diff --git a/crates/codegen/src/lib.rs b/crates/codegen/src/lib.rs
index 6b17a85..1d926e1 100644
--- a/crates/codegen/src/lib.rs
+++ b/crates/codegen/src/lib.rs
@@ -236,12 +236,26 @@ impl GetRust for TypeExpr {
                 mutable,
                 ty,
             } => {
-                let mutable = if *mutable { "mut " } else { "" };
-
                 if let Some(lifetime) = lifetime {
-                    format!("&'{} {mutable}{}", lifetime.get_rust(), ty.get_rust())
+                    match lifetime {
+                        Lifetime::Lifetime(v) => {
+                            format!(
+                                "&'{} {}{}",
+                                v.get_rust(),
+                                if *mutable { "mut " } else { "" },
+                                ty.get_rust()
+                            )
+                        }
+                        Lifetime::Unsafe => {
+                            format!(
+                                "*{} {}",
+                                if *mutable { "mut" } else { "const" },
+                                ty.get_rust()
+                            )
+                        }
+                    }
                 } else {
-                    format!("&{mutable}{}", ty.get_rust())
+                    format!("&{}{}", if *mutable { "mut " } else { "" }, ty.get_rust())
                 }
             }
 
diff --git a/crates/parser/src/ast/mod.rs b/crates/parser/src/ast/mod.rs
index 28e8cf8..04e6d4b 100644
--- a/crates/parser/src/ast/mod.rs
+++ b/crates/parser/src/ast/mod.rs
@@ -17,10 +17,16 @@ pub struct Identifier(pub String);
 #[derive(Debug, Clone, Serialize, Default)]
 pub struct ParamList(pub Vec<VarDecl>);
 
+#[derive(Debug, Clone, Serialize, PartialEq, Eq, Hash)]
+pub enum Lifetime {
+    Lifetime(Identifier),
+    Unsafe,
+}
+
 #[derive(Debug, Clone, Serialize, PartialEq, Eq, Hash)]
 pub enum TypeExpr {
     Ref {
-        lifetime: Option<Identifier>,
+        lifetime: Option<Lifetime>,
         mutable: bool,
         ty: Box<TypeExpr>,
     },
diff --git a/crates/parser/src/grammar.pest b/crates/parser/src/grammar.pest
index 7a88a2f..5af7c30 100644
--- a/crates/parser/src/grammar.pest
+++ b/crates/parser/src/grammar.pest
@@ -82,6 +82,7 @@ module_program = {
 
 visibility = { "pub" ~ ("(" ~ static_path ~ ")")? }
 mutable    = { "mut" }
+unsafe_kw    = { "unsafe" }
 
 // ======================================================
 // GENERICS
@@ -97,15 +98,17 @@ generics = { "<" ~ (generic ~ ("," ~ generic)*)? ~ ">" }
 // ======================================================
 
 tuple_type = {
-    "[" ~ (type_expr ~ ("," ~ type_expr)*)? ~ ","? ~ "]"
+    "(" ~ (type_expr ~ ("," ~ type_expr)*)? ~ ","? ~ ")"
 }
 
 path_type = {
     static_path ~ generics?
 }
 
+ref_lifetime = { lifetime | unsafe_kw }
+
 ref_type = {
-    "*" ~ lifetime? ~ mutable? ~ type_expr
+    "*" ~ ref_lifetime? ~ mutable? ~ type_expr
 }
 
 dyn_type = {
@@ -142,11 +145,11 @@ multi_pat_template = _{
 }
 
 tuple_pattern = {
-    "[" ~ (pattern | etc_pattern) ~ "," ~ multi_pat_template ~ "]"
+    "(" ~ (pattern | etc_pattern) ~ "," ~ multi_pat_template ~ ")"
 }
 
 named_tuple_pattern = {
-    static_path ~ "[" ~ multi_pat_template ~ "]"
+    static_path ~ "(" ~ multi_pat_template ~ ")"
 }
 
 struct_destruct = {
@@ -330,7 +333,7 @@ trait_decl = {
 override_kw = { "override" ~ ("(" ~ expr_path ~ ")")? }
 
 function_decl = {
-    visibility? ~ override_kw? ~ "fn" ~ identifier ~ generics_decl? ~ "(" ~ method_args ~ ")" ~ type_expr? ~ (block | semicolon)
+    visibility? ~ override_kw? ~ "fn" ~ ("void" | type_expr) ~ identifier ~ generics_decl? ~ "(" ~ method_args ~ ")" ~ (block | semicolon)
 }
 
