diff --git a/ccodegen.cpp b/ccodegen.cpp
index 6dc19d9..0108f75 100644
--- a/ccodegen.cpp
+++ b/ccodegen.cpp
@@ -28,6 +28,10 @@ gen_simple_decl_prefix(Ast_Resolved_Type *ast){
     case TYPE_Pointer:{gen_simple_decl_prefix(ast->base); gen("*");} break;
     case TYPE_Array: gen_simple_decl_prefix(ast->base); break;
     case TYPE_Lambda:break;
+    case TYPE_Struct: {
+      auto name = ast->sym->name;
+      gen("%s ", name.str);
+    }break;
     invalid_default_case;
   }
 }
@@ -43,6 +47,7 @@ gen_simple_decl_postfix(Ast_Resolved_Type *ast){
     case TYPE_Pointer: gen_simple_decl_postfix(ast->base); break;
     case TYPE_Array: gen("[%d]", (int)ast->arr.size); gen_simple_decl_postfix(ast->arr.base); break;
     case TYPE_Lambda:break;
+    case TYPE_Struct:break;
     invalid_default_case;
   }
 }
@@ -279,15 +284,20 @@ gen_ast(Ast *ast){
       }
       else if(sym->type == type_type){
         if(sym->type_val->kind == TYPE_Struct){
-          Ast_Struct *agg = (Ast_Struct *)node->value;
-          gen("struct %s{", node->name.str);
-          global_indent++;
-          For(agg->members){
-            genln("");
-            gen_ast(it[0]);
+          Ast_Struct *agg = const_get_struct(sym->type_val->sym->ast);
+          if(node->value->kind == AST_STRUCT){
+            gen("struct %s{", node->name.str);
+            global_indent++;
+            For(agg->members){
+              genln("");
+              gen_ast(it[0]);
+            }
+            global_indent--;
+            genln("};");
+          }
+          else{
+            // type alias
           }
-          global_indent--;
-          genln("};");
         }
         else{
           gen("// typedef ");
diff --git a/main.cpp b/main.cpp
index d4bd39c..6735718 100644
--- a/main.cpp
+++ b/main.cpp
@@ -48,8 +48,8 @@ int main(){
   test_intern_table();
   lex_test();
 
-  // String result = compile_file("globals.kl"_s);
-  String result = compile_file("structs.kl"_s);
+  String result = compile_file("globals.kl"_s);
+  // String result = compile_file("structs.kl"_s);
   // String result = compile_file("order_independent_globals.kl"_s);
   printf("%s", result.str);
 
diff --git a/new_ast.cpp b/new_ast.cpp
index 5489b16..ff49ba1 100644
--- a/new_ast.cpp
+++ b/new_ast.cpp
@@ -111,6 +111,7 @@ enum{
   AST_STMT = 2,
   AST_BINDING = 4,
   AST_AGGREGATE = 8,
+  AST_ATOM = 16,
 };
 
 struct Ast{
@@ -120,12 +121,6 @@ struct Ast{
   Ast_Kind kind;
   Ast *parent;
   Ast_Flag flags;
-  // @todo?
-  // bool is_atom: 1;
-  // bool is_stmt: 1;
-  // bool is_decl: 1;
-  // bool is_expr: 1;
-  // bool is_named: 1;
 };
 
 struct Ast_Resolved_Type;
@@ -252,21 +247,21 @@ struct Ast_Package:Ast{
 
 function Ast_Atom *
 ast_str(Token *pos, Intern_String string, Ast_Flag flags = 0){
-  AST_NEW(Atom, STR, pos,flags);
+  AST_NEW(Atom, STR, pos, AST_ATOM | flags);
   result->intern_val = string;
   return result;
 }
 
 function Ast_Atom *
 ast_ident(Token *pos, Intern_String string, Ast_Flag flags = 0){
-  AST_NEW(Atom, IDENT, pos,flags);
+  AST_NEW(Atom, IDENT, pos, AST_ATOM | flags);
   result->intern_val = string;
   return result;
 }
 
