blockscout/config/runtime.exs

import Config

import Bitwise

indexer_memory_limit =
  "INDEXER_MEMORY_LIMIT"
  |> System.get_env("1")
  |> Integer.parse()
  |> case do
    {integer, ""} -> integer
    _ -> 1
  end

config :indexer,
  memory_limit: indexer_memory_limit <<< 30