 // ======================================================
diff --git a/crates/parser/src/parser/common/types.rs b/crates/parser/src/parser/common/types.rs
index fc610f0..3d2fa2b 100644
--- a/crates/parser/src/parser/common/types.rs
+++ b/crates/parser/src/parser/common/types.rs
@@ -28,8 +28,8 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for TypeExpr {
 
             Rule::ref_type => {
                 ast_expr!(TypeExpr::Ref {
-                    lifetime: consume_rule(&mut inner, Rule::lifetime)
-                        .map(|v| v.into_inner().next().map(Identifier::try_from))
+                    lifetime: consume_rule(&mut inner, Rule::ref_lifetime)
+                        .map(|v| v.into_inner().next().map(Lifetime::try_from))
                         .unwrap_or_default()
                         .transpose(),
                     mutable: Ok(listen_rule(&mut inner, Rule::mutable)) as AstResult<bool>,
diff --git a/crates/parser/src/parser/items/function.rs b/crates/parser/src/parser/items/function.rs
index 18b720b..ef37078 100644
--- a/crates/parser/src/parser/items/function.rs
+++ b/crates/parser/src/parser/items/function.rs
@@ -2,7 +2,7 @@ use crate::{
     Rule,
     ast::*,
     ast_ensure, ast_expr,
-    error::{AstError, AstResult, IntoErr},
+    error::{self, AstError, AstResult, IntoErr},
     parser::{consume_rule, listen_rule},
 };
 
@@ -14,6 +14,11 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for FunctionDecl {
         let mut inner = pair.into_inner();
             let visibility = Visibility::try_from(&mut inner);
             let is_override = consume_rule(&mut inner, Rule::override_kw).map(Override::try_from).transpose();
+
+            let return_type = consume_rule(&mut inner, Rule::type_expr)
+                .map(TypeExpr::try_from)
+                .transpose();
+
             let name = Identifier::try_from(inner.next().unwrap());
 
             let generics = consume_rule(&mut inner, Rule::generics_decl)
@@ -34,7 +39,7 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for FunctionDecl {
                     type_: Some(if is_ref {
                         TypeExpr::Ref {
                             lifetime:
-                                lifetime.map(|v| Identifier::try_from(v.into_inner().next().unwrap()))
+                                lifetime.map(|v| Lifetime::try_from(v.into_inner().next().unwrap()))
                                     .transpose()
                                     .expect("Failed to get lifetime identifier"),
                             mutable,
@@ -59,10 +64,6 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for FunctionDecl {
                 })
                 .unwrap_or_else(|| Ok(ParamList(self_param.into_iter().collect())));
 
-            let return_type = consume_rule(&mut inner, Rule::type_expr)
-                .map(TypeExpr::try_from)
-                .transpose();
-
             let body = inner.next().map(Block::try_from).transpose();
 
             ast_expr!(Self {
@@ -87,3 +88,18 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Override {
         })
     }
 }
+
+impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Lifetime {
+    type Error = AstError<'a, Self>;
+
+    fn try_from(pair: pest::iterators::Pair<'a, Rule>) -> Result<Self, Self::Error> {
+        let mut inner = pair.clone().into_inner();
+
+        match pair.as_rule() {
+            Rule::ref_lifetime => inner.next().unwrap().try_into(),
+            Rule::lifetime => ast_expr!(Lifetime::Lifetime(inner.next().unwrap().try_into())),
+            Rule::unsafe_kw => Ok(Lifetime::Unsafe),
+            _ => error::AstError::bug_unimplemented(pair),
+        }
+    }
+}
diff --git a/mist-test/src/common/decl_test.mist b/mist-test/src/common/decl_test.mist
index e9a2e09..d1a1688 100644
--- a/mist-test/src/common/decl_test.mist
+++ b/mist-test/src/common/decl_test.mist
@@ -1,11 +1,11 @@
 pub module decl_test;
 
-pub fn test_let_basic() {
+pub fn void test_let_basic() {
     let x = 42;
     assert_eq!(x, 42);
 }
 
-pub fn test_let_typed() {
+pub fn void test_let_typed() {
     let x i32 = 42;
     assert_eq!(x, 42);
 
