diff --git a/stages/lisp0/lisp.asm b/stages/lisp0/lisp.asm
index 7fbd565..6c616e9 100644
--- a/stages/lisp0/lisp.asm
+++ b/stages/lisp0/lisp.asm
@@ -387,6 +387,19 @@ p_eq:
     lea rsi, [rel atoms]
     cmovz rax, [rsi + ATOM_TRUE * 8] ; if no pair is unequal, return "t", else return nil
     ret
+
+make_num:
+    push rdi
+    mov rdi, 16
+    mov rsi, 8
+    call alloc
+    mov dword [rax], 1          ; refcount = 1
+    pop rdi
+    mov qword [rax + 8], rdi    ; value = number
+    mov rdi, rax
+    mov rsi, OBJ_NUM
+    call obj_set_tag
+    ret
     
     ;; sum list $rdi in env $rsi
 p_add:
@@ -394,14 +407,8 @@ p_add:
     mov qword [rsp + 8], rsi    ; env
     call eval_list
     mov qword [rsp], rax        ; evaled list
-    mov rdi, 16
-    mov rsi, 8
-    call alloc
-    mov rdi, rax
-    mov dword [rdi], 1          ; refcount = 1
-    mov qword [rdi + 8], 0      ; value = 0
-    mov rsi, OBJ_NUM
-    call obj_set_tag
+    mov rdi, 0
+    call make_num
     mov rcx, rax                ; acc
     mov rdi, qword [rsp]        ; $rdi = evaled list
     mov rsi, qword [rsp + 8]    ; $rsi = env
@@ -415,14 +422,8 @@ p_sub:
     mov qword [rsp + 8], rsi    ; env
     call eval_list
     mov qword [rsp], rax        ; evaled list
-    mov rdi, 16
-    mov rsi, 8
-    call alloc
-    mov rdi, rax
-    mov dword [rdi], 1          ; refcount = 1
-    mov qword [rdi + 8], 0      ; value = 0
-    mov rsi, OBJ_NUM
-    call obj_set_tag
+    mov rdi, 0
+    call make_num
     mov rcx, rax                ; acc
     mov rdi, qword [rsp]        ; $rdi = evaled list
     mov rsi, qword [rsp + 8]    ; $rsi = env
@@ -436,14 +437,8 @@ p_mul:
     mov qword [rsp + 8], rsi    ; env
     call eval_list
     mov qword [rsp], rax        ; evaled list
-    mov rdi, 16
-    mov rsi, 8
-    call alloc
-    mov rdi, rax
-    mov dword [rdi], 1          ; refcount = 1
-    mov qword [rdi + 8], 1      ; value = 1
-    mov rsi, OBJ_NUM
-    call obj_set_tag
+    mov rdi, 1
+    call make_num
     mov rcx, rax                ; acc
     mov rdi, qword [rsp]        ; $rdi = evaled list
     mov rsi, qword [rsp + 8]    ; $rsi = env
@@ -479,17 +474,13 @@ p_rem:
 p_car:
     call eval_list
     mov rdi, rax
-    call get_car
-    mov rdi, rax
-    call get_car
+    call get_caar
     ret
 
 p_cdr:
     call eval_list
     mov rdi, rax
-    call get_car
-    mov rdi, rax
-    call get_cdr
+    call get_cadr
     ret
 
 p_not:
@@ -608,9 +599,7 @@ p_let_star_inner:
     mov qword [rsp], rdi        ; acc-env
     mov qword [rsp + 8], rsi    ; (var val)
     mov rdi, rsi
-    call get_cdr
-    mov rdi, rax
-    call get_car
+    call get_cdar
     mov rdi, rax
     mov rsi, qword [rsp]        ; acc-env
     call eval
@@ -630,9 +619,7 @@ p_let:
     sub rsp, 24
     call get_car
     mov qword [rsp], rax        ; bindings
-    call get_cdr
-    mov rdi, rax
-    call get_car
+    call get_cdar
     mov qword [rsp + 8], rax        ; body
     mov qword [rsp + 16], rsi       ; in_env
     mov rdi, qword [rsp]        ; $rdi = bindings
@@ -650,9 +637,7 @@ p_let_star:
     sub rsp, 24
     call get_car
     mov qword [rsp], rax        ; bindings
-    call get_cdr
-    mov rdi, rax
-    call get_car
+    call get_cdar
     mov qword [rsp + 8], rax        ; body
     mov qword [rsp + 16], rsi       ; in_env
     mov rdi, qword [rsp]        ; $rdi = bindings
@@ -700,6 +685,8 @@ p_str_concat:
 p_str_append:
 ;; return the nth element of a string
 p_str_nth:
+;; sets the nth element of a string to a char
+p_set_nth:
 ;; returns a new string that is a substring from a a+b of the input string
 ;; (substr "hello world" 0 5) -> "hello"
 p_str_substr: