Second Believers In Each Other: A Decade-Long Collaboration with Justin Mares

Today is a big day for Truemed, one of the portfolio companies we get to collaborate with. Its founder and CEO, Justin Mares announced $34 million in Series A funding led by a16z (we got to participate as well).

Justin is one of the first founders I ever invested in. He was just starting out too. Fast forward, I've invested in several of Justin's businesses over the years. He is also a venture partner at Long Journey. It was hard to keep track of who was believing in whom anymore.

Justin and I at the Banister Freedom House before our annual Long Journey Casino Charity Poker Tournament.

This past spring, Justin and I almost jeopardized our decade-long relationship.

The specifics don't matter. But there was a moment where we were both willing to risk the relationship for principle. Both fighting for what we thought was fair.

We both chose the bigger future we saw as possible for one another (e.g. growing old together, doing many more things together) over the thing in front of us. We worked through it. And strangely, that conflict made us respect each other even more. It solidified something that had always been there but needed to be tested.

We found the win-win by really sticking to what mattered: collaboration over transaction.

Partnership isn't easy. But the ones worth having are the ones that survive the hard conversations.

What I Know To Be True About Justin

I first met Justin when he was selling bikes back and forth from Oakland to San Francisco. Not a bike shop. Just opportunity. Find mispriced bikes in Oakland, ride them to SF, sell them, take BART back, repeat.

First product run of Kettle & Fire.

Then he gave up bikes to boil chicken and beef bones. He was going to take leftover bones no one wanted, throw them in a kettle, and sell broth at Whole Foods for $10 a carton.

Most people told him to get a real job. I gave him a check.

Now Kettle & Fire has a facility the size of three football fields.

Justin is a fire starter. A momentum creator. He sees a small flame in a person and believes in how big it can become. He adds wood to it with support and belief.

He's a classic second believer.

His work at Long Journey is finding young people like him, people with that spark, and breathing belief into them. Showing them what's possible. He follows his own curiosity relentlessly. He's in every WhatsApp group about longevity, biohacking, optimization. And that curiosity leads him to the weirdest deals, which he brings to us, not because he's sourcing, but because he genuinely can't help but get excited about what people are building.

But beneath all that hustle and curiosity, Justin is deeply, genuinely joyful.

He loves his wife Janine and her adventurous spirit—how she gets him out on long bike rides, things he might not do on his own. One of my favorite images of Justin: riding his bike with Janine up a big hill in Marin, both of them pushing hard, both of them smiling.

This is a joyful man. And he can't help but want that for everyone. Health is the foundation for all of it.

That's why every company he builds comes back to enabling that: Kettle & Fire, Truemed… different vehicles, same mission.

Blank Check

In 2022, I did something I'd never done before: I printed out a term sheet and signed it with a pen.

We were at a Long Journey team retreat in Tahoe. Justin and I sat down together. As I handed him the physical paper for Truemed's pre-seed round (the first $900K), I told him: "This is the first of us investing $100 million-plus into Truemed."

At the time, our fund had raised less than $200 million total. I was committing more than half of everything we'd raised to a fintech company run by a soup company founder who wanted to use HSA funds for gym memberships.

It wasn't ceremony. It was certainty.

We're well on our way. We've since led the seed round. Truemed is now the largest investment across all our funds.

I've always said: whatever Justin's doing, I'll give him money.

Cyan once told me that collaboration is the highest form of love. That's what this is. Deep belief in one another. Trust in what we see as possible for each other. The certainty that both of us are going to keep doing bigger and bigger, greater things.

He'll tell me when he sees something off. I'll tell him when I see something better for him. We keep doing that for one another. Actually being in it together. Actually caring whether the other person succeeds.

On This Day…

I'm proud to continue supporting this mission as Justin scales Truemed.

I'm happy to be a second believer in him and am deeply grateful for his second believing in me as well on my own journey. The founder is always the first believer. They take the leap when the vision exists only in their mind. The second believer’s job is simple: recognize the fire and fan the flame.

I'd done it before with Kettle & Fire and Justin's other businesses. I knew his pattern. I knew that when he spots a misalignment, whether it's bikes or bones or HSA dollars, he has this uncanny ability to build a business around it that actually works.

So when he came to me with Truemed, I didn't need to overthink it. I printed out that term sheet in Tahoe and we signed right then and there.

It is truly a privilege to get to collaborate with Justin, over and over again, on bigger and bigger visions for the world.

Here's to the next chapter.