Phone, then two onsites. I don't think you should apply. Either they're not hiring or their bar for hire is higher than their current engineering level - meaning their engineers wouldn't pass their own bar to begin with. I can tell by the questions they're asking me regarding the algorithm / solution. They said they all liked me, I answered every question with optimal solution, but still decided not to proceed because of communication issues. They also messed up one of the interviews (one of them was supposed to be non-technical, but all were technical) and it feels like they're using it against me.

Applied online, the whole process took about 2 weeks. Weird that i only get to talk to 1 person verbally throughout the entire process. Round 1. Online coding question. all of them are very easy, i mean shockingly easy for a senior position. Round 2. Email with HR, this is where i found weird since it's usually a 30 minute call to gather some information, but it's done via email. Round 3. onsite/remote onsite with an engineer. This is where things go super odd. I had 2 questions, one is to implement a strstr in Java without using indexOf, i described the naive way and the KMP, and i was told to just implement the naive way which i did, and got a slight mistake in the first go, and corrected myself, i did ask if it's the style or the speed that they were looking for, but the interviewer said just do which ever way i wanted. Second question was about implementing a feature that there is a bunch of items, each of them can be stacked together, and the maximum number of items in the stack is provided as parameter, and you can only stack the same items together. Each item is given a sale price. now implement a method given the item information, stacking information and number of stacks you can have in the inventory, find the most value you can fit in the inventory. I finished the question and got stopped halfway through writing tests, and the interviewer said i got it right, there's no need for more tests. which i took as a good sign considering it is quite a simple feature. The tail spin comes the next day, i got an email from the recruiter saying that they don't want to continue the interview process and there was no feedback provided. I was pretty shocked considering i've got full mark in the online test, and i was told by the interviewer that both of my interview questions were right during the interview. So i wrote back asking for reasons, and i got a email, generated from the system, saying that i have problem with my CS fundamental. This is clearly not the reason behind this, so i chased it up with the recruiter and ask for more specific feedback then no one ever respond again. Have to say, i should not be surprised about their lack of professionalism after reading the interview reviews from glassdoor, so if you are applying or thinking of applying for pocket gems, make sure you think twice and be prepared for rejections that may come from nowhere.