diff --git a/src/llvm/link/lld.c b/src/llvm/link/lld.c
index 62b5e65..7aa5be4 100644
--- a/src/llvm/link/lld.c
+++ b/src/llvm/link/lld.c
@@ -72,12 +72,6 @@ TargetLinkConfig* lld_create_link_config(const Target* target, const TargetConfi
 BackendError lld_link_target(TargetLinkConfig* config) {
     BackendError err = SUCCESS;
 
-    char* 
-
-    for (guint i = 0; i < config->object_file_names->len; i++) {
-        const char* path = g_array_index(config->object_file_names, const char*, i);
-    }
-
     return err;
 }
 
diff --git a/src/llvm/llvm-ir/expr.c b/src/llvm/llvm-ir/expr.c
index 6896ce1..771b471 100644
--- a/src/llvm/llvm-ir/expr.c
+++ b/src/llvm/llvm-ir/expr.c
@@ -248,7 +248,7 @@ BackendError impl_transmute(LLVMBackendCompileUnit *unit, LLVMLocalScope *scope,
     LLVMValueRef operand = NULL;
     LLVMTypeRef target_type = NULL;
     BackendError err = get_type_impl(unit, scope->func_scope->global_scope,
-                                     &transmute->targetType, &target_type);
+                                     transmute->targetType, &target_type);
     // if target type is valid
     if (err.kind == Success) {
         *llvm_result =
@@ -276,13 +276,13 @@ BackendError impl_typecast(LLVMBackendCompileUnit *unit, LLVMLocalScope *scope,
     LLVMValueRef operand = NULL;
     LLVMTypeRef target_type = NULL;
     BackendError err = get_type_impl(unit, scope->func_scope->global_scope,
-                                     &typecast->targetType, &target_type);
+                                     typecast->targetType, &target_type);
     // if target type is valid
     if (err.kind != Success) {
         return err;
     }
 
-    LLVMBool dst_signed = is_type_signed(&typecast->targetType);
+    LLVMBool dst_signed = is_type_signed(typecast->targetType);
     // TODO: derive source type sign
     const LLVMOpcode opcode =
             LLVMGetCastOpcode(operand, 0, target_type, dst_signed);
diff --git a/src/llvm/llvm-ir/func.c b/src/llvm/llvm-ir/func.c
index 107b697..5fa251e 100644
--- a/src/llvm/llvm-ir/func.c
+++ b/src/llvm/llvm-ir/func.c
@@ -6,6 +6,7 @@
 #include <llvm/llvm-ir/func.h>
 #include <llvm/parser.h>
 #include <llvm/llvm-ir/types.h>
+#include <llvm/llvm-ir/stmt.h>
 #include <set/types.h>
 #include <sys/log.h>
 
@@ -46,18 +47,18 @@ LLVMValueRef get_variable(const LLVMLocalScope* scope, const char* name) {
 }
 
 BackendError impl_param_type(LLVMBackendCompileUnit* unit,
-                             LLVMGlobalScope* scope, Paramer* param,
+                             LLVMGlobalScope* scope, Parameter* param,
                              LLVMTypeRef* llvm_type) {
     BackendError err = SUCCESS;
 
     Type* gemstone_type = NULL;
-    IO_Qualifier qualifier = In;
+    IO_Qualifier qualifier;
 
     if (param->kind == ParameterDeclarationKind) {
-        gemstone_type = &param->impl.declaration.type;
+        gemstone_type = param->impl.declaration.type;
         qualifier = param->impl.declaration.qualifier;
     } else {
-        gemstone_type = &param->impl.definiton.declaration.type;
+        gemstone_type = param->impl.definiton.declaration.type;
         qualifier = param->impl.definiton.declaration.qualifier;
     }
 
@@ -82,11 +83,11 @@ BackendError impl_func_decl(LLVMBackendCompileUnit* unit,
     DEBUG("implementing function declaration: %s()", name);
     BackendError err = SUCCESS;
 
-    Paramer* params = (Paramer*)fundef->parameter;
+    Parameter* params = (Parameter*)fundef->parameter;
     GArray* llvm_params = g_array_new(FALSE, FALSE, sizeof(LLVMTypeRef));
 
     for (size_t i = 0; i < fundef->parameter->len; i++) {
-        Paramer* param = &params[i];
+        Parameter* param = &params[i];
 
         LLVMTypeRef llvm_type = NULL;
         err = impl_param_type(unit, scope, param, &llvm_type);
@@ -138,12 +139,12 @@ BackendError impl_func(LLVMBackendCompileUnit* unit,
         // create value references for parameter
         const size_t params = fundef->parameter->len;
         for (size_t i = 0; i < params; i++) {
-            const Paramer* param = ((Paramer*)fundef->parameter) + i;
+            const Parameter* param = ((Parameter*)fundef->parameter) + i;
             g_hash_table_insert(func_scope->params, (gpointer)param->name,
                                 LLVMGetParam(llvm_func, i));
         }
 
-        // TODO: parse function body
+        err = impl_block(unit, builder, func_scope, fundef->body);
 
         LLVMDisposeBuilder(builder);
 
@@ -165,7 +166,7 @@ BackendError impl_functions(LLVMBackendCompileUnit* unit,
 
     BackendError err = SUCCESS;
 
-    size_t variable_count = 0;
+    size_t function_count = 0;
     while (g_hash_table_iter_next(&iterator, &key, &val) != FALSE) {
         err =
             impl_func(unit, scope, (FunctionDefinition*)val, (const char*)key);
@@ -174,8 +175,9 @@ BackendError impl_functions(LLVMBackendCompileUnit* unit,
             break;
         }
 
-        variable_count++;
+        function_count++;
     }
+    INFO("implemented %ld functions", function_count);
 
     return err;
 }
diff --git a/src/llvm/llvm-ir/stmt.c b/src/llvm/llvm-ir/stmt.c
index 8692168..189636b 100644
--- a/src/llvm/llvm-ir/stmt.c
+++ b/src/llvm/llvm-ir/stmt.c
@@ -8,22 +8,31 @@
 #include <llvm/llvm-ir/stmt.h>
 #include <llvm/llvm-ir/expr.h>
 #include <llvm/llvm-ir/func.h>
+#include <llvm/llvm-ir/types.h>
 
-BackendError impl_assign_stmt([[maybe_unused]] LLVMBackendCompileUnit *unit,
-                              const LLVMBuilderRef builder, const LLVMLocalScope *scope,
-                              const Assignment *assignment) {
+BackendError impl_assign_stmt(
+        LLVMBackendCompileUnit *unit,
+        LLVMBuilderRef
+        builder,
+        LLVMLocalScope *scope,
+        const Assignment *assignment
+) {
     BackendError err = SUCCESS;
-    DEBUG("implementing assignment for variabel: %s", assignment->variable->name);
+    DEBUG("implementing assignment for variable: %s", assignment->variable->name);
 
-    // TODO: resolve expression to LLVMValueRef
-    const LLVMValueRef llvm_value = NULL;
+    LLVMValueRef llvm_value = NULL;
+    err = impl_expr(unit, scope, builder, assignment->value, &llvm_value);
+    if (err.kind != Success) {
+        return err;
+    }
 
     switch (assignment->variable->kind) {
         case VariableKindDeclaration:
         case VariableKindDefinition:
-            const LLVMValueRef llvm_ptr =
+            LLVMValueRef llvm_ptr =
                     get_variable(scope, assignment->variable->name);
-            LLVMBuildStore(builder, llvm_value, llvm_ptr);
+            LLVMBuildStore(builder, llvm_value, llvm_ptr
+            );
             break;
         case VariableKindBoxMember:
             // TODO: resolve LLVMValueRef from BoxAccess
@@ -45,10 +54,8 @@ BackendError impl_basic_block(LLVMBackendCompileUnit *unit,
     LLVMPositionBuilderAtEnd(builder, *llvm_block);
 
     for (size_t i = 0; i < block->statemnts->len; i++) {
-        [[maybe_unused]]
         Statement *stmt = ((Statement *) block->statemnts->data) + i;
-
-        // TODO: implement statement
+        impl_stmt(unit, builder, scope, stmt);
     }
 
     delete_local_scope(block_scope);
@@ -67,7 +74,7 @@ BackendError impl_while(LLVMBackendCompileUnit *unit,
     LLVMPositionBuilderAtEnd(builder, while_cond_block);
     // Resolve condition in block to a variable
     LLVMValueRef cond_result = NULL;
-    impl_expr(unit, scope, builder, (Expression*) &while_stmt->conditon, &cond_result);
+    impl_expr(unit, scope, builder, (Expression *) &while_stmt->conditon, &cond_result);
 
     // build body of loop
     LLVMBasicBlockRef while_body_block = NULL;
@@ -88,6 +95,19 @@ BackendError impl_while(LLVMBackendCompileUnit *unit,
     return err;
 }
 
