Peer labs started in Amsterdam as a part of the Appsterdam community. Sometimes they go by a different name, like "side-project Saturdays", or maybe they don't have a name at all. The important thing is just that they exist!
Starting a peer lab is easier than you might think – you can read about a developer's experiences starting one here. It's a very fun and rewarding experience, and with just four steps you can help your local developer community flourish and grow. Just remember to keep a positive attitude and you'll do awesome!
When are you free to do this? Do you like working in the evenings? Awesome! Do it then. Are Sunday afternoons your jam? Sweet. Whenever works for you.
This is easier than it might sound. As an organizer, you need a space that's convenient for you. I use my workplace because I live nearby. Some organizers use a café by their apartments. Anywhere that has wifi. Pick a place that works for your time – for example, if you're meeting in the morning, a place with coffee is a good idea.
Tweet it, send it to some friends, whatever works. You could ask your employer or a sponsor to pay for a Meetup account (ask them for pizza money, too). Send details to popular developers in your city and ask them to help spread the word.
Add your peer lab to this site by sending a pull request to our GitHub repo. Instructions are in the readme, just open an issue if you have questions.
Most of success is just showing up. Peer labs are no exception. It's important for you as an organizer to just be there. Finding a co-organizer can help, too, so ask around. Don't worry too much about attracting participants, even if it's just you, at least you've got a nice time to code every week, and hopefully you'll meet some other people to jam with.
One last important note: your peer lab should have a stated Code of Conduct. This helps let everyone know that they're welcome in the space you're creating. The Contributor Covenant is what we recommend.