I’m Jake an NYC based early-stage startup operator

Employee #3 at Cassidy$14M fundingCo-founder of Interviews by AI$100k+ revenueSharing my learnings on TikTok50k+ followers

Jake Rosenthal with a microphone
@jakerosenthal_

One idea has guided a lot of my career: powerful technology should be accessible to everyone. It started with no-code.

Then a friend showed me an app he’d built with an early GPT model, and I didn’t think much of it. When ChatGPT launched, I didn’t make that mistake again.

I started learning AI in public that day. That path led me to where I am now: building with AI, and sharing everything I learn along the way.

Work

Cassidy

Cassidy is an AI Agent platform that lets business teams automate work around how their organization actually operates – connecting to the tools, documents, and knowledge already in place, with the governance, permissions, and reliability IT needs to scale agents safely across the company.

I joined as employee #3 five of us in a WeWork in New York City. Over the last 2.5 years I’ve been a generalist product person, marketer, first sales engineer, and early customer success lead as we pivoted from a PLG motion to enterprise sales-led. As each team took shape, I trained its founding members on the playbooks I’d built. Today, the team is 30+ people. Revenue has grown 35x+. To date, I’ve helped close our largest customers, like OneDigital, which has onboarded 6,000 employees to Cassidy.

How one role became the next

  1. Product

    First I helped scope many of the core features – speccing, designing, and shipping whatever the product needed next.

  2. Marketing

    Then I stood up our social channels and started bringing prospects in.

  3. Sales engineer

    Those people we attracted needed demos, so I built the demo environment and became our first SE.

  4. Customer success

    Once we closed those deals, we needed them to succeed – so I built our first CSM trackers and onboarding playbooks.

  5. Product marketing

    Today my work spans a number of areas, from inbound and brand to launches, and I still jump in wherever I’m needed.

Cassidy sales enablement agent building a proposal deck
UI of Cassidy Agents
Jake filming Cassidy content at his desk
Filming Cassidy content
Cassidy brand guidelines in Figma
Brand guidelines
An Interviews by AI practice question with voice recording
UI of a user answering a generated question

Interviews by AI

A nights-and-weekends AI tool my friend and I built for interview prep. We started with a simple AI interviewer and kept shipping – better prompts, more roles, tighter feedback loops – until it became a real product people paid for. Past $100k in revenue, 80k+ users, and still growing without a full-time team behind it.

Revenue
$100k+
Users
80k+
Jake's TikTok profile with 52.5K followers and popular AI videos
Feed of some of my most popular videos

TikTok

I share what I’m learning about AI, startups, and building in public – the same lessons I’m picking up at Cassidy and on side projects. Teaching forces the clarity. The audience has grown past 50k followers, with sponsorships and partnerships along the way from teams like Zapier and Replit.

Followers
50k+
Past partners
Zapier, Replit

How I work

Early-stage operator

My formal background is in product management, but the work that fits me best is building from zero – standing up the motion, writing the first playbook, and growing into whatever the company needs next.

  • Product sense

    Spotting gaps, shaping the problem, and shipping the first version.

  • UI / UX design

    I get ideas on paper quickly so teams can react to something real, not a slide deck.

  • Storytelling

    Making the value clear enough that people move – in marketing-led and sales-led motions alike.

  • AI systems

    I build complex AI workflows end to end, for clients and in-house alike – the kind teams actually run on.

Personal

Outside of work, here’s what fills the rest of my time — soccer, music, and making drinks for people I care about.

  • Jake at the World Cup final in an Argentina jersey
    World Cup final
    Soccer

    I play and watch as much as I can. Favorites: Barça and Chelsea.

  • Jake's R&B vinyl collection on wall shelves
    Favorite vinyls
    Music

    I love R&B, collect vinyl, and sometimes write songs for fun.

  • A clover club cocktail next to a bottle of Beefeater gin
    Clover club
    Cocktails

    I make cocktails for friends and family whenever we get together.

About

So, to recap
here’s my story so far.

I grew up in Montreal and went to McGill. After school I moved to Toronto for consulting at Publicis Sapient — finance and government clients, real product work — but it didn’t take long to realize startups were more my thing.

A year into that PM role, a friend demoed a tiny app built on an early GPT model: one conversation-starter question a day. The English was fine, but it still felt like the model was mostly stringing words together. (In a lot of ways, that’s still true.) I said “oh, that’s cool” and moved on. I should have paid more attention.

When ChatGPT shipped about a year later, I treated it like a second chance. I started experimenting that day and posting everything I was learning. That turned into 50k+ followers and partnerships with Zapier and Replit.

Sharing what I knew pulled me into shipping. A friend and I built Interviews by AI on nights and weekends — 80k+ users and $100k+ in revenue with no full-time team. That work also introduced me to Justin Fineberg, who was just getting Cassidy off the ground.

Cassidy helps business teams build AI agents around how their company already runs. I joined as employee #3, five of us in a WeWork. I’ve since worn hats across product, marketing, sales engineering, and customer success, and wrote a lot of our first playbooks. I lead product marketing now, though I’m still across the business. Since I joined, revenue is up 35x+, the team is 30+, and OneDigital alone has 6,000 employees on Cassidy.