diff --git a/compiler/noirc_driver/src/lib.rs b/compiler/noirc_driver/src/lib.rs
index 97fc66688e1..fa134f8a0dd 100644
--- a/compiler/noirc_driver/src/lib.rs
+++ b/compiler/noirc_driver/src/lib.rs
@@ -237,11 +237,8 @@ pub fn check_crate(
     deny_warnings: bool,
     disable_macros: bool,
 ) -> CompilationResult<()> {
-    let macros: Vec<&dyn MacroProcessor> = if disable_macros {
-        vec![]
-    } else {
-        vec![&aztec_macros::AztecMacro as &dyn MacroProcessor]
-    };
+    let macros: &[&dyn MacroProcessor] =
+        if disable_macros { &[] } else { &[&aztec_macros::AztecMacro as &dyn MacroProcessor] };
 
     let mut errors = vec![];
     let diagnostics = CrateDefMap::collect_defs(crate_id, context, macros);
diff --git a/compiler/noirc_errors/src/debug_info.rs b/compiler/noirc_errors/src/debug_info.rs
index 67ec851d46d..09117bdc3b7 100644
--- a/compiler/noirc_errors/src/debug_info.rs
+++ b/compiler/noirc_errors/src/debug_info.rs
@@ -24,6 +24,9 @@ use serde::{
 #[derive(Debug, Clone, Copy, Eq, PartialEq, Hash, PartialOrd, Ord, Deserialize, Serialize)]
 pub struct DebugVarId(pub u32);
 
+#[derive(Debug, Clone, Copy, Eq, PartialEq, Hash, PartialOrd, Ord, Deserialize, Serialize)]
+pub struct DebugFnId(pub u32);
+
 #[derive(Debug, Clone, Copy, Eq, PartialEq, Hash, PartialOrd, Ord, Deserialize, Serialize)]
 pub struct DebugTypeId(pub u32);
 
@@ -33,7 +36,14 @@ pub struct DebugVariable {
     pub debug_type_id: DebugTypeId,
 }
 
+#[derive(Debug, Clone, Hash, Deserialize, Serialize)]
+pub struct DebugFunction {
+    pub name: String,
+    pub arg_names: Vec<String>,
+}
+
 pub type DebugVariables = BTreeMap<DebugVarId, DebugVariable>;
+pub type DebugFunctions = BTreeMap<DebugFnId, DebugFunction>;
 pub type DebugTypes = BTreeMap<DebugTypeId, PrintableType>;
 
 #[serde_as]
@@ -45,6 +55,7 @@ pub struct DebugInfo {
     #[serde_as(as = "BTreeMap<DisplayFromStr, _>")]
     pub locations: BTreeMap<OpcodeLocation, Vec<Location>>,
     pub variables: DebugVariables,
+    pub functions: DebugFunctions,
     pub types: DebugTypes,
 }
 
@@ -60,9 +71,10 @@ impl DebugInfo {
     pub fn new(
         locations: BTreeMap<OpcodeLocation, Vec<Location>>,
         variables: DebugVariables,
+        functions: DebugFunctions,
         types: DebugTypes,
     ) -> Self {
-        Self { locations, variables, types }
+        Self { locations, variables, functions, types }
     }
 
     /// Updates the locations map when the [`Circuit`][acvm::acir::circuit::Circuit] is modified.
diff --git a/compiler/noirc_evaluator/src/ssa.rs b/compiler/noirc_evaluator/src/ssa.rs
index 0bb81efe977..56cb76adbe4 100644
--- a/compiler/noirc_evaluator/src/ssa.rs
+++ b/compiler/noirc_evaluator/src/ssa.rs
@@ -88,6 +88,7 @@ pub fn create_circuit(
 ) -> Result<(Circuit, DebugInfo, Vec<Witness>, Vec<Witness>, Vec<SsaReport>), RuntimeError> {
     let debug_variables = program.debug_variables.clone();
     let debug_types = program.debug_types.clone();
+    let debug_functions = program.debug_functions.clone();
     let func_sig = program.main_function_signature.clone();
     let recursive = program.recursive;
     let mut generated_acir = optimize_into_acir(
@@ -130,7 +131,7 @@ pub fn create_circuit(
         .map(|(index, locations)| (index, locations.into_iter().collect()))
         .collect();
 
-    let mut debug_info = DebugInfo::new(locations, debug_variables, debug_types);
+    let mut debug_info = DebugInfo::new(locations, debug_variables, debug_functions, debug_types);
 
     // Perform any ACIR-level optimizations
     let (optimized_circuit, transformation_map) = acvm::compiler::optimize(circuit);
diff --git a/compiler/noirc_evaluator/src/ssa/opt/flatten_cfg.rs b/compiler/noirc_evaluator/src/ssa/opt/flatten_cfg.rs
index 943a57c1bc0..46f1e7a2765 100644
--- a/compiler/noirc_evaluator/src/ssa/opt/flatten_cfg.rs
+++ b/compiler/noirc_evaluator/src/ssa/opt/flatten_cfg.rs
@@ -199,22 +199,47 @@ struct Context<'f> {
     /// found, the top of this conditions stack is popped since we are no longer under that
     /// condition. If we are under multiple conditions (a nested if), the topmost condition is
     /// the most recent condition combined with all previous conditions via `And` instructions.
-    conditions: Vec<(BasicBlockId, ValueId)>,
+    condition_stack: Vec<ConditionalContext>,
 
     /// Maps SSA array values with a slice type to their size.
     /// This is maintained by appropriate calls to the `SliceCapacityTracker` and is used by the `ValueMerger`.
     slice_sizes: HashMap<ValueId, usize>,
+
+    /// Stack of block arguments
+    /// When processing a block, we pop this stack to get its arguments
+    /// and at the end we push the arguments for his successor
+    arguments_stack: Vec<Vec<ValueId>>,
 }
 
+#[derive(Clone)]
 pub(crate) struct Store {
     old_value: ValueId,
     new_value: ValueId,
 }
 
-struct Branch {
-    condition: ValueId,
+#[derive(Clone)]
+struct ConditionalBranch {
+    // Contains the last processed block during the processing of the branch.
     last_block: BasicBlockId,
+    // The unresolved condition of the branch
+    old_condition: ValueId,
+    // The condition of the branch
+    condition: ValueId,
+    // The store values accumulated when processing the branch
     store_values: HashMap<ValueId, Store>,
+    // The allocations accumulated when processing the branch
+    local_allocations: HashSet<ValueId>,
+}
+
+struct ConditionalContext {
+    // Condition from the conditional statement
+    condition: ValueId,
+    // Block containing the conditional statement
+    entry_block: BasicBlockId,
+    // First block of the then branch
+    then_branch: ConditionalBranch,
+    // First block of the else branch
+    else_branch: Option<ConditionalBranch>,
 }
 
 fn flatten_function_cfg(function: &mut Function) {
@@ -233,90 +258,117 @@ fn flatten_function_cfg(function: &mut Function) {
         store_values: HashMap::default(),
         local_allocations: HashSet::new(),
         branch_ends,
-        conditions: Vec::new(),
         slice_sizes: HashMap::default(),
+        condition_stack: Vec::new(),
+        arguments_stack: Vec::new(),
     };
     context.flatten();
 }
 
 impl<'f> Context<'f> {
     fn flatten(&mut self) {
-        // Start with following the terminator of the entry block since we don't
-        // need to flatten the entry block into itself.
-        self.handle_terminator(self.inserter.function.entry_block());
+        // Flatten the CFG by inlining all instructions from the queued blocks
+        // until all blocks have been flattened.
+        // We follow the terminator of each block to determine which blocks to
+        // process next
+        let mut queue = vec![self.inserter.function.entry_block()];
+        while let Some(block) = queue.pop() {
+            self.inline_block(block);
+            let to_process = self.handle_terminator(block, &queue);
+            for incoming_block in to_process {
+                if !queue.contains(&incoming_block) {
+                    queue.push(incoming_block);
+                }
+            }
+        }
     }
 
-    /// Check the terminator of the given block and recursively inline any blocks reachable from
-    /// it. Since each block from a jmpif terminator is inlined successively, we must handle
-    /// instructions with side effects like constrain and store specially to preserve correctness.
-    /// For these instructions we must keep track of what the current condition is and modify
-    /// the instructions according to the module-level comment at the top of this file. Note that
-    /// the current condition is all the jmpif conditions required to reach the current block,
-    /// combined via `And` instructions.
-    ///
-    /// Returns the last block to be inlined. This is either the return block of the function or,
-    /// if self.conditions is not empty, the end block of the most recent condition.
-    fn handle_terminator(&mut self, block: BasicBlockId) -> BasicBlockId {
-        // As we recursively flatten inner blocks, we need to track the slice information
-        // for the outer block before we start recursively inlining
-        let outer_block_instructions = self.inserter.function.dfg[block].instructions();
-        let mut capacity_tracker = SliceCapacityTracker::new(&self.inserter.function.dfg);
-        for instruction in outer_block_instructions {
-            let results = self.inserter.function.dfg.instruction_results(*instruction);
-            let instruction = &self.inserter.function.dfg[*instruction];
+    /// Returns the updated condition so that
+    /// it is 'AND-ed' with the previous condition (if any)
+    fn link_condition(&mut self, condition: ValueId) -> ValueId {
+        // Retrieve the previous condition
+        if let Some(context) = self.condition_stack.last() {
+            let previous_branch = context.else_branch.as_ref().unwrap_or(&context.then_branch);
+            let and = Instruction::binary(BinaryOp::And, previous_branch.condition, condition);
+            self.insert_instruction(and, CallStack::new())
+        } else {
+            condition
+        }
+    }
+
+    /// Returns the current condition
+    fn get_last_condition(&self) -> Option<ValueId> {
+        self.condition_stack.last().map(|context| match &context.else_branch {
+            Some(else_branch) => else_branch.condition,
+            None => context.then_branch.condition,
+        })
+    }
+
+    // Inline all instructions from the given block into the entry block, and track slice capacities
+    fn inline_block(&mut self, block: BasicBlockId) {
+        if self.inserter.function.entry_block() == block {
+            // we do not inline the entry block into itself
+            // for the outer block before we start inlining
+            let outer_block_instructions = self.inserter.function.dfg[block].instructions();
+            let mut capacity_tracker = SliceCapacityTracker::new(&self.inserter.function.dfg);
+            for instruction in outer_block_instructions {
+                let results = self.inserter.function.dfg.instruction_results(*instruction);
+                let instruction = &self.inserter.function.dfg[*instruction];
+                capacity_tracker.collect_slice_information(
+                    instruction,
+                    &mut self.slice_sizes,
+                    results.to_vec(),
+                );
+            }
+
+            return;
+        }
+
+        let arguments = self.arguments_stack.pop().unwrap();
+        self.inserter.remember_block_params(block, &arguments);
+
+        // If this is not a separate variable, clippy gets confused and says the to_vec is
+        // unnecessary, when removing it actually causes an aliasing/mutability error.
+        let instructions = self.inserter.function.dfg[block].instructions().to_vec();
+        for instruction in instructions.iter() {
+            let results = self.push_instruction(*instruction);
+            let (instruction, _) = self.inserter.map_instruction(*instruction);
+            let mut capacity_tracker = SliceCapacityTracker::new(&self.inserter.function.dfg);
             capacity_tracker.collect_slice_information(
-                instruction,
+                &instruction,
                 &mut self.slice_sizes,
-                results.to_vec(),
+                results,
             );
         }
+    }
 
-        match self.inserter.function.dfg[block].unwrap_terminator() {
+    /// Returns the list of blocks that need to be processed after the given block
+    /// For a normal block, it would be its successor
+    /// For blocks related to a conditional statement, we ensure to process
+    /// the 'then-branch', then the 'else-branch' (if it exists), and finally the end block
+    fn handle_terminator(
+        &mut self,
+        block: BasicBlockId,
+        work_list: &[BasicBlockId],
+    ) -> Vec<BasicBlockId> {
+        let terminator = self.inserter.function.dfg[block].unwrap_terminator().clone();
+        match &terminator {
             TerminatorInstruction::JmpIf { condition, then_destination, else_destination } => {
-                let old_condition = *condition;
-                let then_block = *then_destination;
-                let else_block = *else_destination;
-                let then_condition = self.inserter.resolve(old_condition);
-
-                let one = FieldElement::one();
-                let then_branch =
-                    self.inline_branch(block, then_block, old_condition, then_condition, one);
-
-                let else_condition =
-                    self.insert_instruction(Instruction::Not(then_condition), CallStack::new());
-                let zero = FieldElement::zero();
-
-                // Make sure the else branch sees the previous values of each store
-                // rather than any values created in the 'then' branch.
-                self.undo_stores_in_then_branch(&then_branch);
-
-                let else_branch =
-                    self.inline_branch(block, else_block, old_condition, else_condition, zero);
-
-                // We must remember to reset whether side effects are enabled when both branches
-                // end, in addition to resetting the value of old_condition since it is set to
-                // known to be true/false within the then/else branch respectively.
-                self.insert_current_side_effects_enabled();
-
-                // We must map back to `then_condition` here. Mapping `old_condition` to itself would
-                // lose any previous mappings.
-                self.inserter.map_value(old_condition, then_condition);
-
-                // While there is a condition on the stack we don't compile outside the condition
-                // until it is popped. This ensures we inline the full then and else branches
-                // before continuing from the end of the conditional here where they can be merged properly.
-                let end = self.branch_ends[&block];
-                self.inline_branch_end(end, then_branch, else_branch)
+                self.arguments_stack.push(vec![]);
+                self.if_start(condition, then_destination, else_destination, &block)
             }
             TerminatorInstruction::Jmp { destination, arguments, call_stack: _ } => {
-                if let Some((end_block, _)) = self.conditions.last() {
-                    if destination == end_block {
-                        return block;
+                let arguments = vecmap(arguments.clone(), |value| self.inserter.resolve(value));
+                self.arguments_stack.push(arguments);
+                if work_list.contains(destination) {
+                    if work_list.last() == Some(destination) {
+                        self.else_stop(&block)
+                    } else {
+                        self.then_stop(&block)
                     }
+                } else {
+                    vec![*destination]
                 }
-                let destination = *destination;
-                let arguments = vecmap(arguments.clone(), |value| self.inserter.resolve(value));
-                self.inline_block(destination, &arguments)
             }
             TerminatorInstruction::Return { return_values, call_stack } => {
                 let call_stack = call_stack.clone();
@@ -326,133 +378,133 @@ impl<'f> Context<'f> {
                 let entry = self.inserter.function.entry_block();
 
                 self.inserter.function.dfg.set_block_terminator(entry, new_return);
-                block
+                vec![]
             }
         }
     }
 
-    /// Push a condition to the stack of conditions.
-    ///
-    /// This condition should be present while we're inlining each block reachable from the 'then'
-    /// branch of a jmpif instruction, until the branches eventually join back together. Likewise,
-    /// !condition should be present while we're inlining each block reachable from the 'else'
-    /// branch of a jmpif instruction until the join block.
-    fn push_condition(&mut self, start_block: BasicBlockId, condition: ValueId) {
-        let end_block = self.branch_ends[&start_block];
-
-        if let Some((_, previous_condition)) = self.conditions.last() {
-            let and = Instruction::binary(BinaryOp::And, *previous_condition, condition);
-            let new_condition = self.insert_instruction(and, CallStack::new());
-            self.conditions.push((end_block, new_condition));
-        } else {
-            self.conditions.push((end_block, condition));
+    /// Process a conditional statement
+    fn if_start(
+        &mut self,
+        condition: &ValueId,
+        then_destination: &BasicBlockId,
+        else_destination: &BasicBlockId,
+        if_entry: &BasicBlockId,
+    ) -> Vec<BasicBlockId> {
+        // manage conditions
+        let old_condition = *condition;
+        let then_condition = self.inserter.resolve(old_condition);
+
+        let one = FieldElement::one();
+        let old_stores = std::mem::take(&mut self.store_values);
+        let old_allocations = std::mem::take(&mut self.local_allocations);
+        let branch = ConditionalBranch {
+            old_condition,
+            condition: self.link_condition(then_condition),
+            store_values: old_stores,
+            local_allocations: old_allocations,
+            last_block: *then_destination,
+        };
+        let cond_context = ConditionalContext {
+            condition: then_condition,
+            entry_block: *if_entry,
+            then_branch: branch,
+            else_branch: None,
+        };
+        self.condition_stack.push(cond_context);
+        self.insert_current_side_effects_enabled();
+        // Optimization: within the then branch we know the condition to be true, so replace
+        // any references of it within this branch with true. Likewise, do the same with false
+        // with the else branch. We must be careful not to replace the condition if it is a
+        // known constant, otherwise we can end up setting 1 = 0 or vice-versa.
+        if self.inserter.function.dfg.get_numeric_constant(old_condition).is_none() {
+            let known_value = self.inserter.function.dfg.make_constant(one, Type::bool());
+
+            self.inserter.map_value(old_condition, known_value);
         }
+        vec![self.branch_ends[if_entry], *else_destination, *then_destination]
     }
 
-    /// Insert a new instruction into the function's entry block.
-    /// Unlike push_instruction, this function will not map any ValueIds.
-    /// within the given instruction, nor will it modify self.values in any way.
-    fn insert_instruction(&mut self, instruction: Instruction, call_stack: CallStack) -> ValueId {
-        let block = self.inserter.function.entry_block();
-        self.inserter
-            .function
-            .dfg
-            .insert_instruction_and_results(instruction, block, None, call_stack)
-            .first()
+    /// Switch context to the 'else-branch'
+    fn then_stop(&mut self, block: &BasicBlockId) -> Vec<BasicBlockId> {
+        let mut cond_context = self.condition_stack.pop().unwrap();
+        cond_context.then_branch.last_block = *block;
+
+        let else_condition =
+            self.insert_instruction(Instruction::Not(cond_context.condition), CallStack::new());
+        let else_condition = self.link_condition(else_condition);
+
+        let zero = FieldElement::zero();
+        // Make sure the else branch sees the previous values of each store
+        // rather than any values created in the 'then' branch.
+        let old_stores = std::mem::take(&mut cond_context.then_branch.store_values);
+        cond_context.then_branch.store_values = std::mem::take(&mut self.store_values);
+        self.undo_stores_in_then_branch(&cond_context.then_branch.store_values);
+
+        let old_allocations = std::mem::take(&mut self.local_allocations);
+        let else_branch = ConditionalBranch {
+            old_condition: cond_context.then_branch.old_condition,
+            condition: else_condition,
+            store_values: old_stores,
+            local_allocations: old_allocations,
+            last_block: *block,
+        };
+        let old_condition = else_branch.old_condition;
+        cond_context.then_branch.local_allocations.clear();
+        cond_context.else_branch = Some(else_branch);
+        self.condition_stack.push(cond_context);
+
+        self.insert_current_side_effects_enabled();
+        // Optimization: within the then branch we know the condition to be true, so replace
+        // any references of it within this branch with true. Likewise, do the same with false
+        // with the else branch. We must be careful not to replace the condition if it is a
+        // known constant, otherwise we can end up setting 1 = 0 or vice-versa.
+        if self.inserter.function.dfg.get_numeric_constant(old_condition).is_none() {
+            let known_value = self.inserter.function.dfg.make_constant(zero, Type::bool());
+
+            self.inserter.map_value(old_condition, known_value);
+        }
+        assert_eq!(self.cfg.successors(*block).len(), 1);
+        vec![self.cfg.successors(*block).next().unwrap()]
     }
 
-    /// Inserts a new instruction into the function's entry block, using the given
-    /// control type variables to specify result types if needed.
-    /// Unlike push_instruction, this function will not map any ValueIds.
-    /// within the given instruction, nor will it modify self.values in any way.
-    fn insert_instruction_with_typevars(
-        &mut self,
-        instruction: Instruction,
-        ctrl_typevars: Option<Vec<Type>>,
-    ) -> InsertInstructionResult {
-        let block = self.inserter.function.entry_block();
-        self.inserter.function.dfg.insert_instruction_and_results(
-            instruction,
-            block,
-            ctrl_typevars,
-            CallStack::new(),
-        )
-    }
+    /// Process the 'exit' block of a conditional statement
+    fn else_stop(&mut self, block: &BasicBlockId) -> Vec<BasicBlockId> {
+        let mut cond_context = self.condition_stack.pop().unwrap();
+        if cond_context.else_branch.is_none() {
+            // then_stop() has not been called, this means that the conditional statement has no else branch
+            // so we simply do the then_stop() now
+            self.condition_stack.push(cond_context);
+            self.then_stop(block);
+            cond_context = self.condition_stack.pop().unwrap();
+        }
 
-    /// Checks the branch condition on the top of the stack and uses it to build and insert an
-    /// `EnableSideEffects` instruction into the entry block.
-    ///
-    /// If the stack is empty, a "true" u1 constant is taken to be the active condition. This is
-    /// necessary for re-enabling side-effects when re-emerging to a branch depth of 0.
-    fn insert_current_side_effects_enabled(&mut self) {
-        let condition = match self.conditions.last() {
-            Some((_, cond)) => *cond,
-            None => {
-                self.inserter.function.dfg.make_constant(FieldElement::one(), Type::unsigned(1))
-            }
-        };
-        let enable_side_effects = Instruction::EnableSideEffects { condition };
-        self.insert_instruction_with_typevars(enable_side_effects, None);
-    }
+        let mut else_branch = cond_context.else_branch.unwrap();
+        let stores_in_branch = std::mem::replace(&mut self.store_values, else_branch.store_values);
+        self.local_allocations = std::mem::take(&mut else_branch.local_allocations);
+        else_branch.last_block = *block;
+        else_branch.store_values = stores_in_branch;
+        cond_context.else_branch = Some(else_branch);
 
-    /// Inline one branch of a jmpif instruction.
-    ///
-    /// This will continue inlining recursively until the next end block is reached where each branch
-    /// of the jmpif instruction is joined back into a single block.
-    ///
-    /// Within a branch of a jmpif instruction, we can assume the condition of the jmpif to be
-    /// always true or false, depending on which branch we're in.
-    ///
-    /// Returns the ending block / join block of this branch.
-    fn inline_branch(
-        &mut self,
-        jmpif_block: BasicBlockId,
-        destination: BasicBlockId,
-        old_condition: ValueId,
-        new_condition: ValueId,
-        condition_value: FieldElement,
-    ) -> Branch {
-        if destination == self.branch_ends[&jmpif_block] {
-            // If the branch destination is the same as the end of the branch, this must be the
-            // 'else' case of an if with no else - so there is no else branch.
-            Branch {
-                condition: new_condition,
-                // The last block here is somewhat arbitrary. It only matters that it has no Jmp
-                // args that will be merged by inline_branch_end. Since jmpifs don't have
-                // block arguments, it is safe to use the jmpif block here.
-                last_block: jmpif_block,
-                store_values: HashMap::default(),
-            }
-        } else {
-            self.push_condition(jmpif_block, new_condition);
-            self.insert_current_side_effects_enabled();
-            let old_stores = std::mem::take(&mut self.store_values);
-            let old_allocations = std::mem::take(&mut self.local_allocations);
-
-            // Optimization: within the then branch we know the condition to be true, so replace
-            // any references of it within this branch with true. Likewise, do the same with false
-            // with the else branch. We must be careful not to replace the condition if it is a
-            // known constant, otherwise we can end up setting 1 = 0 or vice-versa.
-            if self.inserter.function.dfg.get_numeric_constant(old_condition).is_none() {
-                let known_value =
-                    self.inserter.function.dfg.make_constant(condition_value, Type::bool());
-
-                self.inserter.map_value(old_condition, known_value);
-            }
+        // We must remember to reset whether side effects are enabled when both branches
+        // end, in addition to resetting the value of old_condition since it is set to
+        // known to be true/false within the then/else branch respectively.
+        self.insert_current_side_effects_enabled();
 
-            let final_block = self.inline_block(destination, &[]);
+        // We must map back to `then_condition` here. Mapping `old_condition` to itself would
+        // lose any previous mappings.
+        self.inserter
+            .map_value(cond_context.then_branch.old_condition, cond_context.then_branch.condition);
 
-            self.conditions.pop();
+        // While there is a condition on the stack we don't compile outside the condition
+        // until it is popped. This ensures we inline the full then and else branches
+        // before continuing from the end of the conditional here where they can be merged properly.
+        let end = self.branch_ends[&cond_context.entry_block];
 
-            let stores_in_branch = std::mem::replace(&mut self.store_values, old_stores);
-            self.local_allocations = old_allocations;
+        // Merge arguments and stores from the else/end branches
+        self.inline_branch_end(end, cond_context);
 
-            Branch {
-                condition: new_condition,
-                last_block: final_block,
-                store_values: stores_in_branch,
-            }
-        }
+        vec![self.cfg.successors(*block).next().unwrap()]
     }
 
     /// Inline the ending block of a branch, the point where all blocks from a jmpif instruction
@@ -467,15 +519,17 @@ impl<'f> Context<'f> {
     fn inline_branch_end(
         &mut self,
         destination: BasicBlockId,
-        then_branch: Branch,
-        else_branch: Branch,
+        cond_context: ConditionalContext,
     ) -> BasicBlockId {
         assert_eq!(self.cfg.predecessors(destination).len(), 2);
+        let last_then = cond_context.then_branch.last_block;
+        let mut else_args = Vec::new();
+        if cond_context.else_branch.is_some() {
+            let last_else = cond_context.else_branch.clone().unwrap().last_block;
+            else_args = self.inserter.function.dfg[last_else].terminator_arguments().to_vec();
+        }
 
-        let then_args =
-            self.inserter.function.dfg[then_branch.last_block].terminator_arguments().to_vec();
-        let else_args =
-            self.inserter.function.dfg[else_branch.last_block].terminator_arguments().to_vec();
+        let then_args = self.inserter.function.dfg[last_then].terminator_arguments().to_vec();
 
         let params = self.inserter.function.dfg.block_parameters(destination);
         assert_eq!(params.len(), then_args.len());
@@ -500,17 +554,64 @@ impl<'f> Context<'f> {
         // Cannot include this in the previous vecmap since it requires exclusive access to self
         let args = vecmap(args, |(then_arg, else_arg)| {
             value_merger.merge_values(
-                then_branch.condition,
-                else_branch.condition,
+                cond_context.then_branch.condition,
+                cond_context.else_branch.clone().unwrap().condition,
                 then_arg,
                 else_arg,
             )
         });
 
-        self.merge_stores(then_branch, else_branch);
+        self.merge_stores(cond_context.then_branch, cond_context.else_branch);
+        self.arguments_stack.pop();
+        self.arguments_stack.pop();
+        self.arguments_stack.push(args);
+        destination
+    }
 
-        // insert merge instruction
-        self.inline_block(destination, &args)
+    /// Insert a new instruction into the function's entry block.
+    /// Unlike push_instruction, this function will not map any ValueIds.
+    /// within the given instruction, nor will it modify self.values in any way.
+    fn insert_instruction(&mut self, instruction: Instruction, call_stack: CallStack) -> ValueId {
+        let block = self.inserter.function.entry_block();
+        self.inserter
+            .function
+            .dfg
+            .insert_instruction_and_results(instruction, block, None, call_stack)
+            .first()
+    }
+
+    /// Inserts a new instruction into the function's entry block, using the given
+    /// control type variables to specify result types if needed.
+    /// Unlike push_instruction, this function will not map any ValueIds.
+    /// within the given instruction, nor will it modify self.values in any way.
+    fn insert_instruction_with_typevars(
+        &mut self,
+        instruction: Instruction,
+        ctrl_typevars: Option<Vec<Type>>,
+    ) -> InsertInstructionResult {
+        let block = self.inserter.function.entry_block();
+        self.inserter.function.dfg.insert_instruction_and_results(
+            instruction,
+            block,
+            ctrl_typevars,
+            CallStack::new(),
+        )
+    }
+
+    /// Checks the branch condition on the top of the stack and uses it to build and insert an
+    /// `EnableSideEffects` instruction into the entry block.
+    ///
+    /// If the stack is empty, a "true" u1 constant is taken to be the active condition. This is
+    /// necessary for re-enabling side-effects when re-emerging to a branch depth of 0.
+    fn insert_current_side_effects_enabled(&mut self) {
+        let condition = match self.get_last_condition() {
+            Some(cond) => cond,
+            None => {
+                self.inserter.function.dfg.make_constant(FieldElement::one(), Type::unsigned(1))
+            }
+        };
+        let enable_side_effects = Instruction::EnableSideEffects { condition };
+        self.insert_instruction_with_typevars(enable_side_effects, None);
     }
 
     /// Merge any store instructions found in each branch.
@@ -518,7 +619,11 @@ impl<'f> Context<'f> {
     /// This function relies on the 'then' branch being merged before the 'else' branch of a jmpif
     /// instruction. If this ordering is changed, the ordering that store values are merged within
     /// this function also needs to be changed to reflect that.
-    fn merge_stores(&mut self, then_branch: Branch, else_branch: Branch) {
+    fn merge_stores(
+        &mut self,
+        then_branch: ConditionalBranch,
+        else_branch: Option<ConditionalBranch>,
+    ) {
         // Address -> (then_value, else_value, value_before_the_if)
         let mut new_map = BTreeMap::new();
 
@@ -526,11 +631,13 @@ impl<'f> Context<'f> {
             new_map.insert(address, (store.new_value, store.old_value, store.old_value));
         }
 