 function Ast_Atom *
 ast_int(Token *pos, S64 integer, Ast_Flag flags = 0){
-  AST_NEW(Atom, INT, pos,flags);
+  AST_NEW(Atom, INT, pos, AST_ATOM | flags);
   result->int_val = integer;
   return result;
 }
diff --git a/new_resolve.cpp b/new_resolve.cpp
index 999c6ab..1a56e25 100644
--- a/new_resolve.cpp
+++ b/new_resolve.cpp
@@ -153,6 +153,19 @@ sym_insert_builtins(){
 function Sym *resolve_name(Token *pos, Intern_String name);
 function Operand eval_expr(Ast_Expr *ast, Ast_Resolved_Type *compound_required_type = 0, Sym *lambda_to_complete = 0);
 
+enum{
+  AST_CANT_BE_NULL = 0,
+  AST_CAN_BE_NULL = 1
+};
+
+function Ast_Resolved_Type *
+eval_typespec(Ast_Expr *ast, B32 ast_can_be_null = AST_CANT_BE_NULL){
+  if(ast_can_be_null && ast == 0) return 0;
+  Operand resolved = eval_expr(ast);
+  if(resolved.type != type_type) parsing_error(ast->pos, "Expected [Type] got instead %s", resolved.type->kind);
+  return resolved.type_val;
+}
+
 function Ast_Resolved_Type *
 resolve_type_pair(Token *pos, Ast_Resolved_Type *a, Ast_Resolved_Type *b){
   Ast_Resolved_Type *result = 0;
@@ -227,18 +240,6 @@ eval_stmt(Ast *ast, Ast_Resolved_Type *ret){
   }
 }
 
-enum{
-  AST_CAN_BE_NULL = 1
-};
-
-function Ast_Resolved_Type *
-eval_typespec(Ast_Expr *ast, B32 ast_can_be_null){
-  if(ast_can_be_null && ast == 0) return 0;
-  Operand resolved = eval_expr(ast);
-  if(resolved.type != type_type) parsing_error(ast->pos, "Expected [Type] got instead %s", resolved.type->kind);
-  return resolved.type_val;
-}
-
 function Operand
 eval_expr(Ast_Expr *ast, Ast_Resolved_Type *expected_type, Sym *lambda_to_complete){
   switch(ast->kind){
@@ -266,33 +267,7 @@ eval_expr(Ast_Expr *ast, Ast_Resolved_Type *expected_type, Sym *lambda_to_comple
         if(!expected_type) parsing_error(node->pos, "Couldn't infer type of null");
         result.type = expected_type;
         result.is_const = true;
-        if(expected_type == type_int){
-          result.int_val = 0;
-          node->kind = AST_INT;
-          node->int_val = 0;
-        }
-        else if(expected_type->kind == TYPE_Pointer){
-          result.int_val = 0;
-          node->kind = AST_IDENT;
-          node->intern_val = pctx->intern("NULL_POINTER"_s);
-        }
-        else if(expected_type->kind == TYPE_Lambda){
-          result.int_val = 0;
-          node->kind = AST_IDENT;
-          node->intern_val = pctx->intern("NULL_LAMBDA"_s);
-        }
-        else if(expected_type == type_bool){
-          result.int_val = 0;
-          node->kind = AST_IDENT;
-          node->intern_val = pctx->intern("false"_s);
-        }
-        else if(expected_type == type_string){
-          result.intern_val = pctx->intern(""_s);
-          node->kind = AST_STR;
-          node->intern_val = result.intern_val;
-        }
       }
-
       else if(sym->kind == SYM_CONST || sym->kind == SYM_VAR){
         result.type     = sym->type;
         result.is_const = sym->kind == SYM_CONST ? true : false;
@@ -322,15 +297,14 @@ eval_expr(Ast_Expr *ast, Ast_Resolved_Type *expected_type, Sym *lambda_to_comple
       // @note: first resolve type of lambda
       Scratch scratch;
       Ast_Resolved_Type *lambda_type = 0;
-      Operand ret_op = eval_expr(node->ret);
+      Ast_Resolved_Type *ret_type = eval_typespec(node->ret);
       Array<Ast_Resolved_Type *> args = {scratch};
-      if(ret_op.type != type_type) parsing_error(node->pos, "Return type of [Lambda] should be a [Type] not %s", ret_op.type);
       For(node->args){
         Operand type = eval_expr(it[0]->typespec);
         if(type.type != type_type) parsing_error(it[0]->pos, "Required expression of kind [type]");
         args.add(type.type_val);
       }
-      lambda_type = type_lambda(ret_op.type_val, args);
+      lambda_type = type_lambda(ret_type, args);
       {
         assert(lambda_type);
         Value val; val.type_val = lambda_type;
@@ -355,7 +329,7 @@ eval_expr(Ast_Expr *ast, Ast_Resolved_Type *expected_type, Sym *lambda_to_comple
           sym_insert(arg_sym);
         }
         For(node->block->stmts){
-          eval_stmt(it[0], ret_op.type_val);
+          eval_stmt(it[0], ret_type);
         }
         scope_close(scope_index);
         result.type = lambda_type;
@@ -410,9 +384,7 @@ eval_expr(Ast_Expr *ast, Ast_Resolved_Type *expected_type, Sym *lambda_to_comple
 
