Foundler - Online hackathon weekends. Attend every other week.
Confs.tech - Open source list of tech conferences: JS / Ruby / Data etc.
CoFoundersLab - Meet 250,000+ entrepreneurs online
HackHub - Host tech events and hackathons with ease 👨💻🛠
Project Board - Team up with a co-hacker for your project
Challenge Hunt - Explore coding contests, hackathons from around the world