diff --git a/Cargo.lock b/Cargo.lock
index 6811bcd..f62c495 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -269,6 +269,15 @@ version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "790eea4361631c5e7d22598ecd5723ff611904e3344ce8720784c93e3d83d40b"
 
+[[package]]
+name = "crossbeam-channel"
+version = "0.5.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "06ba6d68e24814cb8de6bb986db8222d3a027d15872cabc0d18817bc3c0e4471"
+dependencies = [
+ "crossbeam-utils",
+]
+
 [[package]]
 name = "crossbeam-deque"
 version = "0.8.5"
@@ -335,6 +344,7 @@ dependencies = [
  "annotate-snippets",
  "colored",
  "criterion",
+ "crossbeam-channel",
  "getrandom",
  "rand",
  "serde",
diff --git a/dust-lang/Cargo.toml b/dust-lang/Cargo.toml
index bef5fb8..96fedb5 100644
--- a/dust-lang/Cargo.toml
+++ b/dust-lang/Cargo.toml
@@ -12,7 +12,7 @@ version.workspace = true
 annotate-snippets = "0.11.4"
 colored = "2.1.0"
 rand = "0.8.5"
-serde = { version = "1.0.203", features = ["derive"] }
+serde = { version = "1.0.203", features = ["derive", "rc"] }
 serde_json = "1.0.117"
 getrandom = { version = "0.2", features = [
     "js",
@@ -21,6 +21,7 @@ smartstring = { version = "1.0.1", features = [
     "serde",
 ], default-features = false }
 tracing = "0.1.41"
+crossbeam-channel = "0.5.14"
 
 [dev-dependencies]
 criterion = { version = "0.3.4", features = ["html_reports"] }
@@ -33,6 +34,10 @@ harness = false
 name = "fibonacci"
 harness = false
 
+[[bench]]
+name = "threads"
+harness = false
+
 [[test]]
 name = "logic_and"
 path = "tests/logic/and.rs"
diff --git a/dust-lang/benches/threads.rs b/dust-lang/benches/threads.rs
new file mode 100644
index 0000000..8c4ef2e
--- /dev/null
+++ b/dust-lang/benches/threads.rs
@@ -0,0 +1,31 @@
+use std::time::Duration;
+
+use criterion::{Criterion, black_box, criterion_group, criterion_main};
+use dust_lang::run;
+
+const SOURCE: &str = r#"
+    let mut i = 0
+
+    while i < 1_000 {
+        i += 1
+
+        spawn(
+            fn () { random_int(0, 10); }
+        )
+    }
+"#;
+
+fn threads(source: &str) {
+    run(source).unwrap();
+}
+
+fn criterion_benchmark(c: &mut Criterion) {
+    let mut group = c.benchmark_group("threads");
+
+    group.measurement_time(Duration::from_secs(15));
+    group.bench_function("threads", |b| b.iter(|| threads(black_box(SOURCE))));
+    group.finish();
+}
+
+criterion_group!(benches, criterion_benchmark);
+criterion_main!(benches);
diff --git a/dust-lang/src/chunk/mod.rs b/dust-lang/src/chunk/mod.rs
index 07c7eae..d9a7364 100644
--- a/dust-lang/src/chunk/mod.rs
+++ b/dust-lang/src/chunk/mod.rs
@@ -23,6 +23,7 @@ pub use scope::Scope;
 
 use std::fmt::{self, Debug, Display, Formatter, Write as FmtWrite};
 use std::io::Write;
+use std::sync::Arc;
 
 use serde::{Deserialize, Serialize};
 
@@ -40,7 +41,7 @@ pub struct Chunk {
     pub(crate) positions: Vec<Span>,
     pub(crate) constants: Vec<Value>,
     pub(crate) locals: Vec<Local>,
-    pub(crate) prototypes: Vec<Chunk>,
+    pub(crate) prototypes: Vec<Arc<Chunk>>,
 
