I'd steer clear of meetups, hackathons, etc. Most of them are polluted with low signal/noise. I've found them to be a total waste of time but it's a great way to get that initial job if you don't have one already. You need things that are curated by cost, signal, or strong mutual acquaintance. Meetups usually don't have high enough obstacles to avoid pretend programmers.
The best way is engaging smart coworkers. These are the people that are going to vouch for you, shortcut the hiring process, help carve out good opportunities for you.
Other things I've done with varying success is randomly contact people off forums that I might be in a position to immediately help; inform existing contacts and ask them if they know people that I should meet out there; develop parallel hobbies like soccer, rock climbing, etc that can segue into deeper friendships. Engaging quality coworkers and these other activities tend to compound over time.