diff --git a/crates/aiken-lang/src/gen_uplc/decision_tree.rs b/crates/aiken-lang/src/gen_uplc/decision_tree.rs
index 8d591a85..87f39186 100644
--- a/crates/aiken-lang/src/gen_uplc/decision_tree.rs
+++ b/crates/aiken-lang/src/gen_uplc/decision_tree.rs
@@ -1,6 +1,6 @@
 use std::{cmp::Ordering, rc::Rc};
 
-use itertools::Itertools;
+use itertools::{Itertools, Tuples};
 
 use crate::{
     ast::{Pattern, TypedClause, TypedPattern},
@@ -13,60 +13,32 @@ struct Occurrence {
     amount: usize,
 }
 
-#[derive(Clone)]
+#[derive(Clone, Debug)]
+enum Path {
+    Pair(usize),
+    Tuple(usize),
+}
+
+impl Path {
+    pub fn get_index(&self) -> usize {
+        match self {
+            Path::Pair(u) | Path::Tuple(u) => *u,
+        }
+    }
+}
+
+#[derive(Clone, Debug)]
 struct RowItem<'a> {
-    assign: Option<String>,
+    path: Vec<Path>,
     pattern: &'a TypedPattern,
 }
 
-#[derive(Clone, Eq, PartialEq)]
-pub enum CaseTest {
-    Constr(PatternConstructor),
-    Int(String),
-    Bytes(Vec<u8>),
-    List(usize),
-    Wild,
-}
-impl PartialOrd for CaseTest {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        match (self, other) {
-            (CaseTest::Wild, CaseTest::Wild) => Some(Ordering::Equal),
-            (CaseTest::Wild, _) => Some(Ordering::Less),
-            (_, CaseTest::Wild) => Some(Ordering::Greater),
-            (_, _) => Some(Ordering::Equal),
-        }
-    }
-}
-
-impl Ord for CaseTest {
-    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
-        match (self, other) {
-            (CaseTest::Wild, CaseTest::Wild) => Ordering::Equal,
-            (CaseTest::Wild, _) => Ordering::Less,
-            (_, CaseTest::Wild) => Ordering::Greater,
-            (_, _) => Ordering::Equal,
-        }
-    }
-}
-
+#[derive(Clone, Debug)]
 struct Assign {
-    subject_name: String,
-    subject_tuple_index: Option<usize>,
+    path: Vec<Path>,
     assigned: String,
 }
 
-enum DecisionTree {
-    Switch {
-        subject_name: String,
-        subject_tuple_index: Option<usize>,
-        subject_tipo: Rc<Type>,
-        column_to_test: usize,
-        cases: Vec<(CaseTest, DecisionTree)>,
-        default: Box<DecisionTree>,
-    },
-    Leaf(TypedExpr),
-}
-
 struct Row<'a> {
     assigns: Vec<Assign>,
     columns: Vec<RowItem<'a>>,
@@ -77,60 +49,152 @@ struct PatternMatrix<'a> {
     rows: Vec<Row<'a>>,
 }
 
