Slack channels and Linkedin startup group/events

Hi guys,

I'm Ramphis Reyes, founder of ARCTOS, a digital marketing agency providing web/branding solutions to validate/test ideas for Startups Class A, B, Seed & Pre-Seed level companies in the US.

I'm looking into joining some Slack channels and LinkedIn Groups in order to have more exposure to our agency.

We offer unlimited requests and revisions to validate their SaaS business.

Which Slack channels or Linkedin Groups do you recommend in order to reach people looking to build new ideas or improve their existing ones?

Also if you can enlight me about some events that people are willing to attend this year.

Best regards,