About
A small company with a specific purpose.
Unspecified Software Co. is an independent software company founded by Clark and Carrie Sell. We build products that help people connect with each other, in ways that hold up over time.
01The name
“Unspecified” is what you call a thing before anyone decides what it's for.
We kept the name because it turned out to be honest. We've never been defined by one product, one platform, or one stack. We've shipped software used by millions of people and built communities that outgrew us. Today, all of it points at one thing: Troth.
What has never been unspecified is the reason. From the beginning, our mission has been to create software that connects people in a deeper, more meaningful way. It's still the test every project has to pass.
02How we work
Founder-owned. Founder-run. Nobody between you and the people who made the thing.
We write our own code. We answer our own email. We ship what we would want to use ourselves, and we build it with the people who are going to use it. When you write to Unspecified, one of us reads it.
03What we believe
Four things we won't trade away.
- 01
Private by design.
What's yours stays yours. Troth is end-to-end encrypted between two phones. No cloud, no AI, no company in the middle, including ours.
- 02
Small on purpose.
Unspecified is founder-owned and founder-run. The people making the decisions are the same people writing the code and answering the email.
- 03
Built to last.
We've spent decades shipping software and building communities. We would rather make something that still matters in ten years than something that trends this week.
- 04
Community, not audience.
An audience looks at you. A community looks at each other. Whether it's two people in a marriage or two thousand around a company, we build for the second one.
04Things we've built
Products, and the communities around them.
Troth
iOS · Coming 2026
A private, encrypted home for your marriage. The conversations, letters, memories, and promises two people are keeping, sealed between two iPhones.
jointroth.co
re/Human
Community practice
Our community-architecture practice: helping founders and teams design how the people around their business find each other, connect, and stay.
joinrehuman.com
THAT Conference
Founded by Clark
A family-friendly, community-run technology conference that grew into one of the largest of its kind in the United States.
thatconference.com
05The people
Clark and Carrie Sell.
FoundersClark Sell
Founder
More than 25 years building software, with engineering roles at Microsoft, Allstate, and Telerik along the way. Founded THAT Conference. Speaks regularly about building software, community, and the people side of both, and is available for keynotes and workshops.
Carrie Sell
Chief Operating Officer
Runs the business side of Unspecified and is building Troth alongside Clark. Together since 2000, married 23 years, which makes her the other half of the product's origin story.