diff --git a/include/thread.h b/include/thread.h
index 713fe9064..2318beb4d 100644
--- a/include/thread.h
+++ b/include/thread.h
@@ -18,7 +18,7 @@
 
 #if defined (_WIN)
 
-#define hc_thread_create(t,f,a)     t = CreateThread (NULL, 0, (LPTHREAD_START_ROUTINE) &f, a, 0, NULL)
+#define hc_thread_create(t,T,f,a)   t = CreateThread (T, 0, (LPTHREAD_START_ROUTINE) &f, a, 0, NULL)
 #define hc_thread_wait(n,a)         for (u32 i = 0; i < n; i++) WaitForSingleObject ((a)[i], INFINITE)
 #define hc_thread_exit(t)           ExitThread (t)
 
@@ -29,7 +29,7 @@
 
 #elif defined (_POSIX)
 
-#define hc_thread_create(t,f,a)     pthread_create (&t, NULL, f, a)
+#define hc_thread_create(t,T,f,a)   pthread_create (&t, T, f, a)
 #define hc_thread_wait(n,a)         for (u32 i = 0; i < n; i++) pthread_join ((a)[i], NULL)
 #define hc_thread_exit(t)           pthread_exit (&t)
 
diff --git a/src/hashcat.c b/src/hashcat.c
index 067dbff5e..5cdc04285 100644
--- a/src/hashcat.c
+++ b/src/hashcat.c
@@ -179,7 +179,7 @@ static int inner2_loop (hashcat_ctx_t *hashcat_ctx)
     thread_param->hashcat_ctx = hashcat_ctx;
     thread_param->tid         = device_id;
 
-    hc_thread_create (c_threads[device_id], thread_autotune, thread_param);
+    hc_thread_create (c_threads[device_id], NULL, thread_autotune, thread_param);
   }
 
   hc_thread_wait (opencl_ctx->devices_cnt, c_threads);
@@ -230,14 +230,55 @@ static int inner2_loop (hashcat_ctx_t *hashcat_ctx)
     thread_param->hashcat_ctx = hashcat_ctx;
     thread_param->tid         = device_id;
 
+    #if defined (__APPLE__)
+    size_t stackSize;
+    pthread_attr_t tattr;
+    pthread_attr_t *attrp = NULL;
+
+    if (pthread_attr_init (&tattr) != 0)
+    {
+      event_log_error (hashcat_ctx, "Failed to initialize thread attributes");
+      return -1;
+    }
+
+    if (pthread_attr_getstacksize (&tattr, &stackSize) != 0)
+    {
+      event_log_error (hashcat_ctx, "Failed to get thread stack size");
+      return -1;
+    }
+
+    if (stackSize == 0) stackSize = PTHREAD_STACK_MIN;
+    stackSize *= 2; // mitigate OSX stack overflow
+
+    if (pthread_attr_setstacksize (&tattr, stackSize) != 0)
+    {
+      event_log_error (hashcat_ctx, "Failed to set thread stack size");
+      return -1;
+    }
+
+    attrp = &tattr;
+    #endif
+
     if (user_options_extra->wordlist_mode == WL_MODE_STDIN)
     {
-      hc_thread_create (c_threads[device_id], thread_calc_stdin, thread_param);
+      #if defined (__APPLE__)
+      hc_thread_create (c_threads[device_id], attrp, thread_calc_stdin, thread_param);
+      #else
+      hc_thread_create (c_threads[device_id], NULL, thread_calc_stdin, thread_param);
+      #endif
     }
     else
     {
-      hc_thread_create (c_threads[device_id], thread_calc, thread_param);
+      #if defined (__APPLE__)
+      hc_thread_create (c_threads[device_id], attrp, thread_calc, thread_param);
+      #else
+      hc_thread_create (c_threads[device_id], NULL, thread_calc, thread_param);
+      #endif
     }
+
+    #if defined (__APPLE__)
+    if (attrp) pthread_attr_destroy (attrp);
+    #endif
   }
 
