Unthinkable (even though it's really kinda of an ehh movie), or Kevin Bacon a movie like Stir of Echoes and it's pretty obvious they did those for love of the craft, and not a paycheck.
Anyway, Citadel. I guess it's Children of the Corn meets Taken, with a dash of Alan Wake on the side. It's certainly got a fine atmosphere, a couple of nice fright moments, and I thought Aneurin Bernard was terrific in the lead role, but ultimately it was just a little too predictable for me to give it a full recommendation. When the nurse gets killed, I literally said aloud "And you're gonna die" moments beforehand. The end resolution was also quite predictable, and likewise the priest's entire character arc. So 5/10 or so.
I love minimalist stories -- you can't really say it's a minimalist production, but there are really only 5 characters in the story, one of whom is an infant. So I found it worth the watch on that note. Wouldn't really call it re-watchable, though.
It perhaps gets a few points, though, for an accurate portrayal of agoraphobia. Most of the time when agoraphobia is portrayed in media, the character in question is a recluse who never ever leaves his or her home. In this movie, Tommy does come and go from home. He's just scared ****less when he leaves the house and makes a beeline for his font door when it's in view coming back. That's a much more realistic depiction of what agoraphobia really is. The "lock yourself in from anything in the outside world" form does exist, but it's extreme and rare.