-        for (address, store) in else_branch.store_values {
-            if let Some(entry) = new_map.get_mut(&address) {
-                entry.1 = store.new_value;
-            } else {
-                new_map.insert(address, (store.old_value, store.new_value, store.old_value));
+        if else_branch.is_some() {
+            for (address, store) in else_branch.clone().unwrap().store_values {
+                if let Some(entry) = new_map.get_mut(&address) {
+                    entry.1 = store.new_value;
+                } else {
+                    new_map.insert(address, (store.old_value, store.new_value, store.old_value));
+                }
             }
         }
 
@@ -544,8 +651,11 @@ impl<'f> Context<'f> {
         }
 
         let then_condition = then_branch.condition;
-        let else_condition = else_branch.condition;
-
+        let else_condition = if let Some(branch) = else_branch {
+            branch.condition
+        } else {
+            self.inserter.function.dfg.make_constant(FieldElement::zero(), Type::bool())
+        };
         let block = self.inserter.function.entry_block();
 
         let mut value_merger =
@@ -607,35 +717,6 @@ impl<'f> Context<'f> {
         }
     }
 
-    /// Inline all instructions from the given destination block into the entry block.
-    /// Afterwards, check the block's terminator and continue inlining recursively.
-    ///
-    /// Returns the final block that was inlined.
-    ///
-    /// Expects that the `arguments` given are already translated via self.inserter.resolve.
-    /// If they are not, it is possible some values which no longer exist, such as block
-    /// parameters, will be kept in the program.
-    fn inline_block(&mut self, destination: BasicBlockId, arguments: &[ValueId]) -> BasicBlockId {
-        self.inserter.remember_block_params(destination, arguments);
-
-        // If this is not a separate variable, clippy gets confused and says the to_vec is
-        // unnecessary, when removing it actually causes an aliasing/mutability error.
-        let instructions = self.inserter.function.dfg[destination].instructions().to_vec();
-
-        for instruction in instructions.iter() {
-            let results = self.push_instruction(*instruction);
-            let (instruction, _) = self.inserter.map_instruction(*instruction);
-            let mut capacity_tracker = SliceCapacityTracker::new(&self.inserter.function.dfg);
-            capacity_tracker.collect_slice_information(
-                &instruction,
-                &mut self.slice_sizes,
-                results,
-            );
-        }
-
-        self.handle_terminator(destination)
-    }
-
     /// Push the given instruction to the end of the entry block of the current function.
     ///
     /// Note that each ValueId of the instruction will be mapped via self.inserter.resolve.
@@ -666,7 +747,7 @@ impl<'f> Context<'f> {
         instruction: Instruction,
         call_stack: CallStack,
     ) -> Instruction {
-        if let Some((_, condition)) = self.conditions.last().copied() {
+        if let Some(condition) = self.get_last_condition() {
             match instruction {
                 Instruction::Constrain(lhs, rhs, message) => {
                     // Replace constraint `lhs == rhs` with `condition * lhs == condition * rhs`.
@@ -741,8 +822,8 @@ impl<'f> Context<'f> {
         }
     }
 
-    fn undo_stores_in_then_branch(&mut self, then_branch: &Branch) {
-        for (address, store) in &then_branch.store_values {
+    fn undo_stores_in_then_branch(&mut self, store_values: &HashMap<ValueId, Store>) {
+        for (address, store) in store_values {
             let address = *address;
             let value = store.old_value;
             self.insert_instruction_with_typevars(Instruction::Store { address, value }, None);
diff --git a/compiler/noirc_frontend/src/ast/statement.rs b/compiler/noirc_frontend/src/ast/statement.rs
index f39b71405d3..387840b57c4 100644
--- a/compiler/noirc_frontend/src/ast/statement.rs
+++ b/compiler/noirc_frontend/src/ast/statement.rs
@@ -240,6 +240,17 @@ pub trait Recoverable {
     fn error(span: Span) -> Self;
 }
 
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub struct ModuleDeclaration {
+    pub ident: Ident,
+}
+
+impl std::fmt::Display for ModuleDeclaration {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "mod {}", self.ident)
+    }
+}
+
 #[derive(Debug, PartialEq, Eq, Clone)]
 pub struct ImportStatement {
     pub path: Path,
diff --git a/compiler/noirc_frontend/src/debug/mod.rs b/compiler/noirc_frontend/src/debug/mod.rs
index a88567fcaf9..05916502d73 100644
--- a/compiler/noirc_frontend/src/debug/mod.rs
+++ b/compiler/noirc_frontend/src/debug/mod.rs
@@ -4,9 +4,11 @@ use crate::{
     ast::{Path, PathKind},
     parser::{Item, ItemKind},
 };
+use noirc_errors::debug_info::{DebugFnId, DebugFunction};
 use noirc_errors::{Span, Spanned};
 use std::collections::HashMap;
 use std::collections::VecDeque;
+use std::mem::take;
 
 const MAX_MEMBER_ASSIGN_DEPTH: usize = 8;
 
@@ -26,8 +28,12 @@ pub struct DebugInstrumenter {
     // all field names referenced when assigning to a member of a variable
     pub field_names: HashMap<SourceFieldId, String>,
 
+    // all collected function metadata (name + argument names)
+    pub functions: HashMap<DebugFnId, DebugFunction>,
+
     next_var_id: u32,
     next_field_name_id: u32,
+    next_fn_id: u32,
 
     // last seen variable names and their IDs grouped by scope
     scope: Vec<HashMap<String, SourceVarId>>,
@@ -38,9 +44,11 @@ impl Default for DebugInstrumenter {
         Self {
             variables: HashMap::default(),
             field_names: HashMap::default(),
+            functions: HashMap::default(),
             scope: vec![],
             next_var_id: 0,
             next_field_name_id: 1,
+            next_fn_id: 0,
         }
     }
 }
@@ -76,10 +84,22 @@ impl DebugInstrumenter {
         field_name_id
     }
 
+    fn insert_function(&mut self, fn_name: String, arguments: Vec<String>) -> DebugFnId {
+        let fn_id = DebugFnId(self.next_fn_id);
+        self.next_fn_id += 1;
+        self.functions.insert(fn_id, DebugFunction { name: fn_name, arg_names: arguments });
+        fn_id
+    }
+
     fn walk_fn(&mut self, func: &mut ast::FunctionDefinition) {
+        let func_name = func.name.0.contents.clone();
+        let func_args =
+            func.parameters.iter().map(|param| pattern_to_string(&param.pattern)).collect();
+        let fn_id = self.insert_function(func_name, func_args);
+        let enter_stmt = build_debug_call_stmt("enter", fn_id, func.span);
         self.scope.push(HashMap::default());
 
-        let set_fn_params = func
+        let set_fn_params: Vec<_> = func
             .parameters
             .iter()
             .flat_map(|param| {
@@ -93,10 +113,21 @@ impl DebugInstrumenter {
             })
             .collect();
 
-        self.walk_scope(&mut func.body.0, func.span);
+        let func_body = &mut func.body.0;
+        let mut statements = take(func_body);
+
+        self.walk_scope(&mut statements, func.span);
 
-        // prepend fn params:
-        func.body.0 = [set_fn_params, func.body.0.clone()].concat();
+        // walk_scope ensures that the last statement is the return value of the function
+        let last_stmt = statements.pop().expect("at least one statement after walk_scope");
+        let exit_stmt = build_debug_call_stmt("exit", fn_id, last_stmt.span);
+
+        // rebuild function body
+        func_body.push(enter_stmt);
+        func_body.extend(set_fn_params);
+        func_body.extend(statements);
+        func_body.push(exit_stmt);
+        func_body.push(last_stmt);
     }
 
     // Modify a vector of statements in-place, adding instrumentation for sets and drops.
@@ -427,6 +458,8 @@ impl DebugInstrumenter {
             use dep::__debug::{{
                 __debug_var_assign,
                 __debug_var_drop,
+                __debug_fn_enter,
+                __debug_fn_exit,
                 __debug_dereference_assign,
                 {member_assigns},
             }};"#
@@ -451,14 +484,32 @@ pub fn build_debug_crate_file() -> String {
             }
 
             #[oracle(__debug_var_drop)]
-            unconstrained fn __debug_var_drop_oracle<T>(_var_id: u32) {}
-            unconstrained fn __debug_var_drop_inner<T>(var_id: u32) {
+            unconstrained fn __debug_var_drop_oracle(_var_id: u32) {}
+            unconstrained fn __debug_var_drop_inner(var_id: u32) {
                 __debug_var_drop_oracle(var_id);
             }
-            pub fn __debug_var_drop<T>(var_id: u32) {
+            pub fn __debug_var_drop(var_id: u32) {
                 __debug_var_drop_inner(var_id);
             }
 
+            #[oracle(__debug_fn_enter)]
+            unconstrained fn __debug_fn_enter_oracle(_fn_id: u32) {}
+            unconstrained fn __debug_fn_enter_inner(fn_id: u32) {
+                __debug_fn_enter_oracle(fn_id);
+            }
+            pub fn __debug_fn_enter(fn_id: u32) {
+                __debug_fn_enter_inner(fn_id);
+            }
+
+            #[oracle(__debug_fn_exit)]
+            unconstrained fn __debug_fn_exit_oracle(_fn_id: u32) {}
+            unconstrained fn __debug_fn_exit_inner(fn_id: u32) {
+                __debug_fn_exit_oracle(fn_id);
+            }
+            pub fn __debug_fn_exit(fn_id: u32) {
+                __debug_fn_exit_inner(fn_id);
+            }
+
             #[oracle(__debug_dereference_assign)]
             unconstrained fn __debug_dereference_assign_oracle<T>(_var_id: u32, _value: T) {}
             unconstrained fn __debug_dereference_assign_inner<T>(var_id: u32, value: T) {
@@ -561,6 +612,21 @@ fn build_assign_member_stmt(
     ast::Statement { kind: ast::StatementKind::Semi(ast::Expression { kind, span }), span }
 }
 
+fn build_debug_call_stmt(fname: &str, fn_id: DebugFnId, span: Span) -> ast::Statement {
+    let kind = ast::ExpressionKind::Call(Box::new(ast::CallExpression {
+        func: Box::new(ast::Expression {
+            kind: ast::ExpressionKind::Variable(ast::Path {
+                segments: vec![ident(&format!["__debug_fn_{fname}"], span)],
+                kind: PathKind::Plain,
+                span,
+            }),
+            span,
+        }),
+        arguments: vec![uint_expr(fn_id.0 as u128, span)],
+    }));
+    ast::Statement { kind: ast::StatementKind::Semi(ast::Expression { kind, span }), span }
+}
+
 fn pattern_vars(pattern: &ast::Pattern) -> Vec<(ast::Ident, bool)> {
     let mut vars = vec![];
     let mut stack = VecDeque::from([(pattern, false)]);
@@ -585,6 +651,30 @@ fn pattern_vars(pattern: &ast::Pattern) -> Vec<(ast::Ident, bool)> {
     vars
 }
 
+fn pattern_to_string(pattern: &ast::Pattern) -> String {
+    match pattern {
+        ast::Pattern::Identifier(id) => id.0.contents.clone(),
+        ast::Pattern::Mutable(mpat, _, _) => format!("mut {}", pattern_to_string(mpat.as_ref())),
+        ast::Pattern::Tuple(elements, _) => format!(
+            "({})",
+            elements.iter().map(pattern_to_string).collect::<Vec<String>>().join(", ")
+        ),
+        ast::Pattern::Struct(name, fields, _) => {
+            format!(
+                "{} {{ {} }}",
+                name,
+                fields
+                    .iter()
+                    .map(|(field_ident, field_pattern)| {
+                        format!("{}: {}", &field_ident.0.contents, pattern_to_string(field_pattern))
+                    })
+                    .collect::<Vec<_>>()
+                    .join(", "),
+            )
+        }
+    }
+}
+
 fn ident(s: &str, span: Span) -> ast::Ident {
     ast::Ident(Spanned::from(span, s.to_string()))
 }
diff --git a/compiler/noirc_frontend/src/hir/def_collector/dc_crate.rs b/compiler/noirc_frontend/src/hir/def_collector/dc_crate.rs
index 7f36af5b30e..27b1d376f11 100644
--- a/compiler/noirc_frontend/src/hir/def_collector/dc_crate.rs
+++ b/compiler/noirc_frontend/src/hir/def_collector/dc_crate.rs
@@ -207,7 +207,7 @@ impl DefCollector {
         context: &mut Context,
         ast: SortedModule,
         root_file_id: FileId,
-        macro_processors: Vec<&dyn MacroProcessor>,
+        macro_processors: &[&dyn MacroProcessor],
     ) -> Vec<(CompilationError, FileId)> {
         let mut errors: Vec<(CompilationError, FileId)> = vec![];
         let crate_id = def_map.krate;
@@ -220,11 +220,7 @@ impl DefCollector {
         let crate_graph = &context.crate_graph[crate_id];
 
         for dep in crate_graph.dependencies.clone() {
-            errors.extend(CrateDefMap::collect_defs(
-                dep.crate_id,
-                context,
-                macro_processors.clone(),
-            ));
+            errors.extend(CrateDefMap::collect_defs(dep.crate_id, context, macro_processors));
 
             let dep_def_root =
                 context.def_map(&dep.crate_id).expect("ice: def map was just created").root;
@@ -257,7 +253,7 @@ impl DefCollector {
         context.def_maps.insert(crate_id, def_collector.def_map);
 
         // TODO(#4653): generalize this function
-        for macro_processor in &macro_processors {
+        for macro_processor in macro_processors {
             macro_processor
                 .process_unresolved_traits_impls(
                     &crate_id,
@@ -282,7 +278,7 @@ impl DefCollector {
 
