diff --git a/sysmisc.c b/sysmisc.c
index 1bc27d2..3eed84a 100644
--- a/sysmisc.c
+++ b/sysmisc.c
@@ -390,12 +390,11 @@ enum {
   Confwflag_add_newline = 1 << 0,
 };
 
-void ezconf_write_start(Ezconf_write *ezcw, Confopt_w *opts, size_t optscount) {
-  for (size_t i = 0; i < optscount; i++)
-    opts[i].written = 0;
+void ezconf_write_start(Ezconf_write *ezcw, Confopt_w *optsbuffer,
+                        size_t buffercap) {
   *ezcw = (Ezconf_write){0};
-  ezcw->opts = opts;
-  ezcw->optscount = optscount;
+  ezcw->opts = optsbuffer;
+  ezcw->optscap = buffercap;
   Ezconf_write_error error = Ezconf_write_unknown_error;
   switch (conf_save_start(&ezcw->save)) {
   case Conf_save_start_ok:
@@ -426,7 +425,13 @@ void ezconf_write_start(Ezconf_write *ezcw, Confopt_w *opts, size_t optscount) {
   }
   ezcw->error = error;
 }
-
+void ezconf_write_addopt(Ezconf_write *ezcw, char const *key, intptr_t id) {
+  size_t count = ezcw->optscount, cap = ezcw->optscap;
+  if (count == cap)
+    return;
+  ezcw->opts[count] = (Confopt_w){.name = key, .id = id, .written = 0};
+  ezcw->optscount = count + 1;
+}
 bool ezconf_write_step(Ezconf_write *ezcw) {
   U32 stateflags = ezcw->stateflags;
   FILE *origfile = ezcw->save.origfile, *tempfile = ezcw->save.tempfile;
diff --git a/sysmisc.h b/sysmisc.h
index 0e8dd1b..d1eec99 100644
--- a/sysmisc.h
+++ b/sysmisc.h
@@ -117,12 +117,14 @@ typedef struct {
 typedef struct {
   Conf_save save;
   Confopt_w *opts;
-  size_t optscount;
+  size_t optscount, optscap;
   intptr_t optid;
   FILE *file;
   Ezconf_write_error error;
   U32 stateflags;
 } Ezconf_write;
 
-void ezconf_write_start(Ezconf_write *ezcw, Confopt_w *opts, size_t optscount);
+void ezconf_write_start(Ezconf_write *ezcw, Confopt_w *optsbuffer,
+                        size_t buffercap);
+void ezconf_write_addopt(Ezconf_write *ezcw, char const *key, intptr_t id);
 bool ezconf_write_step(Ezconf_write *ezcw);
diff --git a/tui_main.c b/tui_main.c
index 5981e1c..23cff84 100644
--- a/tui_main.c
+++ b/tui_main.c
@@ -2398,8 +2398,9 @@ Prefs_load_error prefs_load_from_conf_file(Prefs *p) {
 void save_prefs_with_error_message(Midi_mode const *midi_mode, int softmargin_y,
                                    int softmargin_x,
                                    bool softmargins_touched_by_user) {
-  Confopt_w wopts[Confoptslen];
-  Usz i = 0;
+  Confopt_w optsbuff[Confoptslen];
+  Ezconf_write ez;
+  ezconf_write_start(&ez, optsbuff, ORCA_ARRAY_COUNTOF(optsbuff));
   oso *midi_output_device_name = NULL;
   switch (midi_mode->any.type) {
   case Midi_mode_type_null:
@@ -2416,19 +2417,14 @@ void save_prefs_with_error_message(Midi_mode const *midi_mode, int softmargin_y,
       osowipe(&midi_output_device_name);
       break;
     }
-    wopts[i].name = confopts[Confopt_portmidi_output_device];
-    wopts[i].id = Confopt_portmidi_output_device;
-    i++;
+    ezconf_write_addopt(&ez, confopts[Confopt_portmidi_output_device],
+                        Confopt_portmidi_output_device);
   } break;
 #endif
   }
   if (softmargins_touched_by_user) {
-    wopts[i].name = confopts[Confopt_margins];
-    wopts[i].id = Confopt_margins;
-    i++;
+    ezconf_write_addopt(&ez, confopts[Confopt_margins], Confopt_margins);
   }
-  Ezconf_write ez;
-  ezconf_write_start(&ez, wopts, i);
   while (ezconf_write_step(&ez)) {
     switch (ez.optid) {
 #ifdef FEAT_PORTMIDI