
+ "utf8parse",
+]
+
+[[package]]
+name = "anstyle-query"
+version = "1.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "40c48f72fd53cd289104fc64099abca73db4166ad86ea0b4341abe65af83dadc"
+dependencies = [
+ "windows-sys 0.61.2",
+]
+
+[[package]]
+name = "anstyle-wincon"
+version = "3.0.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "291e6a250ff86cd4a820112fb8898808a366d8f9f58ce16d1f538353ad55747d"
+dependencies = [
+ "anstyle",
+ "once_cell_polyfill",
+ "windows-sys 0.61.2",
+]
+
 [[package]]
 name = "anyhow"
 version = "1.0.100"
@@ -637,6 +681,12 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3d7b894f5411737b7867f4827955924d7c254fc9f4d91a6aad6b097804b1018b"
 
+[[package]]
+name = "colorchoice"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b05b61dc5112cbb17e4b6cd61790d9845d13888356391624cbe7e41efeac1e75"
+
 [[package]]
 name = "combine"
 version = "4.6.7"
@@ -742,7 +792,7 @@ dependencies = [
  "ciborium",
  "clap",
  "criterion-plot",
- "itertools 0.13.0",
+ "itertools",
  "num-traits",
  "oorandom",
  "page_size",
@@ -762,7 +812,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ed943f81ea2faa8dcecbbfa50164acf95d555afec96a27871663b300e387b2e4"
 dependencies = [
  "cast",
- "itertools 0.13.0",
+ "itertools",
 ]
 
 [[package]]
@@ -852,6 +902,22 @@ dependencies = [
  "syn 2.0.111",
 ]
 
+[[package]]
+name = "ctor"
+version = "0.6.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "424e0138278faeb2b401f174ad17e715c829512d74f3d1e81eb43365c2e0590e"
+dependencies = [
+ "ctor-proc-macro",
+ "dtor",
+]
+
+[[package]]
+name = "ctor-proc-macro"
+version = "0.0.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "52560adf09603e58c9a7ee1fe1dcb95a16927b17c127f0ac02d6e768a0e25bc1"
+
 [[package]]
 name = "darling"
 version = "0.21.3"
@@ -1030,6 +1096,21 @@ dependencies = [
  "dtoa",
 ]
 
+[[package]]
+name = "dtor"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "404d02eeb088a82cfd873006cb713fe411306c7d182c344905e101fb1167d301"
+dependencies = [
+ "dtor-proc-macro",
+]
+
+[[package]]
+name = "dtor-proc-macro"
+version = "0.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f678cf4a922c215c63e0de95eb1ff08a958a81d47e485cf9da1e27bf6305cfa5"
+
 [[package]]
 name = "dunce"
 version = "1.0.5"
@@ -1105,6 +1186,29 @@ dependencies = [
  "regex",
 ]
 
+[[package]]
+name = "env_filter"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7a1c3cc8e57274ec99de65301228b537f1e4eedc1b8e0f9411c6caac8ae7308f"
+dependencies = [
+ "log",
+ "regex",
+]
+
+[[package]]
+name = "env_logger"
+version = "0.11.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2daee4ea451f429a58296525ddf28b45a3b64f1acf6587e2067437bb11e218d"
+dependencies = [
+ "anstream",
+ "anstyle",
+ "env_filter 1.0.0",
+ "jiff",
+ "log",
+]
+
 [[package]]
 name = "equivalent"
 version = "1.0.2"
@@ -2033,6 +2137,12 @@ dependencies = [
  "once_cell",
 ]
 
+[[package]]
+name = "is_terminal_polyfill"
+version = "1.70.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a6cb138bb79a146c1bd460005623e142ef0181e3d0219cb493e02f7d08a35695"
+
 [[package]]
 name = "itertools"
 version = "0.13.0"
@@ -2042,15 +2152,6 @@ dependencies = [
  "either",
 ]
 
-[[package]]
-name = "itertools"
-version = "0.14.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2b192c782037fadd9cfa75548310488aabdbf3d2da73885b31bd0abd03351285"
-dependencies = [
- "either",
-]
-
 [[package]]
 name = "itoa"
 version = "1.0.15"
@@ -2080,6 +2181,30 @@ dependencies = [
  "system-deps",
 ]
 
+[[package]]
+name = "jiff"
+version = "0.2.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c867c356cc096b33f4981825ab281ecba3db0acefe60329f044c1789d94c6543"
+dependencies = [
+ "jiff-static",
+ "log",
+ "portable-atomic",
+ "portable-atomic-util",
+ "serde_core",
+]
+
+[[package]]
+name = "jiff-static"
+version = "0.2.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f7946b4325269738f270bb55b3c19ab5c5040525f83fd625259422a9d25d9be5"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.111",
+]
+
 [[package]]
 name = "jni"
 version = "0.21.1"
@@ -2668,6 +2793,12 @@ version = "1.21.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "42f5e15c9953c5e4ccceeb2e7382a716482c34515315f7b03532b8b4e8393d2d"
 
+[[package]]
+name = "once_cell_polyfill"
+version = "1.70.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "384b8ab6d37215f3c5301a95a4accb5d64aa607f1fcb26a11b5303878451b4fe"
+
 [[package]]
 name = "oorandom"
 version = "11.1.5"
@@ -3009,6 +3140,21 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
+[[package]]
+name = "portable-atomic"
+version = "1.13.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c33a9471896f1c69cecef8d20cbe2f7accd12527ce60845ff44c153bb2a21b49"
+
+[[package]]
+name = "portable-atomic-util"
+version = "0.2.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7a9db96d7fa8782dd8c15ce32ffe8680bbd1e978a43bf51a34d39483540495f5"
+dependencies = [
+ "portable-atomic",
+]
+
 [[package]]
 name = "potential_utf"
 version = "0.1.4"
@@ -3448,8 +3594,9 @@ dependencies = [
  "anyhow",
  "chrono",
  "criterion",
+ "ctor 0.6.3",
  "docx-rs",
- "itertools 0.14.0",
+ "env_logger",
  "log",
  "rand 0.9.2",
  "rayon",
@@ -4340,7 +4487,7 @@ dependencies = [
  "anyhow",
  "brotli",
  "cargo_metadata",
- "ctor",
+ "ctor 0.2.9",
  "dunce",
  "glob",
  "html5ever",
@@ -4868,6 +5015,12 @@ version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b6c140620e7ffbb22c2dee59cafe6084a59b5ffc27a8859a5f0d494b5d52b6be"
 
+[[package]]
+name = "utf8parse"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "06abde3611657adf66d383f00b093d7faecc7fa57071cce2578660c9f1010821"
+
 [[package]]
 name = "uuid"
 version = "1.19.0"
diff --git a/src-tauri/Cargo.toml b/src-tauri/Cargo.toml
index 60a6db1..3250d60 100644
--- a/src-tauri/Cargo.toml
+++ b/src-tauri/Cargo.toml
@@ -23,7 +23,6 @@ tauri-plugin-opener = "2"
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 chrono = "0.4.42"
-itertools = "0.14.0"
 rstest = "0.26.1"
 tauri-plugin-log = "2"
 log = "0.4.29"
@@ -35,6 +34,8 @@ thiserror = "2.0.18"
 
 [dev-dependencies]
 criterion = { version = "0.8.1", features = ["html_reports"] }
+env_logger = "0.11"
+ctor = "0.6.3"
 
 [[bench]]
 name = "rayon"
diff --git a/src-tauri/src/config.rs b/src-tauri/src/config.rs
index 471f747..36d3b7a 100644
--- a/src-tauri/src/config.rs
+++ b/src-tauri/src/config.rs
@@ -1,13 +1,16 @@
+use std::collections::HashMap;
+
 use anyhow::Context;
 use chrono::Month;
 use serde::{Deserialize, Serialize};
 
 use crate::{
     resident::{Resident, ResidentDTO, ResidentId},
+    schedule::ShiftType,
     slot::Day,
 };
 
-const MONTH: u8 = 2;
+const MONTH: u8 = 4;
 const YEAR: i32 = 2026;
 
 #[derive(Debug, Clone)]
@@ -87,6 +90,21 @@ impl UserConfig {
         day.is_weekend(self.month.number_from_month(), self.year)
             || self.holidays.contains(&(day.0))
     }
+
+    pub fn get_initial_supply(&self) -> HashMap<ShiftType, u8> {
+        let mut supply = HashMap::new();
+        let total_days = self.total_days;
+
+        for d in 1..=total_days {
+            if Day(d).is_open_shift() {
+                *supply.entry(ShiftType::OpenFirst).or_insert(0) += 1;
+                *supply.entry(ShiftType::OpenSecond).or_insert(0) += 1;
+            } else {
+                *supply.entry(ShiftType::Closed).or_insert(0) += 1;
+            }
+        }
+        supply
+    }
 }
 
 impl Default for UserConfig {
@@ -153,3 +171,18 @@ impl TryFrom<UserConfigDTO> for UserConfig {
         })
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use crate::{config::UserConfig, fixtures::complex_config, schedule::ShiftType};
+    use rstest::rstest;
+
+    #[rstest]
+    fn test_get_initial_supply(complex_config: UserConfig) {
+        let supply = complex_config.get_initial_supply();
+
+        assert_eq!(15, *supply.get(&ShiftType::OpenFirst).unwrap());
+        assert_eq!(15, *supply.get(&ShiftType::OpenSecond).unwrap());
+        assert_eq!(15, *supply.get(&ShiftType::Closed).unwrap());
+    }
+}
diff --git a/src-tauri/src/errors.rs b/src-tauri/src/errors.rs
index 782e2b9..cb64e94 100644
--- a/src-tauri/src/errors.rs
+++ b/src-tauri/src/errors.rs
@@ -1,5 +1,6 @@
 use std::io;
 