         // Resolve unresolved imports collected from the crate, one by one.
         for collected_import in def_collector.collected_imports {
-            match resolve_import(crate_id, collected_import, &context.def_maps) {
+            match resolve_import(crate_id, &collected_import, &context.def_maps) {
                 Ok(resolved_import) => {
                     // Populate module namespaces according to the imports used
                     let current_def_map = context.def_maps.get_mut(&crate_id).unwrap();
diff --git a/compiler/noirc_frontend/src/hir/def_collector/dc_mod.rs b/compiler/noirc_frontend/src/hir/def_collector/dc_mod.rs
index fc777ac877b..188b262498d 100644
--- a/compiler/noirc_frontend/src/hir/def_collector/dc_mod.rs
+++ b/compiler/noirc_frontend/src/hir/def_collector/dc_mod.rs
@@ -9,8 +9,8 @@ use crate::{
     hir::def_collector::dc_crate::{UnresolvedStruct, UnresolvedTrait},
     node_interner::{FunctionModifiers, TraitId, TypeAliasId},
     parser::{SortedModule, SortedSubModule},
-    FunctionDefinition, Ident, ItemVisibility, LetStatement, NoirFunction, NoirStruct, NoirTrait,
-    NoirTraitImpl, NoirTypeAlias, TraitImplItem, TraitItem, TypeImpl,
+    FunctionDefinition, Ident, ItemVisibility, LetStatement, ModuleDeclaration, NoirFunction,
+    NoirStruct, NoirTrait, NoirTraitImpl, NoirTypeAlias, TraitImplItem, TraitItem, TypeImpl,
 };
 
 use super::{
@@ -523,15 +523,15 @@ impl<'a> ModCollector<'a> {
     fn parse_module_declaration(
         &mut self,
         context: &mut Context,
-        mod_name: &Ident,
+        mod_decl: &ModuleDeclaration,
         crate_id: CrateId,
     ) -> Vec<(CompilationError, FileId)> {
         let mut errors: Vec<(CompilationError, FileId)> = vec![];
         let child_file_id =
-            match find_module(&context.file_manager, self.file_id, &mod_name.0.contents) {
+            match find_module(&context.file_manager, self.file_id, &mod_decl.ident.0.contents) {
                 Ok(child_file_id) => child_file_id,
                 Err(expected_path) => {
-                    let mod_name = mod_name.clone();
+                    let mod_name = mod_decl.ident.clone();
                     let err =
                         DefCollectorErrorKind::UnresolvedModuleDecl { mod_name, expected_path };
                     errors.push((err.into(), self.file_id));
@@ -539,17 +539,17 @@ impl<'a> ModCollector<'a> {
                 }
             };
 
-        let location = Location { file: self.file_id, span: mod_name.span() };
+        let location = Location { file: self.file_id, span: mod_decl.ident.span() };
 
         if let Some(old_location) = context.visited_files.get(&child_file_id) {
             let error = DefCollectorErrorKind::ModuleAlreadyPartOfCrate {
-                mod_name: mod_name.clone(),
+                mod_name: mod_decl.ident.clone(),
                 span: location.span,
             };
             errors.push((error.into(), location.file));
 
             let error = DefCollectorErrorKind::ModuleOriginallyDefined {
-                mod_name: mod_name.clone(),
+                mod_name: mod_decl.ident.clone(),
                 span: old_location.span,
             };
             errors.push((error.into(), old_location.file));
@@ -567,7 +567,7 @@ impl<'a> ModCollector<'a> {
         );
 
         // Add module into def collector and get a ModuleId
-        match self.push_child_module(mod_name, child_file_id, true, false) {
+        match self.push_child_module(&mod_decl.ident, child_file_id, true, false) {
             Ok(child_mod_id) => {
                 errors.extend(collect_defs(
                     self.def_collector,
diff --git a/compiler/noirc_frontend/src/hir/def_map/mod.rs b/compiler/noirc_frontend/src/hir/def_map/mod.rs
index 8721bdb6c3c..1326ffca9f7 100644
--- a/compiler/noirc_frontend/src/hir/def_map/mod.rs
+++ b/compiler/noirc_frontend/src/hir/def_map/mod.rs
@@ -73,7 +73,7 @@ impl CrateDefMap {
     pub fn collect_defs(
         crate_id: CrateId,
         context: &mut Context,
-        macro_processors: Vec<&dyn MacroProcessor>,
+        macro_processors: &[&dyn MacroProcessor],
     ) -> Vec<(CompilationError, FileId)> {
         // Check if this Crate has already been compiled
         // XXX: There is probably a better alternative for this.
@@ -90,7 +90,7 @@ impl CrateDefMap {
         let (ast, parsing_errors) = context.parsed_file_results(root_file_id);
         let mut ast = ast.into_sorted();
 
-        for macro_processor in &macro_processors {
+        for macro_processor in macro_processors {
             match macro_processor.process_untyped_ast(ast.clone(), &crate_id, context) {
                 Ok(processed_ast) => {
                     ast = processed_ast;
@@ -115,13 +115,7 @@ impl CrateDefMap {
         };
 
         // Now we want to populate the CrateDefMap using the DefCollector
-        errors.extend(DefCollector::collect(
-            def_map,
-            context,
-            ast,
-            root_file_id,
-            macro_processors.clone(),
-        ));
+        errors.extend(DefCollector::collect(def_map, context, ast, root_file_id, macro_processors));
 
         errors.extend(
             parsing_errors.iter().map(|e| (e.clone().into(), root_file_id)).collect::<Vec<_>>(),
diff --git a/compiler/noirc_frontend/src/hir/resolution/errors.rs b/compiler/noirc_frontend/src/hir/resolution/errors.rs
index d2fe67da38c..1049599f079 100644
--- a/compiler/noirc_frontend/src/hir/resolution/errors.rs
+++ b/compiler/noirc_frontend/src/hir/resolution/errors.rs
@@ -80,8 +80,6 @@ pub enum ResolverError {
     PrivateFunctionCalled { name: String, span: Span },
     #[error("{name} is not visible from the current crate")]
     NonCrateFunctionCalled { name: String, span: Span },
-    #[error("Only sized types may be used in the entry point to a program")]
-    InvalidTypeForEntryPoint { span: Span },
     #[error("Nested slices are not supported")]
     NestedSlices { span: Span },
     #[error("#[recursive] attribute is only allowed on entry points to a program")]
@@ -309,9 +307,6 @@ impl From<ResolverError> for Diagnostic {
             ResolverError::NonCrateFunctionCalled { span, name } => Diagnostic::simple_warning(
                     format!("{name} is not visible from the current crate"),
                     format!("{name} is only visible within its crate"), span),
-            ResolverError::InvalidTypeForEntryPoint { span } => Diagnostic::simple_error(
-                "Only sized types may be used in the entry point to a program".to_string(),
-                "Slices, references, or any type containing them may not be used in main or a contract function".to_string(), span),
             ResolverError::NestedSlices { span } => Diagnostic::simple_error(
                 "Nested slices are not supported".into(),
                 "Try to use a constant sized array instead".into(),
diff --git a/compiler/noirc_frontend/src/hir/resolution/import.rs b/compiler/noirc_frontend/src/hir/resolution/import.rs
index e6ac33053a0..9c8418daf80 100644
--- a/compiler/noirc_frontend/src/hir/resolution/import.rs
+++ b/compiler/noirc_frontend/src/hir/resolution/import.rs
@@ -52,7 +52,7 @@ impl From<PathResolutionError> for CustomDiagnostic {
 
 pub fn resolve_import(
     crate_id: CrateId,
-    import_directive: ImportDirective,
+    import_directive: &ImportDirective,
     def_maps: &BTreeMap<CrateId, CrateDefMap>,
 ) -> Result<ResolvedImport, (PathResolutionError, LocalModuleId)> {
     let def_map = &def_maps[&crate_id];
@@ -62,10 +62,10 @@ pub fn resolve_import(
 
     let module_scope = import_directive.module_id;
     let resolved_namespace =
-        resolve_path_to_ns(&import_directive, def_map, def_maps, allow_contracts)
+        resolve_path_to_ns(import_directive, def_map, def_maps, allow_contracts)
             .map_err(|error| (error, module_scope))?;
 
-    let name = resolve_path_name(&import_directive);
+    let name = resolve_path_name(import_directive);
     Ok(ResolvedImport {
         name,
         resolved_namespace,
diff --git a/compiler/noirc_frontend/src/hir/resolution/resolver.rs b/compiler/noirc_frontend/src/hir/resolution/resolver.rs
index 48cd44c9d46..069463cfb12 100644
--- a/compiler/noirc_frontend/src/hir/resolution/resolver.rs
+++ b/compiler/noirc_frontend/src/hir/resolution/resolver.rs
@@ -911,10 +911,6 @@ impl<'a> Resolver<'a> {
                 });
             }
 
-            if self.is_entry_point_function(func) {
-                self.verify_type_valid_for_program_input(&typ);
-            }
-
             let pattern = self.resolve_pattern(pattern, DefinitionKind::Local(None));
             let typ = self.resolve_type_inner(typ, &mut generics);
 
@@ -991,6 +987,7 @@ impl<'a> Resolver<'a> {
             return_distinctness: func.def.return_distinctness,
             has_body: !func.def.body.is_empty(),
             trait_constraints: self.resolve_trait_constraints(&func.def.where_clause),
+            is_entry_point: self.is_entry_point_function(func),
         }
     }
 
@@ -2001,89 +1998,6 @@ impl<'a> Resolver<'a> {
         }
         HirLiteral::FmtStr(str, fmt_str_idents)
     }
-
-    /// Only sized types are valid to be used as main's parameters or the parameters to a contract
-    /// function. If the given type is not sized (e.g. contains a slice or NamedGeneric type), an
-    /// error is issued.
-    fn verify_type_valid_for_program_input(&mut self, typ: &UnresolvedType) {
-        match &typ.typ {
-            UnresolvedTypeData::FieldElement
-            | UnresolvedTypeData::Integer(_, _)
-            | UnresolvedTypeData::Bool
-            | UnresolvedTypeData::Unit
-            | UnresolvedTypeData::Error => (),
-
-            UnresolvedTypeData::MutableReference(_)
-            | UnresolvedTypeData::Function(_, _, _)
-            | UnresolvedTypeData::FormatString(_, _)
-            | UnresolvedTypeData::TraitAsType(..)
-            | UnresolvedTypeData::Unspecified => {
-                let span = typ.span.expect("Function parameters should always have spans");
-                self.push_err(ResolverError::InvalidTypeForEntryPoint { span });
-            }
-
-            UnresolvedTypeData::Array(length, element) => {
-                if let Some(length) = length {
-                    self.verify_type_expression_valid_for_program_input(length);
-                } else {
-                    let span = typ.span.expect("Function parameters should always have spans");
-                    self.push_err(ResolverError::InvalidTypeForEntryPoint { span });
-                }
-                self.verify_type_valid_for_program_input(element);
-            }
-            UnresolvedTypeData::Expression(expression) => {
-                self.verify_type_expression_valid_for_program_input(expression);
-            }
-            UnresolvedTypeData::String(length) => {
-                if let Some(length) = length {
-                    self.verify_type_expression_valid_for_program_input(length);
-                } else {
-                    let span = typ.span.expect("Function parameters should always have spans");
-                    self.push_err(ResolverError::InvalidTypeForEntryPoint { span });
-                }
-            }
-            UnresolvedTypeData::Named(path, generics, _) => {
-                // Since the type is named, we need to resolve it to see what it actually refers to
-                // in order to check whether it is valid. Since resolving it may lead to a
-                // resolution error, we have to truncate our error count to the previous count just
-                // in case. This is to ensure resolution errors are not issued twice when this type
-                // is later resolved properly.
-                let error_count = self.errors.len();
-                let resolved = self.resolve_named_type(path.clone(), generics.clone(), &mut vec![]);
-                self.errors.truncate(error_count);
-
-                if !resolved.is_valid_for_program_input() {
-                    let span = typ.span.expect("Function parameters should always have spans");
-                    self.push_err(ResolverError::InvalidTypeForEntryPoint { span });
-                }
-            }
-            UnresolvedTypeData::Tuple(elements) => {
-                for element in elements {
-                    self.verify_type_valid_for_program_input(element);
-                }
-            }
-            UnresolvedTypeData::Parenthesized(typ) => self.verify_type_valid_for_program_input(typ),
-        }
-    }
-
-    fn verify_type_expression_valid_for_program_input(&mut self, expr: &UnresolvedTypeExpression) {
-        match expr {
-            UnresolvedTypeExpression::Constant(_, _) => (),
-            UnresolvedTypeExpression::Variable(path) => {
-                let error_count = self.errors.len();
-                let resolved = self.resolve_named_type(path.clone(), vec![], &mut vec![]);
-                self.errors.truncate(error_count);
-
-                if !resolved.is_valid_for_program_input() {
-                    self.push_err(ResolverError::InvalidTypeForEntryPoint { span: path.span() });
-                }
-            }
-            UnresolvedTypeExpression::BinaryOperation(lhs, _, rhs, _) => {
-                self.verify_type_expression_valid_for_program_input(lhs);
-                self.verify_type_expression_valid_for_program_input(rhs);
-            }
-        }
-    }
 }
 
 /// Gives an error if a user tries to create a mutable reference
diff --git a/compiler/noirc_frontend/src/hir/type_check/errors.rs b/compiler/noirc_frontend/src/hir/type_check/errors.rs
index 96d30100d8b..cba2400441f 100644
--- a/compiler/noirc_frontend/src/hir/type_check/errors.rs
+++ b/compiler/noirc_frontend/src/hir/type_check/errors.rs
@@ -122,6 +122,8 @@ pub enum TypeCheckError {
     ConstrainedReferenceToUnconstrained { span: Span },
     #[error("Slices cannot be returned from an unconstrained runtime to a constrained runtime")]
     UnconstrainedSliceReturnToConstrained { span: Span },
+    #[error("Only sized types may be used in the entry point to a program")]
+    InvalidTypeForEntryPoint { span: Span },
 }
 
 impl TypeCheckError {
@@ -284,6 +286,9 @@ impl From<TypeCheckError> for Diagnostic {
                 let msg = format!("Constraint for `{typ}: {trait_name}` is not needed, another matching impl is already in scope");
                 Diagnostic::simple_warning(msg, "Unnecessary trait constraint in where clause".into(), span)
             }
+            TypeCheckError::InvalidTypeForEntryPoint { span } => Diagnostic::simple_error(
+                "Only sized types may be used in the entry point to a program".to_string(),
+                "Slices, references, or any type containing them may not be used in main or a contract function".to_string(), span),
         }
     }
 }
diff --git a/compiler/noirc_frontend/src/hir/type_check/expr.rs b/compiler/noirc_frontend/src/hir/type_check/expr.rs
index 7b854e58fca..c5287d35caf 100644
--- a/compiler/noirc_frontend/src/hir/type_check/expr.rs
+++ b/compiler/noirc_frontend/src/hir/type_check/expr.rs
@@ -863,7 +863,13 @@ impl<'interner> TypeChecker<'interner> {
                     span: op.location.span,
                 });
 
-                self.comparator_operand_type_rules(x_type, y_type, op, span)
+                let (_, use_impl) = self.comparator_operand_type_rules(x_type, y_type, op, span)?;
+
+                // If the size is not constant, we must fall back to a user-provided impl for
+                // equality on slices.
+                let size = x_size.follow_bindings();
+                let use_impl = use_impl || size.evaluate_to_u64().is_none();
+                Ok((Bool, use_impl))
             }
 
             (String(x_size), String(y_size)) => {
diff --git a/compiler/noirc_frontend/src/hir/type_check/mod.rs b/compiler/noirc_frontend/src/hir/type_check/mod.rs
index 21d1c75a0f2..aab793ec867 100644
--- a/compiler/noirc_frontend/src/hir/type_check/mod.rs
+++ b/compiler/noirc_frontend/src/hir/type_check/mod.rs
@@ -14,7 +14,7 @@ mod stmt;
 pub use errors::TypeCheckError;
 
 use crate::{
-    hir_def::{expr::HirExpression, stmt::HirStatement, traits::TraitConstraint},
+    hir_def::{expr::HirExpression, function::Param, stmt::HirStatement, traits::TraitConstraint},
     node_interner::{ExprId, FuncId, GlobalId, NodeInterner},
     Type,
 };
@@ -74,6 +74,7 @@ pub fn type_check_func(interner: &mut NodeInterner, func_id: FuncId) -> Vec<Type
     // This is locally obvious, but it must be bound here so that the
     // Definition object of the parameter in the NodeInterner is given the correct type.
     for param in parameters {
+        check_if_type_is_valid_for_program_input(&type_checker, func_id, &param, &mut errors);
         type_checker.bind_pattern(&param.0, param.1);
     }
 
@@ -143,6 +144,22 @@ pub fn type_check_func(interner: &mut NodeInterner, func_id: FuncId) -> Vec<Type
     errors
 }
 
+/// Only sized types are valid to be used as main's parameters or the parameters to a contract
+/// function. If the given type is not sized (e.g. contains a slice or NamedGeneric type), an
+/// error is issued.
+fn check_if_type_is_valid_for_program_input(
+    type_checker: &TypeChecker<'_>,
+    func_id: FuncId,
+    param: &Param,
+    errors: &mut Vec<TypeCheckError>,
+) {
+    let meta = type_checker.interner.function_meta(&func_id);
+    if meta.is_entry_point && !param.1.is_valid_for_program_input() {
+        let span = param.0.span();
+        errors.push(TypeCheckError::InvalidTypeForEntryPoint { span });
+    }
+}
+
 fn function_info(interner: &NodeInterner, function_body_id: &ExprId) -> (noirc_errors::Span, bool) {
     let (expr_span, empty_function) =
         if let HirExpression::Block(block) = interner.expression(function_body_id) {
@@ -329,6 +346,7 @@ mod test {
             trait_impl: None,
             return_type: FunctionReturnType::Default(Span::default()),
             trait_constraints: Vec::new(),
+            is_entry_point: true,
         };
         interner.push_fn_meta(func_meta, func_id);
 
diff --git a/compiler/noirc_frontend/src/hir_def/function.rs b/compiler/noirc_frontend/src/hir_def/function.rs
index d3ab2a9393b..82bbe1aa5b6 100644
--- a/compiler/noirc_frontend/src/hir_def/function.rs
+++ b/compiler/noirc_frontend/src/hir_def/function.rs
@@ -112,6 +112,10 @@ pub struct FuncMeta {
 
     /// The trait impl this function belongs to, if any
     pub trait_impl: Option<TraitImplId>,
+
+    /// True if this function is an entry point to the program.
+    /// For non-contracts, this means the function is `main`.
+    pub is_entry_point: bool,
 }
 
 impl FuncMeta {
diff --git a/compiler/noirc_frontend/src/hir_def/types.rs b/compiler/noirc_frontend/src/hir_def/types.rs
index b70aa43701c..5ab036eef5b 100644
--- a/compiler/noirc_frontend/src/hir_def/types.rs
+++ b/compiler/noirc_frontend/src/hir_def/types.rs
@@ -703,10 +703,10 @@ impl Type {
             | Type::TraitAsType(..)
             | Type::NotConstant => false,
 
-            // This function is called during name resolution before we've verified aliases
-            // are not cyclic. As a result, it wouldn't be safe to check this alias' definition
-            // to see if the aliased type is valid.
-            Type::Alias(..) => false,
+            Type::Alias(alias, generics) => {
+                let alias = alias.borrow();
+                alias.get_type(generics).is_valid_for_program_input()
+            }
 
             Type::Array(length, element) => {
                 length.is_valid_for_program_input() && element.is_valid_for_program_input()
@@ -1768,9 +1768,11 @@ impl From<&Type> for PrintableType {
             Type::TypeVariable(_, _) => unreachable!(),
             Type::NamedGeneric(..) => unreachable!(),
             Type::Forall(..) => unreachable!(),
-            Type::Function(_, _, env) => {
-                PrintableType::Function { env: Box::new(env.as_ref().into()) }
-            }
+            Type::Function(arguments, return_type, env) => PrintableType::Function {
+                arguments: arguments.iter().map(|arg| arg.into()).collect(),
+                return_type: Box::new(return_type.as_ref().into()),
+                env: Box::new(env.as_ref().into()),
+            },
             Type::MutableReference(typ) => {
                 PrintableType::MutableReference { typ: Box::new(typ.as_ref().into()) }
             }
diff --git a/compiler/noirc_frontend/src/monomorphization/ast.rs b/compiler/noirc_frontend/src/monomorphization/ast.rs
index e4e619d5d92..7fcf8e87792 100644
--- a/compiler/noirc_frontend/src/monomorphization/ast.rs
+++ b/compiler/noirc_frontend/src/monomorphization/ast.rs
@@ -1,7 +1,7 @@
 use acvm::FieldElement;
 use iter_extended::vecmap;
 use noirc_errors::{
-    debug_info::{DebugTypes, DebugVariables},
+    debug_info::{DebugFunctions, DebugTypes, DebugVariables},
     Location,
 };
 
@@ -253,6 +253,7 @@ pub struct Program {
     /// Indicates to a backend whether a SNARK-friendly prover should be used.  
     pub recursive: bool,
     pub debug_variables: DebugVariables,
+    pub debug_functions: DebugFunctions,
     pub debug_types: DebugTypes,
 }
 
@@ -266,6 +267,7 @@ impl Program {
         return_visibility: Visibility,
         recursive: bool,
         debug_variables: DebugVariables,
+        debug_functions: DebugFunctions,
         debug_types: DebugTypes,
     ) -> Program {
         Program {
@@ -276,6 +278,7 @@ impl Program {
             return_visibility,
             recursive,
             debug_variables,
+            debug_functions,
             debug_types,
         }
     }
diff --git a/compiler/noirc_frontend/src/monomorphization/debug.rs b/compiler/noirc_frontend/src/monomorphization/debug.rs
index a8ff4399f99..cf4e0ab792e 100644
--- a/compiler/noirc_frontend/src/monomorphization/debug.rs
+++ b/compiler/noirc_frontend/src/monomorphization/debug.rs
@@ -76,7 +76,7 @@ impl<'interner> Monomorphizer<'interner> {
         let var_type = self.interner.id_type(call.arguments[DEBUG_VALUE_ARG_SLOT]);
         let source_var_id = source_var_id.to_u128().into();
         // then update the ID used for tracking at runtime
-        let var_id = self.debug_type_tracker.insert_var(source_var_id, var_type);
+        let var_id = self.debug_type_tracker.insert_var(source_var_id, &var_type);
         let interned_var_id = self.intern_var_id(var_id, &call.location);
         arguments[DEBUG_VAR_ID_ARG_SLOT] = self.expr(interned_var_id)?;
         Ok(())
diff --git a/compiler/noirc_frontend/src/monomorphization/debug_types.rs b/compiler/noirc_frontend/src/monomorphization/debug_types.rs
index fea073d394f..16b82d1e7b9 100644
--- a/compiler/noirc_frontend/src/monomorphization/debug_types.rs
+++ b/compiler/noirc_frontend/src/monomorphization/debug_types.rs
@@ -3,7 +3,8 @@ use crate::{
     hir_def::types::Type,
 };
 use noirc_errors::debug_info::{
-    DebugTypeId, DebugTypes, DebugVarId, DebugVariable, DebugVariables,
+    DebugFnId, DebugFunction, DebugFunctions, DebugTypeId, DebugTypes, DebugVarId, DebugVariable,
+    DebugVariables,
 };
 use noirc_printable_type::PrintableType;
 use std::collections::HashMap;
@@ -30,7 +31,10 @@ pub struct DebugTypeTracker {
     // All instances of tracked variables
     variables: HashMap<DebugVarId, (SourceVarId, DebugTypeId)>,
 
-    // Types of tracked variables
+    // Function metadata collected during instrumentation injection
+    functions: HashMap<DebugFnId, DebugFunction>,
+
+    // Types of tracked variables and functions
     types: HashMap<DebugTypeId, PrintableType>,
     types_reverse: HashMap<PrintableType, DebugTypeId>,
 
@@ -43,34 +47,29 @@ impl DebugTypeTracker {
         DebugTypeTracker {
             source_variables: instrumenter.variables.clone(),
             source_field_names: instrumenter.field_names.clone(),
+            functions: instrumenter.functions.clone(),
             ..DebugTypeTracker::default()
         }
     }
 
-    pub fn extract_vars_and_types(&self) -> (DebugVariables, DebugTypes) {
+    pub fn extract_vars_and_types(&self) -> (DebugVariables, DebugFunctions, DebugTypes) {
         let debug_variables = self
             .variables
             .clone()
             .into_iter()
             .map(|(var_id, (source_var_id, type_id))| {
-                (
-                    var_id,
-                    DebugVariable {
-                        name: self.source_variables.get(&source_var_id).cloned().unwrap_or_else(
-                            || {
-                                unreachable!(
-                                    "failed to retrieve variable name for {source_var_id:?}"
-                                );
-                            },
-                        ),
-                        debug_type_id: type_id,
-                    },
-                )
+                let var_name =
+                    self.source_variables.get(&source_var_id).cloned().unwrap_or_else(|| {
+                        unreachable!("failed to retrieve variable name for {source_var_id:?}");
+                    });
+                (var_id, DebugVariable { name: var_name, debug_type_id: type_id })
             })
             .collect();
+
+        let debug_functions = self.functions.clone().into_iter().collect();
         let debug_types = self.types.clone().into_iter().collect();
 
-        (debug_variables, debug_types)
+        (debug_variables, debug_functions, debug_types)
     }
 
     pub fn resolve_field_index(
@@ -83,19 +82,24 @@ impl DebugTypeTracker {
             .and_then(|field_name| get_field(cursor_type, field_name))
     }
 
-    pub fn insert_var(&mut self, source_var_id: SourceVarId, var_type: Type) -> DebugVarId {
-        if !self.source_variables.contains_key(&source_var_id) {
-            unreachable!("cannot find source debug variable {source_var_id:?}");
-        }
-
-        let ptype: PrintableType = var_type.follow_bindings().into();
-        let type_id = self.types_reverse.get(&ptype).copied().unwrap_or_else(|| {
+    fn insert_type(&mut self, the_type: &Type) -> DebugTypeId {
+        let ptype: PrintableType = the_type.follow_bindings().into();
+        self.types_reverse.get(&ptype).copied().unwrap_or_else(|| {
             let type_id = DebugTypeId(self.next_type_id);
             self.next_type_id += 1;
             self.types_reverse.insert(ptype.clone(), type_id);
             self.types.insert(type_id, ptype);
             type_id
-        });
+        })
+    }
+
+    pub fn insert_var(&mut self, source_var_id: SourceVarId, var_type: &Type) -> DebugVarId {
+        if !self.source_variables.contains_key(&source_var_id) {
+            unreachable!("cannot find source debug variable {source_var_id:?}");
+        }
+
+        let type_id = self.insert_type(var_type);
+
         // check if we need to instantiate the var with a new type
         let existing_var_id = self.source_to_debug_vars.get(&source_var_id).and_then(|var_id| {
             let (_, existing_type_id) = self.variables.get(var_id).unwrap();
diff --git a/compiler/noirc_frontend/src/monomorphization/mod.rs b/compiler/noirc_frontend/src/monomorphization/mod.rs
index ce880401d77..cfd9a61d13f 100644
--- a/compiler/noirc_frontend/src/monomorphization/mod.rs
+++ b/compiler/noirc_frontend/src/monomorphization/mod.rs
@@ -165,7 +165,8 @@ pub fn monomorphize_debug(
     let FuncMeta { return_distinctness, return_visibility, kind, .. } =
         monomorphizer.interner.function_meta(&main);
 
-    let (debug_variables, debug_types) = monomorphizer.debug_type_tracker.extract_vars_and_types();
+    let (debug_variables, debug_functions, debug_types) =
+        monomorphizer.debug_type_tracker.extract_vars_and_types();
     let program = Program::new(
         functions,
         function_sig,
@@ -174,6 +175,7 @@ pub fn monomorphize_debug(
         *return_visibility,
         *kind == FunctionKind::Recursive,
         debug_variables,
+        debug_functions,
         debug_types,
     );
     Ok(program)
diff --git a/compiler/noirc_frontend/src/parser/mod.rs b/compiler/noirc_frontend/src/parser/mod.rs
index 0ff7819c00f..ea96dee8a47 100644
--- a/compiler/noirc_frontend/src/parser/mod.rs
+++ b/compiler/noirc_frontend/src/parser/mod.rs
@@ -14,8 +14,8 @@ mod parser;
 use crate::token::{Keyword, Token};
 use crate::{ast::ImportStatement, Expression, NoirStruct};
 use crate::{
-    Ident, LetStatement, NoirFunction, NoirTrait, NoirTraitImpl, NoirTypeAlias, Recoverable,
-    StatementKind, TypeImpl, UseTree,
+    Ident, LetStatement, ModuleDeclaration, NoirFunction, NoirTrait, NoirTraitImpl, NoirTypeAlias,
+    Recoverable, StatementKind, TypeImpl, UseTree,
 };
 
 use chumsky::prelude::*;
@@ -28,7 +28,7 @@ pub use parser::parse_program;
 #[derive(Debug, Clone)]
 pub(crate) enum TopLevelStatement {
     Function(NoirFunction),
-    Module(Ident),
+    Module(ModuleDeclaration),
     Import(UseTree),
     Struct(NoirStruct),
     Trait(NoirTrait),
@@ -220,7 +220,7 @@ pub struct SortedModule {
     pub globals: Vec<LetStatement>,
 
     /// Module declarations like `mod foo;`
-    pub module_decls: Vec<Ident>,
+    pub module_decls: Vec<ModuleDeclaration>,
 
     /// Full submodules as in `mod foo { ... definitions ... }`
     pub submodules: Vec<SortedSubModule>,
@@ -229,7 +229,7 @@ pub struct SortedModule {
 impl std::fmt::Display for SortedModule {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         for decl in &self.module_decls {
-            writeln!(f, "mod {decl};")?;
+            writeln!(f, "{decl};")?;
         }
 
         for import in &self.imports {
@@ -309,7 +309,7 @@ pub enum ItemKind {
     Impl(TypeImpl),
     TypeAlias(NoirTypeAlias),
     Global(LetStatement),
-    ModuleDecl(Ident),
+    ModuleDecl(ModuleDeclaration),
     Submodules(ParsedSubModule),
 }
 
