diff --git a/ports/unix/main.c b/ports/unix/main.c
index 25f3e04fb8..03f2f357ee 100644
--- a/ports/unix/main.c
+++ b/ports/unix/main.c
@@ -440,6 +440,11 @@ MP_NOINLINE int main_(int argc, char **argv) {
     gc_init(heap, heap + heap_size);
 #endif
 
+    #if MICROPY_ENABLE_PYSTACK
+    static mp_obj_t pystack[1024];
+    mp_pystack_init(pystack, &pystack[MP_ARRAY_SIZE(pystack)]);
+    #endif
+
     mp_init();
 
     char *home = getenv("HOME");
diff --git a/ports/unix/mpthreadport.c b/ports/unix/mpthreadport.c
index 8c636a4457..baca0a2b1e 100644
--- a/ports/unix/mpthreadport.c
+++ b/ports/unix/mpthreadport.c
@@ -66,6 +66,10 @@ STATIC void mp_thread_gc(int signo, siginfo_t *info, void *context) {
         // that we don't need the extra information, enough is captured by the
         // gc_collect_regs_and_stack function above
         //gc_collect_root((void**)context, sizeof(ucontext_t) / sizeof(uintptr_t));
+        #if MICROPY_ENABLE_PYSTACK
+        void **ptrs = (void**)(void*)MP_STATE_THREAD(pystack_start);
+        gc_collect_root(ptrs, (MP_STATE_THREAD(pystack_cur) - MP_STATE_THREAD(pystack_start)) / sizeof(void*));
+        #endif
         thread_signal_done = 1;
     }
 }