+use log::Level;
 use serde::Serialize;
 use thiserror::Error;
 
@@ -18,6 +19,16 @@ pub enum SearchError {
     NoSolutionFound,
 }
 
+impl SearchError {
+    pub fn log_level(&self) -> Level {
+        match self {
+            SearchError::SolutionFound | SearchError::ScheduleFull => Level::Info,
+            SearchError::NoSolutionFound => Level::Warn,
+            SearchError::Timeout | SearchError::Config(_) => Level::Error,
+        }
+    }
+}
+
 impl From<anyhow::Error> for SearchError {
     fn from(err: anyhow::Error) -> Self {
         SearchError::Config(err.to_string())
diff --git a/src-tauri/src/export.rs b/src-tauri/src/export.rs
index d83cf07..38c60e7 100644
--- a/src-tauri/src/export.rs
+++ b/src-tauri/src/export.rs
@@ -194,12 +194,12 @@ mod tests {
     #[fixture]
     fn config() -> UserConfig {
         UserConfig::default().with_residents(vec![
-            Resident::new(1, "Στέφανος"),
-            Resident::new(2, "Ιορδάνης"),
-            Resident::new(3, "Μαρία"),
-            Resident::new(4, "Βεατρίκη"),
-            Resident::new(5, "Τάκης"),
-            Resident::new(6, "Μάκης"),
+            Resident::new(1, "R1"),
+            Resident::new(2, "R2"),
+            Resident::new(3, "R3"),
+            Resident::new(4, "R4"),
+            Resident::new(5, "R5"),
+            Resident::new(6, "R6"),
         ])
     }
 
diff --git a/src-tauri/src/fixtures.rs b/src-tauri/src/fixtures.rs
new file mode 100644
index 0000000..e27d79d
--- /dev/null
+++ b/src-tauri/src/fixtures.rs
@@ -0,0 +1,177 @@
+use crate::{
+    config::{ToxicPair, UserConfig},
+    resident::Resident,
+    schedule::ShiftType,
+    slot::{Day, ShiftPosition, Slot},
+};
+
+use rstest::fixture;
+
+#[fixture]
+pub fn minimal_config() -> UserConfig {
+    UserConfig::default().with_residents(vec![
+        Resident::new(1, "R1"),
+        Resident::new(2, "R2"),
+        Resident::new(3, "R3"),
+        Resident::new(4, "R4"),
+        Resident::new(5, "R5"),
+    ])
+}
+
+#[fixture]
+pub fn maximal_config() -> UserConfig {
+    UserConfig::default()
+        .with_holidays(vec![2, 3, 10, 11, 12, 25])
+        .with_residents(vec![
+            Resident::new(1, "R1").with_max_shifts(3),
+            Resident::new(2, "R2").with_max_shifts(4),
+            Resident::new(3, "R3").with_reduced_load(),
+            Resident::new(4, "R4").with_allowed_types(vec![ShiftType::Closed]),
+            Resident::new(5, "R5")
+                .with_allowed_types(vec![ShiftType::OpenFirst, ShiftType::OpenSecond]),
+            Resident::new(6, "R6").with_negative_shifts(vec![Day(5), Day(15), Day(25)]),
+            Resident::new(7, "R7"),
+            Resident::new(8, "R8"),
+            Resident::new(9, "R9"),
+            Resident::new(10, "R10"),
+        ])
+        .with_toxic_pairs(vec![
+            ToxicPair::new(1, 2),
+            ToxicPair::new(3, 4),
+            ToxicPair::new(7, 8),
+        ])
+}
+
+#[fixture]
+pub fn manual_shifts_heavy_config() -> UserConfig {
+    UserConfig::default().with_residents(vec![
+        Resident::new(1, "R1").with_manual_shifts(vec![
+            Slot::new(Day(1), ShiftPosition::First),
+            Slot::new(Day(3), ShiftPosition::First),
+            Slot::new(Day(5), ShiftPosition::Second),
+        ]),
+        Resident::new(2, "R2").with_manual_shifts(vec![
+            Slot::new(Day(2), ShiftPosition::First),
+            Slot::new(Day(4), ShiftPosition::First),
+        ]),
+        Resident::new(3, "R3"),
+        Resident::new(4, "R4"),
+        Resident::new(5, "R5"),
+        Resident::new(6, "R6"),
+    ])
+}
+
+#[fixture]
+pub fn complex_config() -> UserConfig {
+    UserConfig::default()
+        .with_holidays(vec![5, 12, 19, 26])
+        .with_residents(vec![
+            Resident::new(1, "R1")
+                .with_max_shifts(3)
+                .with_negative_shifts(vec![Day(1), Day(2), Day(3)]),
+            Resident::new(2, "R2")
+                .with_max_shifts(3)
+                .with_negative_shifts(vec![Day(4), Day(5), Day(6)]),
+            Resident::new(3, "R3")
+                .with_max_shifts(3)
+                .with_negative_shifts(vec![Day(7), Day(8), Day(9)]),
+            Resident::new(4, "R4").with_allowed_types(vec![ShiftType::Closed]),
+            Resident::new(5, "R5")
+                .with_allowed_types(vec![ShiftType::OpenFirst, ShiftType::OpenSecond]),
+            Resident::new(6, "R6"),
+            Resident::new(7, "R7"),
+            Resident::new(8, "R8"),
+            Resident::new(9, "R9"),
+        ])
+        .with_toxic_pairs(vec![
+            ToxicPair::new(1, 2),
+            ToxicPair::new(2, 3),
+            ToxicPair::new(5, 6),
+            ToxicPair::new(6, 7),
+        ])
+}
+
+#[fixture]
+pub fn hard_config() -> UserConfig {
+    UserConfig::default()
+        .with_holidays(vec![25])
+        .with_residents(vec![
+            Resident::new(1, "R1")
+                .with_negative_shifts(vec![
+                    Day(2),
+                    Day(3),
+                    Day(4),
+                    Day(5),
+                    Day(6),
+                    Day(7),
+                    Day(8),
+                    Day(9),
+                    Day(13),
+                    Day(14),
+                    Day(15),
+                ])
+                .with_manual_shifts(vec![
+                    Slot::new(Day(1), ShiftPosition::First),
+                    Slot::new(Day(12), ShiftPosition::First),
+                ])
+                .with_max_shifts(6),
+            Resident::new(2, "R2")
+                .with_negative_shifts(vec![
+                    Day(2),
+                    Day(3),
+                    Day(4),
+                    Day(5),
+                    Day(6),
+                    Day(7),
+                    Day(8),
+                    Day(9),
+                ])
+                .with_manual_shifts(vec![Slot::new(Day(1), ShiftPosition::Second)]),
+            Resident::new(3, "R3").with_negative_shifts(vec![
+                Day(12),
+                Day(13),
+                Day(14),
+                Day(15),
+                Day(16),
+            ]),
+            Resident::new(4, "R4").with_negative_shifts(vec![Day(14), Day(15)]),
+            Resident::new(5, "R5")
+                .with_manual_shifts(vec![
+                    Slot::new(Day(2), ShiftPosition::First),
+                    Slot::new(Day(4), ShiftPosition::First),
+                    Slot::new(Day(7), ShiftPosition::First),
+                    Slot::new(Day(9), ShiftPosition::First),
+                ])
+                .with_negative_shifts(vec![
+                    Day(12),
+                    Day(13),
+                    Day(14),
+                    Day(15),
+                    Day(16),
+                    Day(17),
+                    Day(18),
+                    Day(19),
+                    Day(20),
+                    Day(21),
+                    Day(22),
+                    Day(23),
+                    Day(24),
+                    Day(25),
+                ]),
+            Resident::new(6, "R6")
+                .with_allowed_types(vec![ShiftType::OpenSecond])
+                .with_max_shifts(5),
+            Resident::new(7, "R7")
+                .with_max_shifts(5)
+                .with_negative_shifts(vec![Day(30), Day(31)]),
+            Resident::new(8, "R8")
+                .with_allowed_types(vec![ShiftType::OpenSecond])
+                .with_max_shifts(5),
+        ])
+        .with_toxic_pairs(vec![
+            ToxicPair::new(3, 6),
+            ToxicPair::new(3, 8),
+            ToxicPair::new(3, 7),
+            ToxicPair::new(3, 1),
+        ])
+}
diff --git a/src-tauri/src/lib.rs b/src-tauri/src/lib.rs
index 1faa4fb..58335dc 100644
--- a/src-tauri/src/lib.rs
+++ b/src-tauri/src/lib.rs
@@ -14,6 +14,7 @@ use crate::{
 pub mod config;
 pub mod errors;
 pub mod export;
+pub mod fixtures;
 pub mod resident;
 pub mod schedule;
 pub mod scheduler;
@@ -106,8 +107,20 @@ pub fn run() {
 
