diff --git a/example/program.nub b/example/program.nub
index 46dcf7e..4d02d13 100644
--- a/example/program.nub
+++ b/example/program.nub
@@ -1,4 +1,4 @@
-import "c";
+import c;
 
 global func main() {
     printf("something %s\n", "your mom");
diff --git a/src/compiler/.idea/.idea.Nub.Lang/.idea/vcs.xml b/src/compiler/.idea/.idea.Nub.Lang/.idea/vcs.xml
index 64713b8..b2bdec2 100644
--- a/src/compiler/.idea/.idea.Nub.Lang/.idea/vcs.xml
+++ b/src/compiler/.idea/.idea.Nub.Lang/.idea/vcs.xml
@@ -2,6 +2,5 @@
 <project version="4">
   <component name="VcsDirectoryMappings">
     <mapping directory="$PROJECT_DIR$/../.." vcs="Git" />
-    <mapping directory="$PROJECT_DIR$/.." vcs="Git" />
   </component>
 </project>
\ No newline at end of file
diff --git a/src/compiler/Nub.Lang/Backend/Generator.cs b/src/compiler/Nub.Lang/Backend/Generator.cs
index 9c528a8..517b9fc 100644
--- a/src/compiler/Nub.Lang/Backend/Generator.cs
+++ b/src/compiler/Nub.Lang/Backend/Generator.cs
@@ -44,22 +44,64 @@ public class Generator
 
     private string QbeTypeName(NubType type)
     {
-        if (type.Equals(NubType.Int32) || type.Equals(NubType.Bool))
+        if (type is NubPrimitiveType primitiveType)
         {
-            return "w";
+            switch (primitiveType.Kind)
+            {
+                case PrimitiveTypeKind.I64:
+                case PrimitiveTypeKind.U64:
+                case PrimitiveTypeKind.String:
+                case PrimitiveTypeKind.Any:
+                    return "l";
+                case PrimitiveTypeKind.I32:
+                case PrimitiveTypeKind.U32:
+                case PrimitiveTypeKind.I16:
+                case PrimitiveTypeKind.U16:
+                case PrimitiveTypeKind.I8:
+                case PrimitiveTypeKind.U8:
+                case PrimitiveTypeKind.Bool:
+                    return "w";
+                case PrimitiveTypeKind.F64:
+                    return "d";
+                case PrimitiveTypeKind.F32:
+                    return "s";
+                default:
+                    throw new ArgumentOutOfRangeException();
+            }
         }
 
-        return "l";
+        throw new NotImplementedException();
     }
 
     private int QbeTypeSize(NubType type)
     {
-        if (type.Equals(NubType.Int32) || type.Equals(NubType.Bool))
+        if (type is NubPrimitiveType primitiveType)
         {
-            return 4;
+            switch (primitiveType.Kind)
+            {
+                case PrimitiveTypeKind.I64:
+                case PrimitiveTypeKind.U64:
+                case PrimitiveTypeKind.String:
+                case PrimitiveTypeKind.Any:
+                    return 8;
+                case PrimitiveTypeKind.I32:
+                case PrimitiveTypeKind.U32:
+                case PrimitiveTypeKind.I16:
+                case PrimitiveTypeKind.U16:
+                case PrimitiveTypeKind.I8:
+                case PrimitiveTypeKind.U8:
+                case PrimitiveTypeKind.Bool:
+                    return 4;
+                case PrimitiveTypeKind.F64:
+                    return 8;
+                case PrimitiveTypeKind.F32:
+                    return 4;
+                default:
+                    throw new ArgumentOutOfRangeException();
+            }
         }
 
-        return 8;
+        throw new NotImplementedException();
     }
 
     private void GenerateFuncDefinition(LocalFuncDefinitionNode node)
@@ -349,25 +391,25 @@ public class Generator
         {
             case BinaryExpressionOperator.Equal:
             {
-                if (binaryExpression.Left.Type.Equals(NubType.Int64) && binaryExpression.Right.Type.Equals(NubType.Int64))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I64))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w ceql {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Int32) && binaryExpression.Right.Type.Equals(NubType.Int32))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I32))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w ceqw {left}, {right}");
                     return $"%{outputLabel}";
                 }
 
