I suggest you look up some of the providers contact details (eg push gaming, light and wonder etc) and contact their support email. I can guarantee no one person ever writes a slot. There will be ui specialist, graphics designers, coders, etc. You will notice there aren’t actually many different types of games because the algorithms to calculate percentages etc likely require masters degree in maths. You’ll notice say 5 years ago there was a massive release of mega ways games. All from different providers but the mega ways technology was licensed from big time gaming. In the States they have a lot of these lock and link type games from different providers so think about where your skills are best suited. Nb I never worked in that industry but I spent 15 years as programmer analyst and learnt to recognise my strengths and weaknesses and it wasn’t in ui!