 #[cfg(test)]
 mod tests {
+
+    use ctor::ctor;
     use rstest::rstest;
 
+    #[ctor]
+    fn global_setup() {
+        env_logger::builder()
+            .filter_level(log::LevelFilter::Info)
+            .is_test(true)
+            .try_init();
+    }
+
     #[rstest]
-    pub fn test_endpoints() {}
+    pub fn test_endpoints() {
+        // see how tauri mocks endpoint tests
+    }
 }
diff --git a/src-tauri/src/schedule.rs b/src-tauri/src/schedule.rs
index b750ab9..fe37b87 100644
--- a/src-tauri/src/schedule.rs
+++ b/src-tauri/src/schedule.rs
@@ -5,7 +5,7 @@ use crate::{
     config::{ToxicPair, UserConfig},
     resident::ResidentId,
     slot::{weekday_to_greek, Day, ShiftPosition, Slot},
-    workload::{WorkloadBounds, WorkloadTracker},
+    workload::WorkloadTracker,
 };
 
 use serde::Serializer;
@@ -32,8 +32,8 @@ impl MonthlySchedule {
         self.0.get(slot)
     }
 
-    pub fn insert(&mut self, slot: Slot, resident_id: ResidentId) {
-        self.0.insert(slot, resident_id);
+    pub fn insert(&mut self, slot: Slot, r_id: ResidentId) {
+        self.0.insert(slot, r_id);
     }
 
     pub fn remove(&mut self, slot: Slot) {
@@ -44,32 +44,6 @@ impl MonthlySchedule {
         self.0.contains_key(slot)
     }
 
-    /// if any restriction is violated => we return true (leading to pruning in the backtracking algorithm)
-    /// 1) no same person in consecutive days
-    /// 2) avoid input toxic pairs
-    /// 3) apply fairness on total shifts split residents also take into account reduced (-1) workload
-    ///
-    /// @slot points to an occupied slot
-    /// @config info manually set on the GUI by the user
-    pub fn restrictions_violated(
-        &self,
-        slot: &Slot,
-        config: &UserConfig,
-        bounds: &WorkloadBounds,
-        tracker: &WorkloadTracker,
-    ) -> bool {
-        let resident_id = match self.get_resident_id(slot) {
-            Some(id) => id,
-            None => return false,
-        };
-
-        self.has_resident_in_consecutive_days(slot)
-            || self.has_toxic_pair(slot, config)
-            || tracker.is_total_workload_exceeded(bounds, resident_id)
-            || tracker.is_holiday_workload_exceeded(bounds, resident_id)
-            || tracker.is_max_shift_type_exceeded(bounds, resident_id, slot)
-    }
-
     pub fn has_resident_in_consecutive_days(&self, slot: &Slot) -> bool {
         if slot.day == Day(1) {
             return false;
@@ -89,9 +63,20 @@ impl MonthlySchedule {
             .any(|s| self.get_resident_id(s) == self.get_resident_id(slot))
     }
 
+    pub fn resident_worked_on_day(&self, day: Day, res_id: ResidentId) -> bool {
+        if day.0 < 1 {
+            return false;
+        }
+
+        let first = Slot::new(day, ShiftPosition::First);
+        let second = Slot::new(day, ShiftPosition::Second);
+
+        self.get_resident_id(&first) == Some(&res_id)
+            || self.get_resident_id(&second) == Some(&res_id)
+    }
+
     pub fn has_toxic_pair(&self, slot: &Slot, config: &UserConfig) -> bool {
-        // can only have caused a toxic pair violation if we just added a 2nd resident in an open shift
-        if !slot.is_open_second() {
+        if !slot.is_open_shift() {
             return false;
         }
 
@@ -113,11 +98,11 @@ impl MonthlySchedule {
         sorted.sort_by_key(|(slot, _)| (slot.day, slot.position));
 
         let mut output = String::from("Μηνιαίο Πρόγραμμα Εφημεριών\n");
-        for (slot, res_id) in sorted {
+        for (slot, r_id) in sorted {
             let res_name = config
                 .residents
                 .iter()
-                .find(|r| &r.id == res_id)
+                .find(|r| &r.id == r_id)
                 .map(|r| r.name.as_str())
                 .unwrap_or("");
 
@@ -137,7 +122,7 @@ impl MonthlySchedule {
 
     pub fn report(&self, config: &UserConfig, tracker: &WorkloadTracker) -> String {
         let mut output = String::new();
-        output.push_str("\n--- Αναφορά ---\n");
+        output.push('\n');
         output.push_str(&format!(
             "{:<15} | {:<6} | {:<10} | {:<10} | {:<7} | {:<10}\n",
             "Ειδικευόμενος", "Σύνολο", "Ανοιχτή(1)", "Ανοιχτή(2)", "Κλειστή", "ΣΚ/Αργίες"
@@ -148,16 +133,16 @@ impl MonthlySchedule {
         let mut residents: Vec<_> = config.residents.iter().collect();
         residents.sort_by_key(|r| &r.name);
 
-        for res in residents {
-            let total = tracker.current_workload(&res.id);
-            let o1 = tracker.get_type_count(&res.id, ShiftType::OpenFirst);
-            let o2 = tracker.get_type_count(&res.id, ShiftType::OpenSecond);
-            let cl = tracker.get_type_count(&res.id, ShiftType::Closed);
-            let holiday = tracker.current_holiday_workload(&res.id);
+        for r in residents {
+            let total = tracker.current_workload(&r.id);
+            let o1 = tracker.get_type_count(&r.id, ShiftType::OpenFirst);
+            let o2 = tracker.get_type_count(&r.id, ShiftType::OpenSecond);
+            let cl = tracker.get_type_count(&r.id, ShiftType::Closed);
+            let holiday = tracker.current_holiday_workload(&r.id);
 
             output.push_str(&format!(
                 "{:<15} | {:<6} | {:<10} | {:<10} | {:<7} | {:<10}\n",
-                res.name, total, o1, o2, cl, holiday
+                r.name, total, o1, o2, cl, holiday
             ));
         }
         output.push_str("-".repeat(85).as_str());
@@ -209,25 +194,19 @@ mod tests {
 
     #[fixture]
     fn resident() -> Resident {
-        Resident::new(1, "Stefanos")
+        Resident::new(1, "R1")
     }
 
     #[fixture]
     fn toxic_config() -> UserConfig {
         UserConfig::default()
-            .with_residents(vec![
-                Resident::new(1, "Stefanos"),
-                Resident::new(2, "Iordanis"),
-            ])
+            .with_residents(vec![Resident::new(1, "R1"), Resident::new(2, "R2")])
             .with_toxic_pairs(vec![ToxicPair::new(1, 2)])
     }
 
     #[fixture]
     fn config() -> UserConfig {
-        UserConfig::default().with_residents(vec![
-            Resident::new(1, "Stefanos"),
-            Resident::new(2, "Iordanis"),
-        ])
+        UserConfig::default().with_residents(vec![Resident::new(1, "R1"), Resident::new(2, "R2")])
     }
 
     #[rstest]
@@ -271,11 +250,11 @@ mod tests {
         let slot_1 = Slot::new(Day(1), ShiftPosition::First);
         let slot_2 = Slot::new(Day(1), ShiftPosition::Second);
 
-        let stefanos = &toxic_config.residents[0];
-        let iordanis = &toxic_config.residents[1];
+        let r1 = &toxic_config.residents[0];
+        let r2 = &toxic_config.residents[1];
 
-        schedule.insert(slot_1, stefanos.id);
-        schedule.insert(slot_2, iordanis.id);
+        schedule.insert(slot_1, r1.id);
+        schedule.insert(slot_2, r2.id);
 
         assert!(schedule.has_toxic_pair(&slot_2, &toxic_config))
     }
diff --git a/src-tauri/src/scheduler.rs b/src-tauri/src/scheduler.rs
index 69b2303..2be90c0 100644
--- a/src-tauri/src/scheduler.rs
+++ b/src-tauri/src/scheduler.rs
@@ -1,7 +1,7 @@
 use std::sync::atomic::{AtomicBool, Ordering};
 
 use crate::{
-    config::UserConfig,
+    config::{ToxicPair, UserConfig},
     errors::SearchError,
     resident::ResidentId,
     schedule::MonthlySchedule,
@@ -10,7 +10,6 @@ use crate::{
     workload::{WorkloadBounds, WorkloadTracker},
 };
 
-use log::info;
 use rand::{rngs::SmallRng, seq::SliceRandom, SeedableRng};
 use rayon::{
     current_thread_index,
@@ -60,7 +59,7 @@ impl Scheduler {
             .map(Slot::from)
             .ok_or(SearchError::ScheduleFull)?;
 