-                if (binaryExpression.Left.Type.Equals(NubType.String) && binaryExpression.Right.Type.Equals(NubType.String))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.String))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w call $nub_strcmp(l {left}, l {right})");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Bool) && binaryExpression.Right.Type.Equals(NubType.Bool))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.Bool))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w ceqw {left}, {right}");
                     return $"%{outputLabel}";
@@ -376,26 +418,26 @@ public class Generator
             }
             case BinaryExpressionOperator.NotEqual:
             {
-                if (binaryExpression.Left.Type.Equals(NubType.Int64) && binaryExpression.Right.Type.Equals(NubType.Int64))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I64))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w cnel {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Int32) && binaryExpression.Right.Type.Equals(NubType.Int32))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I32))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w cnew {left}, {right}");
                     return $"%{outputLabel}";
                 }
 
-                if (binaryExpression.Left.Type.Equals(NubType.String) && binaryExpression.Right.Type.Equals(NubType.String))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.String))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w call $nub_strcmp(l {left}, l {right})");
                     _builder.AppendLine($"    %{outputLabel} =w xor %{outputLabel}, 1");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Bool) && binaryExpression.Right.Type.Equals(NubType.Bool))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.Bool))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w cnew {left}, {right}");
                     return $"%{outputLabel}";
@@ -404,19 +446,19 @@ public class Generator
             }
             case BinaryExpressionOperator.GreaterThan:
             {
-                if (binaryExpression.Left.Type.Equals(NubType.Int64) && binaryExpression.Right.Type.Equals(NubType.Int64))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I64))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w csgtl {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Int32) && binaryExpression.Right.Type.Equals(NubType.Int32))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I32))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w csgtw {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Bool) && binaryExpression.Right.Type.Equals(NubType.Bool))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.Bool))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w csgtw {left}, {right}");
                     return $"%{outputLabel}";
@@ -425,19 +467,19 @@ public class Generator
             }
             case BinaryExpressionOperator.GreaterThanOrEqual:
             {
-                if (binaryExpression.Left.Type.Equals(NubType.Int64) && binaryExpression.Right.Type.Equals(NubType.Int64))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I64))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w csgel {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Int32) && binaryExpression.Right.Type.Equals(NubType.Int32))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I32))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w csgew {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Bool) && binaryExpression.Right.Type.Equals(NubType.Bool))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.Bool))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w csgew {left}, {right}");
                     return $"%{outputLabel}";
@@ -446,19 +488,19 @@ public class Generator
             }
             case BinaryExpressionOperator.LessThan:
             {
-                if (binaryExpression.Left.Type.Equals(NubType.Int64) && binaryExpression.Right.Type.Equals(NubType.Int64))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I64))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w csltl {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Int32) && binaryExpression.Right.Type.Equals(NubType.Int32))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I32))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w csltw {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Bool) && binaryExpression.Right.Type.Equals(NubType.Bool))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.Bool))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w csltw {left}, {right}");
                     return $"%{outputLabel}";
@@ -467,19 +509,19 @@ public class Generator
             }
             case BinaryExpressionOperator.LessThanOrEqual:
             {
-                if (binaryExpression.Left.Type.Equals(NubType.Int64) && binaryExpression.Right.Type.Equals(NubType.Int64))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I64))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w cslel {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Int32) && binaryExpression.Right.Type.Equals(NubType.Int32))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I32))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w cslew {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Bool) && binaryExpression.Right.Type.Equals(NubType.Bool))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.Bool))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w cslew {left}, {right}");
                     return $"%{outputLabel}";
@@ -488,13 +530,13 @@ public class Generator
             }
             case BinaryExpressionOperator.Plus:
             {
-                if (binaryExpression.Left.Type.Equals(NubType.Int64) && binaryExpression.Right.Type.Equals(NubType.Int64))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I64))
                 {
                     _builder.AppendLine($"    %{outputLabel} =l add {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Int32) && binaryExpression.Right.Type.Equals(NubType.Int32))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I32))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w add {left}, {right}");
                     return $"%{outputLabel}";
@@ -503,13 +545,13 @@ public class Generator
             }
             case BinaryExpressionOperator.Minus:
             {
-                if (binaryExpression.Left.Type.Equals(NubType.Int64) && binaryExpression.Right.Type.Equals(NubType.Int64))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I64))
                 {
                     _builder.AppendLine($"    %{outputLabel} =l sub {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Int32) && binaryExpression.Right.Type.Equals(NubType.Int32))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I32))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w sub {left}, {right}");
                     return $"%{outputLabel}";
@@ -518,13 +560,13 @@ public class Generator
             }
             case BinaryExpressionOperator.Multiply:
             {
-                if (binaryExpression.Left.Type.Equals(NubType.Int64) && binaryExpression.Right.Type.Equals(NubType.Int64))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I64))
                 {
                     _builder.AppendLine($"    %{outputLabel} =l mul {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Int32) && binaryExpression.Right.Type.Equals(NubType.Int32))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I32))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w mul {left}, {right}");
                     return $"%{outputLabel}";
@@ -533,13 +575,13 @@ public class Generator
             }
             case BinaryExpressionOperator.Divide:
             {
-                if (binaryExpression.Left.Type.Equals(NubType.Int64) && binaryExpression.Right.Type.Equals(NubType.Int64))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I64))
                 {
                     _builder.AppendLine($"    %{outputLabel} =l div {left}, {right}");
                     return $"%{outputLabel}";
                 }
                 