     pub(crate) register_count: usize,
     pub(crate) prototype_index: u8,
@@ -55,7 +56,7 @@ impl Chunk {
         positions: impl Into<Vec<Span>>,
         constants: impl Into<Vec<Value>>,
         locals: impl Into<Vec<Local>>,
-        prototypes: Vec<Chunk>,
+        prototypes: impl IntoIterator<Item = Chunk>,
     ) -> Self {
         Self {
             name,
@@ -64,7 +65,7 @@ impl Chunk {
             positions: positions.into(),
             constants: constants.into(),
             locals: locals.into(),
-            prototypes,
+            prototypes: prototypes.into_iter().map(Arc::new).collect(),
             register_count: 0,
             prototype_index: 0,
         }
diff --git a/dust-lang/src/compiler/mod.rs b/dust-lang/src/compiler/mod.rs
index edbb040..270fc81 100644
--- a/dust-lang/src/compiler/mod.rs
+++ b/dust-lang/src/compiler/mod.rs
@@ -28,7 +28,7 @@ use parse_rule::{ParseRule, Precedence};
 use tracing::{Level, debug, info, span};
 use type_checks::{check_math_type, check_math_types};
 
-use std::mem::replace;
+use std::{mem::replace, sync::Arc};
 
 use optimize::control_flow_register_consolidation;
 
@@ -96,7 +96,7 @@ pub struct Compiler<'src> {
 
     /// Prototypes that have been compiled. These are assigned to the chunk when
     /// [`Compiler::finish`] is called.
-    prototypes: Vec<Chunk>,
+    prototypes: Vec<Arc<Chunk>>,
 
     /// Maximum stack size required by the chunk. This is assigned to the chunk when
     /// [`Compiler::finish`] is called.
@@ -1645,7 +1645,7 @@ impl<'src> Compiler<'src> {
         let chunk = function_compiler.finish();
         let destination = self.next_register();
 
-        self.prototypes.push(chunk);
+        self.prototypes.push(Arc::new(chunk));
 
         if let Some(identifier) = identifier {
             self.declare_local(
diff --git a/dust-lang/src/lexer.rs b/dust-lang/src/lexer.rs
index 0c09983..df03324 100644
--- a/dust-lang/src/lexer.rs
+++ b/dust-lang/src/lexer.rs
@@ -5,7 +5,7 @@
 //! - [`Lexer`], which lexes the input a token at a time
 use serde::{Deserialize, Serialize};
 
-use crate::{dust_error::AnnotatedError, CompileError, DustError, Span, Token};
+use crate::{CompileError, DustError, Span, Token, dust_error::AnnotatedError};
 
 /// Lexes the input and returns a vector of tokens and their positions.
 ///
@@ -83,7 +83,7 @@ impl<'src> Lexer<'src> {
         self.skip_whitespace();
 
         let (token, span) = if let Some(character) = self.peek_char() {
-            let lexer = LexRule::from(&character).lexer;
+            let lexer = LexRule::from(&character).lex_action;
 
             lexer(self)?
         } else {
@@ -613,92 +613,92 @@ impl<'src> Lexer<'src> {
     }
 }
 
-type LexerFn<'src> = fn(&mut Lexer<'src>) -> Result<(Token<'src>, Span), LexError>;
+type LexAction<'src> = fn(&mut Lexer<'src>) -> Result<(Token<'src>, Span), LexError>;
 
 pub struct LexRule<'src> {
-    lexer: LexerFn<'src>,
+    lex_action: LexAction<'src>,
 }
 