   hc_thread_wait (opencl_ctx->devices_cnt, c_threads);
@@ -665,13 +706,13 @@ static int outer_loop (hashcat_ctx_t *hashcat_ctx)
 
   if (user_options->keyspace == false && user_options->benchmark == false && user_options->stdout_flag == false && user_options->speed_only == false)
   {
-    hc_thread_create (inner_threads[inner_threads_cnt], thread_monitor, hashcat_ctx);
+    hc_thread_create (inner_threads[inner_threads_cnt], NULL, thread_monitor, hashcat_ctx);
 
     inner_threads_cnt++;
 
     if (outcheck_ctx->enabled == true)
     {
-      hc_thread_create (inner_threads[inner_threads_cnt], thread_outfile_remove, hashcat_ctx);
+      hc_thread_create (inner_threads[inner_threads_cnt], NULL, thread_outfile_remove, hashcat_ctx);
 
       inner_threads_cnt++;
     }
diff --git a/src/hashes.c b/src/hashes.c
index 77082663e..f8ea8fdd0 100644
--- a/src/hashes.c
+++ b/src/hashes.c
@@ -231,9 +231,7 @@ void check_hash (hashcat_ctx_t *hashcat_ctx, hc_device_param_t *device_param, pl
 
   // hash
 
-  char *out_buf = (char *) hcmalloc (hashcat_ctx, HCBUFSIZ_LARGE);
-
-  if (!out_buf) return;
+  char out_buf[HCBUFSIZ_LARGE];
 
   out_buf[0] = 0;
 
@@ -278,8 +276,6 @@ void check_hash (hashcat_ctx_t *hashcat_ctx, hc_device_param_t *device_param, pl
 
   const int tmp_len = outfile_write (hashcat_ctx, out_buf, plain_ptr, plain_len, crackpos, NULL, 0, tmp_buf);
 
-  free (out_buf);
-
   outfile_write_close (hashcat_ctx);
 
   EVENT_DATA (EVENT_CRACKER_HASH_CRACKED, tmp_buf, tmp_len);
diff --git a/src/main.c b/src/main.c
index 714459165..7d3ea5d05 100644
--- a/src/main.c
+++ b/src/main.c
@@ -170,7 +170,7 @@ static void main_outerloop_starting (MAYBE_UNUSED hashcat_ctx_t *hashcat_ctx, MA
     {
       // see thread_keypress() how to access status information
 
-      hc_thread_create (hashcat_user->outer_threads[hashcat_user->outer_threads_cnt], thread_keypress, hashcat_ctx);
+      hc_thread_create (hashcat_user->outer_threads[hashcat_user->outer_threads_cnt], NULL, thread_keypress, hashcat_ctx);
 
       hashcat_user->outer_threads_cnt++;
     }
diff --git a/src/potfile.c b/src/potfile.c
index 012293c74..7b9a1afd5 100644
--- a/src/potfile.c
+++ b/src/potfile.c
@@ -256,9 +256,7 @@ void potfile_write_append (hashcat_ctx_t *hashcat_ctx, const char *out_buf, u8 *
 
   if (potfile_ctx->enabled == false) return;
 
-  char *tmp_buf = (char *) hcmalloc (hashcat_ctx, HCBUFSIZ_LARGE);
-
-  if (!tmp_buf) return;
+  char tmp_buf[HCBUFSIZ_LARGE];
 
   int tmp_len = 0;
 
@@ -302,8 +300,6 @@ void potfile_write_append (hashcat_ctx_t *hashcat_ctx, const char *out_buf, u8 *
   tmp_buf[tmp_len] = 0;
 
   fprintf (potfile_ctx->fp, "%s" EOL, tmp_buf);
-
-  free (tmp_buf);
 }
 
 int potfile_remove_parse (hashcat_ctx_t *hashcat_ctx)