function new_terminal(text_color, bg_color, error_color)
  local t = {}
  t.history,
  t.buffer,
  t.t_col,
  t.bg_col,
  t.err_col,
  t.commands,
  t.append,
  t.render 
  = 
  {},
  "",
  text_color or 11,
  bg_color or 0,
  error_color or 8,
  { cls = function(_ENV) history = {} end },

  function(_ENV, str, err)
    for line in all(split(tostr(str), "\n")) do
      add(history, { s = line, c = err and err_col or t_col }, 1)
    end
  end,

  function(_ENV, x, y, h)
    -- while there is a character in the keyboard buffer
    while stat(30) do
      -- read the next character
      local c = stat(31)
      -- backspace
      if c == "\b" then
        buffer = sub(buffer, 1, #buffer - 1)
        -- enter
      elseif c == "\r" then
        -- prevent pico-8's pop-up window
        poke(0x5f30, 1)
        append(_ENV, buffer)
        local parts = split(buffer, " ")
        buffer = ""
        local p1 = parts[1]
        if p1 ~= "" then
          if commands[p1] then
            local res, code = commands[p1](_ENV, parts)
            if (res) append(_ENV, res, code)
          else
            append(_ENV, "unknown command: " .. p1, 1)
          end
        end
      else
        buffer = buffer .. c
      end
    end

    rectfill(x, y, 127, y + h * 6, bg_col)
    -- you can remove these but then the terminal will look a bit ugly
    x += 1
    y += 1
    local lines = min(#history, h - 1)
    for i = lines, 1, -1 do
      print(history[i].s, x, y + (lines - i) * 6, history[i].c)
    end
    print(">" .. buffer .. "_", x, y + lines * 6, t_col)
  end

  return setmetatable(t, { __index = _ENV })
end

-- example usage
function _init()
  -- turn on the dev kit so we can access the keyboard
  poke(0x5f2d, 0x1)

  term = new_terminal()

  -- attach a command to the terminal
  term.commands.hello = function(_ENV, args)
    return "hello" .. (args[2] and " " .. args[2] or "") .. "!"
  end

  -- attach a command with multiline results
  term.commands.ls = function()
    return "a\nb\nc"
  end

  -- attach a command with possible error results
  term.commands.ok = function(_ENV, args)
    local ok = rnd() < .5
    return ok and "success" or "error", not ok
  end
end

function _draw()
  cls(1)
  -- draw the terminal starting from y, y with height in rows (each row is 6 pixel tall)
  -- the terminal always spans to the right edge of the screen
  term:render(0, 22, 10)
end