 impl From<&char> for LexRule<'_> {
     fn from(char: &char) -> Self {
         match char {
             '0'..='9' => LexRule {
-                lexer: Lexer::lex_numeric,
+                lex_action: Lexer::lex_numeric,
             },
             char if char.is_alphabetic() => LexRule {
-                lexer: Lexer::lex_keyword_or_identifier,
+                lex_action: Lexer::lex_keyword_or_identifier,
             },
             '"' => LexRule {
-                lexer: Lexer::lex_string,
+                lex_action: Lexer::lex_string,
             },
             '\'' => LexRule {
-                lexer: Lexer::lex_char,
+                lex_action: Lexer::lex_char,
             },
             '+' => LexRule {
-                lexer: Lexer::lex_plus,
+                lex_action: Lexer::lex_plus,
             },
             '-' => LexRule {
-                lexer: Lexer::lex_minus,
+                lex_action: Lexer::lex_minus,
             },
             '*' => LexRule {
-                lexer: Lexer::lex_star,
+                lex_action: Lexer::lex_star,
             },
             '/' => LexRule {
-                lexer: Lexer::lex_slash,
+                lex_action: Lexer::lex_slash,
             },
             '%' => LexRule {
-                lexer: Lexer::lex_percent,
+                lex_action: Lexer::lex_percent,
             },
             '!' => LexRule {
-                lexer: Lexer::lex_exclamation_mark,
+                lex_action: Lexer::lex_exclamation_mark,
             },
             '=' => LexRule {
-                lexer: Lexer::lex_equal,
+                lex_action: Lexer::lex_equal,
             },
             '<' => LexRule {
-                lexer: Lexer::lex_less_than,
+                lex_action: Lexer::lex_less_than,
             },
             '>' => LexRule {
-                lexer: Lexer::lex_greater_than,
+                lex_action: Lexer::lex_greater_than,
             },
             '&' => LexRule {
-                lexer: Lexer::lex_ampersand,
+                lex_action: Lexer::lex_ampersand,
             },
             '|' => LexRule {
-                lexer: Lexer::lex_pipe,
+                lex_action: Lexer::lex_pipe,
             },
             '(' => LexRule {
-                lexer: Lexer::lex_left_parenthesis,
+                lex_action: Lexer::lex_left_parenthesis,
             },
             ')' => LexRule {
-                lexer: Lexer::lex_right_parenthesis,
+                lex_action: Lexer::lex_right_parenthesis,
             },
             '[' => LexRule {
-                lexer: Lexer::lex_left_bracket,
+                lex_action: Lexer::lex_left_bracket,
             },
             ']' => LexRule {
-                lexer: Lexer::lex_right_bracket,
+                lex_action: Lexer::lex_right_bracket,
             },
             '{' => LexRule {
-                lexer: Lexer::lex_left_brace,
+                lex_action: Lexer::lex_left_brace,
             },
             '}' => LexRule {
-                lexer: Lexer::lex_right_brace,
+                lex_action: Lexer::lex_right_brace,
             },
             ';' => LexRule {
-                lexer: Lexer::lex_semicolon,
+                lex_action: Lexer::lex_semicolon,
             },
             ':' => LexRule {
-                lexer: Lexer::lex_colon,
+                lex_action: Lexer::lex_colon,
             },
             ',' => LexRule {
-                lexer: Lexer::lex_comma,
+                lex_action: Lexer::lex_comma,
             },
             '.' => LexRule {
-                lexer: Lexer::lex_dot,
+                lex_action: Lexer::lex_dot,
             },
             _ => LexRule {
-                lexer: Lexer::lex_unexpected,
+                lex_action: Lexer::lex_unexpected,
             },
         }
     }
diff --git a/dust-lang/src/native_function/assert.rs b/dust-lang/src/native_function/assert.rs
index b2704a4..b748ee7 100644
--- a/dust-lang/src/native_function/assert.rs
+++ b/dust-lang/src/native_function/assert.rs
@@ -2,7 +2,7 @@ use std::{ops::Range, panic};
 
 use crate::vm::ThreadData;
 
-pub fn panic(data: &mut ThreadData, _: Option<u8>, argument_range: Range<u8>) -> bool {
+pub fn panic(data: &mut ThreadData, _: u8, argument_range: Range<u8>) -> bool {
     let position = data.current_position();
     let mut message = format!("Dust panic at {position}!");
 
diff --git a/dust-lang/src/native_function/io.rs b/dust-lang/src/native_function/io.rs
index 0267009..696e5d5 100644
--- a/dust-lang/src/native_function/io.rs
+++ b/dust-lang/src/native_function/io.rs
@@ -1,17 +1,12 @@
-use std::io::{stdin, stdout, Write};
+use std::io::{Write, stdin, stdout};
 use std::ops::Range;
 
 use crate::{
-    vm::{get_next_action, Register, ThreadData},
     ConcreteValue, Value,
+    vm::{Register, ThreadData, get_next_action},
 };
 
-pub fn read_line(
-    data: &mut ThreadData,
-    destination: Option<u8>,
-    _argument_range: Range<u8>,
-) -> bool {
-    let destination = destination.unwrap();
+pub fn read_line(data: &mut ThreadData, destination: u8, _argument_range: Range<u8>) -> bool {
     let mut buffer = String::new();
 
     if stdin().read_line(&mut buffer).is_ok() {
@@ -29,7 +24,7 @@ pub fn read_line(
     false
 }
 
-pub fn write(data: &mut ThreadData, _destination: Option<u8>, argument_range: Range<u8>) -> bool {
+pub fn write(data: &mut ThreadData, _: u8, argument_range: Range<u8>) -> bool {
     let mut stdout = stdout();
 
     for register_index in argument_range {
@@ -45,11 +40,7 @@ pub fn write(data: &mut ThreadData, _destination: Option<u8>, argument_range: Ra
     false
 }
 
