simple timeout script written in nim for a ZNC bouncer. After 10 minutes of inactivity it sends "AWAY :<nick> is currently afk (set by timeoutbot)". After becoming active again it sends "AWAY" to the server. To change it to suit your needs, edit all of the top const variables to their appropriate values.

timeout.nim

import irc, asyncdispatch, posix

const
  time: cint = 600
  server: string = "dtscode.io"
  port: int = 3038
  nick: string = "dtscode"
  user: string = "dtscode"
  real: string = "nchambers - dtscode.io"
  pass: string = "REDACTED_PASSWORD"
  channels: seq[string] = @[]

var away: bool = false

proc onIrcEvent(client: PAsyncIrc, event: TIrcEvent) {.async.} =
  case event.typ
  of EvConnected:
    nil
  of EvDisconnected, EvTimeout:
    await client.reconnect()
  of EvMsg:
    if len(event.params) > 1 and event.params[1] == "You have been marked as being away":
      away = true
      discard alarm(0)

    elif event.host == "dtscode.io":
      await send(client, "AWAY")
      away = false
      discard alarm(time)

    elif len(event.params) > 1 and event.params[1] == "You are no longer marked as being away":
      away = false
      discard alarm(time)

    echo(event.raw)

var client = newAsyncIrc(server, port.Port, nick, user, real, pass, channels, true, onIrcEvent)

proc make_away(signal: cint) {.noconv.} =
  if not away:
    asyncCheck client.send("AWAY :" & nick & " is currently afk (set by timeoutbot)")
    away = true

signal(SIGALRM, make_away)
discard alarm(time)

asyncCheck client.run()
runForever()