@@ -380,8 +380,8 @@ impl SortedModule {
         self.imports.extend(import_stmt.desugar(None));
     }
 
-    fn push_module_decl(&mut self, mod_name: Ident) {
-        self.module_decls.push(mod_name);
+    fn push_module_decl(&mut self, mod_decl: ModuleDeclaration) {
+        self.module_decls.push(mod_decl);
     }
 
     fn push_submodule(&mut self, submodule: SortedSubModule) {
@@ -474,7 +474,7 @@ impl std::fmt::Display for TopLevelStatement {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
             TopLevelStatement::Function(fun) => fun.fmt(f),
-            TopLevelStatement::Module(m) => write!(f, "mod {m}"),
+            TopLevelStatement::Module(m) => m.fmt(f),
             TopLevelStatement::Import(tree) => write!(f, "use {tree}"),
             TopLevelStatement::Trait(t) => t.fmt(f),
             TopLevelStatement::TraitImpl(i) => i.fmt(f),
diff --git a/compiler/noirc_frontend/src/parser/parser.rs b/compiler/noirc_frontend/src/parser/parser.rs
index 75f4a6359bf..383a1ffafc9 100644
--- a/compiler/noirc_frontend/src/parser/parser.rs
+++ b/compiler/noirc_frontend/src/parser/parser.rs
@@ -40,9 +40,9 @@ use crate::parser::{force, ignore_then_commit, statement_recovery};
 use crate::token::{Keyword, Token, TokenKind};
 use crate::{
     BinaryOp, BinaryOpKind, BlockExpression, Distinctness, ForLoopStatement, ForRange,
-    FunctionReturnType, Ident, IfExpression, InfixExpression, LValue, Literal, NoirTypeAlias,
-    Param, Path, Pattern, Recoverable, Statement, TraitBound, TypeImpl, UnresolvedTraitConstraint,
-    UnresolvedTypeExpression, UseTree, UseTreeKind, Visibility,
+    FunctionReturnType, Ident, IfExpression, InfixExpression, LValue, Literal, ModuleDeclaration,
+    NoirTypeAlias, Param, Path, Pattern, Recoverable, Statement, TraitBound, TypeImpl,
+    UnresolvedTraitConstraint, UnresolvedTypeExpression, UseTree, UseTreeKind, Visibility,
 };
 
 use chumsky::prelude::*;
@@ -370,7 +370,9 @@ fn optional_type_annotation<'a>() -> impl NoirParser<UnresolvedType> + 'a {
 }
 
 fn module_declaration() -> impl NoirParser<TopLevelStatement> {
-    keyword(Keyword::Mod).ignore_then(ident()).map(TopLevelStatement::Module)
+    keyword(Keyword::Mod)
+        .ignore_then(ident())
+        .map(|ident| TopLevelStatement::Module(ModuleDeclaration { ident }))
 }
 
 fn use_statement() -> impl NoirParser<TopLevelStatement> {
diff --git a/compiler/noirc_frontend/src/tests.rs b/compiler/noirc_frontend/src/tests.rs
index c661cc92eef..9be6252b10a 100644
--- a/compiler/noirc_frontend/src/tests.rs
+++ b/compiler/noirc_frontend/src/tests.rs
@@ -81,7 +81,7 @@ mod test {
                 &mut context,
                 program.clone().into_sorted(),
                 root_file_id,
-                Vec::new(), // No macro processors
+                &[], // No macro processors
             ));
         }
         (program, context, errors)
@@ -1206,4 +1206,13 @@ fn lambda$f1(mut env$l1: (Field)) -> Field {
         "#;
         assert_eq!(get_program_errors(src).len(), 1);
     }
+
+    #[test]
+    fn type_aliases_in_entry_point() {
+        let src = r#"
+            type Foo = u8;
+            fn main(_x: Foo) {}
+        "#;
+        assert_eq!(get_program_errors(src).len(), 0);
+    }
 }
diff --git a/compiler/noirc_printable_type/src/lib.rs b/compiler/noirc_printable_type/src/lib.rs
index 24f4f275a14..60f233cd86d 100644
--- a/compiler/noirc_printable_type/src/lib.rs
+++ b/compiler/noirc_printable_type/src/lib.rs
@@ -33,6 +33,8 @@ pub enum PrintableType {
         length: u64,
     },
     Function {
+        arguments: Vec<PrintableType>,
+        return_type: Box<PrintableType>,
         env: Box<PrintableType>,
     },
     MutableReference {
@@ -176,8 +178,8 @@ fn to_string(value: &PrintableValue, typ: &PrintableType) -> Option<String> {
                 output.push_str("false");
             }
         }
-        (PrintableValue::Field(_), PrintableType::Function { .. }) => {
-            output.push_str("<<function>>");
+        (PrintableValue::Field(_), PrintableType::Function { arguments, return_type, .. }) => {
+            output.push_str(&format!("<<fn({:?}) -> {:?}>>", arguments, return_type,));
         }
         (_, PrintableType::MutableReference { .. }) => {
             output.push_str("<<mutable ref>>");
@@ -350,7 +352,7 @@ pub fn decode_value(
 
             PrintableValue::Struct(struct_map)
         }
-        PrintableType::Function { env } => {
+        PrintableType::Function { env, .. } => {
             let field_element = field_iterator.next().unwrap();
             let func_ref = PrintableValue::Field(field_element);
             // we want to consume the fields from the environment, but for now they are not actually printed
diff --git a/compiler/wasm/src/noir/package.ts b/compiler/wasm/src/noir/package.ts
index 81178e6ae96..2856798273a 100644
--- a/compiler/wasm/src/noir/package.ts
+++ b/compiler/wasm/src/noir/package.ts
@@ -105,7 +105,12 @@ export class Package {
       handles
         .filter((handle) => SOURCE_EXTENSIONS.find((ext) => handle.endsWith(ext)))
         .map(async (file) => {
-          const suffix = file.replace(this.#srcPath, '');
+          // Github deps are directly added to the file manager, which causes them to be missing the absolute path to the source file
+          // and only include the extraction directory relative to the fm root directory
+          // This regexp ensures we remove the "real" source path for all dependencies, providing the compiler with what it expects for each source file:
+          // <absoluteSourcePath> -> <sourceAsString> for bin/contract packages
+          // <depAlias/relativePathToSource> -> <sourceAsString> for libs
+          const suffix = file.replace(new RegExp(`.*${this.#srcPath}`), '');
           return {
             path: this.getType() === 'lib' ? `${alias ? alias : this.#config.package.name}${suffix}` : file,
             source: (await fm.readFile(file, 'utf-8')).toString(),
diff --git a/test_programs/execution_success/regression_4449/Nargo.toml b/test_programs/execution_success/regression_4449/Nargo.toml
new file mode 100644
index 00000000000..925420a03a8
--- /dev/null
+++ b/test_programs/execution_success/regression_4449/Nargo.toml
@@ -0,0 +1,6 @@
+[package]
+name = "regression_4449"
+type = "bin"
+authors = [""]
+
+[dependencies]
diff --git a/test_programs/execution_success/regression_4449/Prover.toml b/test_programs/execution_success/regression_4449/Prover.toml
new file mode 100644
index 00000000000..81af476bcc9
--- /dev/null
+++ b/test_programs/execution_success/regression_4449/Prover.toml
@@ -0,0 +1,3 @@
+
+x = 0xbd
+result = [204, 59, 83, 197, 18, 1, 128, 43, 247, 28, 104, 225, 106, 13, 20, 187, 42, 26, 67, 150, 48, 75, 238, 168, 121, 247, 142, 160, 71, 222, 97, 188]
\ No newline at end of file
diff --git a/test_programs/execution_success/regression_4449/src/main.nr b/test_programs/execution_success/regression_4449/src/main.nr
new file mode 100644
index 00000000000..454a93f5d1a
--- /dev/null
+++ b/test_programs/execution_success/regression_4449/src/main.nr
@@ -0,0 +1,14 @@
+// Regression test for issue #4449
+use dep::std;
+
+fn main(x: u8, result: [u8; 32]) {
+    let x = x % 31;
+    let mut digest = [0; 32];
+    for i in 0..70 {
+        let y = x + i;
+        let a = [y, x, 32, 0, y + 1, y - 1, y - 2, 5];
+        digest = std::sha256::digest(a);
+    }
+
+    assert(digest == result);
+}
diff --git a/test_programs/execution_success/slices/src/main.nr b/test_programs/execution_success/slices/src/main.nr
index eca42a660c4..6823bf05d96 100644
--- a/test_programs/execution_success/slices/src/main.nr
+++ b/test_programs/execution_success/slices/src/main.nr
@@ -50,6 +50,8 @@ fn main(x: Field, y: pub Field) {
     // The parameters to this function must come from witness values (inputs to main)
     regression_merge_slices(x, y);
     regression_2370();
+
+    regression_4506();
 }
 // Ensure that slices of struct/tuple values work.
 fn regression_2083() {
@@ -297,3 +299,8 @@ fn regression_2370() {
     let mut slice = [];
     slice = [1, 2, 3];
 }
+
+fn regression_4506() {
+    let slice: [Field] = [1, 2, 3];
+    assert(slice == slice);
+}
diff --git a/tooling/bb_abstraction_leaks/build.rs b/tooling/bb_abstraction_leaks/build.rs
index f9effd5d991..0bd2b1c076a 100644
--- a/tooling/bb_abstraction_leaks/build.rs
+++ b/tooling/bb_abstraction_leaks/build.rs
@@ -10,7 +10,7 @@ use const_format::formatcp;
 
 const USERNAME: &str = "AztecProtocol";
 const REPO: &str = "aztec-packages";
-const VERSION: &str = "0.24.0";
+const VERSION: &str = "0.26.3";
 const TAG: &str = formatcp!("aztec-packages-v{}", VERSION);
 
 const API_URL: &str =
diff --git a/tooling/debugger/ignored-tests.txt b/tooling/debugger/ignored-tests.txt
index c472e828739..231d4d897a9 100644
--- a/tooling/debugger/ignored-tests.txt
+++ b/tooling/debugger/ignored-tests.txt
@@ -1,21 +1,13 @@
 array_dynamic_blackbox_input
-array_sort
-assign_ex
+bigint
 bit_shifts_comptime
-brillig_cow
-brillig_nested_arrays
 brillig_references
 brillig_to_bytes_integration
 debug_logs
 double_verify_nested_proof
 double_verify_proof
 modulus
-nested_array_dynamic
-nested_array_in_slice
-nested_arrays_from_brillig
 references
 scalar_mul
 signed_comparison
-simple_2d_array
 to_bytes_integration
-bigint
diff --git a/tooling/debugger/src/context.rs b/tooling/debugger/src/context.rs
index 515edf0bb06..a3ee89263a4 100644
--- a/tooling/debugger/src/context.rs
+++ b/tooling/debugger/src/context.rs
@@ -8,11 +8,14 @@ use acvm::pwg::{
 };
 use acvm::{BlackBoxFunctionSolver, FieldElement};
 
-use nargo::artifacts::debug::DebugArtifact;
+use codespan_reporting::files::{Files, SimpleFile};
+use fm::FileId;
+use nargo::artifacts::debug::{DebugArtifact, StackFrame};
 use nargo::errors::{ExecutionError, Location};
 use nargo::NargoError;
-use noirc_printable_type::{PrintableType, PrintableValue};
+use noirc_driver::DebugFile;
 
+use std::collections::BTreeMap;
 use std::collections::{hash_set::Iter, HashSet};
 
 #[derive(Debug)]
@@ -29,6 +32,7 @@ pub(super) struct DebugContext<'a, B: BlackBoxFunctionSolver> {
     foreign_call_executor: Box<dyn DebugForeignCallExecutor + 'a>,
     debug_artifact: &'a DebugArtifact,
     breakpoints: HashSet<OpcodeLocation>,
+    source_to_opcodes: BTreeMap<FileId, Vec<(usize, OpcodeLocation)>>,
 }
 
 impl<'a, B: BlackBoxFunctionSolver> DebugContext<'a, B> {
@@ -39,12 +43,14 @@ impl<'a, B: BlackBoxFunctionSolver> DebugContext<'a, B> {
         initial_witness: WitnessMap,
         foreign_call_executor: Box<dyn DebugForeignCallExecutor + 'a>,
     ) -> Self {
+        let source_to_opcodes = build_source_to_opcode_debug_mappings(debug_artifact);
         Self {
             acvm: ACVM::new(blackbox_solver, &circuit.opcodes, initial_witness),
             brillig_solver: None,
             foreign_call_executor,
             debug_artifact,
             breakpoints: HashSet::new(),
+            source_to_opcodes,
         }
     }
 
@@ -100,10 +106,50 @@ impl<'a, B: BlackBoxFunctionSolver> DebugContext<'a, B> {
         self.debug_artifact
             .file_map
             .get(&location.file)
-            .map(|file| file.path.starts_with("__debug/"))
+            .map(is_debug_file_in_debug_crate)
             .unwrap_or(false)
     }
 
+    /// Find an opcode location matching a source code location
+    // We apply some heuristics here, and there are four possibilities for the
+    // return value of this function:
+    // 1. the source location is not found -> None
+    // 2. an exact unique location is found (very rare) -> Some(opcode_location)
+    // 3. an exact but not unique location is found, ie. a source location may
+    //    be mapped to multiple opcodes, and those may be disjoint, for example for
+    //    functions called multiple times throughout the program
+    //    -> return the first opcode in program order that matches the source location
+    // 4. exact location is not found, so an opcode for a nearby source location
+    //    is returned (this again could actually be more than one opcodes)
+    //    -> return the opcode for the next source line that is mapped
+    pub(super) fn find_opcode_for_source_location(
+        &self,
+        file_id: &FileId,
+        line: i64,
+    ) -> Option<OpcodeLocation> {
+        let line = line as usize;
+        let Some(line_to_opcodes) = self.source_to_opcodes.get(file_id) else {
+            return None;
+        };
+        let found_index = match line_to_opcodes.binary_search_by(|x| x.0.cmp(&line)) {
+            Ok(index) => {
+                // move backwards to find the first opcode which matches the line
+                let mut index = index;
+                while index > 0 && line_to_opcodes[index - 1].0 == line {
+                    index -= 1;
+                }
+                line_to_opcodes[index].1
+            }
+            Err(index) => {
+                if index >= line_to_opcodes.len() {
+                    return None;
+                }
+                line_to_opcodes[index].1
+            }
+        };
+        Some(found_index)
+    }
+
     /// Returns the callstack in source code locations for the currently
     /// executing opcode. This can be `None` if the execution finished (and
     /// `get_current_opcode_location()` returns `None`) or if the opcode is not
@@ -128,6 +174,9 @@ impl<'a, B: BlackBoxFunctionSolver> DebugContext<'a, B> {
         &self,
         opcode_location: &OpcodeLocation,
     ) -> Vec<Location> {
+        // TODO: this assumes we're debugging a program (ie. the DebugArtifact
+        // will contain a single DebugInfo), but this assumption doesn't hold
+        // for contracts
         self.debug_artifact.debug_symbols[0]
             .opcode_location(opcode_location)
             .map(|source_locations| {
@@ -467,10 +516,14 @@ impl<'a, B: BlackBoxFunctionSolver> DebugContext<'a, B> {
         }
     }
 