-pub fn write_line(
-    data: &mut ThreadData,
-    _destination: Option<u8>,
-    argument_range: Range<u8>,
-) -> bool {
+pub fn write_line(data: &mut ThreadData, _: u8, argument_range: Range<u8>) -> bool {
     let mut stdout = stdout().lock();
 
     for register_index in argument_range {
diff --git a/dust-lang/src/native_function/mod.rs b/dust-lang/src/native_function/mod.rs
index e56f54a..4917843 100644
--- a/dust-lang/src/native_function/mod.rs
+++ b/dust-lang/src/native_function/mod.rs
@@ -4,7 +4,9 @@
 //! itself or that are more efficient to implement in Rust.
 mod assert;
 mod io;
+mod random;
 mod string;
+mod thread;
 
 use std::{
     fmt::{self, Display, Formatter},
@@ -15,7 +17,7 @@ use std::{
 
 use serde::{Deserialize, Serialize};
 
-use crate::{vm::ThreadData, AnnotatedError, FunctionType, Span, Type};
+use crate::{AnnotatedError, FunctionType, Span, Type, vm::ThreadData};
 
 macro_rules! define_native_function {
     ($(($name:ident, $bytes:literal, $str:expr, $type:expr, $function:expr)),*) => {
@@ -33,7 +35,7 @@ macro_rules! define_native_function {
             pub fn call(
                 &self,
                 data: &mut ThreadData,
-                destination: Option<u8>,
+                destination: u8,
                 argument_range: Range<u8>,
             ) -> bool {
                 match self {
@@ -244,11 +246,42 @@ define_native_function! {
             return_type: Type::None
         },
         io::write_line
-    )
+    ),
 
     // // Random
-    // (Random, 58_u8, "random", true),
-    // (RandomInRange, 59_u8, "random_in_range", true)
+    (
+        RandomInteger,
+        58,
+        "random_int",
+        FunctionType {
+            type_parameters: Vec::with_capacity(0),
+            value_parameters: vec![(0, Type::Integer), (1, Type::Integer)],
+            return_type: Type::Integer
+        },
+        random::random_int
+    ),
+
+    // Thread
+    (
+        Spawn,
+        60,
+        "spawn",
+        FunctionType {
+            type_parameters: Vec::with_capacity(0),
+            value_parameters: vec![
+                (
+                    0,
+                    Type::Function(Box::new(FunctionType {
+                        type_parameters: Vec::with_capacity(0),
+                        value_parameters: Vec::with_capacity(0),
+                        return_type: Type::Any
+                    }))
+                )
+            ],
+            return_type: Type::None
+        },
+        thread::spawn
+    )
 }
 
 #[derive(Debug, Clone, PartialEq)]
diff --git a/dust-lang/src/native_function/random.rs b/dust-lang/src/native_function/random.rs
new file mode 100644
index 0000000..f743b0b
--- /dev/null
+++ b/dust-lang/src/native_function/random.rs
@@ -0,0 +1,40 @@
+use std::ops::Range;
+
+use rand::Rng;
+
+use crate::{
+    Value,
+    vm::{Register, ThreadData, get_next_action},
+};
+
+pub fn random_int(data: &mut ThreadData, destination: u8, argument_range: Range<u8>) -> bool {
+    let mut argument_range_iter = argument_range.into_iter();
+    let (min, max) = {
+        let mut min = None;
+
+        loop {
+            let register_index = argument_range_iter
+                .next()
+                .unwrap_or_else(|| panic!("No argument was passed to \"random_int\""));
+            let value_option = data.open_register_allow_empty_unchecked(register_index);
+
+            if let Some(argument) = value_option {
+                if let Some(integer) = argument.as_integer() {
+                    if min.is_none() {
+                        min = Some(integer);
+                    } else {
+                        break (min, integer);
+                    }
+                }
+            }
+        }
+    };
+
+    let random_integer = rand::thread_rng().gen_range(min.unwrap()..max);
+
+    data.set_register(destination, Register::Value(Value::integer(random_integer)));
+
+    data.next_action = get_next_action(data);
+
+    false
+}
diff --git a/dust-lang/src/native_function/string.rs b/dust-lang/src/native_function/string.rs
index f368185..8d03c96 100644
--- a/dust-lang/src/native_function/string.rs
+++ b/dust-lang/src/native_function/string.rs
@@ -1,18 +1,13 @@
 use std::ops::Range;
 
 use crate::{
-    vm::{get_next_action, Register, ThreadData},
     ConcreteValue, Value,
+    vm::{Register, ThreadData, get_next_action},
 };
 