@@ -19,57 +19,57 @@ pub fn test_let_typed() {
     assert_eq!(f, 3.14);
 }
 
-pub fn test_let_mut() {
+pub fn void test_let_mut() {
     let mut _x = 42;
     _x = 100;
     assert_eq!(_x, 100);
 }
 
-pub fn test_let_tuple_destructure() {
-    let [a, b] = (10, "hello");
+pub fn void test_let_tuple_destructure() {
+    let (a, b) = (10, "hello");
     assert_eq!(a, 10);
     assert_eq!(b, "hello");
 }
 
-pub fn test_let_nested_tuple() {
-    let [a, [b, c]] = (1, (2, 3));
+pub fn void test_let_nested_tuple() {
+    let (a, (b, c)) = (1, (2, 3));
     assert_eq!(a, 1);
     assert_eq!(b, 2);
     assert_eq!(c, 3);
 }
 
-pub fn test_let_pattern_irrefutable() {
+pub fn void test_let_pattern_irrefutable() {
     let x = 5;
-    let [y, z] = (1, 2);
+    let (y, z) = (1, 2);
     assert_eq!(x, 5);
     assert_eq!(y, 1);
     assert_eq!(z, 2);
 }
 
-pub fn test_multiple_decls() {
+pub fn void test_multiple_decls() {
     let a = 1;
     let b = 2;
     let c = 3;
     assert_eq!(a + b + c, 6);
 }
 
-pub fn test_let_with_type_and_init() {
+pub fn void test_let_with_type_and_init() {
     let x f64 = 10.0;
     assert_eq!(x, 10.0);
 }
 
-pub fn test_string_literal() {
+pub fn void test_string_literal() {
     let s = "hello, world!";
     assert_eq!(s.len(), 13);
 }
 
-pub fn test_let_bool() {
+pub fn void test_let_bool() {
     let t = true;
     let f = false;
     assert_eq!(t, !f);
 }
 
-pub fn run_tests() {
+pub fn void run_tests() {
     test_let_basic();
     test_let_typed();
     test_let_mut();
diff --git a/mist-test/src/common/expr_test.mist b/mist-test/src/common/expr_test.mist
index c7a7cee..88ab9b3 100644
--- a/mist-test/src/common/expr_test.mist
+++ b/mist-test/src/common/expr_test.mist
@@ -1,6 +1,6 @@
 pub module expr_test;
 
-pub fn test_literals() {
+pub fn void test_literals() {
     assert_eq!(42, 42);
     assert_eq!(3.14, 3.14);
     assert_eq!(true, true);
@@ -8,28 +8,28 @@ pub fn test_literals() {
     assert_eq!("hello", "hello");
 }
 
-pub fn test_tuples() {
+pub fn void test_tuples() {
     let t = (1, true, "three");
     assert_eq!(t.0, 1);
     assert_eq!(t.1, true);
     assert_eq!(t.2, "three");
 }
 
-pub fn test_arrays() {
+pub fn void test_arrays() {
     let arr = [1, 2, 3];
     assert_eq!(arr[0], 1);
     assert_eq!(arr[1], 2);
     assert_eq!(arr[2], 3);
 }
 
-pub fn test_array_repeat() {
+pub fn void test_array_repeat() {
     let arr = [0; 5];
     assert_eq!(arr[0], 0);
     assert_eq!(arr[4], 0);
     assert_eq!(arr.len(), 5);
 }
 
-pub fn test_binary_arith() {
+pub fn void test_binary_arith() {
     assert_eq!(10 + 5, 15);
     assert_eq!(10 - 5, 5);
     assert_eq!(10 * 5, 50);
@@ -37,7 +37,7 @@ pub fn test_binary_arith() {
     assert_eq!(10 % 3, 1);
 }
 
-pub fn test_binary_cmp() {
+pub fn void test_binary_cmp() {
     assert_eq!(5 < 10, true);
     assert_eq!(10 <= 10, true);
     assert_eq!(10 > 5, true);
@@ -46,14 +46,14 @@ pub fn test_binary_cmp() {
     assert_eq!(5 != 10, true);
 }
 
-pub fn test_binary_logic() {
+pub fn void test_binary_logic() {
     assert_eq!(true && true, true);
     assert_eq!(true && false, false);
     assert_eq!(true || false, true);
     assert_eq!(false || false, false);
 }
 