-    pub(super) fn get_variables(&self) -> Vec<(&str, &PrintableValue, &PrintableType)> {
+    pub(super) fn get_variables(&self) -> Vec<StackFrame> {
         return self.foreign_call_executor.get_variables();
     }
 
+    pub(super) fn current_stack_frame(&self) -> Option<StackFrame> {
+        return self.foreign_call_executor.current_stack_frame();
+    }
+
     fn breakpoint_reached(&self) -> bool {
         if let Some(location) = self.get_current_opcode_location() {
             self.breakpoints.contains(&location)
@@ -526,6 +579,52 @@ impl<'a, B: BlackBoxFunctionSolver> DebugContext<'a, B> {
     }
 }
 
+fn is_debug_file_in_debug_crate(debug_file: &DebugFile) -> bool {
+    debug_file.path.starts_with("__debug/")
+}
+
+/// Builds a map from FileId to an ordered vector of tuples with line
+/// numbers and opcode locations corresponding to those line numbers
+fn build_source_to_opcode_debug_mappings(
+    debug_artifact: &DebugArtifact,
+) -> BTreeMap<FileId, Vec<(usize, OpcodeLocation)>> {
+    if debug_artifact.debug_symbols.is_empty() {
+        return BTreeMap::new();
+    }
+    let locations = &debug_artifact.debug_symbols[0].locations;
+    let simple_files: BTreeMap<_, _> = debug_artifact
+        .file_map
+        .iter()
+        .filter(|(_, debug_file)| !is_debug_file_in_debug_crate(debug_file))
+        .map(|(file_id, debug_file)| {
+            (
+                file_id,
+                SimpleFile::new(debug_file.path.to_str().unwrap(), debug_file.source.as_str()),
+            )
+        })
+        .collect();
+
+    let mut result: BTreeMap<FileId, Vec<(usize, OpcodeLocation)>> = BTreeMap::new();
+    locations.iter().for_each(|(opcode_location, source_locations)| {
+        source_locations.iter().for_each(|source_location| {
+            let span = source_location.span;
+            let file_id = source_location.file;
+            let Some(file) = simple_files.get(&file_id) else {
+                return;
+            };
+            let Ok(line_index) = file.line_index((), span.start() as usize) else {
+                return;
+            };
+            let line_number = line_index + 1;
+
+            result.entry(file_id).or_default().push((line_number, *opcode_location));
+        });
+    });
+    result.iter_mut().for_each(|(_, file_locations)| file_locations.sort_by_key(|x| (x.0, x.1)));
+
+    result
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/tooling/debugger/src/dap.rs b/tooling/debugger/src/dap.rs
index 7e67a26b257..7c722ed0a61 100644
--- a/tooling/debugger/src/dap.rs
+++ b/tooling/debugger/src/dap.rs
@@ -5,7 +5,6 @@ use std::str::FromStr;
 use acvm::acir::circuit::{Circuit, OpcodeLocation};
 use acvm::acir::native_types::WitnessMap;
 use acvm::BlackBoxFunctionSolver;
-use codespan_reporting::files::{Files, SimpleFile};
 
 use crate::context::DebugCommandResult;
 use crate::context::DebugContext;
@@ -30,15 +29,16 @@ use nargo::artifacts::debug::DebugArtifact;
 use fm::FileId;
 use noirc_driver::CompiledProgram;
 
+type BreakpointId = i64;
+
 pub struct DapSession<'a, R: Read, W: Write, B: BlackBoxFunctionSolver> {
     server: Server<R, W>,
     context: DebugContext<'a, B>,
     debug_artifact: &'a DebugArtifact,
     running: bool,
-    source_to_opcodes: BTreeMap<FileId, Vec<(usize, OpcodeLocation)>>,
-    next_breakpoint_id: i64,
-    instruction_breakpoints: Vec<(OpcodeLocation, i64)>,
-    source_breakpoints: BTreeMap<FileId, Vec<(OpcodeLocation, i64)>>,
+    next_breakpoint_id: BreakpointId,
+    instruction_breakpoints: Vec<(OpcodeLocation, BreakpointId)>,
+    source_breakpoints: BTreeMap<FileId, Vec<(OpcodeLocation, BreakpointId)>>,
 }
 
 enum ScopeReferences {
@@ -57,8 +57,6 @@ impl From<i64> for ScopeReferences {
     }
 }
 
-// BTreeMap<FileId, Vec<(usize, OpcodeLocation)>
-
 impl<'a, R: Read, W: Write, B: BlackBoxFunctionSolver> DapSession<'a, R, W, B> {
     pub fn new(
         server: Server<R, W>,
@@ -67,7 +65,6 @@ impl<'a, R: Read, W: Write, B: BlackBoxFunctionSolver> DapSession<'a, R, W, B> {
         debug_artifact: &'a DebugArtifact,
         initial_witness: WitnessMap,
     ) -> Self {
-        let source_to_opcodes = Self::build_source_to_opcode_debug_mappings(debug_artifact);
         let context = DebugContext::new(
             solver,
             circuit,
@@ -79,7 +76,6 @@ impl<'a, R: Read, W: Write, B: BlackBoxFunctionSolver> DapSession<'a, R, W, B> {
             server,
             context,
             debug_artifact,
-            source_to_opcodes,
             running: false,
             next_breakpoint_id: 1,
             instruction_breakpoints: vec![],
@@ -87,46 +83,6 @@ impl<'a, R: Read, W: Write, B: BlackBoxFunctionSolver> DapSession<'a, R, W, B> {
         }
     }
 
-    /// Builds a map from FileId to an ordered vector of tuples with line
-    /// numbers and opcode locations corresponding to those line numbers
-    fn build_source_to_opcode_debug_mappings(
-        debug_artifact: &'a DebugArtifact,
-    ) -> BTreeMap<FileId, Vec<(usize, OpcodeLocation)>> {
-        if debug_artifact.debug_symbols.is_empty() {
-            return BTreeMap::new();
-        }
-        let locations = &debug_artifact.debug_symbols[0].locations;
-        let simple_files: BTreeMap<_, _> = debug_artifact
-            .file_map
-            .iter()
-            .map(|(file_id, debug_file)| {
-                (
-                    file_id,
-                    SimpleFile::new(debug_file.path.to_str().unwrap(), debug_file.source.as_str()),
-                )
-            })
-            .collect();
-
-        let mut result: BTreeMap<FileId, Vec<(usize, OpcodeLocation)>> = BTreeMap::new();
-        locations.iter().for_each(|(opcode_location, source_locations)| {
-            if source_locations.is_empty() {
-                return;
-            }
-            let source_location = source_locations[0];
-            let span = source_location.span;
-            let file_id = source_location.file;
-            let Ok(line_index) = &simple_files[&file_id].line_index((), span.start() as usize)
-            else {
-                return;
-            };
-            let line_number = line_index + 1;
-
-            result.entry(file_id).or_default().push((line_number, *opcode_location));
-        });
-        result.iter_mut().for_each(|(_, file_locations)| file_locations.sort_by_key(|x| x.0));
-        result
-    }
-
     fn send_stopped_event(&mut self, reason: StoppedEventReason) -> Result<(), ServerError> {
         let description = format!("{:?}", &reason);
         self.server.send_event(Event::Stopped(StoppedEventBody {
@@ -230,6 +186,8 @@ impl<'a, R: Read, W: Write, B: BlackBoxFunctionSolver> DapSession<'a, R, W, B> {
     }
 
     fn build_stack_trace(&self) -> Vec<StackFrame> {
+        let stack_frames = self.context.get_variables();
+
         self.context
             .get_source_call_stack()
             .iter()
@@ -239,9 +197,15 @@ impl<'a, R: Read, W: Write, B: BlackBoxFunctionSolver> DapSession<'a, R, W, B> {
                     self.debug_artifact.location_line_number(*source_location).unwrap();
                 let column_number =
                     self.debug_artifact.location_column_number(*source_location).unwrap();
+
+                let name = match stack_frames.get(index) {
+                    Some(frame) => format!("{} {}", frame.function_name, index),
+                    None => format!("frame #{index}"),
+                };
+
                 StackFrame {
                     id: index as i64,
-                    name: format!("frame #{index}"),
+                    name,
                     source: Some(Source {
                         path: self.debug_artifact.file_map[&source_location.file]
                             .path
@@ -422,7 +386,7 @@ impl<'a, R: Read, W: Write, B: BlackBoxFunctionSolver> DapSession<'a, R, W, B> {
         Ok(())
     }
 
-    fn get_next_breakpoint_id(&mut self) -> i64 {
+    fn get_next_breakpoint_id(&mut self) -> BreakpointId {
         let id = self.next_breakpoint_id;
         self.next_breakpoint_id += 1;
         id
@@ -493,36 +457,6 @@ impl<'a, R: Read, W: Write, B: BlackBoxFunctionSolver> DapSession<'a, R, W, B> {
         found.map(|iter| *iter.0)
     }
 
-    // TODO: there are four possibilities for the return value of this function:
-    // 1. the source location is not found -> None
-    // 2. an exact unique location is found -> Some(opcode_location)
-    // 3. an exact but not unique location is found (ie. a source location may
-    //    be mapped to multiple opcodes, and those may be disjoint, for example for
-    //    functions called multiple times throughout the program)
-    // 4. exact location is not found, so an opcode for a nearby source location
-    //    is returned (this again could actually be more than one opcodes)
-    // Case 3 is not supported yet, and 4 is not correctly handled.
-    fn find_opcode_for_source_location(
-        &self,
-        file_id: &FileId,
-        line: i64,
-    ) -> Option<OpcodeLocation> {
-        let line = line as usize;
-        let Some(line_to_opcodes) = self.source_to_opcodes.get(file_id) else {
-            return None;
-        };
-        let found_index = match line_to_opcodes.binary_search_by(|x| x.0.cmp(&line)) {
-            Ok(index) => line_to_opcodes[index].1,
-            Err(index) => {
-                if index >= line_to_opcodes.len() {
-                    return None;
-                }
-                line_to_opcodes[index].1
-            }
-        };
-        Some(found_index)
-    }
-
     fn map_source_breakpoints(&mut self, args: &SetBreakpointsArguments) -> Vec<Breakpoint> {
         let Some(ref source) = &args.source.path else {
             return vec![];
@@ -539,7 +473,8 @@ impl<'a, R: Read, W: Write, B: BlackBoxFunctionSolver> DapSession<'a, R, W, B> {
             .iter()
             .map(|breakpoint| {
                 let line = breakpoint.line;
-                let Some(location) = self.find_opcode_for_source_location(&file_id, line) else {
+                let Some(location) = self.context.find_opcode_for_source_location(&file_id, line)
+                else {
                     return Breakpoint {
                         verified: false,
                         message: Some(String::from(
@@ -608,16 +543,20 @@ impl<'a, R: Read, W: Write, B: BlackBoxFunctionSolver> DapSession<'a, R, W, B> {
     }
 
     fn build_local_variables(&self) -> Vec<Variable> {
-        let mut variables: Vec<_> = self
-            .context
-            .get_variables()
+        let Some(current_stack_frame) = self.context.current_stack_frame() else {
+            return vec![];
+        };
+
+        let mut variables = current_stack_frame
+            .variables
             .iter()
             .map(|(name, value, _var_type)| Variable {
                 name: String::from(*name),
                 value: format!("{:?}", *value),
                 ..Variable::default()
             })
-            .collect();
+            .collect::<Vec<Variable>>();
+
         variables.sort_by(|a, b| a.name.partial_cmp(&b.name).unwrap());
         variables
     }
diff --git a/tooling/debugger/src/foreign_calls.rs b/tooling/debugger/src/foreign_calls.rs
index 68c4d3947b0..25f126ff490 100644
--- a/tooling/debugger/src/foreign_calls.rs
+++ b/tooling/debugger/src/foreign_calls.rs
@@ -3,17 +3,19 @@ use acvm::{
     pwg::ForeignCallWaitInfo,
 };
 use nargo::{
-    artifacts::debug::{DebugArtifact, DebugVars},
+    artifacts::debug::{DebugArtifact, DebugVars, StackFrame},
     ops::{DefaultForeignCallExecutor, ForeignCallExecutor, NargoForeignCallResult},
 };
-use noirc_errors::debug_info::DebugVarId;
-use noirc_printable_type::{ForeignCallError, PrintableType, PrintableValue};
+use noirc_errors::debug_info::{DebugFnId, DebugVarId};
+use noirc_printable_type::ForeignCallError;
 
 pub(crate) enum DebugForeignCall {
     VarAssign,
     VarDrop,
     MemberAssign(u32),
     DerefAssign,
+    FnEnter,
+    FnExit,
 }
 
 impl DebugForeignCall {
@@ -28,13 +30,16 @@ impl DebugForeignCall {
             "__debug_var_assign" => Some(DebugForeignCall::VarAssign),
             "__debug_var_drop" => Some(DebugForeignCall::VarDrop),
             "__debug_deref_assign" => Some(DebugForeignCall::DerefAssign),
+            "__debug_fn_enter" => Some(DebugForeignCall::FnEnter),
+            "__debug_fn_exit" => Some(DebugForeignCall::FnExit),
             _ => None,
         }
     }
 }
 
 pub trait DebugForeignCallExecutor: ForeignCallExecutor {
-    fn get_variables(&self) -> Vec<(&str, &PrintableValue, &PrintableType)>;
+    fn get_variables(&self) -> Vec<StackFrame>;
+    fn current_stack_frame(&self) -> Option<StackFrame>;
 }
 
 pub struct DefaultDebugForeignCallExecutor {
@@ -57,23 +62,33 @@ impl DefaultDebugForeignCallExecutor {
     }
 
     pub fn load_artifact(&mut self, artifact: &DebugArtifact) {
-        artifact.debug_symbols.iter().for_each(|info| {
-            self.debug_vars.insert_variables(&info.variables);
-            self.debug_vars.insert_types(&info.types);
-        });
+        // TODO: handle loading from the correct DebugInfo when we support
+        // debugging contracts
+        let Some(info) = artifact.debug_symbols.get(0) else {
+            return;
+        };
+        self.debug_vars.insert_debug_info(info);
     }
 }
 
 impl DebugForeignCallExecutor for DefaultDebugForeignCallExecutor {
-    fn get_variables(&self) -> Vec<(&str, &PrintableValue, &PrintableType)> {
+    fn get_variables(&self) -> Vec<StackFrame> {
         self.debug_vars.get_variables()
     }
+
+    fn current_stack_frame(&self) -> Option<StackFrame> {
+        self.debug_vars.current_stack_frame()
+    }
 }
 
 fn debug_var_id(value: &Value) -> DebugVarId {
     DebugVarId(value.to_u128() as u32)
 }
 