-pub fn to_string(
-    data: &mut ThreadData,
-    destination: Option<u8>,
-    argument_range: Range<u8>,
-) -> bool {
+pub fn to_string(data: &mut ThreadData, destination: u8, argument_range: Range<u8>) -> bool {
     let argument_value = data.open_register_unchecked(argument_range.start);
     let argument_string = argument_value.display(data);
-    let destination = destination.unwrap();
     let register = Register::Value(Value::Concrete(ConcreteValue::string(argument_string)));
 
     data.set_register(destination, register);
diff --git a/dust-lang/src/native_function/thread.rs b/dust-lang/src/native_function/thread.rs
new file mode 100644
index 0000000..4786065
--- /dev/null
+++ b/dust-lang/src/native_function/thread.rs
@@ -0,0 +1,64 @@
+use std::{
+    ops::Range,
+    thread::{Builder, JoinHandle},
+};
+
+use tracing::{Level, info, span};
+
+use crate::{
+    DustString,
+    vm::{Thread, ThreadData, get_next_action},
+};
+
+fn start_thread(data: &mut ThreadData, argument_range: Range<u8>) -> JoinHandle<()> {
+    let mut argument_range_iter = argument_range.into_iter();
+    let function_argument = {
+        loop {
+            let register_index = argument_range_iter
+                .next()
+                .unwrap_or_else(|| panic!("No argument was passed to \"spawn\""));
+            let value_option = data.open_register_allow_empty_unchecked(register_index);
+
+            if let Some(argument) = value_option {
+                break argument;
+            }
+        }
+    };
+    let function = function_argument.as_function().unwrap();
+    let prototype_index = function.prototype_index as usize;
+    let current_call = data.call_stack.last_unchecked();
+    let prototype = current_call.chunk.prototypes[prototype_index].clone();
+
+    info!(
+        "Spawning thread for \"{}\"",
+        function
+            .name
+            .as_ref()
+            .cloned()
+            .unwrap_or_else(|| DustString::from("anonymous"))
+    );
+
+    let thread_name = prototype
+        .name
+        .as_ref()
+        .map(|name| name.to_string())
+        .unwrap_or_else(|| "anonymous".to_string());
+    let mut thread = Thread::new(prototype);
+
+    Builder::new()
+        .name(thread_name)
+        .spawn(move || {
+            let span = span!(Level::INFO, "Spawned thread");
+            let _enter = span.enter();
+
+            thread.run();
+        })
+        .expect("Critical VM Error: Failed to spawn thread")
+}
+
+pub fn spawn(data: &mut ThreadData, _: u8, argument_range: Range<u8>) -> bool {
+    let _ = start_thread(data, argument_range);
+    data.next_action = get_next_action(data);
+
+    false
+}
diff --git a/dust-lang/src/value/mod.rs b/dust-lang/src/value/mod.rs
index 6da63fb..6a37fbf 100644
--- a/dust-lang/src/value/mod.rs
+++ b/dust-lang/src/value/mod.rs
@@ -12,7 +12,7 @@ use serde::{Deserialize, Serialize};
 
 use std::fmt::{self, Debug, Display, Formatter};
 
-use crate::{vm::ThreadData, Type};
+use crate::{Type, vm::ThreadData};
 
 #[derive(Clone, Debug, PartialEq, PartialOrd, Serialize, Deserialize)]
 pub enum Value {
@@ -50,9 +50,9 @@ impl Value {
         Value::Concrete(ConcreteValue::String(string.into()))
     }
 
-    pub fn as_boolean(&self) -> Option<&bool> {
-        if let Value::Concrete(ConcreteValue::Boolean(value)) = self {
-            Some(value)
+    pub fn as_boolean(&self) -> Option<bool> {
+        if let Value::Concrete(ConcreteValue::Boolean(boolean)) = self {
+            Some(*boolean)
         } else {
             None
         }
@@ -66,6 +66,14 @@ impl Value {
         }
     }
 
