purrr + ggplot: How to add titles

General
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2

I was able to answer my own question using map2, for future reference:

my_graphs <- df %>% 
  pivot_longer(names_to = "name", values_to = "value", cols = viability_percent:vcd_10_5_cells_m_l) %>%
  mutate(graph_title = paste(grouping, ":", name)) %>% 
  group_by(graph_title) %>% 
  nest() %>% 
  mutate(graphs = map2(
    data, graph_title,
    ~ {
      ggplot(.x, aes(actual_duration_of_subculture_hrs, value, group = run)) +
        geom_point() +
        geom_line() +
        ggtitle(.y)
      } 
  ))

my_graphs$graphs %>% 
  map(print)