Encontrei algumas respostas no blog do autor :
Some fans are confused about whether Daggers & Steele takes place in a 1940’s-ish noir setting or a traditional medieval one. I think it’s somewhere in the middle. I picture New Welwic, the city in which the stories take place, to be the equivalent of an early to mid 1800’s New York, but that’s not a perfect comparison.
The world of Daggers & Steele is just at the cusp of the industrial revolution. There’s water power, and as I mention in Red Hot Steele, coal has recently been discovered, but the implications of being able to burn coal for energy haven’t been discovered yet. Things like steam power and electricity are just being discovered and haven’t been implemented yet (although you’ll see some of these new discoveries appear in book three of the series, so keep your eyes peeled).
Because of the presence of magic, some scientific and technological fields are less advanced than they were in our society at similar periods in history. Physics and chemistry aren’t quite as advanced as they were in our world in the mid 1800’s, but other things, like medicine, perhaps are a little more advanced. And some technologies haven’t been invented at all, which brings me to the next question…
....
Daggers & Steele isn’t trying to be perfectly accurate to our world, because it doesn’t take place in our world.
E também tenho uma resposta oficial do autor:
As far as your question about the world, I clicked on that link, and it looks like you found the blog post where I answer a lot of those confusing tidbits. I have to admit, now that I’m four (almost five) novels in, there are probably some world building elements I might’ve done differently to make things less confusing, but I’m always the first to admit that I focus on the characters and plot first and the world gets shoed in. So what is the current world analogue? Well, it’s basically like a 1940’s era city with early 1800’s tech, if that makes sense. Plus there’s magic thrown in to pave over the rough spots.
The one thing I do wish I’d done from the beginning is include electricity, because that does seem like something they’d discovered by now. That and steam power. But if you’ve just finished book 2, you’ll soon find that I remedy those issues. I don’t want to spoil anything, though, so that’s all I’ll say.