-        let resident_ids = self.valid_residents(slot, schedule);
+        let resident_ids = self.valid_residents(slot, schedule, tracker);
         let solved_in_thread = AtomicBool::new(false);
 
         let sovled_state = resident_ids.par_iter().find_map_any(|&id| {
@@ -81,7 +80,8 @@ impl Scheduler {
                 Ok(true) => Some((local_schedule, local_tracker)),
                 Ok(false) => None,
                 Err(e) => {
-                    info!("Thread Id: [{}] {}", current_thread_index().unwrap(), e);
+                    let thread_id = current_thread_index().unwrap();
+                    log::log!(e.log_level(), "Thread Id: [{}] {}", thread_id, e);
                     None
                 }
             }
@@ -114,18 +114,13 @@ impl Scheduler {
             return Err(SearchError::Timeout);
         }
 
-        if !slot.is_first()
-            && schedule.restrictions_violated(&slot.previous(), &self.config, &self.bounds, tracker)
-        {
+        if schedule.has_resident_in_consecutive_days(&slot.previous()) {
             return Ok(false);
         }
 
-        if slot.greater_than(self.config.total_days) {
-            if tracker.are_all_thresholds_met(&self.config, &self.bounds) {
-                solved_in_thread.store(true, Ordering::Relaxed);
-                return Ok(true);
-            }
-            return Ok(false);
+        if self.found_solution(slot) {
+            solved_in_thread.store(true, Ordering::Relaxed);
+            return Ok(true);
         }
 
         if schedule.is_slot_manually_assigned(&slot) {
@@ -133,7 +128,7 @@ impl Scheduler {
         }
 
         let mut rng = SmallRng::from_rng(&mut rand::rng());
-        let mut valid_resident_ids = self.valid_residents(slot, schedule);
+        let mut valid_resident_ids = self.valid_residents(slot, schedule, tracker);
         valid_resident_ids.shuffle(&mut rng);
         valid_resident_ids.sort_by_key(|res_id| {
             let type_count = tracker.get_type_count(res_id, slot.shift_type());
@@ -156,10 +151,19 @@ impl Scheduler {
         Ok(false)
     }
 
+    pub fn found_solution(&self, slot: Slot) -> bool {
+        slot.greater_than(self.config.total_days)
+    }
+
     /// Return all valid residents for the current slot
-    pub fn valid_residents(&self, slot: Slot, schedule: &MonthlySchedule) -> Vec<ResidentId> {
-        let required_type = slot.shift_type();
-        let other_resident = slot
+    pub fn valid_residents(
+        &self,
+        slot: Slot,
+        schedule: &MonthlySchedule,
+        tracker: &WorkloadTracker,
+    ) -> Vec<ResidentId> {
+        let is_holiday_slot = self.config.is_holiday_or_weekend_slot(slot.day.0);
+        let other_resident_id = slot
             .other_position()
             .and_then(|partner_slot| schedule.get_resident_id(&partner_slot));
 
@@ -167,9 +171,26 @@ impl Scheduler {
             .residents
             .iter()
             .filter(|r| {
-                Some(&r.id) != other_resident
-                    && !r.negative_shifts.contains(&slot.day)
-                    && r.allowed_types.contains(&required_type)
+                if let Some(other_id) = other_resident_id {
+                    if &r.id == other_id {
+                        return false;
+                    }
+
+                    if self
+                        .config
+                        .toxic_pairs
+                        .iter()
+                        .any(|tp| tp.matches(&ToxicPair::from((r.id, *other_id))))
+                    {
+                        return false;
+                    }
+                }
+
+                !r.negative_shifts.contains(&slot.day)
+                    && r.allowed_types.contains(&slot.shift_type())
+                    && !tracker.reached_workload_limit(&self.bounds, &r.id)
+                    && (!is_holiday_slot || !tracker.reached_holiday_limit(&self.bounds, &r.id))
+                    && !tracker.reached_shift_type_limit(&self.bounds, &r.id, &slot)
             })
             .map(|r| r.id)
             .collect()
@@ -185,7 +206,6 @@ mod tests {
         resident::Resident,
         schedule::MonthlySchedule,
         scheduler::Scheduler,
-        slot::{Day, ShiftPosition, Slot},
         workload::{WorkloadBounds, WorkloadTracker},
     };
 
@@ -197,12 +217,12 @@ mod tests {
     #[fixture]
     fn config() -> UserConfig {
         UserConfig::default().with_residents(vec![
-            Resident::new(1, "Stefanos"),
-            Resident::new(2, "Iordanis"),
-            Resident::new(3, "Maria"),
-            Resident::new(4, "Veatriki"),
-            Resident::new(5, "Takis"),
-            Resident::new(6, "Akis"),
+            Resident::new(1, "R1"),
+            Resident::new(2, "R2"),
+            Resident::new(3, "R3"),
+            Resident::new(4, "R4"),
+            Resident::new(5, "R5"),
+            Resident::new(6, "R6"),
         ])
     }
 
@@ -227,25 +247,8 @@ mod tests {
         mut tracker: WorkloadTracker,
         scheduler: Scheduler,
     ) {
-        assert!(scheduler.run(&mut schedule, &mut tracker).is_ok());
-
-        for d in 1..=scheduler.config.total_days {
-            let day = Day(d);
-            if day.is_open_shift() {
-                let slot_first = Slot::new(day, ShiftPosition::First);
-                assert!(schedule.get_resident_id(&slot_first).is_some());
-                let slot_second = Slot::new(day, ShiftPosition::Second);
-                assert!(schedule.get_resident_id(&slot_second).is_some());
-            } else {
-                let slot_first = Slot::new(day, ShiftPosition::First);
-                assert!(schedule.get_resident_id(&slot_first).is_some());
-            }
-        }
-
-        for r in &scheduler.config.residents {
-            let workload = tracker.current_workload(&r.id);
-            let limit = *scheduler.bounds.max_workloads.get(&r.id).unwrap();
-            assert!(workload <= limit);
-        }
+        let solved = scheduler.run(&mut schedule, &mut tracker);
+        assert!(solved.is_ok());
+        assert!(solved.unwrap());
     }
 }
diff --git a/src-tauri/src/slot.rs b/src-tauri/src/slot.rs
index 1869452..4a347e9 100644
--- a/src-tauri/src/slot.rs
+++ b/src-tauri/src/slot.rs
@@ -45,7 +45,7 @@ impl Slot {
                 day: self.day,
                 position: ShiftPosition::Second,
             },
-            _ => Self {
+            ShiftPosition::First | ShiftPosition::Second => Self {
                 day: self.day.next(),
                 position: ShiftPosition::First,
             },
diff --git a/src-tauri/src/timer.rs b/src-tauri/src/timer.rs
index 3d3df45..c7af2ab 100644
--- a/src-tauri/src/timer.rs
+++ b/src-tauri/src/timer.rs
@@ -1,6 +1,6 @@
 use std::time::Instant;
 
-pub const TIME_LIMIT_IN_MS: u128 = 100000;
+pub const TIME_LIMIT_IN_MS: u128 = 5000; // 5 sec
 
 pub struct Timer {
     instant: Instant,
diff --git a/src-tauri/src/workload.rs b/src-tauri/src/workload.rs
index 346c5b0..4fde08a 100644
--- a/src-tauri/src/workload.rs
+++ b/src-tauri/src/workload.rs
@@ -2,9 +2,9 @@ use std::collections::HashMap;
 
 use crate::{
     config::UserConfig,
-    resident::ResidentId,
+    resident::{Resident, ResidentId},
     schedule::ShiftType,
-    slot::{Day, Slot},
+    slot::Slot,
 };
 
 #[derive(Default)]
@@ -12,175 +12,91 @@ pub struct WorkloadBounds {
     pub max_workloads: HashMap<ResidentId, u8>,
     pub max_holiday_shifts: HashMap<ResidentId, u8>,
     pub max_by_shift_type: HashMap<(ResidentId, ShiftType), u8>,
-    pub min_by_shift_type: HashMap<(ResidentId, ShiftType), u8>,
 }
 
 impl WorkloadBounds {
     pub fn new_with_config(config: &UserConfig) -> Self {
+        let residents = &config.residents;
+        let total_slots = config.total_slots;
+        let total_holiday_slots = config.total_holiday_slots;
+
         let mut bounds = Self::default();
-        bounds.calculate_max_workloads(config);
-        bounds.calculate_max_holiday_shifts(config);
-        bounds.calculate_max_by_shift_type(config);
+        bounds.calculate_max_workloads(residents, total_slots);
+        debug_assert!(bounds.max_workloads.values().sum::<u8>() >= total_slots);
+        bounds.calculate_max_holiday_shifts(residents, total_holiday_slots);
+        debug_assert!(bounds.max_holiday_shifts.values().sum::<u8>() >= total_holiday_slots);
+        bounds.calculate_max_by_shift_type(residents);
+        debug_assert!(bounds.max_by_shift_type.values().sum::<u8>() >= total_slots);
         bounds
     }
 
