Sales.co
sales.co
Done-for-you cold email and AI-assisted lead generation for B2B companies, co-founded with Ryan Doyle.

Mini-tool serving tweet inspiration prompts; acquired by Tweet Hunter.
Exit story: How Jakob Greenfeld Sold What to Tweet to Tweet Hunter (2021) →
Visit What to Tweet ↗Mini-tool serving tweet inspiration prompts; acquired by Tweet Hunter. What to Tweet is a marketing & seo tools product built by indie maker Jakob Greenfeld, launched in 2020. What to Tweet has since been acquired.
sales.co
Done-for-you cold email and AI-assisted lead generation for B2B companies, co-founded with Ryan Doyle.
founderflywheel.com
Research-as-a-service newsletter for entrepreneurs.
opportunities.so
Newsletter of researched business opportunities and ideas for entrepreneurs.
newsletterspy.io
Data on Substack newsletters and what is growing.
Data tool that analyzed what was selling on Gumroad.
Data on indie products for makers and indie investors.
Micro-SaaS surfacing early trend signals for investors, entrepreneurs and marketers.
What to Tweet is a marketing & seo tools product: Mini-tool serving tweet inspiration prompts; acquired by Tweet Hunter.
What to Tweet was made by Jakob Greenfeld, Physicist turned permissionless entrepreneur, co-founder of Sales.co. It launched in 2020. Jakob Greenfeld has also built Sales.co, Founder Flywheel, Opportunities.so, Newsletter Spy.
What to Tweet has been acquired. It is no longer owned by Jakob Greenfeld, who built it as an indie maker.
seobotai.com
Fully autonomous SEO robot with AI agents that researches keywords and writes, publishes and interlinks blog articles.
listingbott.com
Lists your product on hundreds of relevant directories in one click to earn backlinks and domain rating.
indexrusher.com
Gets your web pages indexed by Google faster.
tinyadz.com
B2B ad network for tech products and indie sites.
His first SaaS, which reached about $4K MRR before COVID ended it.
outrank.so
Generates and publishes SEO articles to grow organic traffic on autopilot.