Aha! Well, most likely you've got your Pi running a flavor of Linux. (At least, I haven't heard of any running a non-Linux OS.) Hmm.

Pierogi itself does not use the LIRC server. One of the reasons I created the app was that I don't agree with some of the fundamental design decisions of the LIRC daemon; in particular, it's mainly designed to receive IR data, not send it. (In fact, you don't need a daemon if all you are doing is sending data; there's no point in sitting and waiting to receive commands.) Anyway, Pierogi wants to talk directly to the device driver itself.

The easiest solution would be to create an intermediary, something which listens for commands over the (wifi) network, and translates those into timing values to switch the IR on and off. The LIRC daemon works, as you say, as exactly such an intermediary. Unfortunately, so far as I know, the LIRC daemon can only listen for the commands for a single keyset at a time. And those commands are passed as keywords, not as timing values.

You could also create your own intermediary. That's what I'd do, to set up a daemon that simply listened for timing values and passed them on to the IR device, without worrying about keysets. That'd make things a lot easier for Pierogi, anyway.

In either case, before you can set up either LIRC or Pierogi, you'd need to construct a device driver for your IR hardware. I've not actually done this myself before, but from what I understand it isn't too hard to do...