-pub fn test_binary_bit() {
+pub fn void test_binary_bit() {
     assert_eq!(5 & 3, 1);
     assert_eq!(5 | 3, 7);
     assert_eq!(5 ^ 3, 6);
@@ -61,20 +61,20 @@ pub fn test_binary_bit() {
     assert_eq!(4 >> 1, 2);
 }
 
-pub fn test_prefix() {
+pub fn void test_prefix() {
     let x = 42;
     assert_eq!(-x, -42);
     assert_eq!(!true, false);
     assert_eq!(!false, true);
 }
 
-pub fn test_ref_deref() {
+pub fn void test_ref_deref() {
     let x = 42;
     let r = &x;
     assert_eq!(*r, 42);
 }
 
-pub fn test_postfix_inc_dec() {
+pub fn void test_postfix_inc_dec() {
     let mut x = 5;
     x++;
     assert_eq!(x, 6);
@@ -82,17 +82,17 @@ pub fn test_postfix_inc_dec() {
     assert_eq!(x, 5);
 }
 
-pub fn test_as_cast() {
+pub fn void test_as_cast() {
     let x = 42;
     assert_eq!(x as f64, 42.0);
 }
 
-pub fn test_closure() {
+pub fn void test_closure() {
     let add = fn(a, b) -> a + b;
     assert_eq!(add(2, 3), 5);
 }
 
-pub fn test_block_expr() {
+pub fn void test_block_expr() {
     let x = {
         let y = 10;
         y + 5
@@ -100,7 +100,7 @@ pub fn test_block_expr() {
     assert_eq!(x, 15);
 }
 
-pub fn test_if_expr() {
+pub fn void test_if_expr() {
     let x = if true { 1 } else { 2 };
     assert_eq!(x, 1);
 
@@ -108,7 +108,7 @@ pub fn test_if_expr() {
     assert_eq!(y, 2);
 }
 
-pub fn test_range_expr() {
+pub fn void test_range_expr() {
     let r = 0..5;
     let mut count = 0;
     for i in r {
@@ -117,7 +117,7 @@ pub fn test_range_expr() {
     assert_eq!(count, 5);
 }
 
-pub fn test_binary_assign() {
+pub fn void test_binary_assign() {
     let mut x = 10;
     x += 5;
     assert_eq!(x, 15);
@@ -131,7 +131,7 @@ pub fn test_binary_assign() {
     assert_eq!(x, 2);
 }
 
-pub fn run_tests() {
+pub fn void run_tests() {
     test_literals();
     test_tuples();
     test_arrays();
diff --git a/mist-test/src/common/package.mist b/mist-test/src/common/package.mist
index b2b6254..324108d 100644
--- a/mist-test/src/common/package.mist
+++ b/mist-test/src/common/package.mist
@@ -1,3 +1,3 @@
 pub module common;
 
-pub fn test_package() {}
+pub fn void test_package() {}
diff --git a/mist-test/src/common/statement_test.mist b/mist-test/src/common/statement_test.mist
index 8829946..ce9a7e9 100644
--- a/mist-test/src/common/statement_test.mist
+++ b/mist-test/src/common/statement_test.mist
@@ -1,6 +1,6 @@
 pub module statement_test;
 
-pub fn test_var_decl() {
+pub fn void test_var_decl() {
     let x = 42;
     assert_eq!(x, 42);
 
@@ -11,13 +11,13 @@ pub fn test_var_decl() {
     assert_eq!(name, "mist");
 }
 
-pub fn test_var_decl_with_init() {
+pub fn void test_var_decl_with_init() {
     let mut x = 0;
     x = 5;
     assert_eq!(x, 5);
 }
 
-pub fn test_if_statement() {
+pub fn void test_if_statement() {
     let mut x = 0;
 
     if true {
@@ -33,7 +33,7 @@ pub fn test_if_statement() {
     assert_eq!(x, 3);
 }
 
-pub fn test_if_else_if() {
+pub fn void test_if_else_if() {
     let mut x = 0;
 
     if x == 1 {
@@ -46,7 +46,7 @@ pub fn test_if_else_if() {
     assert_eq!(x, 20);
 }
 
-pub fn test_while_loop() {
+pub fn void test_while_loop() {
     let mut count = 0;
 
     while count < 5 {
@@ -55,7 +55,7 @@ pub fn test_while_loop() {
     assert_eq!(count, 5);
 }
 