-fn map_to_row<'a>(
+#[derive(Clone, Eq, PartialEq)]
+pub enum CaseTest {
+    Constr(PatternConstructor),
+    Int(String),
+    Bytes(Vec<u8>),
+    List(usize),
+    Wild,
+}
+
+impl PartialOrd for CaseTest {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        match (self, other) {
+            (CaseTest::Wild, CaseTest::Wild) => Some(Ordering::Equal),
+            (CaseTest::Wild, _) => Some(Ordering::Less),
+            (_, CaseTest::Wild) => Some(Ordering::Greater),
+            (_, _) => Some(Ordering::Equal),
+        }
+    }
+}
+
+impl Ord for CaseTest {
+    fn cmp(&self, other: &Self) -> Ordering {
+        match (self, other) {
+            (CaseTest::Wild, CaseTest::Wild) => Ordering::Equal,
+            (CaseTest::Wild, _) => Ordering::Less,
+            (_, CaseTest::Wild) => Ordering::Greater,
+            (_, _) => Ordering::Equal,
+        }
+    }
+}
+
+enum DecisionTree {
+    Switch {
+        subject_name: String,
+        subject_tipo: Rc<Type>,
+        column_to_test: usize,
+        cases: Vec<(CaseTest, Vec<Path>, DecisionTree)>,
+        default: (Vec<Path>, Box<DecisionTree>),
+    },
+    Leaf(TypedExpr),
+}
+
+fn get_tipo_by_path(mut subject_tipo: Rc<Type>, mut path: &[Path]) -> Rc<Type> {
+    while let Some((p, rest)) = path.split_first() {
+        let index = p.get_index();
+
+        subject_tipo = subject_tipo.arg_types().unwrap().remove(index);
+        path = rest
+    }
+    subject_tipo
+}
+
+fn map_pattern_to_row<'a>(
     pattern: &'a TypedPattern,
     subject_name: &String,
-    column_count: usize,
-) -> Vec<RowItem<'a>> {
-    match pattern {
-        Pattern::Var { name, .. } => vec![RowItem {
-            assign: Some(name.clone()),
-            pattern,
-        }]
-        .into_iter()
-        .cycle()
-        .take(column_count)
-        .collect_vec(),
+    subject_tipo: Rc<Type>,
+    path: Vec<Path>,
+) -> (Vec<Assign>, Vec<RowItem<'a>>) {
+    let current_tipo = get_tipo_by_path(subject_tipo.clone(), &path);
 
-        Pattern::Assign { name, pattern, .. } => {
-            let p = map_to_row(pattern, subject_name, column_count);
-            p.into_iter()
-                .map(|mut item| {
-                    item.assign = Some(name.clone());
-                    item
-                })
-                .collect_vec()
-        }
+    let new_columns_added = if current_tipo.is_pair() {
+        2
+    } else if current_tipo.is_tuple() {
+        let Type::Tuple { elems, .. } = subject_tipo.as_ref() else {
+            unreachable!()
+        };
+        elems.len()
+    } else {
+        1
+    };
+
+    match pattern {
+        Pattern::Var { name, .. } => (
+            vec![Assign {
+                path: path.clone(),
+                assigned: name.clone(),
+            }],
+            vec![RowItem {
+                pattern,
+                path: path.clone(),
+            }]
+            .into_iter()
+            .cycle()
+            .take(new_columns_added)
+            .collect_vec(),
+        ),
+
+        Pattern::Assign { name, pattern, .. } => (
+            vec![Assign {
+                path: path.clone(),
+                assigned: name.clone(),
+            }],
+            map_pattern_to_row(pattern, subject_name, subject_tipo.clone(), path).1,
+        ),
         Pattern::Int { .. }
         | Pattern::ByteArray { .. }
         | Pattern::Discard { .. }
         | Pattern::List { .. }
-        | Pattern::Constructor { .. } => vec![RowItem {
-            assign: None,
-            pattern,
-        }]
-        .into_iter()
-        .cycle()
-        .take(column_count)
-        .collect_vec(),
-
-        Pattern::Pair { fst, snd, .. } => vec![
-            RowItem {
-                assign: None,
-                pattern: fst,
-            },
-            RowItem {
-                assign: None,
-                pattern: snd,
-            },
-        ],
-        Pattern::Tuple { elems, .. } => elems
-            .iter()
-            .map(|elem| RowItem {
-                assign: None,
-                pattern: elem,
-            })
+        | Pattern::Constructor { .. } => (
+            vec![],
+            vec![RowItem {
+                pattern,
+                path: path.clone(),
+            }]
+            .into_iter()
+            .cycle()
+            .take(new_columns_added)
             .collect_vec(),
+        ),
+
+        Pattern::Pair { fst, snd, .. } => {
+            let mut fst_path = path.clone();
+            fst_path.push(Path::Pair(0));
+            let mut snd_path = path;
+            snd_path.push(Path::Pair(1));
+
+            let (mut assigns, mut patts) =
+                map_pattern_to_row(fst, subject_name, subject_tipo.clone(), fst_path);
+
+            let (assign_snd, patt_snd) =
+                map_pattern_to_row(snd, subject_name, subject_tipo.clone(), snd_path);
+
+            assigns.extend(assign_snd.into_iter());
+
+            patts.extend(patt_snd.into_iter());
+
+            (assigns, patts)
+        }
+        Pattern::Tuple { elems, .. } => {
+            elems
+                .iter()
+                .enumerate()
+                .fold((vec![], vec![]), |mut acc, (index, item)| {
+                    let mut item_path = path.clone();
+
+                    item_path.push(Path::Tuple(index));
+
+                    let (assigns, patts) =
+                        map_pattern_to_row(item, subject_name, subject_tipo.clone(), item_path);
+
+                    acc.0.extend(assigns.into_iter());
+                    acc.1.extend(patts.into_iter());
+
+                    acc
+                })
+        }
     }
 }
 
