diff --git a/bin/pre.slime b/bin/pre.slime
index 20f9267..76da091 100644
--- a/bin/pre.slime
+++ b/bin/pre.slime
@@ -85,9 +85,6 @@ condition is false."
            ,(rec (rest clauses))))))
   (rec clauses))
 
-(define-syntax (define-special name-and-args . body)
-  `(define ,(first name-and-args) (special-lambda ,(rest name-and-args) @body)))
-
 (define-syntax (construct-list . body)
   :doc "
 {{{example_start}}}
@@ -471,7 +468,6 @@ added to a list, which in the end is returned."
 ;;               (vector-ref v2 0))))
 
 
-
 ;; (unless (bound? generic-+-map)
 ;;   (set! generic-+-map (create-hash-map)))
 ;; (hm/set! generic-+-map '(:vector :vector) (lambda (v1 v2)
diff --git a/bin/pre.slime.expanded b/bin/pre.slime.expanded
index 67a5f2d..2cb2607 100644
--- a/bin/pre.slime.expanded
+++ b/bin/pre.slime.expanded
@@ -18,8 +18,6 @@
 
 (define-syntax (case var . clauses) (define (rec clauses) (if (= nil clauses) nil (if (= (first (first clauses)) 'else) (begin (if (not (= (rest clauses) ())) (error :syntax-error "There are additional clauses after the else clause!") (pair 'begin (rest (first clauses))))) `(if (member? ,var ',(first (first clauses))) (begin (unquote-splicing (rest (first clauses)))) ,(rec (rest clauses)))))) (rec clauses))
 
-(define-syntax (define-special name-and-args . body) `(define ,(first name-and-args) (special-lambda ,(rest name-and-args) (unquote-splicing body))))
-
 (define-syntax (construct-list . body) :doc "\n{{{example_start}}}\n(construct-list\n  i <- '(1 2 3 4 5)\n  yield (* i i))\n{{{example_end}}}\n\n(construct-list\n  i <- '(1 2 3 4)\n  j <- '(A B)\n  yield (pair i j))\n\n(construct-list\n  i <- '(1 2 3 4 5 6 7 8)\n  if (= 0 (% i 2))\n  yield i)\n" (define (append-map f ll) (unless (= ll ()) (define val (f (first ll))) (if (= (first val) ()) (append-map f (rest ll)) (extend val (append-map f (rest ll)))))) (define (rec body) (cond ((= () body) ()) ((= () (rest body)) (first body)) ((= (first (rest body)) '<-) `(,append-map (lambda (,(first body)) (list ,(rec (rest (rest (rest body)))))) ,(first (rest (rest body))))) ((= (first body) 'if) `(when ,(first (rest body)) ,(rec (rest (rest body))))) ((= (first (rest body)) 'yield) (first (rest body))) (else (error :syntax-error "Not a do-able expression")))) (rec body))
 
 (define-syntax (define-typed args . body) (define (get-arg-names args) (when args (pair (first args) (get-arg-names (rest (rest args)))))) (let ((name (first args)) (lambda-list (rest args)) (arg-names (get-arg-names (rest args)))) `(define (,name (unquote-splicing arg-names)) (assert-types= (unquote-splicing lambda-list)) (unquote-splicing body))))
diff --git a/build.sh b/build.sh
old mode 100644
new mode 100755
index 42362b2..a0308c9
--- a/build.sh
+++ b/build.sh
@@ -5,6 +5,7 @@ pushd $SCRIPTPATH > /dev/null
 #  _DEBUG
 # time g++ -fpermissive src/main.cpp -g -o ./bin/slime --std=c++17 || exit 1
 time clang++ -D_DEBUG -D_PROFILING -D_DONT_BREAK_ON_ERRORS src/main.cpp -g -o ./bin/slime --std=c++17 || exit 1
+# time clang++ -O3 -D_DONT_BREAK_ON_ERRORS src/main.cpp -g -o ./bin/slime --std=c++17 || exit 1
 
 echo ""
 pushd ./bin > /dev/null
diff --git a/src/built_ins.cpp b/src/built_ins.cpp
index 71f00f0..9314d2e 100644
--- a/src/built_ins.cpp
+++ b/src/built_ins.cpp
@@ -779,31 +779,27 @@ proc load_built_ins_into_environment() -> void {
         fun->value.function.body = maybe_wrap_body_in_begin(body);
         return fun;
     };
-    define_special((special-lambda args . body), "TODO") {
-        fetch(args, body);
-
-        Lisp_Object* fun;
-        try fun = Memory::create_lisp_object();
-        Memory::set_type(fun, Lisp_Object_Type::Function);
-        fun->value.function.type = Function_Type::Special_Lambda;
-
-        in_caller_env {
-            fun->value.function.parent_environment = get_current_environment();
-        }
-
-        try create_arguments_from_lambda_list_and_inject(args, fun);
-        fun->value.function.body = maybe_wrap_body_in_begin(body);
-        return fun;
-    };
+    // define_special((special-lambda args . body), "TODO") {
+    //     fetch(args, body);
+
+    //     Lisp_Object* fun;
+    //     try fun = Memory::create_lisp_object();
+    //     Memory::set_type(fun, Lisp_Object_Type::Function);
+    //     fun->value.function.type = Function_Type::Special_Lambda;
+
+    //     in_caller_env {
+    //         fun->value.function.parent_environment = get_current_environment();
+    //     }
+
+    //     try create_arguments_from_lambda_list_and_inject(args, fun);
+    //     fun->value.function.body = maybe_wrap_body_in_begin(body);
+    //     return fun;
+    // };
     define((apply fun args), "TODO") {
         fetch(fun, args);
         Lisp_Object* result;
 