-pub fn test_for_loop() {
+pub fn void test_for_loop() {
     let mut sum = 0;
 
     for i in 0..4 {
@@ -64,7 +64,7 @@ pub fn test_for_loop() {
     assert_eq!(sum, 6);
 }
 
-pub fn test_loop_stmt() {
+pub fn void test_loop_stmt() {
     let mut count = 0;
 
     loop {
@@ -76,7 +76,7 @@ pub fn test_loop_stmt() {
     assert_eq!(count, 3);
 }
 
-pub fn test_break_continue() {
+pub fn void test_break_continue() {
     let mut sum = 0;
 
     for i in 0..10 {
@@ -91,11 +91,11 @@ pub fn test_break_continue() {
     assert_eq!(sum, 1 + 3 + 5);
 }
 
-pub fn test_return_from_fn() i32 {
+pub fn i32 test_return() {
     return 42;
 }
 
-pub fn test_block_scope() {
+pub fn void test_block_scope() {
     let x = {
         let inner = 10;
         inner + 5
@@ -103,7 +103,7 @@ pub fn test_block_scope() {
     assert_eq!(x, 15);
 }
 
-pub fn test_match_literal() {
+pub fn void test_match_literal() {
     let x = 2;
     let result;
 
@@ -116,7 +116,7 @@ pub fn test_match_literal() {
     assert_eq!(result, 20);
 }
 
-pub fn test_match_or_pattern() {
+pub fn void test_match_or_pattern() {
     let x = 1;
     let result i32;
 
@@ -128,7 +128,7 @@ pub fn test_match_or_pattern() {
     assert_eq!(result, 100);
 }
 
-pub fn test_match_default() {
+pub fn void test_match_default() {
     let x = 99;
     let result;
 
@@ -139,17 +139,17 @@ pub fn test_match_default() {
     assert_eq!(result, 99);
 }
 
-pub fn test_for_with_pattern_destructure() {
+pub fn void test_for_with_pattern_destructure() {
     let pairs = [(1, "a"), (2, "b")];
     let mut keys = 0;
 
-    for [k, _] in pairs {
+    for (k, _) in pairs {
         keys += k;
     }
     assert_eq!(keys, 3);
 }
 
-pub fn run_tests() {
+pub fn void run_tests() {
     test_var_decl();
     test_var_decl_with_init();
     test_if_statement();
@@ -158,7 +158,7 @@ pub fn run_tests() {
     test_for_loop();
     test_loop_stmt();
     test_break_continue();
-    assert_eq!(test_return_from_fn(), 42);
+    assert_eq!(test_return(), 42);
     test_block_scope();
     test_match_literal();
     test_match_or_pattern();
diff --git a/mist-test/src/common/types_test.mist b/mist-test/src/common/types_test.mist
index 8edf714..eaf2cf4 100644
--- a/mist-test/src/common/types_test.mist
+++ b/mist-test/src/common/types_test.mist
@@ -1,16 +1,16 @@
 pub module types_test;
 
-pub fn test_integer_type() {
+pub fn void test_integer_type() {
     let x i32 = 42;
     assert_eq!(x, 42);
 }
 
-pub fn test_float_type() {
+pub fn void test_float_type() {
     let x f64 = 3.14;
     assert_eq!(x, 3.14);
 }
 
-pub fn test_bool_type() {
+pub fn void test_bool_type() {
     let x bool = true;
     assert_eq!(x, true);
 
@@ -18,41 +18,41 @@ pub fn test_bool_type() {
     assert_eq!(y, false);
 }
 
-pub fn test_string_type() {
+pub fn void test_string_type() {
     let s *str = "hello";
     assert_eq!(s, "hello");
 }
 
-pub fn test_tuple_type() {
-    let t [i32, *str] = (42, "answer");
+pub fn void test_tuple_type() {
+    let t (i32, *str) = (42, "answer");
     assert_eq!(t.0, 42);
     assert_eq!(t.1, "answer");
 }
 
-pub fn test_ref_type() {
+pub fn void test_ref_type() {
     let x i32 = 42;
     let r *i32 = &x;
     assert_eq!(*r, 42);
 }
 
-pub fn test_mut_ref_type() {
+pub fn void test_mut_ref_type() {
     let mut x = 42;
     let r *mut i32 = &mut x;
     *r = 100;
     assert_eq!(x, 100);
 }
 