+gboolean is_parameter_out(Parameter *param) {
+    gboolean is_out = FALSE;
+
+    if (param->kind == ParameterDeclarationKind) {
+        is_out = param->impl.declaration.qualifier == Out || param->impl.declaration.qualifier == InOut;
+    } else {
+        is_out = param->impl.definiton.declaration.qualifier == Out ||
+                 param->impl.definiton.declaration.qualifier == InOut;
+    }
+
+    return is_out;
+}
+
 BackendError impl_func_call(LLVMBackendCompileUnit *unit,
                             LLVMBuilderRef builder, LLVMLocalScope *scope,
                             const FunctionCall *call) {
@@ -104,9 +124,12 @@ BackendError impl_func_call(LLVMBackendCompileUnit *unit,
             break;
         }
 
-        [[maybe_unused]]
-        Paramer* parameter = (Paramer*) call->function->parameter->data + i;
-        // TODO: create a pointer to LLVMValueRef in case parameter is `out`
+        Parameter *parameter = g_array_index(call->function->parameter, Parameter*, i);
+
+        if (is_parameter_out(parameter)) {
+            LLVMValueRef zero = LLVMConstInt(LLVMInt32TypeInContext(unit->context), 0, 0);
+            llvm_arg = LLVMBuildGEP2(builder, LLVMTypeOf(llvm_arg), llvm_arg, &zero, 1, "");
+        }
 
         g_array_append_vals(arguments, &llvm_arg, 1);
     }
@@ -157,7 +180,8 @@ BackendError impl_branch(LLVMBackendCompileUnit *unit,
         LLVMBasicBlockRef body_block = NULL;
         LLVMValueRef cond_value = NULL;
 
-        err = impl_cond_block(unit, builder, scope, (Expression*) &branch->ifBranch.conditon, &branch->ifBranch.block, &cond_block,
+        err = impl_cond_block(unit, builder, scope, (Expression *) &branch->ifBranch.conditon, &branch->ifBranch.block,
+                              &cond_block,
                               &body_block, &cond_value);
 
         g_array_append_val(cond_blocks, cond_block);
@@ -173,7 +197,7 @@ BackendError impl_branch(LLVMBackendCompileUnit *unit,
 
         ElseIf *elseIf = ((ElseIf *) branch->elseIfBranches->data) + i;
 
-        err = impl_cond_block(unit, builder, scope, &elseIf->conditon, &elseIf->block, &cond_block,
+        err = impl_cond_block(unit, builder, scope, elseIf->conditon, &elseIf->block, &cond_block,
                               &body_block, &cond_value);
 
         g_array_append_val(cond_blocks, cond_block);
@@ -198,10 +222,10 @@ BackendError impl_branch(LLVMBackendCompileUnit *unit,
     }
 
     for (size_t i = 0; i < cond_blocks->len - 1; i++) {
-        LLVMBasicBlockRef next_block = ((LLVMBasicBlockRef*) cond_blocks->data)[i + 1];
-        LLVMBasicBlockRef cond_block = ((LLVMBasicBlockRef*) cond_blocks->data)[i];
-        LLVMBasicBlockRef body_block = ((LLVMBasicBlockRef*) body_blocks->data)[i];
-        LLVMValueRef cond_value = ((LLVMValueRef*) cond_values->data)[i];
+        LLVMBasicBlockRef next_block = ((LLVMBasicBlockRef *) cond_blocks->data)[i + 1];
+        LLVMBasicBlockRef cond_block = ((LLVMBasicBlockRef *) cond_blocks->data)[i];
+        LLVMBasicBlockRef body_block = ((LLVMBasicBlockRef *) body_blocks->data)[i];
+        LLVMValueRef cond_value = ((LLVMValueRef *) cond_values->data)[i];
 
         LLVMPositionBuilderAtEnd(builder, cond_block);
         LLVMBuildCondBr(builder, cond_value, body_block, next_block);
@@ -217,7 +241,128 @@ BackendError impl_branch(LLVMBackendCompileUnit *unit,
     return err;
 }
 