-    /// get map with total amount of slots in a month for each type of shift
-    pub fn get_initial_supply(&self, config: &UserConfig) -> HashMap<ShiftType, u8> {
-        let mut supply = HashMap::new();
-        let total_days = config.total_days;
-
-        for d in 1..=total_days {
-            if Day(d).is_open_shift() {
-                *supply.entry(ShiftType::OpenFirst).or_insert(0) += 1;
-                *supply.entry(ShiftType::OpenSecond).or_insert(0) += 1;
-            } else {
-                *supply.entry(ShiftType::Closed).or_insert(0) += 1;
-            }
-        }
-        supply
-    }
-
-    /// this is called after the user config params have been initialized, can be done with the builder (lite) pattern
-    /// initialize a hashmap for O(1) search calls for the residents' max workload
-    pub fn calculate_max_workloads(&mut self, config: &UserConfig) {
-        let auto_computed_residents: Vec<_> = config
-            .residents
+    pub fn calculate_max_workloads(&mut self, residents: &Vec<Resident>, total_slots: u8) {
+        let non_manual_residents: Vec<_> = residents
             .iter()
             .filter(|r| r.max_shifts.is_none())
             .collect();
 
-        // if all residents have a manually set max shifts size, just use those values for the max workload
-        if auto_computed_residents.is_empty() {
-            for r in &config.residents {
+        // all residents' max workload were manually inserted
+        if non_manual_residents.is_empty() {
+            for r in residents {
                 self.max_workloads.insert(r.id, r.max_shifts.unwrap_or(0));
             }
             return;
         }
 
-        // Untested scenario: Resident has manual max_shifts and also reduced workload flag
-        // Probably should forbid using both options from GUI
+        let total_manual_workload: u8 = residents.iter().map(|r| r.max_shifts.unwrap_or(0)).sum();
+        let remaining_slots = total_slots - total_manual_workload;
+        let workload_share = remaining_slots.div_ceil(non_manual_residents.len() as u8);
 
-        let manual_max_shifts_sum: u8 = config
-            .residents
-            .iter()
-            .map(|r| r.max_shifts.unwrap_or(0))
-            .sum();
-
-        let max_shifts_ceiling = ((config.total_slots - manual_max_shifts_sum) as f32
-            / auto_computed_residents.len() as f32)
-            .ceil() as u8;
-
-        for r in &config.residents {
-            let max_shifts = match r.max_shifts {
-                Some(shifts) => shifts,
-                None if r.reduced_load => max_shifts_ceiling - 1,
-                None => max_shifts_ceiling,
+        for r in residents {
+            let max_workload = match r.max_shifts {
+                Some(max_shifts) => max_shifts,
+                None if r.reduced_load => workload_share - 1,
+                None => workload_share,
             };
-            self.max_workloads.insert(r.id, max_shifts);
+            self.max_workloads.insert(r.id, max_workload);
         }
     }
 
-    pub fn calculate_max_holiday_shifts(&mut self, config: &UserConfig) {
-        let total_slots = config.total_slots;
-        let total_holiday_slots = config.total_holiday_slots;
-
-        for r in &config.residents {
-            let workload_limit = *self.max_workloads.get(&r.id).unwrap_or(&0);
-
-            let share = (workload_limit as f32 / total_slots as f32) * total_holiday_slots as f32;
-            let holiday_limit = share.ceil() as u8;
-
-            self.max_holiday_shifts.insert(r.id, holiday_limit);
+    pub fn calculate_max_holiday_shifts(
+        &mut self,
+        residents: &Vec<Resident>,
+        total_holiday_slots: u8,
+    ) {
+        let total_residents = residents.len();
+        let holiday_share = total_holiday_slots.div_ceil(total_residents as u8);
+        for r in residents {
+            self.max_holiday_shifts.insert(r.id, holiday_share);
         }
     }
 
-    pub fn calculate_max_by_shift_type(&mut self, config: &UserConfig) {
-        let mut supply_by_shift_type = self.get_initial_supply(config);
-        let mut local_limits = HashMap::new();
-        let mut local_thresholds = HashMap::new();
-
-        let all_shift_types = [
+    pub fn calculate_max_by_shift_type(&mut self, residents: &Vec<Resident>) {
+        let mut upper_limits = HashMap::new();
+        let shift_types = [
             ShiftType::OpenFirst,
             ShiftType::OpenSecond,
             ShiftType::Closed,
         ];
 
-        // residents with 1 available shift types
-        for res in config
-            .residents
-            .iter()
-            .filter(|r| r.allowed_types.len() == 1)
-        {
-            let shift_type = res.allowed_types[0];
-            let total_limit = *self.max_workloads.get(&res.id).unwrap_or(&0);
+        for r in residents {
+            let total_limit = *self.max_workloads.get(&r.id).unwrap_or(&0);
+            let n_allowed = r.allowed_types.len();
 
-            local_limits.insert((res.id, shift_type), total_limit);
-            local_thresholds.insert((res.id, shift_type), total_limit.saturating_sub(2));
-
-            for other_type in all_shift_types {
-                if other_type != shift_type {
-                    local_limits.insert((res.id, other_type), 0);
-                    local_thresholds.insert((res.id, other_type), 0);
-                }
-            }
-
-            if let Some(s) = supply_by_shift_type.get_mut(&shift_type) {
-                *s = s.saturating_sub(total_limit)
-            }
-        }
-
-        // residents with 2 available shift types
-        for res in config
-            .residents
-            .iter()
-            .filter(|r| r.allowed_types.len() == 2)
-        {
-            let total_limit = *self.max_workloads.get(&res.id).unwrap_or(&0);
-            let per_type = ((total_limit as f32) / 2.0).ceil() as u8;
-
-            let deduct_amount = (total_limit as f32 / 2.0) as u8;
-
-            for shift_type in all_shift_types {
-                if res.allowed_types.contains(&shift_type) {
-                    local_limits.insert((res.id, shift_type), per_type);
-                    local_thresholds.insert((res.id, shift_type), per_type.saturating_sub(2));
-                    if let Some(s) = supply_by_shift_type.get_mut(&shift_type) {
-                        *s = s.saturating_sub(deduct_amount);
+            for shift_type in shift_types {
+                let limit = if r.allowed_types.contains(&shift_type) {
+                    if n_allowed == 1 {
+                        total_limit
+                    } else {
+                        (total_limit as f32 / n_allowed as f32).floor() as u8 + 1
                     }
                 } else {
-                    local_limits.insert((res.id, shift_type), 0);
-                    local_thresholds.insert((res.id, shift_type), 0);
-                }
+                    0
+                };
+
+                upper_limits.insert((r.id, shift_type), limit);
             }
         }
-
-        // residents with 3 available shift types
-        for res in config
-            .residents
-            .iter()
-            .filter(|r| r.allowed_types.len() == 3)
-        {
-            let total_limit = *self.max_workloads.get(&res.id).unwrap_or(&0);
-            let per_type = ((total_limit as f32) / 3.0).ceil() as u8;
-
-            let deduct_amount = (total_limit as f32 / 3.0) as u8;
-
-            for shift_type in all_shift_types {
-                if res.allowed_types.contains(&shift_type) {
-                    local_limits.insert((res.id, shift_type), per_type);
-                    local_thresholds.insert((res.id, shift_type), per_type.saturating_sub(2));
-                    if let Some(s) = supply_by_shift_type.get_mut(&shift_type) {
-                        *s = s.saturating_sub(deduct_amount);
-                    }
-                } else {
-                    local_limits.insert((res.id, shift_type), 0);
-                    local_thresholds.insert((res.id, shift_type), 0);
-                }
-            }
-        }
-
-        self.max_by_shift_type = local_limits;
-        self.min_by_shift_type = local_thresholds;
+        self.max_by_shift_type = upper_limits;
     }
 }
 
@@ -192,71 +108,47 @@ pub struct WorkloadTracker {
 }
 
 impl WorkloadTracker {
-    pub fn insert(&mut self, res_id: ResidentId, config: &UserConfig, slot: Slot) {
-        *self.total_counts.entry(res_id).or_insert(0) += 1;
+    pub fn insert(&mut self, r_id: ResidentId, config: &UserConfig, slot: Slot) {
+        *self.total_counts.entry(r_id).or_insert(0) += 1;
         *self
             .type_counts
-            .entry((res_id, slot.shift_type()))
+            .entry((r_id, slot.shift_type()))
             .or_insert(0) += 1;
 
         if config.is_holiday_or_weekend_slot(slot.day.0) {
-            *self.holidays.entry(res_id).or_insert(0) += 1;
+            *self.holidays.entry(r_id).or_insert(0) += 1;
         }
     }
 
-    pub fn remove(&mut self, resident_id: ResidentId, config: &UserConfig, slot: Slot) {
-        if let Some(count) = self.total_counts.get_mut(&resident_id) {
+    pub fn remove(&mut self, r_id: ResidentId, config: &UserConfig, slot: Slot) {
+        if let Some(count) = self.total_counts.get_mut(&r_id) {
             *count = count.saturating_sub(1);
         }
 
-        if let Some(count) = self.type_counts.get_mut(&(resident_id, slot.shift_type())) {
+        if let Some(count) = self.type_counts.get_mut(&(r_id, slot.shift_type())) {
             *count = count.saturating_sub(1);
         }
 
         if config.is_holiday_or_weekend_slot(slot.day.0) {
-            if let Some(count) = self.holidays.get_mut(&resident_id) {
+            if let Some(count) = self.holidays.get_mut(&r_id) {
                 *count = count.saturating_sub(1);
             }
         }
     }
 