@@ -147,64 +211,36 @@ pub fn build_tree(
     subject_tipo: Rc<Type>,
     clauses: &Vec<TypedClause>,
 ) -> DecisionTree {
-    let column_count = if subject_tipo.is_pair() {
-        2
-    } else if subject_tipo.is_tuple() {
-        let Type::Tuple { elems, .. } = subject_tipo.as_ref() else {
-            unreachable!()
-        };
-        elems.len()
-    } else {
-        1
-    };
-
     let rows = clauses
         .iter()
         .map(|clause| {
-            let row_items = map_to_row(&clause.pattern, subject_name, column_count);
+            let (assign, row_items) =
+                map_pattern_to_row(&clause.pattern, subject_name, subject_tipo.clone(), vec![]);
 
             Row {
-                assigns: vec![],
+                assigns: assign.into_iter().collect_vec(),
                 columns: row_items,
                 then: &clause.then,
             }
         })
         .collect_vec();
 
-    let subject_per_column = if column_count > 1 {
-        (0..column_count)
-            .map(|index| (subject_name.clone(), Some(index)))
-            .collect_vec()
-    } else {
-        vec![(subject_name.clone(), None)]
-    };
-
-    do_build_tree(
-        subject_name,
-        subject_tipo,
-        subject_per_column,
-        PatternMatrix { rows },
-    )
+    do_build_tree(subject_name, &subject_tipo, PatternMatrix { rows })
 }
 
 pub fn do_build_tree<'a>(
     subject_name: &String,
-    subject_tipo: Rc<Type>,
-    subject_per_column: Vec<(String, Option<usize>)>,
+    subject_tipo: &Rc<Type>,
     matrix: PatternMatrix<'a>,
 ) -> DecisionTree {
-    let column_count = if subject_tipo.is_pair() {
-        2
-    } else if subject_tipo.is_tuple() {
-        let Type::Tuple { elems, .. } = subject_tipo.as_ref() else {
-            unreachable!()
-        };
-        elems.len()
-    } else {
-        1
-    };
+    let column_length = matrix.rows[0].columns.len();
 
-    let occurrences = [Occurrence::default()].repeat(column_count);
+    assert!(matrix
+        .rows
+        .iter()
+        .all(|row| { row.columns.len() == column_length }));
+
+    let occurrences = [Occurrence::default()].repeat(column_length);
 
     let occurrences =
         matrix
@@ -238,10 +274,9 @@ pub fn do_build_tree<'a>(
         }
     });
 
-    if column_count > 1 {
+    if column_length > 1 {
         DecisionTree::Switch {
             subject_name: subject_name.clone(),
-            subject_tuple_index: None,
             subject_tipo: subject_tipo.clone(),
             column_to_test: highest_occurrence.0,
             cases: todo!(),
@@ -250,42 +285,53 @@ pub fn do_build_tree<'a>(
     } else {
         let mut collection_vec = matrix.rows.into_iter().fold(
             vec![],
-            |mut collection_vec: Vec<(CaseTest, Vec<Row<'a>>)>, mut item: Row<'a>| {
+            |mut collection_vec: Vec<(CaseTest, Vec<Path>, Vec<Row<'a>>)>, mut item: Row<'a>| {
                 let col = item.columns.remove(highest_occurrence.0);
-                let mut patt = col.pattern;
 