+    pub fn as_integer(&self) -> Option<i64> {
+        if let Value::Concrete(ConcreteValue::Integer(integer)) = self {
+            Some(*integer)
+        } else {
+            None
+        }
+    }
+
     pub fn as_string(&self) -> Option<&DustString> {
         if let Value::Concrete(ConcreteValue::String(value)) = self {
             Some(value)
@@ -74,6 +82,14 @@ impl Value {
         }
     }
 
+    pub fn is_string(&self) -> bool {
+        matches!(self, Value::Concrete(ConcreteValue::String(_)))
+    }
+
+    pub fn is_function(&self) -> bool {
+        matches!(self, Value::Function(_))
+    }
+
     pub fn r#type(&self) -> Type {
         match self {
             Value::Concrete(concrete_value) => concrete_value.r#type(),
diff --git a/dust-lang/src/vm/function_call.rs b/dust-lang/src/vm/function_call.rs
index 86a0991..c9cbe84 100644
--- a/dust-lang/src/vm/function_call.rs
+++ b/dust-lang/src/vm/function_call.rs
@@ -1,29 +1,34 @@
-use std::fmt::{self, Debug, Display, Formatter};
+use std::{
+    fmt::{self, Debug, Display, Formatter},
+    sync::Arc,
+};
 
 use crate::{Chunk, DustString};
 
 use super::Register;
 
 #[derive(Debug)]
-pub struct FunctionCall<'a> {
-    pub chunk: &'a Chunk,
+pub struct FunctionCall {
+    pub chunk: Arc<Chunk>,
     pub ip: usize,
     pub return_register: u8,
     pub registers: Vec<Register>,
 }
 
-impl<'a> FunctionCall<'a> {
-    pub fn new(chunk: &'a Chunk, return_register: u8) -> Self {
+impl FunctionCall {
+    pub fn new(chunk: Arc<Chunk>, return_register: u8) -> Self {
+        let register_count = chunk.register_count;
+
         Self {
             chunk,
             ip: 0,
             return_register,
-            registers: vec![Register::Empty; chunk.register_count],
+            registers: vec![Register::Empty; register_count],
         }
     }
 }
 
-impl Display for FunctionCall<'_> {
+impl Display for FunctionCall {
     fn fmt(&self, f: &mut Formatter) -> fmt::Result {
         write!(
             f,
diff --git a/dust-lang/src/vm/mod.rs b/dust-lang/src/vm/mod.rs
index 4f16b3e..9e0ec9b 100644
--- a/dust-lang/src/vm/mod.rs
+++ b/dust-lang/src/vm/mod.rs
@@ -6,19 +6,20 @@ mod thread;
 
 use std::{
     fmt::{self, Debug, Display, Formatter},
-    sync::mpsc,
-    thread::spawn,
+    sync::Arc,
+    thread::Builder,
 };
 
 pub use function_call::FunctionCall;
-pub(crate) use run_action::get_next_action;
 pub use run_action::RunAction;
+pub(crate) use run_action::get_next_action;
 pub use stack::Stack;
 pub use thread::{Thread, ThreadData};
 
-use tracing::{span, Level};
+use crossbeam_channel::bounded;
+use tracing::{Level, span};
 
-use crate::{compile, Chunk, DustError, Value};
+use crate::{Chunk, DustError, Value, compile};
 
 pub fn run(source: &str) -> Result<Option<Value>, DustError> {
     let chunk = compile(source)?;
@@ -28,41 +29,31 @@ pub fn run(source: &str) -> Result<Option<Value>, DustError> {
 }
 
 pub struct Vm {
-    threads: Vec<Thread>,
+    main_chunk: Chunk,
 }
 
 impl Vm {
-    pub fn new(chunk: Chunk) -> Self {
-        let threads = vec![Thread::new(chunk)];
-
-        debug_assert_eq!(1, threads.capacity());
-
-        Self { threads }
+    pub fn new(main_chunk: Chunk) -> Self {
+        Self { main_chunk }
     }
 
-    pub fn run(mut self) -> Option<Value> {
+    pub fn run(self) -> Option<Value> {
         let span = span!(Level::INFO, "Run");
         let _enter = span.enter();
+        let thread_name = self
+            .main_chunk
+            .name
+            .as_ref()
+            .map(|name| name.to_string())
+            .unwrap_or_else(|| "anonymous".to_string());
+        let mut main_thread = Thread::new(Arc::new(self.main_chunk));
+        let (tx, rx) = bounded(1);
+        let _ = Builder::new().name(thread_name).spawn(move || {
+            let value_option = main_thread.run();
+            let _ = tx.send(value_option);
+        });
 
