Targeted interview prep...what does that mean? I'm sure there is a lot of prep you are doing that applies to a bunch of different jobs. Grinding out some algorithms(icky but unfortunately necessary), Prepping your behavioral question answers with the STAR method etc etc. You can however do some additional prep specific to each of the companies you are applying for.
Here are some steps I take when I get invited to start interviewing at a company:
This might not always work out with smaller start-ups but a great place to start is Glassdoor. There is an interview section where other candidates share their experience doing interviews with the company. It will give you an insight into their process and sometimes people even drop in the specific questions they got during the interview. I got quite lucky with my job someone mentioned the kind of things they were tasked with doing and I reviewed those before going in and got the job. Glassdoor is an incredible resource and I definitely recommend doing at least a quick check before going into your interview.
Are you interviewing for a company like Twilio that has public APIs? Awesome build something super quick with one of their API's and talk about it at the interview. Does the company have open source projects that they put out? Try using one of them or playing around with one. I was once asked if I had ever used a company's open-source projects during an interview and had to respond in the negative.
If you're going for a web dev position go to their website and open up the console. I've seen some company's leave some random easter eggs in there and if you can bring that up in a conversation you're showing two things - maybe you like their sense of humor and that you're a curious person who likes exploring code. Conversely, if there is a not so great easter egg in there, another thing I've found, you might know it's not worth moving forward with this company.
These are some things I like doing to prepare specifically for certain companies I interview with. If you have any other suggestions or anything you like doing drop them suggestions below!
If you're a new dev looking for their first job check out the ebook I am working on: