This week, we trace Braze’s decade-long journey from an early bet on mobile to IPO.

Braze’s Path to Product-Market Fit — How to Build for a Market That Doesn’t Exist Yet

Page the calendar back to 2011, and the state of mobile looks a lot like AI in 2025. The release of the iPhone brought mobile to the mainstream in 2007 much like ChatGPT did for AI in 2022. Within a few years, the first wave of consumers had caught on — but existing businesses hadn’t yet figured out how (or why) to treat mobile as a growth lever.

That year, a few recent M.I.T. grads and Bridgewater alums had the idea to help mobile devs monetize their apps. They called their new startup Appboy (before later rebranding to Braze).

There was just one problem: “The market wasn't ready for us to sell to it yet,” says Bill Magnuson, Braze’s co-founder who was originally CTO before becoming CEO in 2016. You could scroll Facebook or play Angry Birds on your phone, but it would be a while before major enterprises like banks and retailers — the types of customers Braze now has an extensive roster of — set up shop in the App Store.

“Our best answer to ‘why now?’ was to get a multi-year head start on something we had strong conviction in. But not everyone agreed with that. In the early days, it was sometimes difficult to maintain that full conviction because of how long it took,” he says.

Today, the customer engagement platform pulls in hundreds of millions in of dollars in Committed Annual Recurring Revenue (CARR) and has a multi-billion dollar market cap and a listing on Nasdaq. But the company’s path to get there was lined with doubts and detours:

• When they first launched a public beta in 2012, most of the 1,000 users that signed up churned because many of those apps went under (their ICP of mobile marketers wouldn’t emerge for another few years)
• Investors told them to build for gaming apps instead of building a horizontal platform, because at the time, that’s where all the money was
• It wasn’t until the Braze team raised a Series D that they received more than one term sheet

It took several years after founding to see the first meaningful sparks of traction — signing and retaining enterprise customers who were early experimenters with mobile marketing.

In the latest installment in our Paths to Product-Market Fit series, Magnuson and Chief Product Officer and early employee Kevin Wang take us through how they built a product for a market that was just starting to coalesce.

“A lot of people fall for the headlines of this or that acquisition happening quickly and in the early years,” says Magnuson. “So when they guess how long it takes on average for a company to IPO, they grossly underestimate it.” In Braze's case, it took a full decade from founding to IPO.

Braze’s story serves as a reminder that no matter how fast today’s buzziest startups zoom to revenue milestones in record timelines, building an enduring company is a long game. Magnuson and Wang share plenty of tactics and reflections for builders eyeing a market that’s still in its infancy.

Thanks, as always, for reading and sharing!

-The Review Editors

Recommended resources:

-Tips for choosing the right OKRs for early-stage startups

-Inspo for a “how to work with me” guide (and check out this Review article for more pointers on how to write your own)

This week, we’re publishing the third installment in our new series on going from 0 to multiple millions in ARR. Today’s guide is all about how now-massively successful startups found their initial ICP.

0-$5M: How to Identify Your ICP — Lessons from Vanta, Clay, Retool

In the early days of building a startup, there’s a certain dopamine hit that comes from hearing:

"This product is so powerful. We could use this for all kinds of things!"

But that excitement can quickly fade into something more dangerous: Inconsistent usage. Feature creep. A tangled roadmap that tries to be everything for everyone — and ends up serving no one particularly well.

That’s exactly what happened to Clay, for example. Early users were enthusiastic, but their use cases were wildly different — from recruiters to accountants to engineers. And Clay tried to hang onto each and every one of these early customers. In turn, it caused a years-long spiral as the team kept switching who they were building for, chasing the loudest feedback and watching momentum stall again and again.

In the latest installment of our 0-$5M series with First Round Partner Meka Asonye, we dig into how now-massively successful startups finally cracked the code on their ICP. In addition to Kareem Amin, here’s who else you’ll learn from:

• Christina Cacioppo, co-founder and CEO of Vanta
• David Hsu, founder and CEO of Retool
• Waseem Daher, co-founder and CEO of Pilot
• Bryant Chou, co-founder and Chief Architect of Webflow
• Eric Berg, former Chief Product Officer at Okta
• Hubert Palan, founder and CEO of Productboard
• Mike Molinet, founder of Branch and now building Thena

Small spoiler alert here: For most of these startups, their first crack at an ICP was way off the mark. We unpack the pivotal moments that happened behind the scenes to find ICP clarity, like:

• How Vanta’s aha moment came from a single conversation with an engineer at Figma
• How Retool invalidated their initial ICP hypotheses — and found a Fortune 250 customer instead
• How Productboard used green/yellow/red scoring to rein patterns emerge

If you’re in the early stages of building — or trying to rein in a sprawling roadmap — this one’s worth the read. Because the wrong customer doesn’t just waste your time, they shape your product in all the wrong ways.