-pub fn test_void_type() {}
+pub fn void test_void_type() {}
 
-fn add(a i32, b i32) i32 {
+fn i32 add(a i32, b i32) {
     a + b
 }
 
-pub fn test_fn_return_type() {
+pub fn void test_fn_return_type() {
     assert_eq!(add(3, 4), 7);
 }
 
-pub fn run_tests() {
+pub fn void run_tests() {
     test_integer_type();
     test_float_type();
     test_bool_type();
diff --git a/mist-test/src/items/attribute_test.mist b/mist-test/src/items/attribute_test.mist
index 09f76f2..5363dd1 100644
--- a/mist-test/src/items/attribute_test.mist
+++ b/mist-test/src/items/attribute_test.mist
@@ -5,19 +5,19 @@ pub struct Debuggable {
     value i32,
 }
 
-pub fn test_derive_attribute() {
+pub fn void test_derive_attribute() {
     let d = Debuggable { value: 42 };
     assert_eq!(d.value, 42);
 }
 
 #[allow(unused_variables)]
-pub fn test_allow_attribute() {
+pub fn void test_allow_attribute() {
     let x = 42;
     let y = "unused";
     assert_eq!(x, 42);
 }
 
-pub fn run_tests() {
+pub fn void run_tests() {
     test_derive_attribute();
     test_allow_attribute();
 }
diff --git a/mist-test/src/items/class_test.mist b/mist-test/src/items/class_test.mist
index 8c441e4..a95c15a 100644
--- a/mist-test/src/items/class_test.mist
+++ b/mist-test/src/items/class_test.mist
@@ -8,15 +8,15 @@ pub class Animal<T> {
         self.name = "Rex".to_string();
     }
 
-    pub fn speak(*self) {
-        println!("Unknown");
+    pub fn String speak(*self) {
+        "Unknown".to_string()
     }
 
-    pub fn test_speak(*self) {
-        self.speak();
+    pub fn void test_speak(*self) {
+        assert_eq!(self.speak(), "Woof!");
     }
 
-    pub fn static_method() {}
+    pub fn void static_method() {}
 }
 
 pub class Mammal<T> : Animal<T> {
@@ -24,10 +24,9 @@ pub class Mammal<T> : Animal<T> {
         super = Super::new();
     }
 
-    pub fn args_test(*self, x i32, y *str) {}
-
-    pub fn returning<'a>(*self) *'a str {
-        "Mammal"
+    pub fn void args_test(*self, x i32, y *str) {
+        assert_eq!(x, 10);
+        assert_eq!(y, "hello");
     }
 }
 
@@ -36,21 +35,23 @@ pub class Dog : Mammal<i32> {
         super = Super::new();
     }
 
-    pub override(Animal<i32>) fn speak(*self) {
-        println!("Woof!");
+    pub override(Animal<i32>) fn String speak(*self) {
+        "Woof!".to_string()
     }
 
-    pub override fn returning(*self) *str {
-        "Dog"
+    impl std::fmt::Display {
+        fn Result<(), std::fmt::Error> fmt(*self, f *mut std::fmt::Formatter<'_>) {
+            write!(f, "🐾 {}", self.name)
+        }
     }
 }
 
-pub fn run_tests() {
+pub fn void run_tests() {
     let dawg = Dog::new();
 
     dawg.args_test(10, "hello");
 
     dawg.test_speak();
 
-    println!("{}", dawg.returning());
+    assert_eq!(format!("{dawg}"), "🐾 Rex");
 }
diff --git a/mist-test/src/items/enum_test.mist b/mist-test/src/items/enum_test.mist
index a005f46..db6c763 100644
--- a/mist-test/src/items/enum_test.mist
+++ b/mist-test/src/items/enum_test.mist
@@ -2,22 +2,22 @@ pub module enum_test;
 
 enum OptionInt {
     None,
-    Some[i32],
+    Some(i32),
 }
 
-pub fn test_enum_named() {
+pub fn void test_enum_named() {
     let x = OptionInt::None;
     match x {
         OptionInt::None => { assert_eq!(1, 1); }
-        OptionInt::Some[_] => { assert_eq!(0, 1); }
+        OptionInt::Some(_) => { assert_eq!(0, 1); }
     }
 }
 