-        // try assert_type(args, Lisp_Object_Type::Pair);
-        // HACK(Felix): this is probably a really nasty hack:
-        fluid_let (fun->value.function.type, Function_Type::Special_Lambda) {
-            try result = apply_arguments_to_function(args, fun);
-        }
+        try result = apply_arguments_to_function(args, fun, /*eval_args=*/false);
 
         return result;
     };
@@ -907,8 +903,8 @@ proc load_built_ins_into_environment() -> void {
             Function* fun = &n->value.function;
             if (fun->type == Function_Type::Lambda)
                 return Memory::get_or_create_lisp_object_keyword("lambda");
-            else if (fun->type == Function_Type::Special_Lambda)
-                return Memory::get_or_create_lisp_object_keyword("special-lambda");
+            // else if (fun->type == Function_Type::Special_Lambda)
+            //     return Memory::get_or_create_lisp_object_keyword("special-lambda");
             else if (fun->type == Function_Type::Macro)
                 return Memory::get_or_create_lisp_object_keyword("macro");
             else return Memory::get_or_create_lisp_object_keyword("unknown");
diff --git a/src/eval.cpp b/src/eval.cpp
index a712bd4..2bd7b56 100644
--- a/src/eval.cpp
+++ b/src/eval.cpp
@@ -1,6 +1,7 @@
 proc create_extended_environment_for_function_application(
     Lisp_Object* unevaluated_arguments,
-    Lisp_Object* function) -> Environment*
+    Lisp_Object* function,
+    bool should_evaluate) -> Environment*
 {
     profile_this;
     bool is_c_function = Memory::get_type(function) == Lisp_Object_Type::CFunction;
@@ -15,17 +16,12 @@ proc create_extended_environment_for_function_application(
     if (is_c_function) {
         new_env = Memory::create_child_environment(get_root_environment());
         arg_spec = &function->value.cFunction->args;
-        // if it is not a special form, evaluate the arguments
-        if (!function->value.cFunction->is_special_form) {
-            try arguments = eval_arguments(arguments);
-        }
     } else {
         new_env = Memory::create_child_environment(function->value.function.parent_environment);
         arg_spec = &function->value.function.args;
-        // if it is a lambda
-        if (function->value.function.type == Function_Type::Lambda) {
-            try arguments = eval_arguments(arguments);
-        }
+    }
+    if (should_evaluate) {
+        try arguments = eval_arguments(arguments);
     }
 
     // NOTE(Felix): Even though we will return the environment at the
@@ -230,12 +226,12 @@ proc create_extended_environment_for_function_application(
     return new_env;
 }
 
-proc apply_arguments_to_function(Lisp_Object* arguments, Lisp_Object* function) -> Lisp_Object* {
+proc apply_arguments_to_function(Lisp_Object* arguments, Lisp_Object* function, bool should_evaluate_args) -> Lisp_Object* {
     profile_this;
     Environment* new_env;
     Lisp_Object* result;
 
-    try new_env = create_extended_environment_for_function_application(arguments, function);
+    try new_env = create_extended_environment_for_function_application(arguments, function, should_evaluate_args);
     push_environment(new_env);
     defer {
         pop_environment();
@@ -435,7 +431,10 @@ proc eval_expr(Lisp_Object* node) -> Lisp_Object* {
         // check for c function
         if (Memory::get_type(lispOperator) == Lisp_Object_Type::CFunction) {
             Lisp_Object* result;
-            try result = apply_arguments_to_function(arguments, lispOperator);
+            try result = apply_arguments_to_function(
+                arguments,
+                lispOperator,
+                !lispOperator->value.cFunction->is_special_form);
             return result;
         }
 
@@ -446,7 +445,10 @@ proc eval_expr(Lisp_Object* node) -> Lisp_Object* {
             // we do not need.
 
             Lisp_Object* result;
-            try result = apply_arguments_to_function(arguments, lispOperator);
+            try result = apply_arguments_to_function(
+                arguments,
+                lispOperator,
+                lispOperator->value.function.type == Function_Type::Lambda);
 
             // NOTE(Felix): The parser does not understnad (import ..)
             // so it cannot expand imported macros at read time
diff --git a/src/io.cpp b/src/io.cpp
index 4981477..b27615a 100644
--- a/src/io.cpp
+++ b/src/io.cpp
@@ -313,8 +313,8 @@ proc print(Lisp_Object* node, bool print_repr = false, FILE* file = stdout) -> v
         }
         if (node->value.function.type == Function_Type::Lambda)
             fputs("[lambda]", file);
-        else if (node->value.function.type == Function_Type::Special_Lambda)
-            fputs("[special-lambda]", file);
+        // else if (node->value.function.type == Function_Type::Special_Lambda)
+            // fputs("[special-lambda]", file);
         else if (node->value.function.type == Function_Type::Macro)
             fputs("[macro]", file);
         else
diff --git a/src/structs.cpp b/src/structs.cpp
index 847b34c..1cab21f 100644
--- a/src/structs.cpp
+++ b/src/structs.cpp
@@ -52,7 +52,7 @@ enum class Lisp_Object_Flags : u64
 
 enum struct Function_Type {
     Lambda,
-    Special_Lambda,
+    // Special_Lambda,
     Macro
 };