Thanks, as always, for reading and sharing!

-The Review Editors

Recommended resources:

-Is your AI idea any good? A 5-question stress test

-The GAINS comp negotiation playbook.

🎙️ On the In Depth podcast:

The story of Rick Song and Persona is not the standard founder story. Rick was incredibly reluctant to leave Square and become a startup founder (his mantra at the time was "Life's too short to try new things," he joked). He set out to invalidate the idea early on, convinced that a horizontal approach to identity verification simply wouldn't work.

Rick gets candid about imposter syndrome, the evolution from engineering to commercial thinking and his vision for who we are online in an AI-dominated world.

From reluctant founder to $2B valuation: The story of Persona | Rick Song (Co-founder and CEO)

Rick Song is the co-founder and CEO of Persona, the identity verification platform used by some of the world’s largest companies. Before starting Persona, Rick worked on identity fraud and risk products at Square, which laid the groundwork for what would become Persona’s highly technical, horizontal platform. Since

First Round ReviewFirst Round Staff

This week, we’re tackling the work before the work — how to start building your emotional toolkit for the founder journey ahead.

Thinking About Taking the Founder Leap? Here’s How to Prep for the Emotional Gauntlet

Psychologist Dr. Emily Anhalt was sitting in a coaching session with a founder who just finished a successful Series A raise. It was a major milestone — but instead of feeling triumphant and celebratory, the founder was more anxious than ever. “I thought that once we raised money, the stress would ease,” the founder said. “But now I’m terrified of letting down our investors, my team and our customers.”

In her 15 years of experience as a therapist and executive coach, Dr. Anhalt has sat across from countless founders echoing the same sentiment. They certainly expect that starting a company will bring its fair share of lows where they are forced to just grind it out, against all odds. But what is much less expected is the realization that achieving one goal becomes the starting line for ten new ones.

That’s why she’s adamant that founders who are early in their journey start taking this work seriously now, or even better, before they put “Something New” at the top of your LinkedIn profile.

“Think of it as creating shock absorbers for your emotional vehicle — they don't eliminate the bumps in the road, but they make them more manageable,” says Anhalt.

On the Review, she picks up the pen and sketches the four steps for getting started. Here’s a preview of what’s in store:

Step 1: Identify your fears so you can face them. “When you’re riddled with anxiety about taking the founder leap, start by pinpointing the fear and naming it. Is it financial instability? Judgment from others? Torpedoing a relationship with a friend-turned-co-founder? Not being able to raise funding? Getting specific makes it easier to take tactical steps to address that specific fear.”

Step 2: Figure out your “why to address uncertainty. “Ask yourself: In five years, will I regret not trying more than trying and it not working?”

Step 3: Create systems for longer-term resilience. “Don't wait until you're burning out to create boundaries or for time to open up to take care of yourself. Put structures in place before you need them. The most successful founders I work with aren't the ones who can push through anything — they're the ones who build sustainable practices.”

Step 4: Find circles of trust to manage founder loneliness. “There's a fundamental shift that happens — from fear about uncertainty (’Will this work?’) to pressure about sustainability (’How do I keep this going?’).”

You can also pick up her brand-new book, “Flex Your Feelings: Train Your Brain to Develop the 7 Traits of Emotional Fitness,” on virtual and physical bookshelves today.

Thanks, as always, for reading and sharing!

-The Review Editors

Recommended resources:

-This conversation between Stripe CEO Patrick Collison and Sir Jony Ive (former Chief Design Officer at Apple).

-Startups rarely die from bad code. They die from false confidence.

This week, we assembled advice from an all-star group of founders, product leaders and first marketing hires for a tactical guide to taste.

The Unsung Ingredient in Stripe, Square and Linear’s Success: Taste

Taste is trending — in Substack newsletters, X replies, and LinkedIn posts, conversations about craft are spilling out from the artistic world and popping up in tech circles more than ever.

There have long been companies (like Apple and Stripe) revered for their taste and quality. So why does it seem like the rest of tech is just starting to catch on now over the past couple of years?

