Founders Nation - Find or become a startup cofounder
Foundler - Online hackathon weekends. Attend every other week.
Find A Maker - find a partner for your next project
CoFoundersLab - Meet 250,000+ entrepreneurs online
HackHub - Host tech events and hackathons with ease 👨💻🛠
Co-founder Question Cards - Questions to ask your co-founder to know each other better.