-                if (binaryExpression.Left.Type.Equals(NubType.Int32) && binaryExpression.Right.Type.Equals(NubType.Int32))
+                if (binaryExpression.Left.Type.Equals(NubPrimitiveType.I32))
                 {
                     _builder.AppendLine($"    %{outputLabel} =w div {left}, {right}");
                     return $"%{outputLabel}";
@@ -562,18 +604,18 @@ public class Generator
 
     private string GenerateLiteral(LiteralNode literal)
     {
-        if (literal.LiteralType.Equals(NubType.String))
+        if (literal.LiteralType.Equals(NubPrimitiveType.String))
         {
             _strings.Add(literal.Literal);
             return $"$str{_strings.Count}";
         }
 
-        if (literal.LiteralType.Equals(NubType.Int64) || literal.LiteralType.Equals(NubType.Int32))
+        if (literal.LiteralType.Equals(NubPrimitiveType.I64) || literal.LiteralType.Equals(NubPrimitiveType.I32))
         {
             return literal.Literal;
         }
 
-        if (literal.LiteralType.Equals(NubType.Bool))
+        if (literal.LiteralType.Equals(NubPrimitiveType.Bool))
         {
             return bool.Parse(literal.Literal) ? "1" : "0";
         }
diff --git a/src/compiler/Nub.Lang/Frontend/Lexing/Lexer.cs b/src/compiler/Nub.Lang/Frontend/Lexing/Lexer.cs
index ed15a4d..cbf544e 100644
--- a/src/compiler/Nub.Lang/Frontend/Lexing/Lexer.cs
+++ b/src/compiler/Nub.Lang/Frontend/Lexing/Lexer.cs
@@ -86,7 +86,7 @@ public class Lexer
             
             if (buffer is "true" or "false")
             {
-                return new LiteralToken(NubType.Bool, buffer);
+                return new LiteralToken(NubPrimitiveType.Bool, buffer);
             }
 
             return new IdentifierToken(buffer);
@@ -103,7 +103,7 @@ public class Lexer
                 current = Peek();
             }
 
-            return new LiteralToken(NubType.Int64, buffer);
+            return new LiteralToken(NubPrimitiveType.I64, buffer);
         }
 
         // TODO: Revisit this
@@ -148,7 +148,7 @@ public class Lexer
                 buffer += current.Value;
             }
             
-            return new LiteralToken(NubType.String, buffer);
+            return new LiteralToken(NubPrimitiveType.String, buffer);
         }
 
         if (char.IsWhiteSpace(current.Value))
diff --git a/src/compiler/Nub.Lang/Frontend/Parsing/Parser.cs b/src/compiler/Nub.Lang/Frontend/Parsing/Parser.cs
index 59e8f8b..45567a4 100644
--- a/src/compiler/Nub.Lang/Frontend/Parsing/Parser.cs
+++ b/src/compiler/Nub.Lang/Frontend/Parsing/Parser.cs
@@ -20,12 +20,7 @@ public class Parser
         {
             if (TryExpectSymbol(Symbol.Import))
             {
-                var name = ExpectLiteral();
-                if (!name.Type.Equals(NubType.String))
-                {
-                    throw new Exception("Import statements must have a string literal value");
-                }
-
+                var name = ExpectIdentifier();
                 TryExpectSymbol(Symbol.Semicolon);
                 imports.Add(name.Value);
             }
@@ -466,7 +461,7 @@ public class Parser
     private NubType ParseType()
     {
         var name = ExpectIdentifier().Value;
-        return new NubType(name);
+        return NubType.Parse(name);
     }
 