-BackendError impl_stmt([[maybe_unused]] LLVMBackendCompileUnit *unit, [[maybe_unused]] Statement *stmt) {
-    // TODO: implement
-    return SUCCESS;
+BackendError impl_decl(LLVMBackendCompileUnit *unit,
+                       LLVMBuilderRef builder,
+                       LLVMLocalScope *scope,
+                       VariableDeclaration *decl,
+                       const char *name) {
+    DEBUG("implementing local declaration: %s", name);
+    BackendError err = SUCCESS;
+    LLVMTypeRef llvm_type = NULL;
+    err = get_type_impl(unit, scope->func_scope->global_scope, decl->type, &llvm_type);
+
+    if (err.kind != Success) {
+        return err;
+    }
+
+    DEBUG("creating local variable...");
+    LLVMValueRef local = LLVMBuildAlloca(builder, llvm_type, name);
+
+    LLVMValueRef initial_value = NULL;
+    err = get_type_default_value(unit, scope->func_scope->global_scope, decl->type, &initial_value);
+
+    if (err.kind == Success) {
+        DEBUG("setting default value...");
+        LLVMBuildStore(builder, initial_value, local);
+        g_hash_table_insert(scope->vars, (gpointer) name, local);
+    } else {
+        ERROR("unable to initialize local variable: %s", err.impl.message);
+    }
+
+    return err;
+}
+
+BackendError impl_def(LLVMBackendCompileUnit *unit,
+                      LLVMBuilderRef builder,
+                      LLVMLocalScope *scope,
+                      VariableDefiniton *def,
+                      const char *name) {
+    DEBUG("implementing local definition: %s", name);
+    BackendError err = SUCCESS;
+    LLVMTypeRef llvm_type = NULL;
+    err = get_type_impl(unit, scope->func_scope->global_scope, def->declaration.type, &llvm_type);
+
+    if (err.kind != Success) {
+        return err;
+    }
+
+    LLVMValueRef initial_value = NULL;
+    err = impl_expr(unit, scope, builder, def->initializer, &initial_value);
+    if (err.kind != Success) {
+        return err;
+    }
+
+    DEBUG("creating local variable...");
+    LLVMValueRef local = LLVMBuildAlloca(builder, llvm_type, name);
+
+    DEBUG("setting default value");
+    LLVMBuildStore(builder, initial_value, local);
+    g_hash_table_insert(scope->vars, (gpointer) name, local);
+    return err;
+}
+
+BackendError impl_var(LLVMBackendCompileUnit *unit,
+                      LLVMBuilderRef builder,
+                      LLVMLocalScope *scope,
+                      Variable *var) {
+    BackendError err;
+
+    switch (var->kind) {
+        VariableKindDeclaration:
+            err = impl_decl(unit, builder, scope, &var->impl.declaration, var->name);
+            break;
+        VariableKindDefinition:
+            err = impl_def(unit, builder, scope, &var->impl.definiton, var->name);
+            break;
+        default:
+            err = new_backend_impl_error(Implementation, NULL, "Unexpected variable kind in statement");
+            break;
+    }
+
+    return err;
+}
+
+BackendError impl_stmt(LLVMBackendCompileUnit *unit, LLVMBuilderRef builder, LLVMLocalScope *scope, Statement *stmt) {
+    BackendError err;
+
+    switch (stmt->kind) {
+        StatementKindAssignment:
+            err = impl_assign_stmt(unit, builder, scope, &stmt->impl.assignment);
+            break;
+        StatementKindBranch:
+            err = impl_branch(unit, builder, scope, &stmt->impl.branch);
+            break;
+        StatementKindDeclaration:
+        StatementKindDefinition:
+            err = impl_var(unit, builder, scope, stmt->impl.variable);
+            break;
+        StatementKindWhile:
+            err = impl_while(unit, builder, scope, &stmt->impl.whileLoop);
+            break;
+        StatementKindFunctionCall:
+            err = impl_func_call(unit, builder, scope, &stmt->impl.call);
+            break;
+        default:
+            err = new_backend_impl_error(Implementation, NULL, "Unexpected statement kind");
+    }
+
+    return err;
+}
+
+BackendError impl_block(LLVMBackendCompileUnit *unit,
+                        LLVMBuilderRef builder, LLVMFuncScope *scope,
+                        const Block *block) {
+    BackendError err = SUCCESS;
+
+    LLVMLocalScope *function_entry_scope = malloc(sizeof(LLVMLocalScope));
+    function_entry_scope->func_scope = scope;
+    function_entry_scope->vars = g_hash_table_new(g_str_hash, g_str_equal);
+    function_entry_scope->parent_scope = NULL;
+
+    LLVMBasicBlockRef llvm_block = NULL;
+    err = impl_basic_block(unit, builder, function_entry_scope, block, &llvm_block);
+
+    delete_local_scope(function_entry_scope);
+
+    return err;
 }
diff --git a/src/llvm/llvm-ir/stmt.h b/src/llvm/llvm-ir/stmt.h
index bde984d..a20c27c 100644
--- a/src/llvm/llvm-ir/stmt.h
+++ b/src/llvm/llvm-ir/stmt.h
@@ -5,5 +5,12 @@
 #ifndef LLVM_BACKEND_STMT_H
 #define LLVM_BACKEND_STMT_H
 
+#include <llvm/llvm-ir/func.h>
+
+BackendError impl_block(LLVMBackendCompileUnit *unit,
+                              LLVMBuilderRef builder, LLVMFuncScope *scope,
+                              const Block *block);
+
+BackendError impl_stmt(LLVMBackendCompileUnit *unit, LLVMBuilderRef builder, LLVMLocalScope *scope, Statement *stmt);
 
 #endif // LLVM_BACKEND_STMT_H
diff --git a/src/llvm/llvm-ir/types.c b/src/llvm/llvm-ir/types.c
index 3e4892d..9b241c4 100644
--- a/src/llvm/llvm-ir/types.c
+++ b/src/llvm/llvm-ir/types.c
@@ -41,19 +41,19 @@ BackendError get_const_type_value(LLVMBackendCompileUnit* unit,
         Implementation, gemstone_value->nodePtr, "No default value for type");
 
     LLVMTypeRef llvm_type = NULL;
-    err = get_type_impl(unit, scope, &gemstone_value->type, &llvm_type);
+    err = get_type_impl(unit, scope, gemstone_value->type, &llvm_type);
     if (err.kind != Success) {
         return err;
     }
 
-    switch (gemstone_value->type.kind) {
+    switch (gemstone_value->type->kind) {
         case TypeKindPrimitive:
-            err = get_const_primitive_value(gemstone_value->type.impl.primitive,
+            err = get_const_primitive_value(gemstone_value->type->impl.primitive,
                                             llvm_type, gemstone_value->value,
                                             llvm_value);
             break;
         case TypeKindComposite:
-            err = get_const_composite_value(gemstone_value->type.impl.composite,
+            err = get_const_composite_value(gemstone_value->type->impl.composite,
                                             llvm_type, gemstone_value->value,
                                             llvm_value);
             break;
@@ -68,7 +68,7 @@ BackendError get_const_type_value(LLVMBackendCompileUnit* unit,
                                        "boxes cannot be constant value");
             break;
         default:
-            PANIC("invalid value kind: %ld", gemstone_value->type.kind);
+            PANIC("invalid value kind: %ld", gemstone_value->type->kind);
     }
 
     return err;
diff --git a/src/llvm/llvm-ir/variables.c b/src/llvm/llvm-ir/variables.c
index 595dd35..05465d7 100644
--- a/src/llvm/llvm-ir/variables.c
+++ b/src/llvm/llvm-ir/variables.c
@@ -14,7 +14,7 @@ BackendError impl_global_declaration(LLVMBackendCompileUnit* unit,
     DEBUG("implementing global declaration: %s", name);
     BackendError err = SUCCESS;
     LLVMTypeRef llvm_type = NULL;
-    err = get_type_impl(unit, scope, &decl->type, &llvm_type);
+    err = get_type_impl(unit, scope, decl->type, &llvm_type);
 
     if (err.kind != Success) {
         return err;
@@ -24,7 +24,7 @@ BackendError impl_global_declaration(LLVMBackendCompileUnit* unit,
     LLVMValueRef global = LLVMAddGlobal(unit->module, llvm_type, name);
 
     LLVMValueRef initial_value = NULL;
-    err = get_type_default_value(unit, scope, &decl->type, &initial_value);
+    err = get_type_default_value(unit, scope, decl->type, &initial_value);
 
     if (err.kind == Success) {
         DEBUG("setting default value...");
@@ -43,7 +43,7 @@ BackendError impl_global_definiton(LLVMBackendCompileUnit* unit,
     DEBUG("implementing global definition: %s", name);
     BackendError err = SUCCESS;
     LLVMTypeRef llvm_type = NULL;
-    err = get_type_impl(unit, scope, &def->declaration.type, &llvm_type);
+    err = get_type_impl(unit, scope, def->declaration.type, &llvm_type);
 
     if (err.kind != Success) {
         return err;
@@ -54,7 +54,7 @@ BackendError impl_global_definiton(LLVMBackendCompileUnit* unit,
 