+fn debug_fn_id(value: &Value) -> DebugFnId {
+    DebugFnId(value.to_u128() as u32)
+}
+
 impl ForeignCallExecutor for DefaultDebugForeignCallExecutor {
     fn execute(
         &mut self,
@@ -136,6 +151,19 @@ impl ForeignCallExecutor for DefaultDebugForeignCallExecutor {
                 }
                 Ok(ForeignCallResult::default().into())
             }
+            Some(DebugForeignCall::FnEnter) => {
+                let fcp_fn_id = &foreign_call.inputs[0];
+                let ForeignCallParam::Single(fn_id_value) = fcp_fn_id else {
+                    panic!("unexpected foreign call parameter in fn enter: {fcp_fn_id:?}")
+                };
+                let fn_id = debug_fn_id(fn_id_value);
+                self.debug_vars.push_fn(fn_id);
+                Ok(ForeignCallResult::default().into())
+            }
+            Some(DebugForeignCall::FnExit) => {
+                self.debug_vars.pop_fn();
+                Ok(ForeignCallResult::default().into())
+            }
             None => self.executor.execute(foreign_call),
         }
     }
diff --git a/tooling/debugger/src/repl.rs b/tooling/debugger/src/repl.rs
index 8441dbde9be..41dbf604f99 100644
--- a/tooling/debugger/src/repl.rs
+++ b/tooling/debugger/src/repl.rs
@@ -337,11 +337,13 @@ impl<'a, B: BlackBoxFunctionSolver> ReplDebugger<'a, B> {
     }
 
     pub fn show_vars(&self) {
-        let vars = self.context.get_variables();
-        for (var_name, value, var_type) in vars.iter() {
-            let printable_value =
-                PrintableValueDisplay::Plain((*value).clone(), (*var_type).clone());
-            println!("{var_name}:{var_type:?} = {}", printable_value);
+        for frame in self.context.get_variables() {
+            println!("{}({})", frame.function_name, frame.function_params.join(", "));
+            for (var_name, value, var_type) in frame.variables.iter() {
+                let printable_value =
+                    PrintableValueDisplay::Plain((*value).clone(), (*var_type).clone());
+                println!("  {var_name}:{var_type:?} = {}", printable_value);
+            }
         }
     }
 
@@ -530,7 +532,7 @@ pub fn run<B: BlackBoxFunctionSolver>(
         .add(
             "vars",
             command! {
-                "show variable values available at this point in execution",
+                "show variables for each function scope available at this point in execution",
                 () => || {
                     ref_context.borrow_mut().show_vars();
                     Ok(CommandStatus::Done)
diff --git a/tooling/debugger/src/source_code_printer.rs b/tooling/debugger/src/source_code_printer.rs
index b5ffdb12d01..e298eb8aadd 100644
--- a/tooling/debugger/src/source_code_printer.rs
+++ b/tooling/debugger/src/source_code_printer.rs
@@ -30,7 +30,7 @@ struct LocationPrintContext {
 // Given a DebugArtifact and an OpcodeLocation, prints all the source code
 // locations the OpcodeLocation maps to, with some surrounding context and
 // visual aids to highlight the location itself.
-pub(crate) fn print_source_code_location(debug_artifact: &DebugArtifact, locations: &[Location]) {
+pub(super) fn print_source_code_location(debug_artifact: &DebugArtifact, locations: &[Location]) {
     let locations = locations.iter();
 
     for loc in locations {
@@ -269,8 +269,12 @@ mod tests {
         let mut opcode_locations = BTreeMap::<OpcodeLocation, Vec<Location>>::new();
         opcode_locations.insert(OpcodeLocation::Acir(42), vec![loc]);
 
-        let debug_symbols =
-            vec![DebugInfo::new(opcode_locations, BTreeMap::default(), BTreeMap::default())];
+        let debug_symbols = vec![DebugInfo::new(
+            opcode_locations,
+            BTreeMap::default(),
+            BTreeMap::default(),
+            BTreeMap::default(),
+        )];
         let debug_artifact = DebugArtifact::new(debug_symbols, &fm);
 
         let location_rendered: Vec<_> = render_location(&debug_artifact, &loc).collect();
diff --git a/tooling/debugger/tests/debug.rs b/tooling/debugger/tests/debug.rs
index 4cb678192b8..143ee7987f8 100644
--- a/tooling/debugger/tests/debug.rs
+++ b/tooling/debugger/tests/debug.rs
@@ -12,7 +12,7 @@ mod tests {
         let nargo_bin =
             cargo_bin("nargo").into_os_string().into_string().expect("Cannot parse nargo path");
 
-        let mut dbg_session = spawn_bash(Some(10000)).expect("Could not start bash session");
+        let mut dbg_session = spawn_bash(Some(15000)).expect("Could not start bash session");
 
         // Set backend to `/dev/null` to force an error if nargo tries to speak to a backend.
         dbg_session
diff --git a/tooling/nargo/src/artifacts/debug.rs b/tooling/nargo/src/artifacts/debug.rs
index a249ecb03ad..fbdf59805c9 100644
--- a/tooling/nargo/src/artifacts/debug.rs
+++ b/tooling/nargo/src/artifacts/debug.rs
@@ -8,7 +8,7 @@ use std::{
     ops::Range,
 };
 
-pub use super::debug_vars::DebugVars;
+pub use super::debug_vars::{DebugVars, StackFrame};
 use fm::{FileId, FileManager, PathString};
 
 /// A Debug Artifact stores, for a given program, the debug info for every function
@@ -231,8 +231,12 @@ mod tests {
         let mut opcode_locations = BTreeMap::<OpcodeLocation, Vec<Location>>::new();
         opcode_locations.insert(OpcodeLocation::Acir(42), vec![loc]);
 
-        let debug_symbols =
-            vec![DebugInfo::new(opcode_locations, BTreeMap::default(), BTreeMap::default())];
+        let debug_symbols = vec![DebugInfo::new(
+            opcode_locations,
+            BTreeMap::default(),
+            BTreeMap::default(),
+            BTreeMap::default(),
+        )];
         let debug_artifact = DebugArtifact::new(debug_symbols, &fm);
 
         let location_in_line = debug_artifact.location_in_line(loc).expect("Expected a range");
diff --git a/tooling/nargo/src/artifacts/debug_vars.rs b/tooling/nargo/src/artifacts/debug_vars.rs
index 20f2637f7d6..66568bec833 100644
--- a/tooling/nargo/src/artifacts/debug_vars.rs
+++ b/tooling/nargo/src/artifacts/debug_vars.rs
@@ -1,54 +1,85 @@
 use acvm::brillig_vm::brillig::Value;
 use noirc_errors::debug_info::{
-    DebugTypeId, DebugTypes, DebugVarId, DebugVariable, DebugVariables,
+    DebugFnId, DebugFunction, DebugInfo, DebugTypeId, DebugVarId, DebugVariable,
 };
 use noirc_printable_type::{decode_value, PrintableType, PrintableValue};
-use std::collections::{HashMap, HashSet};
+use std::collections::HashMap;
 
 #[derive(Debug, Default, Clone)]
 pub struct DebugVars {
     variables: HashMap<DebugVarId, DebugVariable>,
+    functions: HashMap<DebugFnId, DebugFunction>,
     types: HashMap<DebugTypeId, PrintableType>,
-    active: HashSet<DebugVarId>,
-    values: HashMap<DebugVarId, PrintableValue>,
+    frames: Vec<(DebugFnId, HashMap<DebugVarId, PrintableValue>)>,
+}
+
+pub struct StackFrame<'a> {
+    pub function_name: &'a str,
+    pub function_params: Vec<&'a str>,
+    pub variables: Vec<(&'a str, &'a PrintableValue, &'a PrintableType)>,
 }
 
 impl DebugVars {
-    pub fn get_variables(&self) -> Vec<(&str, &PrintableValue, &PrintableType)> {
-        self.active
-            .iter()
-            .filter_map(|var_id| {
-                self.variables.get(var_id).and_then(|debug_var| {
-                    let Some(value) = self.values.get(var_id) else {
-                        return None;
-                    };
-                    let Some(ptype) = self.types.get(&debug_var.debug_type_id) else {
-                        return None;
-                    };
-                    Some((debug_var.name.as_str(), value, ptype))
-                })
-            })
-            .collect()
+    pub fn insert_debug_info(&mut self, info: &DebugInfo) {
+        self.variables.extend(info.variables.clone());
+        self.types.extend(info.types.clone());
+        self.functions.extend(info.functions.clone());
+    }
+
+    pub fn get_variables(&self) -> Vec<StackFrame> {
+        self.frames.iter().map(|(fn_id, frame)| self.build_stack_frame(fn_id, frame)).collect()
     }
 
-    pub fn insert_variables(&mut self, vars: &DebugVariables) {
-        self.variables.extend(vars.clone());
+    pub fn current_stack_frame(&self) -> Option<StackFrame> {
+        self.frames.last().map(|(fn_id, frame)| self.build_stack_frame(fn_id, frame))
     }
 
-    pub fn insert_types(&mut self, types: &DebugTypes) {
-        self.types.extend(types.clone());
+    fn lookup_var(&self, var_id: DebugVarId) -> Option<(&str, &PrintableType)> {
+        self.variables.get(&var_id).and_then(|debug_var| {
+            let Some(ptype) = self.types.get(&debug_var.debug_type_id) else {
+                return None;
+            };
+            Some((debug_var.name.as_str(), ptype))
+        })
+    }
+
+    fn build_stack_frame<'a>(
+        &'a self,
+        fn_id: &DebugFnId,
+        frame: &'a HashMap<DebugVarId, PrintableValue>,
+    ) -> StackFrame {
+        let debug_fn = &self.functions.get(fn_id).expect("failed to find function metadata");
+
+        let params: Vec<&str> =
+            debug_fn.arg_names.iter().map(|arg_name| arg_name.as_str()).collect();
+        let vars: Vec<(&str, &PrintableValue, &PrintableType)> = frame
+            .iter()
+            .filter_map(|(var_id, var_value)| {
+                self.lookup_var(*var_id).map(|(name, typ)| (name, var_value, typ))
+            })
+            .collect();
+
+        StackFrame {
+            function_name: debug_fn.name.as_str(),
+            function_params: params,
+            variables: vars,
+        }
     }
 
     pub fn assign_var(&mut self, var_id: DebugVarId, values: &[Value]) {
-        self.active.insert(var_id);
         let type_id = &self.variables.get(&var_id).unwrap().debug_type_id;
         let ptype = self.types.get(type_id).unwrap();
-        self.values.insert(var_id, decode_value(&mut values.iter().map(|v| v.to_field()), ptype));
+
+        self.frames
+            .last_mut()
+            .expect("unexpected empty stack frames")
+            .1
+            .insert(var_id, decode_value(&mut values.iter().map(|v| v.to_field()), ptype));
     }
 
     pub fn assign_field(&mut self, var_id: DebugVarId, indexes: Vec<u32>, values: &[Value]) {
-        let mut cursor: &mut PrintableValue = self
-            .values
+        let current_frame = &mut self.frames.last_mut().expect("unexpected empty stack frames").1;
+        let mut cursor: &mut PrintableValue = current_frame
             .get_mut(&var_id)
             .unwrap_or_else(|| panic!("value unavailable for var_id {var_id:?}"));
         let cursor_type_id = &self
@@ -102,7 +133,6 @@ impl DebugVars {
             };
         }
         *cursor = decode_value(&mut values.iter().map(|v| v.to_field()), cursor_type);
-        self.active.insert(var_id);
     }
 
     pub fn assign_deref(&mut self, _var_id: DebugVarId, _values: &[Value]) {
@@ -114,6 +144,14 @@ impl DebugVars {
     }
 
     pub fn drop_var(&mut self, var_id: DebugVarId) {
-        self.active.remove(&var_id);
+        self.frames.last_mut().expect("unexpected empty stack frames").1.remove(&var_id);
+    }
+
+    pub fn push_fn(&mut self, fn_id: DebugFnId) {
+        self.frames.push((fn_id, HashMap::default()));
+    }
+
+    pub fn pop_fn(&mut self) {
+        self.frames.pop();
     }
 }
diff --git a/tooling/noir_js_backend_barretenberg/package.json b/tooling/noir_js_backend_barretenberg/package.json
index 28c3609fd14..06c034725e3 100644
--- a/tooling/noir_js_backend_barretenberg/package.json
+++ b/tooling/noir_js_backend_barretenberg/package.json
@@ -42,7 +42,7 @@
     "lint": "NODE_NO_WARNINGS=1 eslint . --ext .ts --ignore-path ./.eslintignore  --max-warnings 0"
   },
   "dependencies": {
-    "@aztec/bb.js": "0.24.0",
+    "@aztec/bb.js": "0.26.3",
     "@noir-lang/types": "workspace:*",
     "fflate": "^0.8.0"
   },
diff --git a/yarn.lock b/yarn.lock
index f5f3a29f08a..49485193532 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -221,9 +221,9 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@aztec/bb.js@npm:0.24.0":
-  version: 0.24.0
-  resolution: "@aztec/bb.js@npm:0.24.0"
+"@aztec/bb.js@npm:0.26.3":
+  version: 0.26.3
+  resolution: "@aztec/bb.js@npm:0.26.3"
   dependencies:
     comlink: ^4.4.1
     commander: ^10.0.1
@@ -231,7 +231,7 @@ __metadata:
     tslib: ^2.4.0
   bin:
     bb.js: dest/node/main.js
-  checksum: a086dabf30084cfa526e512148b9c02f0a0770dcc19b7dca4af9a3e98612b716acc7eaac6b52c0f12d985932e866d1cb9e534ded6ac9d747f3dd021afe25de27
+  checksum: 74c2b7ef5405f56472cf7c41d1c13261df07b1d5019e3ede9b63d218378e0fb73ccf5c52f1cc524505efad5799b347b497349d7c9b6fe82286014b1574f12309
   languageName: node
   linkType: hard
 
@@ -4396,7 +4396,7 @@ __metadata:
   version: 0.0.0-use.local
   resolution: "@noir-lang/backend_barretenberg@workspace:tooling/noir_js_backend_barretenberg"
   dependencies:
-    "@aztec/bb.js": 0.24.0
+    "@aztec/bb.js": 0.26.3
     "@noir-lang/types": "workspace:*"
     "@types/node": ^20.6.2
     "@types/prettier": ^3