Solo Founders #3: Solo Hacker Wanted, Browserbase's $40M Series B, the $80M sale of Base44, and early teammates as a solo founder

Hey Solo Founders,

Two months ago, we tweeted, “Solo founders are underestimated. Let’s change that.”

Since then, we’ve:

• Kicked off the first Solo Founders Program in San Francisco (<1% acceptance rate)

• Watched our very first SFP company raise millions

• Received thousands of new solo founder applications

• Welcomed 5,000 of you to the mission on X and 2,500 through this newsletter

The momentum is real — together, we’re rewriting how great companies get built.

Now, onto the stories: we’re hiring a Solo Hacker, Browserbase’s $40M Series B, an $80M exit in just six months, and a fresh perspective on early teammates as a solo founder.

We rarely hire, but we’ve opened one seat in SF for a builder who wants to help more founders win. Join us.

Solo founder Paul Klein IV nets a $40M Series B for Browserbase

Paul Klein IV announced Browserbase just 16 months ago; the company has since grown to ~30 employees and yesterday announced a $40M Series B at a $300M valuation led by Notable Capital, with Kleiner Perkins and CRV doubling down.

In the same breath, Browserbase unveiled Director — a no-code layer that converts plain-English instructions into always-on, cloud-hosted, headless browser automations.

Starter projects you could ship this weekend

1. Early-adopter hunter – Each morning, have Director search Product Hunt, Hacker News, and key subreddits for posts or comments containing your product’s keywords (e.g., “meeting recorder,” “AI bookkeeping”). Then have it scrape the poster’s handle, profile link, and context snippet into Airtable so you have a fresh pipeline of users to DM.

2. Competitor pricing tracker — check rivals’ pricing pages daily and post diffs into Slack so you never miss a change.

3. Daily metrics digest — scrape your Stripe dashboard, Mixpanel, and GA, then email yourself a one-pager of key numbers every morning.

These are ideas we’ve prototyped internally — feel free to adapt or remix. If you build something cool, reply, and we’ll feature it in the next issue!

Solo founder → 6 months → $80M sale to Wix

Solo founder Maor Shlomo just sold his new company, Base44, to Wix for $80M — only six months after he wrote the first lines of code on a post–reserve–duty backpacking trip - and without a dollar of external funding. Shlomo isn’t new to startups: he previously co-founded Explorium, raised $125 million, and then stepped away in 2023 to serve in the Israeli military reserves.

What’s wild

• Profitable by month five. Base44 reached 250K users and $189K in profit in May.

• Vibe coding differentiation. From a single chat prompt, the AI generates a complete app — DB, authentication, storage, and analytics — without requiring any code.

• Frugal tech edge. He switched from OpenAI to Anthropic’s Claude on AWS to reduce compute costs and maintain speed.

• Community flywheel. Shlomo hosted a 24-hour “Base4Good” hackathon and posted every metric, turning followers into users and, eventually, an acquirer.

• Enterprise runway. Even before the sale, Base44 rolled out a Team Plan with SSO, SOC 2, and custom database controls, as well as partnerships with Similarweb and eToro.

His words on the deal: “The scale we need isn’t something we can grow into organically… If we got this far bootstrapped, imagine what we can do with Wix’s resources.”

Big congrats to Shlomo and the Base44 crew — another reminder of how far a focused solo founder can go.

How Nathan Baschez turns early employees into true partners

Nathan Baschez — the solo founder of AI-writing tool Lex — dropped by our SF dinner last week. He had a ton of amazing insights to share, but one that we thought might be worth sharing with the group is his perspective on early teammates as a solo founder. If you don’t know Nathan, when he launched Lex, 25,000 people signed up within a day, and he quickly landed a $2.75M seed round led by True Ventures.

Nathan’s three-part alignment playbook:

• Share the upside. Early hires can get more equity when you don’t have a co-founder, so they feel like real partners from day one.

• Keep pay stress-free. He pairs that equity ownership with reasonable salaries so teammates can focus on shipping.

• Make exits graceful. If a teammate chooses a new path, Nathan tries his best to help with intros or advice. And it’s far less disruptive when an employee leaves than it's to lose a co-founder.

Nathan shows how allocating the equity you’d usually reserve for a co-founder into thoughtful grants for your first hires can forge a tight, committed team from day one.

Huge thanks to Nathan for swinging by to meet the SFP cohort and for being such an active part of the solo founder community!

We asked the SFP cohort if they had any quick lessons from that past week or two that might be interesting/valuable for the community:

Dhravya of Supermemory says, “The only way to win is to be prolific in hiring, building, and selling,” while Namanyay of Giga was reminded by a mentor to “smile when things get tough” because it actually tricks your brain into enjoying the struggle.

That’s a wrap for now. If you liked what you read, share it with a friend and point them here to subscribe.

— Julian, Kieran, and the SFP team