-    pub fn current_workload(&self, res_id: &ResidentId) -> u8 {
-        *self.total_counts.get(res_id).unwrap_or(&0)
+    pub fn current_workload(&self, r_id: &ResidentId) -> u8 {
+        *self.total_counts.get(r_id).unwrap_or(&0)
     }
 
-    pub fn current_holiday_workload(&self, resident_id: &ResidentId) -> u8 {
-        *self.holidays.get(resident_id).unwrap_or(&0)
+    pub fn current_holiday_workload(&self, r_id: &ResidentId) -> u8 {
+        *self.holidays.get(r_id).unwrap_or(&0)
     }
 
-    pub fn are_all_thresholds_met(&self, config: &UserConfig, bounds: &WorkloadBounds) -> bool {
-        const SHIFT_TYPES: [ShiftType; 3] = [
-            ShiftType::OpenFirst,
-            ShiftType::OpenSecond,
-            ShiftType::Closed,
-        ];
+    pub fn reached_workload_limit(&self, bounds: &WorkloadBounds, r_id: &ResidentId) -> bool {
+        let current_load = self.current_workload(r_id);
 
-        for r in &config.residents {
-            for shift_type in SHIFT_TYPES {
-                let current_load = self.type_counts.get(&(r.id, shift_type)).unwrap_or(&0);
-                if let Some(&min) = bounds.min_by_shift_type.get(&(r.id, shift_type)) {
-                    if *current_load < min {
-                        return false;
-                    }
-                }
-            }
-        }
-        true
-    }
-
-    pub fn is_total_workload_exceeded(
-        &self,
-        bounds: &WorkloadBounds,
-        resident_id: &ResidentId,
-    ) -> bool {
-        let current_load = self.current_workload(resident_id);
-
-        if let Some(&max) = bounds.max_workloads.get(resident_id) {
-            if current_load > max {
+        if let Some(&max) = bounds.max_workloads.get(r_id) {
+            if current_load >= max {
                 return true;
             }
         }
@@ -264,15 +156,11 @@ impl WorkloadTracker {
         false
     }
 
-    pub fn is_holiday_workload_exceeded(
-        &self,
-        bounds: &WorkloadBounds,
-        resident_id: &ResidentId,
-    ) -> bool {
-        let current_load = self.current_holiday_workload(resident_id);
+    pub fn reached_holiday_limit(&self, bounds: &WorkloadBounds, r_id: &ResidentId) -> bool {
+        let current_load = self.current_holiday_workload(r_id);
 
-        if let Some(&max) = bounds.max_holiday_shifts.get(resident_id) {
-            if current_load > max {
+        if let Some(&max) = bounds.max_holiday_shifts.get(r_id) {
+            if current_load >= max {
                 return true;
             }
         }
@@ -280,27 +168,24 @@ impl WorkloadTracker {
         false
     }
 
-    pub fn is_max_shift_type_exceeded(
+    pub fn reached_shift_type_limit(
         &self,
         bounds: &WorkloadBounds,
-        resident_id: &ResidentId,
+        r_id: &ResidentId,
         slot: &Slot,
     ) -> bool {
         let shift_type = slot.shift_type();
-        let current_load = self
-            .type_counts
-            .get(&(*resident_id, shift_type))
-            .unwrap_or(&0);
+        let current_load = self.type_counts.get(&(*r_id, shift_type)).unwrap_or(&0);
 
-        if let Some(&max) = bounds.max_by_shift_type.get(&(*resident_id, shift_type)) {
-            return *current_load > max;
+        if let Some(&max) = bounds.max_by_shift_type.get(&(*r_id, shift_type)) {
+            return *current_load >= max;
         }
 
         false
     }
 
-    pub fn get_type_count(&self, res_id: &ResidentId, shift_type: ShiftType) -> u8 {
-        *self.type_counts.get(&(*res_id, shift_type)).unwrap_or(&0)
+    pub fn get_type_count(&self, r_id: &ResidentId, shift_type: ShiftType) -> u8 {
+        *self.type_counts.get(&(*r_id, shift_type)).unwrap_or(&0)
     }
 }
 
@@ -308,7 +193,9 @@ impl WorkloadTracker {
 mod tests {
     use crate::{
         config::UserConfig,
+        fixtures::{complex_config, hard_config, minimal_config},
         resident::{Resident, ResidentId},
+        schedule::ShiftType,
         slot::{Day, ShiftPosition, Slot},
         workload::{WorkloadBounds, WorkloadTracker},
     };
@@ -317,11 +204,11 @@ mod tests {
     #[fixture]
     fn config() -> UserConfig {
         UserConfig::default().with_residents(vec![
-            Resident::new(1, "Stefanos").with_max_shifts(2),
-            Resident::new(2, "Iordanis").with_max_shifts(2),
-            Resident::new(3, "Maria").with_reduced_load(),
-            Resident::new(4, "Veatriki"),
-            Resident::new(5, "Takis"),
+            Resident::new(1, "R1").with_max_shifts(2),
+            Resident::new(2, "R2").with_max_shifts(2),
+            Resident::new(3, "R3").with_reduced_load(),
+            Resident::new(4, "R4"),
+            Resident::new(5, "R5"),
         ])
     }
 
@@ -333,53 +220,252 @@ mod tests {
     #[rstest]
     fn test_max_workloads(config: UserConfig) {
         let bounds = WorkloadBounds::new_with_config(&config);
-
-        assert_eq!(bounds.max_workloads[&ResidentId(1)], 2);
-        assert_eq!(bounds.max_workloads[&ResidentId(2)], 2);
-        assert!(bounds.max_workloads[&ResidentId(3)] > 0);
+        assert_eq!(2, bounds.max_workloads[&ResidentId(1)]);
+        assert_eq!(2, bounds.max_workloads[&ResidentId(2)]);
+        assert_eq!(13, bounds.max_workloads[&ResidentId(3)]);
+        assert_eq!(14, bounds.max_workloads[&ResidentId(4)]);
+        assert_eq!(14, bounds.max_workloads[&ResidentId(5)]);
     }
 
     #[rstest]
-    fn test_is_total_workload_exceeded(mut tracker: WorkloadTracker, config: UserConfig) {
-        let res_id = ResidentId(1);
+    fn test_reached_workload_limit(mut tracker: WorkloadTracker, config: UserConfig) {
+        let r_id = ResidentId(1);
         let mut bounds = WorkloadBounds::default();
-        bounds.max_workloads.insert(res_id, 1);
+        bounds.max_workloads.insert(r_id, 1);
 
         let slot_1 = Slot::new(Day(1), ShiftPosition::First);
         let slot_2 = Slot::new(Day(2), ShiftPosition::First);
 
-        tracker.insert(res_id, &config, slot_1);
-        assert!(!tracker.is_total_workload_exceeded(&bounds, &res_id,));
+        assert!(!tracker.reached_workload_limit(&bounds, &r_id,));
 
-        tracker.insert(res_id, &config, slot_2);
-        assert!(tracker.is_total_workload_exceeded(&bounds, &res_id,));
+        tracker.insert(r_id, &config, slot_1);
+        assert!(tracker.reached_workload_limit(&bounds, &r_id,));
+
+        tracker.insert(r_id, &config, slot_2);
+        assert!(tracker.reached_workload_limit(&bounds, &r_id,));
     }
 
     #[rstest]
-    fn test_is_holiday_workload_exceeded(mut tracker: WorkloadTracker, config: UserConfig) {
-        let res_id = ResidentId(1);
+    fn test_reached_holiday_limit(mut tracker: WorkloadTracker, config: UserConfig) {
+        let r_id = ResidentId(1);
         let mut bounds = WorkloadBounds::default();
-        bounds.max_holiday_shifts.insert(res_id, 1);
+        bounds.max_holiday_shifts.insert(r_id, 1);
 
-        let sat = Slot::new(Day(7), ShiftPosition::First);
-        let sun = Slot::new(Day(8), ShiftPosition::First);
+        let sat = Slot::new(Day(11), ShiftPosition::First);
+        let sun = Slot::new(Day(12), ShiftPosition::First);
 
-        tracker.insert(res_id, &config, sat);
-        assert!(!tracker.is_holiday_workload_exceeded(&bounds, &res_id));
+        assert!(!tracker.reached_holiday_limit(&bounds, &r_id));
 
-        tracker.insert(res_id, &config, sun);
-        assert!(tracker.is_holiday_workload_exceeded(&bounds, &res_id));
+        tracker.insert(r_id, &config, sat);
+        assert!(tracker.reached_holiday_limit(&bounds, &r_id));
+
+        tracker.insert(r_id, &config, sun);
+        assert!(tracker.reached_holiday_limit(&bounds, &r_id));
     }
 
     #[rstest]
     fn test_backtracking_accuracy(mut tracker: WorkloadTracker, config: UserConfig) {
-        let res_id = ResidentId(1);
+        let r_id = ResidentId(1);
         let slot = Slot::new(Day(1), ShiftPosition::First);
 
-        tracker.insert(res_id, &config, slot);
-        assert_eq!(tracker.current_workload(&res_id), 1);
+        tracker.insert(r_id, &config, slot);
+        assert_eq!(tracker.current_workload(&r_id), 1);
 
