Writesonic: why I invested and what the Y Combinator startup does today

Writesonic is one of the 32 startups I've invested in, and one of the ones doing best. I came in in 2021, when it was in Y Combinator's S21 batch. Here's how I found it, why I said yes and what it does today.

What Writesonic is

Writesonic was founded by Samanyou Garg in San Francisco. When it got into Y Combinator, its product helped companies write marketing copy with AI: ads, product descriptions, blog posts.

Today it does something else. It's a GEO (generative engine optimization) platform: it helps a brand see how often it shows up in answers from ChatGPT, Claude, Gemini and Perplexity, and improve that spot. It's what SEO does for Google, but for AI answers.

How I found it

Nobody introduced me. Like with Plerk, I found it going through the companies getting into Y Combinator.

I liked it and messaged the founder directly. On Instagram.

No intro, no syndicate, no fund in between. One DM. That's how I've gotten into several of my investments: I go through each batch, see what interests me and find the founder wherever they are.

Why I invested

Because they were going after a good problem. Writing marketing copy takes time and money, and almost every company needs it every week.

That's the first thing I look for in any investment. When I went back over the 14 startups in my portfolio that shut down, the clearest pattern was that almost none of them were solving a real problem. Writesonic was.

How much I invested

My usual check: around $25,000, early stage, during Y Combinator.

I haven't put more money in later rounds.

What happened next: the pivot to GEO

When I invested, ChatGPT didn't exist. It came out at the end of 2022, and writing copy with AI went from rare to something anyone could do for free.

Writesonic moved. First it launched Chatsonic, its own AI chat, and then it pivoted to GEO. The logic holds up: if more and more people ask ChatGPT instead of searching Google, brands need to know whether they show up in those answers.

The underlying problem is the same as in 2021: helping companies reach customers without spending a fortune on marketing. What changed is the tool.

To me that's the most interesting part of this investment. You invest in a team and a problem, not in the day-one product. The product almost always changes.

How it's doing today

It has solid ARR and keeps growing. It's one of the six doing best in my portfolio, along with Tovala, Filadd, Fitia, Cero and Nectome.

In September 2024 its founder shared publicly that they were at several million dollars in ARR, with more than 10 million registered users, and that they had raised $2.6 million without needing to touch it.

No exit yet. My only exit is still Plerk, and that wasn't in cash either.

What I take from Writesonic

Two things.

Messaging the founder directly works. You don't need an intro. If you like a company, find the founder and tell them why.

Invest in the problem. If the problem is real and the team moves fast, the product can change completely and the company keeps growing.

The full portfolio is in Investments. What I learned from the ones that shut down is in 32 startup investments.

FAQ

Did Carlos Gotlib invest in Writesonic? Yes. I invested in 2021, when Writesonic was in Y Combinator's S21 batch.

How much did Carlos Gotlib invest in Writesonic? Around $25,000, my usual check. I haven't invested in later rounds.

What does Writesonic do today? It's a GEO platform: it helps brands measure and improve how often they show up in answers from ChatGPT, Claude, Gemini and Perplexity. It started as a tool for writing marketing copy with AI.

Who founded Writesonic? Samanyou Garg, in San Francisco.

Has Writesonic had an exit? No. It's still active and growing.