My friend invited me the company he works as a dev with much higher salary than my current shitty work for the third time, cannot leave current this because of technical dept.

I am the only backend dev right now and if I leave, things will go worse.

Open up with your current boss, tell him that a better job offer appeared and you are seriously thinking about it, and if your conditions don't get any better at your current job, you're going for it.

If you feel bad to abandon your current project and if you really want to take your friend's offer, give to your boss a month or so to find someone else to continue your job, meanwhile, take the offer, sign a contract and state that you can start working in 30 days, so they can't play you too.

Don't let anyone or anything be in your way to profissional/personal success.

Will do, thanks for the advice.

I agree with @wesaka, sound advice.

@orkhanfarmanli that's a bit like staying with your boyfriend that beats you because you're afraid he couldn't do his laundry alone :/

@willol hahaha that's so weird but true :D