     // FIXME: resolve initializer expression!
     LLVMValueRef initial_value = NULL;
-    err = get_type_default_value(unit, scope, &def->declaration.type,
+    err = get_type_default_value(unit, scope, def->declaration.type,
                                  &initial_value);
 
     if (err.kind == Success) {
@@ -87,7 +87,6 @@ BackendError impl_global_variable(LLVMBackendCompileUnit* unit,
             break;
         default:
             PANIC("invalid variable kind: %ld", gemstone_var->kind);
-            break;
     }
 
     return err;
diff --git a/src/llvm/parser.c b/src/llvm/parser.c
index 05181d9..6cc1d21 100644
--- a/src/llvm/parser.c
+++ b/src/llvm/parser.c
@@ -243,7 +243,7 @@ BackendError parse_module(const Module* module, const TargetConfig* config) {
 
         export_module(unit, &target, config);
 
-        TargetLinkConfig* link_config = lld_create_link_config(&target, target, module);
+        TargetLinkConfig* link_config = lld_create_link_config(&target, config, module);
 
         lld_link_target(link_config);
 
diff --git a/src/set/types.h b/src/set/types.h
index 52744a1..b4744c9 100644
--- a/src/set/types.h
+++ b/src/set/types.h
@@ -5,39 +5,42 @@
 #include <glib.h>
 #include <ast/ast.h>
 
+// with of primitive types (int/float) in bytes
+#define BASE_BYTES 4
+
 /**
  * @brief Primitive types form the basis of all other types.
- * 
+ *
  */
 typedef enum PrimitiveType_t {
     // 4 byte signed integer in two's complement
-    Int,
+    Int =0,
     // 4 byte IEEE-754 single precision
-    Float
+    Float =1
 } PrimitiveType;
 
 /**
  * @brief Represents the sign of a composite type.
- * 
+ *
  */
 typedef enum Sign_t {
-    // type has a sign bit
-    Signed,
     // type has no sign bit
-    Unsigned
+    Unsigned = 0,
+    // type has a sign bit
+    Signed = 1
 } Sign;
 
 /**
  * @brief Represents the scale of composite type which is multiplied
  *        with the base size in order to retrieve the the composites size.
  * @attention Valid value are: { 1/8, 1/4, 1/2, 1, 2, 4, 8 }
- * 
+ *
  */
 typedef double Scale;
 
 /**
- * @brief A composite type is an extended definiton of a primitive type.
- * 
+ * @brief A composite type is an extended definition of a primitive type.
+ *
  */
 typedef struct CompositeType_t {
     // sign of composite
@@ -49,7 +52,7 @@ typedef struct CompositeType_t {
 
 /**
  * @brief Specifies the specific type of the generic type struct.
- * 
+ *
  */
 typedef enum TypeKind_t {
     TypeKindPrimitive,
@@ -63,27 +66,32 @@ typedef struct Type_t Type;
 /**
  * @brief Reference points to a type.
  * @attention Can be nested. A reference can point to another reference: REF -> REF -> REF -> Primitive
- * 
+ *
  */
 typedef Type* ReferenceType;
 
 typedef struct BoxType_t BoxType;
 
+typedef struct Block_t Block;
+
+typedef struct Expression_t Expression;
+
 typedef struct BoxMember_t {
     const char* name;
     Type* type;
     BoxType* box;
+    Expression* initalizer;
     AST_NODE_PTR nodePtr;
 } BoxMember;
 
 /**
- * @brief Essentially a glorified struct
- * 
+ * @brief Essentially a g   lorified struct
+ *
  */
 typedef struct BoxType_t {
     // hashtable of members.
-    // Associates the memebers name (const char*) with its type (BoxMember) 
-    GHashTable* member;
+    // Associates the memebers name (const char*) with its type (BoxMember)
+    GHashTable* member; //BoxMember Pointer
     AST_NODE_PTR nodePtr;
 } BoxType;
 
@@ -93,6 +101,8 @@ typedef struct BoxAccess_t {
     // list of recursive box accesses
     // contains a list of BoxMembers (each specifying their own type, name and box type)
     GArray* member;
+    // box variable to access
+    Variable* variable;
     AST_NODE_PTR nodePtr;
 } BoxAccess;
 
@@ -112,19 +122,19 @@ typedef struct Type_t {
 
 typedef struct Typedefine_t {
     const char* name;
-    Type type;
+    Type *type;
     AST_NODE_PTR nodePtr;
 } Typedefine;
 
 
 