-        tracker.remove(res_id, &config, slot);
-        assert_eq!(tracker.current_workload(&res_id), 0);
+        tracker.remove(r_id, &config, slot);
+        assert_eq!(tracker.current_workload(&r_id), 0);
+    }
+
+    #[rstest]
+    fn test_calculate_max_workloads_minimal(minimal_config: UserConfig) {
+        let mut bounds = WorkloadBounds::default();
+        bounds.calculate_max_workloads(&minimal_config.residents, minimal_config.total_slots);
+
+        assert_eq!(9, *bounds.max_workloads.get(&ResidentId(1)).unwrap());
+        assert_eq!(9, *bounds.max_workloads.get(&ResidentId(2)).unwrap());
+        assert_eq!(9, *bounds.max_workloads.get(&ResidentId(3)).unwrap());
+        assert_eq!(9, *bounds.max_workloads.get(&ResidentId(4)).unwrap());
+        assert_eq!(9, *bounds.max_workloads.get(&ResidentId(5)).unwrap());
+    }
+
+    #[rstest]
+    fn test_calculate_max_workloads_complex(complex_config: UserConfig) {
+        let mut bounds = WorkloadBounds::default();
+        bounds.calculate_max_workloads(&complex_config.residents, complex_config.total_slots);
+
+        assert_eq!(3, *bounds.max_workloads.get(&ResidentId(1)).unwrap());
+        assert_eq!(3, *bounds.max_workloads.get(&ResidentId(2)).unwrap());
+        assert_eq!(3, *bounds.max_workloads.get(&ResidentId(3)).unwrap());
+
+        assert_eq!(6, *bounds.max_workloads.get(&ResidentId(4)).unwrap());
+        assert_eq!(6, *bounds.max_workloads.get(&ResidentId(5)).unwrap());
+        assert_eq!(6, *bounds.max_workloads.get(&ResidentId(6)).unwrap());
+        assert_eq!(6, *bounds.max_workloads.get(&ResidentId(7)).unwrap());
+        assert_eq!(6, *bounds.max_workloads.get(&ResidentId(8)).unwrap());
+        assert_eq!(6, *bounds.max_workloads.get(&ResidentId(9)).unwrap());
+    }
+
+    #[rstest]
+    fn test_calculate_max_workloads_hard(hard_config: UserConfig) {
+        let mut bounds = WorkloadBounds::default();
+        bounds.calculate_max_workloads(&hard_config.residents, hard_config.total_slots);
+
+        assert_eq!(5, *bounds.max_workloads.get(&ResidentId(6)).unwrap());
+        assert_eq!(5, *bounds.max_workloads.get(&ResidentId(7)).unwrap());
+        assert_eq!(5, *bounds.max_workloads.get(&ResidentId(8)).unwrap());
+
+        assert_eq!(6, *bounds.max_workloads.get(&ResidentId(1)).unwrap());
+        assert_eq!(6, *bounds.max_workloads.get(&ResidentId(2)).unwrap());
+        assert_eq!(6, *bounds.max_workloads.get(&ResidentId(3)).unwrap());
+        assert_eq!(6, *bounds.max_workloads.get(&ResidentId(4)).unwrap());
+        assert_eq!(6, *bounds.max_workloads.get(&ResidentId(5)).unwrap());
+    }
+
+    #[rstest]
+    fn test_calculate_max_holiday_shifts_complex(complex_config: UserConfig) {
+        let mut bounds = WorkloadBounds::default();
+        bounds.calculate_max_holiday_shifts(
+            &complex_config.residents,
+            complex_config.total_holiday_slots,
+        );
+
+        for i in 1..=9 {
+            assert_eq!(2, *bounds.max_holiday_shifts.get(&ResidentId(i)).unwrap());
+        }
+    }
+
+    #[rstest]
+    fn test_calculate_max_holiday_shifts_minimal(minimal_config: UserConfig) {
+        let mut bounds = WorkloadBounds::default();
+        bounds.calculate_max_holiday_shifts(
+            &minimal_config.residents,
+            minimal_config.total_holiday_slots,
+        );
+
+        for i in 1..=5 {
+            assert_eq!(3, *bounds.max_holiday_shifts.get(&ResidentId(i)).unwrap());
+        }
+    }
+
+    #[rstest]
+    fn test_calculate_max_holiday_shifts_hard(hard_config: UserConfig) {
+        let mut bounds = WorkloadBounds::default();
+        bounds
+            .calculate_max_holiday_shifts(&hard_config.residents, hard_config.total_holiday_slots);
+
+        for i in 1..=8 {
+            assert_eq!(2, *bounds.max_holiday_shifts.get(&ResidentId(i)).unwrap());
+        }
+    }
+
+    #[rstest]
+    fn test_calculate_max_by_shift_type_minimal(minimal_config: UserConfig) {
+        let mut bounds = WorkloadBounds::default();
+        bounds.calculate_max_workloads(&minimal_config.residents, minimal_config.total_slots);
+        bounds.calculate_max_by_shift_type(&minimal_config.residents);
+        let m = bounds.max_by_shift_type;
+
+        assert_eq!(4, *m.get(&(ResidentId(1), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(4, *m.get(&(ResidentId(1), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(4, *m.get(&(ResidentId(1), ShiftType::Closed)).unwrap());
+
+        assert_eq!(4, *m.get(&(ResidentId(2), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(4, *m.get(&(ResidentId(2), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(4, *m.get(&(ResidentId(2), ShiftType::Closed)).unwrap());
+
+        assert_eq!(4, *m.get(&(ResidentId(3), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(4, *m.get(&(ResidentId(3), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(4, *m.get(&(ResidentId(3), ShiftType::Closed)).unwrap());
+
+        assert_eq!(4, *m.get(&(ResidentId(4), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(4, *m.get(&(ResidentId(4), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(4, *m.get(&(ResidentId(4), ShiftType::Closed)).unwrap());
+
+        assert_eq!(4, *m.get(&(ResidentId(5), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(4, *m.get(&(ResidentId(5), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(4, *m.get(&(ResidentId(5), ShiftType::Closed)).unwrap());
+    }
+
+    #[rstest]
+    fn test_calculate_max_by_shift_type_complex(complex_config: UserConfig) {
+        let mut bounds = WorkloadBounds::default();
+        bounds.calculate_max_workloads(&complex_config.residents, complex_config.total_slots);
+        bounds.calculate_max_by_shift_type(&complex_config.residents);
+        let m = bounds.max_by_shift_type;
+
+        assert_eq!(2, *m.get(&(ResidentId(1), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(2, *m.get(&(ResidentId(1), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(2, *m.get(&(ResidentId(1), ShiftType::Closed)).unwrap());
+
+        assert_eq!(2, *m.get(&(ResidentId(2), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(2, *m.get(&(ResidentId(2), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(2, *m.get(&(ResidentId(2), ShiftType::Closed)).unwrap());
+
+        assert_eq!(2, *m.get(&(ResidentId(3), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(2, *m.get(&(ResidentId(3), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(2, *m.get(&(ResidentId(3), ShiftType::Closed)).unwrap());
+
+        assert_eq!(0, *m.get(&(ResidentId(4), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(0, *m.get(&(ResidentId(4), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(6, *m.get(&(ResidentId(4), ShiftType::Closed)).unwrap());
+
+        assert_eq!(4, *m.get(&(ResidentId(5), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(4, *m.get(&(ResidentId(5), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(0, *m.get(&(ResidentId(5), ShiftType::Closed)).unwrap());
+
+        assert_eq!(3, *m.get(&(ResidentId(6), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(6), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(6), ShiftType::Closed)).unwrap());
+
+        assert_eq!(3, *m.get(&(ResidentId(7), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(7), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(7), ShiftType::Closed)).unwrap());
+
+        assert_eq!(3, *m.get(&(ResidentId(8), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(8), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(8), ShiftType::Closed)).unwrap());
+
+        assert_eq!(3, *m.get(&(ResidentId(9), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(9), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(9), ShiftType::Closed)).unwrap());
+    }
+
+    #[rstest]
+    fn test_calculate_max_by_shift_type_hard(hard_config: UserConfig) {
+        let mut bounds = WorkloadBounds::default();
+        bounds.calculate_max_workloads(&hard_config.residents, hard_config.total_slots);
+        bounds.calculate_max_by_shift_type(&hard_config.residents);
+        let m = bounds.max_by_shift_type;
+
+        assert_eq!(3, *m.get(&(ResidentId(1), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(1), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(1), ShiftType::Closed)).unwrap());
+
+        assert_eq!(3, *m.get(&(ResidentId(2), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(2), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(2), ShiftType::Closed)).unwrap());
+
+        assert_eq!(3, *m.get(&(ResidentId(3), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(3), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(3), ShiftType::Closed)).unwrap());
+
+        assert_eq!(3, *m.get(&(ResidentId(4), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(4), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(4), ShiftType::Closed)).unwrap());
+
+        assert_eq!(3, *m.get(&(ResidentId(5), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(5), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(3, *m.get(&(ResidentId(5), ShiftType::Closed)).unwrap());
+
+        assert_eq!(0, *m.get(&(ResidentId(6), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(5, *m.get(&(ResidentId(6), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(0, *m.get(&(ResidentId(6), ShiftType::Closed)).unwrap());
+
+        assert_eq!(2, *m.get(&(ResidentId(7), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(2, *m.get(&(ResidentId(7), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(2, *m.get(&(ResidentId(7), ShiftType::Closed)).unwrap());
+
+        assert_eq!(0, *m.get(&(ResidentId(8), ShiftType::OpenFirst)).unwrap());
+        assert_eq!(5, *m.get(&(ResidentId(8), ShiftType::OpenSecond)).unwrap());
+        assert_eq!(0, *m.get(&(ResidentId(8), ShiftType::Closed)).unwrap());
     }
 }
diff --git a/src-tauri/tests/integration.rs b/src-tauri/tests/integration.rs
index afcf1d8..952d11e 100644
--- a/src-tauri/tests/integration.rs
+++ b/src-tauri/tests/integration.rs
@@ -2,94 +2,21 @@
 mod integration_tests {
     use rota_lib::{
         config::{ToxicPair, UserConfig},
-        resident::Resident,
-        schedule::{MonthlySchedule, ShiftType},
+        fixtures::{
+            complex_config, hard_config, manual_shifts_heavy_config, maximal_config, minimal_config,
+        },
+        schedule::MonthlySchedule,
         scheduler::Scheduler,
         slot::{Day, ShiftPosition, Slot},
         workload::{WorkloadBounds, WorkloadTracker},
     };
-    use rstest::{fixture, rstest};
+    use rstest::rstest;
 