-                if let Pattern::Assign { pattern, .. } = patt {
-                    patt = pattern;
-                }
+                assert!(!matches!(col.pattern, Pattern::Assign { .. }));
 
-                if let Some(assign) = col.assign {
-                    item.assigns.push(Assign {
-                        subject_name: subject_name.clone(),
-                        subject_tuple_index: None,
-                        assigned: assign,
-                    });
-                }
+                let (mapped_args, case) = match col.pattern {
+                    Pattern::Int { value, .. } => (vec![], CaseTest::Int(value.clone())),
+                    Pattern::ByteArray { value, .. } => (vec![], CaseTest::Bytes(value.clone())),
+                    Pattern::Var { .. } | Pattern::Discard { .. } => (vec![], CaseTest::Wild),
+                    Pattern::List { elements, .. } => (
+                        elements
+                            .iter()
+                            .enumerate()
+                            .map(|(index, item)| {
+                                let mut item_path = col.path.clone();
 
-                let case = match patt {
-                    Pattern::Int { value, .. } => CaseTest::Int(value.clone()),
-                    Pattern::ByteArray { value, .. } => CaseTest::Bytes(value.clone()),
-                    Pattern::Var { .. } | Pattern::Discard { .. } => CaseTest::Wild,
-                    Pattern::List { elements, .. } => CaseTest::List(elements.len()),
-                    Pattern::Constructor { constructor, .. } => {
-                        CaseTest::Constr(constructor.clone())
+                                item_path.push(Path::Tuple(index));
+
+                                map_pattern_to_row(
+                                    item,
+                                    subject_name,
+                                    subject_tipo.clone(),
+                                    item_path,
+                                )
+                            })
+                            .collect_vec(),
+                        CaseTest::List(elements.len()),
+                    ),
+
+                    Pattern::Constructor { .. } => {
+                        todo!()
                     }
-                    Pattern::Pair { .. } => todo!(),
-                    Pattern::Tuple { .. } => todo!(),
-                    _ => unreachable!(),
+                    _ => unreachable!("{:#?}", col.pattern),
                 };
 
+                item.assigns
+                    .extend(mapped_args.iter().map(|x| x.0.clone()).flatten());
+                item.columns
+                    .extend(mapped_args.into_iter().map(|x| x.1).flatten());
+
                 if let Some(index) = collection_vec.iter().position(|item| item.0 == case) {
                     let entry = collection_vec.get_mut(index).unwrap();
 
-                    entry.1.push(item);
+                    entry.2.push(item);
                     collection_vec
                 } else {
-                    collection_vec.push((case, vec![item]));
+                    collection_vec.push((case, col.path, vec![item]));
 
                     collection_vec
                 }
@@ -293,27 +339,31 @@ pub fn do_build_tree<'a>(
         );
 
         collection_vec.sort_by(|a, b| a.0.cmp(&b.0));
-        let mut collection_iter = collection_vec.into_iter().peekable();
+        let mut collection_iter = collection_vec
+            .into_iter()
+            .map(|x| {
+                (
+                    x.0,
+                    x.1,
+                    do_build_tree(subject_name, subject_tipo, PatternMatrix { rows: x.2 }),
+                )
+            })
+            .peekable();
 
         let cases = collection_iter
             .peeking_take_while(|a| !matches!(a.0, CaseTest::Wild))
             .collect_vec();
 
-        let mut fallback = collection_iter.collect_vec();
+        let mut fallback = collection_iter.map(|x| (x.1, x.2.into())).collect_vec();
 
         assert!(fallback.len() == 1);
 
-        let fallback_matrix = PatternMatrix {
-            rows: fallback.remove(0).1,
-        };
-
         DecisionTree::Switch {
             subject_name: subject_name.clone(),
-            subject_tuple_index: None,
             subject_tipo: subject_tipo.clone(),
             column_to_test: highest_occurrence.0,
-            cases: todo!(),
-            default: todo!(),
+            cases,
+            default: fallback.remove(0),
         }
     };