 /**
- * @brief Reprents the value of type. Can be used to definitons, initialization and for expressions contants.
- * 
+ * @brief Reprents the value of type. Can be used to definitions, initialization and for expressions contants.
+ *
  */
 typedef struct TypeValue_t {
     // the type
-    Type type;
+    Type *type;
     // UTF-8 representation of the type's value
     const char* value;
     AST_NODE_PTR nodePtr;
@@ -136,7 +146,7 @@ typedef struct TypeValue_t {
 
 /**
  * @brief Specifies a parameters I/O properties
- * 
+ *
  */
 typedef enum IO_Qualifier_t {
     // Can be read from but not written to.
@@ -152,23 +162,23 @@ typedef enum IO_Qualifier_t {
 
 /**
  * @brief A functions parameter declaration.
- * 
+ *
  */
 typedef struct ParameterDeclaration_t {
-    Type type;
+    Type *type;
     IO_Qualifier qualifier;
     AST_NODE_PTR nodePtr;
 } ParameterDeclaration;
 
 /**
  * @brief A functions parameter.
- * 
+ *
  */
 typedef struct ParameterDefinition_t {
     ParameterDeclaration declaration;
     // value to initalize the declaration with
     // NOTE: type of initializer and declaration MUST be equal
-    TypeValue initializer;
+    Expression *initializer;
     AST_NODE_PTR nodePtr;
 } ParameterDefinition;
 
@@ -178,26 +188,54 @@ typedef enum ParameterKind_t {
 } ParameterKind;
 
 /**
- * @brief A parameter can either be a declaration or a definiton
- * 
+ * @brief A parameter can either be a declaration or a definition
+ *
  */
 typedef struct Parameter_t {
     const char* name;
+
     ParameterKind kind;
     union ParameterImplementation {
         ParameterDeclaration declaration;
         ParameterDefinition definiton;
     } impl;
     AST_NODE_PTR nodePtr;
-} Paramer; 
+} Parameter;    // fix typo
+
+typedef enum FunctionKind_t {
+    FunctionDeclarationKind,
+    FunctionDefinitionKind
+} FunctionKind;
 
 typedef struct FunctionDefinition_t {
     // hashtable of parameters
     // associates a parameters name (const char*) with its parameter declaration (ParameterDeclaration)
-    GArray* parameter;
+    GArray* parameter; // Parameter
     AST_NODE_PTR nodePtr;
+    // body of function
+    Block *body;
+    // name of function
+    const char* name;
 } FunctionDefinition;
 
+typedef struct FunctionDeclaration_t {
+    // hashtable of parameters
+    // associates a parameters name (const char*) with its parameter declaration (ParameterDeclaration)
+    GArray* parameter; // Parameter
+    AST_NODE_PTR nodePtr;
+    const char* name;
+} FunctionDeclaration;
+
+typedef struct Function_t {
+    FunctionKind kind;
+    union FunctionImplementation {
+        FunctionDefinition definition;
+        FunctionDeclaration declaration;
+    } impl;
+    AST_NODE_PTR nodePtr;
+    const char * name;
+} Function;
+
 // .------------------------------------------------.
 // |                 Variables                      |
 // '------------------------------------------------'
@@ -210,19 +248,19 @@ typedef enum StorageQualifier_t {
 
 typedef struct VariableDeclaration_t {
     StorageQualifier qualifier;
-    Type type;
+    Type *type;
     AST_NODE_PTR nodePtr;
 } VariableDeclaration;
 
 /**
- * @brief Definiton of a variable
- * 
+ * @brief Definition of a variable
+ *
  * @attention NOTE: The types of the initializer and the declaration must be equal
- * 
+ *
  */
 typedef struct VariableDefiniton_t {
     VariableDeclaration declaration;
-    TypeValue initializer;
+    Expression *initializer;
     AST_NODE_PTR nodePtr;
 } VariableDefiniton;
 
@@ -238,7 +276,7 @@ typedef struct Variable_t {
     union VariableImplementation {
         VariableDeclaration declaration;
         VariableDefiniton definiton;
-        BoxMember member;
+        BoxAccess member;
     } impl;
     AST_NODE_PTR nodePtr;
 } Variable;
@@ -249,15 +287,16 @@ typedef struct Variable_t {
 
 /**
  * @brief Perform a type cast, converting a value to different type whilest preserving as much of the original
- *        values information. 
+ *        values information.
  *
  * @attention NOTE: Must check wether the given value's type can be parsed into
  *       the target type without loss.
- *       Lossy mean possibly loosing information such when casting a float into an int (no fraction anymore). 
+ *       Lossy mean possibly loosing information such when casting a float into an int (no fraction anymore).
  *
  */
 typedef struct TypeCast_t {
-    Type targetType;
+    Type *targetType;
+    Expression* operand;
     AST_NODE_PTR nodePtr;
 } TypeCast;
 