     Ast_Begin(AST_CAST, Ast_Cast){
       Operand expr = eval_expr(node->expr);
-      Operand typespec = eval_expr(node->typespec);
-      if(typespec.type != type_type) parsing_error(node->pos, "Expected type in left of cast got instead %s", type_names[typespec.type->kind]);
-      Ast_Resolved_Type *type = typespec.type_val;
+      Ast_Resolved_Type *type = eval_typespec(node->typespec);
 
       if(type == expr.type) return expr;
 
@@ -484,7 +456,10 @@ eval_expr(Ast_Expr *ast, Ast_Resolved_Type *expected_type, Sym *lambda_to_comple
       Ast_End();
     }
 
+    // @todo: add const prepass? expecting only structs, exprs, lambdas
     Ast_Begin(AST_STRUCT, Ast_Struct){
+      assert(lambda_to_complete);
+
       Scratch scratch;
       Array<Ast_Resolved_Type_Field> members = {scratch};
       For(node->members){
@@ -499,7 +474,7 @@ eval_expr(Ast_Expr *ast, Ast_Resolved_Type *expected_type, Sym *lambda_to_comple
         sym_new_resolved(SYM_VAR, name, op.type, {}, it[0]);
         members.add({op.type, name});
       }
-      Ast_Resolved_Type *resolved = type_struct(members);
+      Ast_Resolved_Type *resolved = type_struct(lambda_to_complete, members);
       Operand result = {type_type, true}; result.type_val = resolved;
       return result;
 
@@ -517,10 +492,9 @@ eval_binding(Ast *ast, Sym *sym){
   switch(ast->kind){
 
     Ast_Begin(AST_VAR, Ast_Var){
-      Operand type = node->typespec ? eval_expr(node->typespec) : Operand{};
-      if(type.type && (type.type != type_type)) parsing_error(node->typespec->pos, "Expected [Type] got instead %s", type_names[type.type->kind]);
-      Operand expr = node->expr ? eval_expr(node->expr, type.type_val) : Operand{};
-      expr.type = resolve_type_pair(node->pos, type.type_val, expr.type);
+      Ast_Resolved_Type *type = eval_typespec(node->typespec, AST_CAN_BE_NULL);
+      Operand expr = node->expr ? eval_expr(node->expr, type) : Operand{};
+      expr.type = resolve_type_pair(node->pos, type, expr.type);
       return expr;
       Ast_End();
     }
@@ -537,18 +511,12 @@ eval_binding(Ast *ast, Sym *sym){
   }
 }
 