-pub fn test_enum_tuple() {
+pub fn void test_enum_tuple() {
     let x = OptionInt::Some(42);
     match x {
         OptionInt::None => { assert_eq!(0, 1); }
-        OptionInt::Some[v] => { assert_eq!(v, 42); }
+        OptionInt::Some(v) => { assert_eq!(v, 42); }
     }
 }
 
@@ -26,7 +26,7 @@ enum Shape {
     Rect { w i32, h i32 },
 }
 
-pub fn test_enum_struct() {
+pub fn void test_enum_struct() {
     let c = Shape::Circle { radius: 5 };
     match c {
         Shape::Circle { radius } => { assert_eq!(radius, 5); }
@@ -46,7 +46,7 @@ enum Color {
     Blue,
 }
 
-pub fn test_enum_eq() {
+pub fn void test_enum_eq() {
     let c = Color::Red;
     match c {
         Color::Red => { assert_eq!(1, 1); }
@@ -54,7 +54,7 @@ pub fn test_enum_eq() {
     }
 }
 
-pub fn run_tests() {
+pub fn void run_tests() {
     test_enum_named();
     test_enum_tuple();
     test_enum_struct();
diff --git a/mist-test/src/items/function_test.mist b/mist-test/src/items/function_test.mist
index 8cbcb21..3cec722 100644
--- a/mist-test/src/items/function_test.mist
+++ b/mist-test/src/items/function_test.mist
@@ -1,60 +1,60 @@
 pub module function_test;
 
-fn greet() {
+fn void greet() {
     let mut x = 1;
     x++;
 }
 
-pub fn test_basic_function() {
+pub fn void test_basic_function() {
     greet();
 }
 
-fn add(a i32, b i32) i32 {
+fn i32 add(a i32, b i32) {
     a + b
 }
 
-pub fn test_fn_params() {
+pub fn void test_fn_params() {
     assert_eq!(add(2, 3), 5);
 }
 
-pub fn test_fn_return() i32 {
+pub fn i32 test_fn_return() {
     42
 }
 
-pub fn test_fn_early_return() i32 {
+pub fn i32 test_fn_early_return() {
     return 100;
     0
 }
 
-pub fn test_fn_mut_param(mut x i32) i32 {
+pub fn i32 test_fn_mut_param(mut x i32) {
     x = x + 10;
     x
 }
 
-pub fn test_method_call() {
+pub fn void test_method_call() {
     let s = "hello";
     assert_eq!(s.len(), 5);
     assert_eq!(s.to_uppercase(), "HELLO");
 }
 
-fn triple(x i32) i32 {
+fn i32 triple(x i32) {
     add(x, add(x, x))
 }
 
-pub fn test_nested_fn_calls() {
+pub fn void test_nested_fn_calls() {
     assert_eq!(triple(5), 15);
 }
 
-fn factorial(n i32) i32 {
+fn i32 factorial(n i32) {
     if n <= 1 { 1 }
     else { n * factorial(n - 1) }
 }
 
-pub fn test_recursive_fn() {
+pub fn void test_recursive_fn() {
     assert_eq!(factorial(5), 120);
 }
 
-pub fn run_tests() {
+pub fn void run_tests() {
     test_basic_function();
     test_fn_params();
     assert_eq!(test_fn_return(), 42);
diff --git a/mist-test/src/items/impl_test.mist b/mist-test/src/items/impl_test.mist
index 2c9b50a..68d0ed6 100644
--- a/mist-test/src/items/impl_test.mist
+++ b/mist-test/src/items/impl_test.mist
@@ -6,34 +6,34 @@ struct Vector2 {
 }
 
 impl Vector2 {
-    pub fn magnitude(*self) i32 {
+    pub fn i32 magnitude(*self) {
         self.x * self.x + self.y * self.y
     }
 }
 
-pub fn test_inherent_impl() {
+pub fn void test_inherent_impl() {
     let v = Vector2 { x: 3, y: 4 };
     assert_eq!(v.magnitude(), 25);
 }
 
 trait Display {
-    fn display(*self) String;
+    fn String display(*self);
 }
 
 impl Display for Vector2 {
-    fn display(*self) String {
+    fn String display(*self) {
         format!("({}, {})", self.x, self.y)
     }
 }
 