@@ -266,10 +305,11 @@ typedef struct TypeCast_t {
  *
  * @attention NOTE: The given value's type must have the size in bytes as the target type.
  *                  Transmuting a short int into a float should yield an error.
- * 
+ *
  */
 typedef struct Transmute_t {
-    Type targetType;
+    Type *targetType;
+    Expression* operand;
     AST_NODE_PTR nodePtr;
 } Transmute;
 
@@ -279,13 +319,14 @@ typedef struct Transmute_t {
 
 /**
  * @brief Represents the arithmetic operator.
- * 
+ *
  */
 typedef enum ArithmeticOperator_t {
     Add,
     Sub,
     Mul,
-    Div
+    Div,
+    Negate
 } ArithmeticOperator;
 
 // .------------------------------------------------.
@@ -294,7 +335,7 @@ typedef enum ArithmeticOperator_t {
 
 /**
  * @brief Represents the relational operator.
- * 
+ *
  */
 typedef enum RelationalOperator_t {
     Equal,
@@ -358,6 +399,7 @@ typedef struct Operation_t {
         LogicalOperator logical;
         BitwiseOperator bitwise;
     } impl;
+    GArray* operands; //Expression*
     AST_NODE_PTR nodePtr;
 } Operation;
 
@@ -369,17 +411,20 @@ typedef enum ExpressionKind_t {
     ExpressionKindOperation,
     ExpressionKindTypeCast,
     ExpressionKindTransmute,
-    ExpressionKindConstant
+    ExpressionKindConstant,
+    ExpressionKindVariable
 } ExpressionKind;
 
 typedef struct Expression_t {
     ExpressionKind kind;
+    // type of resulting data
+    Type* result;
     union ExpressionImplementation_t {
         Operation operation;
         TypeCast typecast;
         Transmute transmute;
         TypeValue constant;
-        Variable variable;
+        Variable* variable;
     } impl;
     AST_NODE_PTR nodePtr;
 } Expression;
@@ -409,7 +454,7 @@ typedef struct FunctionBoxCall_t {
 
 typedef struct Block_t {
     // array of statements
-    GArray* statemnts;
+    GArray* statemnts; // array of type(Statement)
     AST_NODE_PTR nodePtr;
 } Block;
 
@@ -418,7 +463,7 @@ typedef struct Block_t {
 // '------------------------------------------------'
 
 typedef struct While_t {
-    Expression conditon;
+    Expression *conditon;
     Block block;
     AST_NODE_PTR nodePtr;
 } While;
@@ -428,13 +473,13 @@ typedef struct While_t {
 // '------------------------------------------------'
 
 typedef struct If_t {
-    Expression conditon;
+    Expression *conditon;
     Block block;
     AST_NODE_PTR nodePtr;
 } If;
 
 typedef struct ElseIf_t {
-    Expression conditon;
+    Expression *conditon;
     Block block;
     AST_NODE_PTR nodePtr;
 } ElseIf;
@@ -458,7 +503,7 @@ typedef struct Branch_t {
 
 typedef struct Assignment_t {
     Variable* variable;
-    Expression value;
+    Expression* value;
     AST_NODE_PTR nodePtr;
 } Assignment;
 
@@ -467,16 +512,20 @@ typedef enum StatementKind_t {
     StatementKindFunctionBoxCall,
     StatementKindWhile,
     StatementKindBranch,
-    StatementKindAssignment
+    StatementKindAssignment,
+    StatementKindDeclaration,
+    StatementKindDefinition
 } StatementKind;
 
 typedef struct Statement_t {
+    StatementKind kind;
     union StatementImplementation {
         FunctionCall call;
         FunctionBoxCall boxCall;
         While whileLoop;
         Branch branch;
         Assignment assignment;
+        Variable *variable;
     } impl;
     AST_NODE_PTR nodePtr;
 } Statement;
@@ -486,8 +535,8 @@ typedef struct Statement_t {
 // '------------------------------------------------'
 
 typedef struct Module_t {
-    GHashTable* boxes;
-    GHashTable* types;
+    GHashTable* boxes; //BoxType
+    GHashTable* types; //
     GHashTable* functions;
     GHashTable* variables;
     // to be resolved after the module has been parsed completely