-    #[fixture]
-    fn minimal_config() -> UserConfig {
-        UserConfig::default().with_residents(vec![
-            Resident::new(1, "R1"),
-            Resident::new(2, "R2"),
-            Resident::new(3, "R3"),
-            Resident::new(4, "R4"),
-        ])
-    }
-
-    #[fixture]
-    fn maximal_config() -> UserConfig {
-        UserConfig::default()
-            .with_holidays(vec![2, 3, 10, 11, 12, 25])
-            .with_residents(vec![
-                Resident::new(1, "R1").with_max_shifts(3),
-                Resident::new(2, "R2").with_max_shifts(4),
-                Resident::new(3, "R3").with_reduced_load(),
-                Resident::new(4, "R4").with_allowed_types(vec![ShiftType::Closed]),
-                Resident::new(5, "R5")
-                    .with_allowed_types(vec![ShiftType::OpenFirst, ShiftType::OpenSecond]),
-                Resident::new(6, "R6").with_negative_shifts(vec![Day(5), Day(15), Day(25)]),
-                Resident::new(7, "R7"),
-                Resident::new(8, "R8"),
-                Resident::new(9, "R9"),
-                Resident::new(10, "R10"),
-            ])
-            .with_toxic_pairs(vec![
-                ToxicPair::new(1, 2),
-                ToxicPair::new(3, 4),
-                ToxicPair::new(7, 8),
-            ])
-    }
-
-    #[fixture]
-    fn manual_shifts_heavy_config() -> UserConfig {
-        UserConfig::default().with_residents(vec![
-            Resident::new(1, "R1").with_manual_shifts(vec![
-                Slot::new(Day(1), ShiftPosition::First),
-                Slot::new(Day(3), ShiftPosition::First),
-                Slot::new(Day(5), ShiftPosition::Second),
-            ]),
-            Resident::new(2, "R2").with_manual_shifts(vec![
-                Slot::new(Day(2), ShiftPosition::First),
-                Slot::new(Day(4), ShiftPosition::First),
-            ]),
-            Resident::new(3, "R3"),
-            Resident::new(4, "R4"),
-            Resident::new(5, "R5"),
-            Resident::new(6, "R6"),
-        ])
-    }
-
-    #[fixture]
-    fn complex_config() -> UserConfig {
-        UserConfig::default()
-            .with_holidays(vec![5, 12, 19, 26])
-            .with_residents(vec![
-                Resident::new(1, "R1")
-                    .with_max_shifts(3)
-                    .with_negative_shifts(vec![Day(1), Day(2), Day(3)]),
-                Resident::new(2, "R2")
-                    .with_max_shifts(3)
-                    .with_negative_shifts(vec![Day(4), Day(5), Day(6)]),
-                Resident::new(3, "R3")
-                    .with_max_shifts(3)
-                    .with_negative_shifts(vec![Day(7), Day(8), Day(9)]),
-                Resident::new(4, "R4").with_allowed_types(vec![ShiftType::Closed]),
-                Resident::new(5, "R5")
-                    .with_allowed_types(vec![ShiftType::OpenFirst, ShiftType::OpenSecond]),
-                Resident::new(6, "R6"),
-                Resident::new(7, "R7"),
-                Resident::new(8, "R8"),
-            ])
-            .with_toxic_pairs(vec![
-                ToxicPair::new(1, 2),
-                ToxicPair::new(2, 3),
-                ToxicPair::new(5, 6),
-                ToxicPair::new(6, 7),
-            ])
+    #[ctor::ctor]
+    fn global_setup() {
+        env_logger::builder()
+            .filter_level(log::LevelFilter::Info)
+            .init();
     }
 
     #[rstest]
@@ -98,8 +25,9 @@ mod integration_tests {
         let mut tracker = WorkloadTracker::default();
         let scheduler = Scheduler::new_with_config(minimal_config.clone());
 
-        assert!(scheduler.run(&mut schedule, &mut tracker)?);
-
+        let solved = scheduler.run(&mut schedule, &mut tracker)?;
+        println!("{}", schedule.report(&minimal_config, &tracker));
+        assert!(solved);
         validate_all_constraints(&schedule, &tracker, &minimal_config);
 
         Ok(())
@@ -111,8 +39,9 @@ mod integration_tests {
         let mut tracker = WorkloadTracker::default();
         let scheduler = Scheduler::new_with_config(maximal_config.clone());
 
-        assert!(scheduler.run(&mut schedule, &mut tracker)?);
-
+        let solved = scheduler.run(&mut schedule, &mut tracker)?;
+        println!("{}", schedule.report(&maximal_config, &tracker));
+        assert!(solved);
         validate_all_constraints(&schedule, &tracker, &maximal_config);
 
         Ok(())
@@ -126,8 +55,9 @@ mod integration_tests {
         let mut tracker = WorkloadTracker::default();
         let scheduler = Scheduler::new_with_config(manual_shifts_heavy_config.clone());
 
-        assert!(scheduler.run(&mut schedule, &mut tracker)?);
-
+        let solved = scheduler.run(&mut schedule, &mut tracker)?;
+        println!("{}", schedule.report(&manual_shifts_heavy_config, &tracker));
+        assert!(solved);
         validate_all_constraints(&schedule, &tracker, &manual_shifts_heavy_config);
 
         Ok(())
@@ -139,13 +69,28 @@ mod integration_tests {
         let mut tracker = WorkloadTracker::default();
         let scheduler = Scheduler::new_with_config(complex_config.clone());
 
-        assert!(scheduler.run(&mut schedule, &mut tracker)?);
-
+        let solved = scheduler.run(&mut schedule, &mut tracker)?;
+        println!("{}", schedule.report(&complex_config, &tracker));
+        assert!(solved);
         validate_all_constraints(&schedule, &tracker, &complex_config);
 
         Ok(())
     }
 
+    #[rstest]
+    fn test_hard_config(hard_config: UserConfig) -> anyhow::Result<()> {
+        let mut schedule = MonthlySchedule::new();
+        let mut tracker = WorkloadTracker::default();
+        let scheduler = Scheduler::new_with_config(hard_config.clone());
+
+        let solved = scheduler.run(&mut schedule, &mut tracker)?;
+        println!("{}", schedule.report(&hard_config, &tracker));
+        assert!(solved);
+        validate_all_constraints(&schedule, &tracker, &hard_config);
+
+        Ok(())
+    }
+
     fn validate_all_constraints(
         schedule: &MonthlySchedule,
         tracker: &WorkloadTracker,
@@ -162,8 +107,8 @@ mod integration_tests {
                 .iter()
                 .filter_map(|&p| schedule.get_resident_id(&Slot::new(Day(d - 1), p)))
                 .collect();
-            for res in current {
-                assert!(!previous.contains(&res));
+            for r in current {
+                assert!(!previous.contains(&r));
             }
         }
 
@@ -181,20 +126,20 @@ mod integration_tests {
         }
 
         let bounds = WorkloadBounds::new_with_config(config);
-        for (slot, res_id) in &schedule.0 {
-            let res = config
+        for (slot, r_id) in &schedule.0 {
+            let r = config
                 .residents
                 .iter()
-                .find(|r| &r.id == res_id)
+                .find(|r| &r.id == r_id)
                 .expect("Resident not found");
-            assert!(res.allowed_types.contains(&slot.shift_type()));
-            assert!(!res.negative_shifts.contains(&slot.day));
+            assert!(r.allowed_types.contains(&slot.shift_type()));
+            assert!(!r.negative_shifts.contains(&slot.day));
         }
 
         for resident in &config.residents {
             let workload = tracker.current_workload(&resident.id);
             let max = *bounds.max_workloads.get(&resident.id).unwrap();
-            assert!(workload <= max);
+            assert!(workload <= max, "workload: {}, max: {}", workload, max);
         }
     }
 }