-function Ast_Lambda *
-ast_get_lambda(Ast *ast){
-  if(ast->kind == AST_CONST){
-    auto ast_const = (Ast_Const *)ast;
-    if(ast_const->value){
-      auto ast_expr = ast_const->value;
-      if(ast_expr->kind == AST_LAMBDA){
-        return (Ast_Lambda *)ast_expr;
-      }
-    }
-  }
-  return 0;
+function Ast_Struct *
+const_get_struct(Ast *ast){
+  assert(ast->kind == AST_CONST);
+  Ast_Const *constant = (Ast_Const *)ast;
+  assert(constant->value->kind == AST_STRUCT);
+  return (Ast_Struct *)constant->value;
 }
 
 function void
@@ -610,6 +578,13 @@ parse_file(){
     else invalid_codepath;
 
     Sym *sym = sym_new(kind, decl->name, decl);
+    // if(kind == SYM_CONST){
+    //   auto constant = (Ast_Const *)decl;
+    //   if(constant->value->kind == AST_STRUCT) {
+    //     sym->type = type_incomplete(sym);
+    //     sym->state = SYM_RESOLVED;
+    //   }
+    // }
     sym_insert(sym);
 
     decls.add(decl);
diff --git a/new_type.cpp b/new_type.cpp
index bebc8bd..32f2958 100644
--- a/new_type.cpp
+++ b/new_type.cpp
@@ -1,6 +1,7 @@
 enum Ast_Resolved_Type_Kind{
   TYPE_None,
   TYPE_Null,
+  TYPE_Incomplete,
   TYPE_Int,
   TYPE_Bool,
   TYPE_Unsigned,
@@ -18,6 +19,7 @@ enum Ast_Resolved_Type_Kind{
 const char *type_names[] = {
   "[Invalid Ast_Resolved_Type]",
   "[Null]",
+  "[Incomplete]",
   "[Int]",
   "[Bool]",
   "[Unsigned]",
@@ -42,6 +44,8 @@ struct Ast_Resolved_Type{
   Ast_Resolved_Type_Kind kind;
   SizeU size;
   SizeU align;
+
+  Sym *sym;
   union{
     Ast_Resolved_Type *base;
     struct{
@@ -145,9 +149,23 @@ type_lambda(Ast_Resolved_Type *ret, Array<Ast_Resolved_Type *> args){
 }
 
 function Ast_Resolved_Type *
-type_struct(Array<Ast_Resolved_Type_Field> fields){
+type_incomplete(Sym *sym){
+  Ast_Resolved_Type *result = type_new(pctx->perm, TYPE_Incomplete, 0, 0);
+  result->sym = sym;
+  return result;
+}
+
+function void
+type_complete_struct(Ast_Resolved_Type *type, Array<Ast_Resolved_Type_Field> fields){
+  type->agg.fields = fields.tight_copy(pctx->perm);
+  type->kind = TYPE_Struct;
+}
+
+function Ast_Resolved_Type *
+type_struct(Sym *sym, Array<Ast_Resolved_Type_Field> fields){
   Ast_Resolved_Type *result = type_new(pctx->perm, TYPE_Struct, 0, 0); // @todo: align,size
   result->agg.fields = fields.tight_copy(pctx->perm);
+  result->sym = sym;
   return result;
 }
 
diff --git a/structs.kl b/structs.kl
index 1d64196..e3ec23d 100644
--- a/structs.kl
+++ b/structs.kl
@@ -1,6 +1,22 @@
 
+arena_pointer: *Arena = null
 Arena :: struct
+//  next: *Arena
   data: *int
   len : int
   cap : int
 
+string16: Str16
+
+String16 :: struct
+  data: *void
+  len : int
+
+thing: Arena
+no_type := thing
+with_type: Arena = thing
+pointer := &with_type
+deref := *pointer
+
+
+Str16 :: String16
\ No newline at end of file