tab <- Table$create(a=1:4, b=6:9)

tab %>% 
  mutate(counter = 1) %>% 
  summarize(count = sum(counter))

Table
1 rows x 1 columns
$count <double>

tab %>% 
  mutate(counter = 1) %>% 
  group_by(a) %>% 
  summarize(count = sum(counter))

 *** caught segfault ***
address 0x0, cause 'invalid permissions'

Traceback:
 1: .Call(`_arrow_ExecPlan_run`, plan, final_node)
 2: ExecPlan_run(self, node)
 3: plan$Run(final_node)
 4: do_exec_plan(.data, group_vars = dplyr::group_vars(.data))
 5: do_arrow_summarize(.data, ...)
...