     private Token ExpectToken()
diff --git a/src/compiler/Nub.Lang/Frontend/Typing/ExpressionTyper.cs b/src/compiler/Nub.Lang/Frontend/Typing/ExpressionTyper.cs
index 63e8ebc..14e2f64 100644
--- a/src/compiler/Nub.Lang/Frontend/Typing/ExpressionTyper.cs
+++ b/src/compiler/Nub.Lang/Frontend/Typing/ExpressionTyper.cs
@@ -197,7 +197,7 @@ public class ExpressionTyper
             case BinaryExpressionOperator.LessThan:
             case BinaryExpressionOperator.LessThanOrEqual:
             {
-                binaryExpression.Type = new NubType("bool");
+                binaryExpression.Type = NubPrimitiveType.Bool;
                 break;
             }
             case BinaryExpressionOperator.Plus:
diff --git a/src/compiler/Nub.Lang/NubType.cs b/src/compiler/Nub.Lang/NubType.cs
index 866881e..6e580a3 100644
--- a/src/compiler/Nub.Lang/NubType.cs
+++ b/src/compiler/Nub.Lang/NubType.cs
@@ -1,32 +1,117 @@
-namespace Nub.Lang;
+using System.Diagnostics.CodeAnalysis;
 
-public sealed class NubType
+namespace Nub.Lang;
+
+public abstract class NubType
 {
-    public NubType(string name)
+    protected NubType(string name)
     {
         Name = name;
     }
 
     public string Name { get; }
 
-    public static NubType Int64 => new("i64");
-    public static NubType Int32 => new("i32");
-    public static NubType Bool => new("bool");
-    public static NubType String => new("string");
-    public static NubType Any => new("any");
-
-    public override bool Equals(object? obj)
+    public static NubType Parse(string s)
     {
-        return obj is NubType item && Name.Equals(item.Name);
+        if (NubPrimitiveType.TryParse(s, out var kind))
+        {
+            return new NubPrimitiveType(kind.Value);
+        }
+
+        return new NubCustomType(s);
     }
 
-    public override int GetHashCode()
+    public override bool Equals(object? obj) => obj is NubType item && Name.Equals(item.Name);
+    public override int GetHashCode() => HashCode.Combine(Name);
+    public override string ToString() => Name;
+}
+
+public class NubCustomType(string name) : NubType(name);
+
+public class NubPrimitiveType : NubType
+{
+    public NubPrimitiveType(PrimitiveTypeKind kind) : base(KindToString(kind))
     {
-        return HashCode.Combine(Name);
+        Kind = kind;
     }
 