-        if self.threads.len() == 1 {
-            return self.threads[0].run();
-        }
-
-        let (tx, rx) = mpsc::channel();
-
-        for mut thread in self.threads {
-            let tx = tx.clone();
-
-            spawn(move || {
-                let return_value = thread.run();
-
-                if let Some(value) = return_value {
-                    tx.send(value).unwrap();
-                }
-            });
-        }
-
-        rx.into_iter().last()
+        rx.recv().unwrap()
     }
 }
 
diff --git a/dust-lang/src/vm/run_action.rs b/dust-lang/src/vm/run_action.rs
index 3af2630..5bb6cb4 100644
--- a/dust-lang/src/vm/run_action.rs
+++ b/dust-lang/src/vm/run_action.rs
@@ -1,16 +1,16 @@
 use tracing::trace;
 
 use crate::{
+    AbstractList, Argument, ConcreteValue, Instruction, Type, Value,
     instruction::{
         Add, Call, CallNative, Close, Divide, Equal, GetLocal, Jump, Less, LessEqual, LoadBoolean,
         LoadConstant, LoadFunction, LoadList, LoadSelf, Modulo, Multiply, Negate, Not, Point,
         Return, SetLocal, Subtract, Test, TestSet,
     },
     vm::FunctionCall,
-    AbstractList, Argument, ConcreteValue, Instruction, Type, Value,
 };
 
-use super::{thread::ThreadData, Pointer, Register};
+use super::{Pointer, Register, thread::ThreadData};
 
 #[derive(Clone, Copy, Debug, PartialEq)]
 pub struct RunAction {
@@ -525,14 +525,14 @@ pub fn call(instruction: Instruction, data: &mut ThreadData) -> bool {
     let current_call = data.call_stack.last_unchecked();
     let first_argument_register = return_register - argument_count;
     let prototype = if is_recursive {
-        current_call.chunk
+        current_call.chunk.clone()
     } else {
         let function = data
             .open_register_unchecked(function_register)
             .as_function()
             .unwrap();
 
-        &current_call.chunk.prototypes[function.prototype_index as usize]
+        current_call.chunk.prototypes[function.prototype_index as usize].clone()
     };
     let mut next_call = FunctionCall::new(prototype, return_register);
     let mut argument_index = 0;
@@ -565,7 +565,7 @@ pub fn call_native(instruction: Instruction, data: &mut ThreadData) -> bool {
     let first_argument_index = destination - argument_count;
     let argument_range = first_argument_index..destination;
 
-    function.call(data, Some(destination), argument_range)
+    function.call(data, destination, argument_range)
 }
 
 pub fn r#return(instruction: Instruction, data: &mut ThreadData) -> bool {
diff --git a/dust-lang/src/vm/stack.rs b/dust-lang/src/vm/stack.rs
index ac8d2e9..dd43253 100644
--- a/dust-lang/src/vm/stack.rs
+++ b/dust-lang/src/vm/stack.rs
@@ -124,7 +124,7 @@ impl<T: Debug> Debug for Stack<T> {
     }
 }
 
-impl Display for Stack<FunctionCall<'_>> {
+impl Display for Stack<FunctionCall> {
     fn fmt(&self, f: &mut Formatter) -> fmt::Result {
         writeln!(f, "----- DUST CALL STACK -----")?;
 
diff --git a/dust-lang/src/vm/thread.rs b/dust-lang/src/vm/thread.rs
index 8152a5b..35c9811 100644
--- a/dust-lang/src/vm/thread.rs
+++ b/dust-lang/src/vm/thread.rs
@@ -1,17 +1,17 @@
-use std::mem::replace;
+use std::{mem::replace, sync::Arc, thread::JoinHandle};
 
 use tracing::{info, trace};
 
-use crate::{vm::FunctionCall, Argument, Chunk, DustString, Span, Value};
+use crate::{Argument, Chunk, DustString, Span, Value, vm::FunctionCall};
 
 use super::{Pointer, Register, RunAction, Stack};
 
 pub struct Thread {
-    chunk: Chunk,
+    chunk: Arc<Chunk>,
 }
 
 impl Thread {
-    pub fn new(chunk: Chunk) -> Self {
+    pub fn new(chunk: Arc<Chunk>) -> Self {
         Thread { chunk }
     }
 