To put it simply (and to borrow from product designer Shane Levine), code is no longer a moat. We are living in the most accessible time in history to build software — and AI’s flood into the mainstream has lifted all boats. It’s faster and cheaper than ever to build, market and sell new products — just executing quickly is not a differentiator anymore. You’re probably not the “first of” anything; or if you are, a competitor is likely not far behind, nipping at your heels.

We’d rather not add to the cacophony of voices echoing each other about how taste and craft are important. Instead, what we’ve found underexplored is discussions on operationalizing taste.

So, we mined the Review archives and the In Depth podcast airwaves for the best bits of advice we could find from folks at companies like Stripe, Square, Linear and Slack. As it turns out, at First Round we’ve been asking people about craft long before taste was taking over the zeitgeist. Here’s who we spoke to:

• Krithika Muthukumar, Stripe’s first marketing hire and former VP of Marketing at OpenAI
• Karri Saarinen, founder & CEO of Linear
• Alyssa Henry, former CEO of Square
• Milin Desai, CEO of Sentry
• Julie Supan, YouTube’s first Head of Marketing
• Anthony Casalena, CEO of Squarespace
• Noah Desai Weiss, former CPO of Slack
• Jiaona “JZ” Zhang, CPO of Linktree

And here’s a preview of some of the advice that's in store:

• Implement reviews at the 20% and 80% mark. Do not wait until a project is nearly out the door to review it. “At Stripe, we would do a 20% strategy review to make sure that we were aligned on the goals and intent of any big project. Then we would do an 80% review for the execution and check in on how things were going, like what the collateral looked like,” says Krithika Muthukumar, who was Stripe’s very first marketing hire. “It’s important that you review at the 80% mark, not the 99% mark because you still want the ability to make changes based on what comes up.”
• Test drive taste with a work trial. Probing for something as nuanced as taste can be exceptionally difficult in an interview setting. That’s why, before committing to any full-time hire, Linear has candidates complete a paid 2-5 day work trial, where they work with the team on a real project.
• Codify your product principles. To distill Slack founder Stewart Butterfield’s distinct product intuition throughout the rest of the company, Chief Product Officer Noah Desai Weiss instituted a set of product principles (like “don’t make me think” and “be a great host”). “They are all a bit simple and almost glib when you hear them, but when you unpack them, there’s a whole set of stories and examples around them. They created a shared language within the product org for not just our values, but how we apply those values in instances where it’s more subjective and about taste.”

Thanks, as always, for reading and sharing!

-The Review Editors

Recommended resources:

-Vercel's CEO Guillermo Rauch on building taste

-How to build your early marketing team (from Notion’s former CMO)

-4 questions for assessing new job fit

Today on The Review, we explore the human side of engineering orgs, with Apple engineering leader and veteran of Palantir and Slack, Michael Lopp.

Mastering the Human Side of Engineering: Lessons from Apple, Palantir and Slack

Even though it’s never been easier to create software, Michael Lopp — engineering leader at Apple and veteran of Palantir and Slack — still believes the center of exceptional engineering orgs are its people and their dynamics.

Good judgement. Incredible operations. Sound decision-making. “When I look at the last three companies I was at, they’re all completely different businesses,” Lopp says. “But they all shared the same ethos that prioritized engineering, rapid growth and smart people.”

In this exclusive interview, Lopp goes beyond the technical aspects of the engineering function, instead turning his attention to its people. He provides founders and managers with tactical advice for structuring their engineering org and how to get the most out of the people who comprise it.

1. Encourage “wolf time” — in Lopp’s ideal world, engineers split their time 71/29. 71% of the time is for doing the things they need to get done. The other 29% of the time is doing whatever is inspiring based on the 71% stuff.
2. Keep debate regular — specifically, debate between product, design and engineering. He believes companies give themselves the best chance at making sound decisions by having a steady stream of cross-org debate.
3. Build operational systems that can scale while maintaining quality — Lopp says having sound judgement and maintaining sound operations leads to creating and scaling good products.
4. How to foster the relationship between product and engineering teams — make sure PMs are telling the story of the “why” behind the product, and engineers understand that, so they can focus on the “how.”

Lopp also shares the traits he’s seen successful leaders possess across his career, from being malleable, to a good storyteller, to understanding individuals’ goals (so leaders can help them grow).

Whether you’re a new engineering manager or are seasoned in leading teams, Lopp’s insights are rooted in the ever-present, yet always-changing thing that powers your org — your people. Knowing what motivates them and how they work together is a vital component to the success of the engineering function and thus, your company.

As always, thanks for reading and sharing.

-The Review Editors