-    public override string ToString()
+    public PrimitiveTypeKind Kind { get; }
+
+    public static NubPrimitiveType I64 => new(PrimitiveTypeKind.I64);
+    public static NubPrimitiveType I32 => new(PrimitiveTypeKind.I32);
+    public static NubPrimitiveType I16 => new(PrimitiveTypeKind.I16);
+    public static NubPrimitiveType I8 => new(PrimitiveTypeKind.I8);
+    
+    public static NubPrimitiveType U64 => new(PrimitiveTypeKind.U64);
+    public static NubPrimitiveType U32 => new(PrimitiveTypeKind.U32);
+    public static NubPrimitiveType U16 => new(PrimitiveTypeKind.U16);
+    public static NubPrimitiveType U8 => new(PrimitiveTypeKind.U8);
+    
+    public static NubPrimitiveType F64 => new(PrimitiveTypeKind.F64);
+    public static NubPrimitiveType F32 => new(PrimitiveTypeKind.F32);
+    
+    public static NubPrimitiveType Bool => new(PrimitiveTypeKind.Bool);
+    public static NubPrimitiveType String => new(PrimitiveTypeKind.String);
+    public static NubPrimitiveType Any => new(PrimitiveTypeKind.Any);
+
+    public static bool TryParse(string s, [NotNullWhen(true)] out PrimitiveTypeKind? kind)
     {
-        return $"{Name}";
+        kind = s switch
+        {
+            "i64" => PrimitiveTypeKind.I64,
+            "i32" => PrimitiveTypeKind.I32,
+            "i16" => PrimitiveTypeKind.I16,
+            "i8" => PrimitiveTypeKind.I8,
+            "u64" => PrimitiveTypeKind.U64,
+            "u32" => PrimitiveTypeKind.U32,
+            "u16" => PrimitiveTypeKind.U16,
+            "u8" => PrimitiveTypeKind.U8,
+            "f64" => PrimitiveTypeKind.F64,
+            "f32" => PrimitiveTypeKind.F32,
+            "bool" => PrimitiveTypeKind.Bool,
+            "string" => PrimitiveTypeKind.String,
+            "any" => PrimitiveTypeKind.Any,
+            _ => null
+        };
+
+        return kind != null;
     }
+
+    public static string KindToString(PrimitiveTypeKind kind)
+    {
+        return kind switch
+        {
+            PrimitiveTypeKind.I64 => "i64",
+            PrimitiveTypeKind.I32 => "i32",
+            PrimitiveTypeKind.I16 => "i16",
+            PrimitiveTypeKind.I8 => "i8",
+            PrimitiveTypeKind.U64 => "u64",
+            PrimitiveTypeKind.U32 => "u32",
+            PrimitiveTypeKind.U16 => "u16",
+            PrimitiveTypeKind.U8 => "u8",
+            PrimitiveTypeKind.F64 => "f64",
+            PrimitiveTypeKind.F32 => "f32",
+            PrimitiveTypeKind.Bool => "bool",
+            PrimitiveTypeKind.String => "string",
+            PrimitiveTypeKind.Any => "any",
+            _ => throw new ArgumentOutOfRangeException(nameof(kind), kind, null)
+        };
+    }
+}
+
+public enum PrimitiveTypeKind
+{
+    I64,
+    I32,
+    I16,
+    I8,
+    U64,
+    U32,
+    U16,
+    U8,
+    F64,
+    F32,
+    Bool,
+    String,
+    Any
 }
\ No newline at end of file
diff --git a/src/runtime/gc.c b/src/runtime/gc.c
deleted file mode 100644
index f2623de..0000000
--- a/src/runtime/gc.c
+++ /dev/null
@@ -1,264 +0,0 @@
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <sys/mman.h>
-
-#define MINIMUM_THRESHOLD (1024 * 1024 * 8)
-#define MINIMUM_BLOCK_SIZE 4096
-
-typedef struct alloc_block {
-    uint64_t mark;
-    uint64_t size;
-    struct alloc_block* next;
-} alloc_block_t;
-
-typedef struct free_block {
-    uint64_t size;
-    struct free_block* next;
-} free_block_t;
-
-static alloc_block_t* alloc_list_head = NULL;
-static free_block_t* free_list_head = NULL;
-static void* stack_start = NULL;
-static int64_t free_list_size = 0;
-static int64_t mark_count = 0;
-
-/* Bytes allocated since last collect */
-static int64_t bytes_allocated = 0;
-/* Threshold for next collect */
-static int64_t trigger_threshold = MINIMUM_THRESHOLD;
-
-static void* sys_mmap(size_t size);
-static void* get_sp(void);
-static void gc_collect(void);
-static void gc_mark(void* ptr);
-static void gc_mark_stack(void);
-static void gc_sweep(void);
-static int64_t max(int64_t a, int64_t b);
-static void insert_into_free(free_block_t* block);
-static void merge(free_block_t* block);
-
-void gc_init(void) {
-    stack_start = get_sp();
-}
-
-/* Allocate memory with garbage collection */
-void* gc_alloc(int64_t size) {
-    size += sizeof(alloc_block_t);  // Adjust for metadata size
-
-    if (bytes_allocated > trigger_threshold) {
-        gc_collect();
-    }
-
-    bytes_allocated += size;
-
-    // Search free list for a suitable block
-    free_block_t* current = free_list_head;
-    free_block_t* prev = NULL;
-
-    while (current != NULL) {
-        if (current->size >= size) {
-            // Found a suitable block
-            break;
-        }
-        prev = current;
-        current = current->next;
-    }
-
-    if (current == NULL) {
-        // No suitable block found, allocate a new one
-        int64_t alloc_size = max(size, MINIMUM_BLOCK_SIZE);
-        void* memory = sys_mmap(alloc_size);
-
-        free_block_t* new_block = (free_block_t*)memory;
-        new_block->size = alloc_size - sizeof(free_block_t);
-        new_block->next = NULL;
-
-        insert_into_free(new_block);
-        current = new_block;
-
-        // Recalculate prev
-        if (current == free_list_head) {
-            prev = NULL;
-        } else {
-            prev = free_list_head;
-            while (prev->next != current) {
-                prev = prev->next;
-            }
-        }
-    }
-
-    // Use the block
-    alloc_block_t* result;
-
-    if (current->size > size) {
-        // Block is larger than needed, split it
-        result = (alloc_block_t*)((char*)current + current->size + sizeof(free_block_t) - size);
-        current->size -= size;
-    } else {
-        // Use the entire block
-        result = (alloc_block_t*)current;
-
-        // Remove block from free list
-        if (prev == NULL) {
-            free_list_head = current->next;
-        } else {
-            prev->next = current->next;
-        }
-
-        free_list_size--;
-    }
-
-    // Initialize metadata
-    result->mark = 0;
-    result->size = size - sizeof(alloc_block_t);
-    result->next = alloc_list_head;
-    alloc_list_head = result;
-
-    // Return pointer to usable memory
-    return (void*)(result + 1);
-}
-
-/* Run garbage collection */
-static void gc_collect(void) {
-    gc_mark_stack();
-    gc_sweep();
-    trigger_threshold = max(bytes_allocated * 2, MINIMUM_THRESHOLD);
-    bytes_allocated = 0;
-}
-
-static void gc_mark_stack(void) {
-    mark_count = 0;
-
-    void** current = get_sp();
-    void** end = (void**)stack_start;
-
-    while (current < end) {
-        gc_mark(*current);
-        current++;
-    }
-}
-
-/* Mark a single object and recursively mark its contents */
-static void gc_mark(void* ptr) {
-    if (ptr == NULL) {
-        return;
-    }
-
-    alloc_block_t* block = alloc_list_head;
-    while (block != NULL) {
-        void* block_data = (void*)(block + 1);
-        if (block_data == ptr) {
-            if (block->mark == 0) {
-                mark_count++;
-                block->mark = 1;
-
-                void** p = (void**)block_data;
-                void** end = (void**)((char*)block_data + block->size);
-                while (p < end) {
-                    gc_mark(*p);
-                    p++;
-                }
-            }
-            return;
-        }
-        block = block->next;
-    }
-}
-
-static void gc_sweep(void) {
-    alloc_block_t* current = alloc_list_head;
-    alloc_block_t* prev = NULL;
-
-    while (current != NULL) {
-        if (current->mark == 0) {
-            alloc_block_t* next = current->next;
-
-            if (prev == NULL) {
-                alloc_list_head = next;
-            } else {
-                prev->next = next;
-            }
-
-            bytes_allocated -= (current->size + sizeof(alloc_block_t));
-
-            free_block_t* free_block = (free_block_t*)current;
-            free_block->size = current->size + sizeof(alloc_block_t) - sizeof(free_block_t);
-            free_block->next = NULL;
-
-            insert_into_free(free_block);
-
-            current = next;
-        } else {
-            current->mark = 0;
-            prev = current;
-            current = current->next;
-        }
-    }
-}
-
-/* Insert a block into the free list, maintaining address order */
-static void insert_into_free(free_block_t* block) {
-    if (free_list_head == NULL || block < free_list_head) {
-        // Insert at head
-        block->next = free_list_head;
-        free_list_head = block;
-        free_list_size++;
-        merge(block);
-        return;
-    }
-
-    // Find insertion point
-    free_block_t* current = free_list_head;
-    while (current->next != NULL && current->next < block) {
-        current = current->next;
-    }
-
-    // Insert after current
-    block->next = current->next;
-    current->next = block;
-    free_list_size++;
-
-    // Try to merge adjacent blocks
-    merge(current);
-}
-
-static void merge(free_block_t* block) {
-    while (block->next != NULL) {
-        char* block_end = (char*)block + block->size + sizeof(free_block_t);
-        if (block_end == (char*)block->next) {
-            free_list_size--;
-            block->size += block->next->size + sizeof(free_block_t);
-            block->next = block->next->next;
-        } else {
-            break;
-        }
-    }
-}
-
-static void* sys_mmap(size_t size) {
-    void* result = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
-
-    if (result == MAP_FAILED) {
-        perror("[sys_mmap] mmap failed");
-        exit(1);
-    }
-
-    return result;
-}
-
-static int64_t max(int64_t a, int64_t b) {
-    if (a > b) {
-        return a;
-    } else {
-        return b;
-    }
-}
-
-void* get_sp(void) {
-    volatile unsigned long var = 0;
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wreturn-local-addr"
-    return (void*)((unsigned long)&var + 4);
-#pragma GCC diagnostic pop
-}
\ No newline at end of file