@@ -25,7 +25,7 @@ impl Thread {
         );
 
         let mut call_stack = Stack::with_capacity(self.chunk.prototypes.len() + 1);
-        let main_call = FunctionCall::new(&self.chunk, 0);
+        let main_call = FunctionCall::new(self.chunk.clone(), 0);
 
         call_stack.push(main_call);
 
@@ -34,6 +34,7 @@ impl Thread {
             call_stack,
             next_action: first_action,
             return_value_index: None,
+            spawned_threads: Vec::new(),
         };
 
         loop {
@@ -45,7 +46,7 @@ impl Thread {
             );
 
             if should_end {
-                let return_value = if let Some(register_index) = thread_data.return_value_index {
+                let value_option = if let Some(register_index) = thread_data.return_value_index {
                     let value =
                         thread_data.empty_register_or_clone_constant_unchecked(register_index);
 
@@ -54,20 +55,28 @@ impl Thread {
                     None
                 };
 
-                return return_value;
+                thread_data
+                    .spawned_threads
+                    .into_iter()
+                    .for_each(|join_handle| {
+                        let _ = join_handle.join();
+                    });
+
+                return value_option;
             }
         }
     }
 }
 
 #[derive(Debug)]
-pub struct ThreadData<'a> {
-    pub call_stack: Stack<FunctionCall<'a>>,
+pub struct ThreadData {
+    pub call_stack: Stack<FunctionCall>,
     pub next_action: RunAction,
     pub return_value_index: Option<u8>,
+    pub spawned_threads: Vec<JoinHandle<()>>,
 }
 
-impl ThreadData<'_> {
+impl ThreadData {
     pub fn current_position(&self) -> Span {
         let current_call = self.call_stack.last_unchecked();
 
@@ -75,7 +84,7 @@ impl ThreadData<'_> {
     }
 
     pub(crate) fn follow_pointer_unchecked(&self, pointer: Pointer) -> &Value {
-        trace!("Follow pointer {pointer}");
+        trace!("Follow {pointer}");
 
         match pointer {
             Pointer::Register(register_index) => self.open_register_unchecked(register_index),
@@ -97,7 +106,7 @@ impl ThreadData<'_> {
     }
 
     pub fn get_register_unchecked(&self, register_index: u8) -> &Register {
-        trace!("Get register R{register_index}");
+        trace!("Get R{register_index}");
 
         let register_index = register_index as usize;
 
@@ -133,37 +142,25 @@ impl ThreadData<'_> {
             }
         };
 
+        trace!("Open R{register_index} to {register}");
+
         match register {
-            Register::Value(value) => {
-                trace!("Register R{register_index} opened to value {value}");
-
-                value
-            }
-            Register::Pointer(pointer) => {
-                trace!("Open register R{register_index} opened to pointer {pointer}");
-
-                self.follow_pointer_unchecked(*pointer)
-            }
+            Register::Value(value) => value,
+            Register::Pointer(pointer) => self.follow_pointer_unchecked(*pointer),
             Register::Empty => panic!("VM Error: Register {register_index} is empty"),
         }
     }
 
     pub fn open_register_allow_empty_unchecked(&self, register_index: u8) -> Option<&Value> {
-        trace!("Open register R{register_index}");
+        trace!("Open R{register_index}");
 
         let register = self.get_register_unchecked(register_index);
 
+        trace!("Open R{register_index} to {register}");
+
         match register {
-            Register::Value(value) => {
-                trace!("Register R{register_index} openned to value {value}");
-
-                Some(value)
-            }
-            Register::Pointer(pointer) => {
-                trace!("Open register R{register_index} openned to pointer {pointer}");
-
-                Some(self.follow_pointer_unchecked(*pointer))
-            }
+            Register::Value(value) => Some(value),
+            Register::Pointer(pointer) => Some(self.follow_pointer_unchecked(*pointer)),
             Register::Empty => None,
         }
     }
@@ -260,7 +257,7 @@ impl ThreadData<'_> {
 
     pub fn get_local_register(&self, local_index: u8) -> u8 {
         let local_index = local_index as usize;
-        let chunk = self.call_stack.last_unchecked().chunk;
+        let chunk = &self.call_stack.last_unchecked().chunk;
 
         assert!(
             local_index < chunk.locals.len(),