-pub fn test_trait_impl_block() {
+pub fn void test_trait_impl_block() {
     let v = Vector2 { x: 1, y: 2 };
     let s = v.display();
     assert_eq!(s.len() > 0, true);
 }
 
 impl Vector2 {
-    pub fn add(*self, other Vector2) Vector2 {
+    pub fn Vector2 add(*self, other Vector2) {
         Vector2 {
             x: self.x + other.x,
             y: self.y + other.y,
@@ -41,7 +41,7 @@ impl Vector2 {
     }
 }
 
-pub fn test_multiple_impls() {
+pub fn void test_multiple_impls() {
     let a = Vector2 { x: 1, y: 2 };
     let b = Vector2 { x: 3, y: 4 };
     let c = a.add(b);
@@ -49,7 +49,7 @@ pub fn test_multiple_impls() {
     assert_eq!(c.y, 6);
 }
 
-pub fn run_tests() {
+pub fn void run_tests() {
     test_inherent_impl();
     test_trait_impl_block();
     test_multiple_impls();
diff --git a/mist-test/src/items/struct_test.mist b/mist-test/src/items/struct_test.mist
index bd83f6b..d5e27b1 100644
--- a/mist-test/src/items/struct_test.mist
+++ b/mist-test/src/items/struct_test.mist
@@ -5,19 +5,19 @@ struct Point {
     y i32,
 }
 
-pub fn test_struct_create_access() {
+pub fn void test_struct_create_access() {
     let p = Point { x: 10, y: 20 };
     assert_eq!(p.x, 10);
     assert_eq!(p.y, 20);
 }
 
-pub fn test_struct_mut_field() {
+pub fn void test_struct_mut_field() {
     let mut p = Point { x: 1, y: 2 };
     p.x = 100;
     assert_eq!(p.x, 100);
 }
 
-pub fn test_struct_destructure() {
+pub fn void test_struct_destructure() {
     let p = Point { x: 3, y: 4 };
     let Point { x, y } = p;
     assert_eq!(x, 3);
@@ -29,7 +29,7 @@ struct Line {
     end Point,
 }
 
-pub fn test_struct_nested() {
+pub fn void test_struct_nested() {
     let l = Line {
         start: Point { x: 0, y: 0 },
         end: Point { x: 5, y: 10 },
@@ -38,7 +38,7 @@ pub fn test_struct_nested() {
     assert_eq!(l.end.y, 10);
 }
 
-pub fn run_tests() {
+pub fn void run_tests() {
     test_struct_create_access();
     test_struct_mut_field();
     test_struct_destructure();
diff --git a/mist-test/src/items/trait_test.mist b/mist-test/src/items/trait_test.mist
index 41fe093..4e7a2bf 100644
--- a/mist-test/src/items/trait_test.mist
+++ b/mist-test/src/items/trait_test.mist
@@ -1,11 +1,11 @@
 pub module trait_test;
 
 trait Speak {
-    fn speak(*self) String;
+    fn String speak(*self);
 }
 
 trait Greet : Speak {
-    fn greet(*self) String;
+    fn String greet(*self);
 }
 
 struct Dog {
@@ -13,29 +13,29 @@ struct Dog {
 }
 
 impl Speak for Dog {
-    fn speak(*self) String {
+    fn String speak(*self) {
         "woof".to_string()
     }
 }
 
 impl Greet for Dog {
-    fn greet(*self) String {
+    fn String greet(*self) {
         "hello".to_string()
     }
 }
 
-pub fn test_trait_impl() {
+pub fn void test_trait_impl() {
     let d = Dog { name: "Rex".to_string() };
     assert_eq!(d.speak(), "woof");
 }
 
-pub fn test_trait_with_requirement() {
+pub fn void test_trait_with_requirement() {
     let d = Dog { name: "Buddy".to_string() };
     assert_eq!(d.speak(), "woof");
     assert_eq!(d.greet(), "hello");
 }
 
-pub fn run_tests() {
+pub fn void run_tests() {
     test_trait_impl();
     test_trait_with_requirement();
 }
diff --git a/mist-test/src/main.mist b/mist-test/src/main.mist
index 6bf0069..0025a0c 100644
--- a/mist-test/src/main.mist
+++ b/mist-test/src/main.mist
@@ -1,4 +1,4 @@
-fn main() {
+fn void main() {
     println!("running common tests...");
     common::test_package();
     common::expr_test::run_tests();
@@ -16,4 +16,4 @@ fn main() {
     items::attribute_test::run_tests();
 
     println!("\x1b[32m\nAll tests passed!\x1b[0m");
-}
\ No newline at end of file
+}