Britt Espinosa — Snohomish, WA
World 01

Product & Tech

When I was about ten, my dad showed me how to make a slingshot. We grabbed a pair of clippers, hiked into the woods behind our house, and found a solid branch with a good Y in it. We cut it down, dug up some old leather and rubber, and spent the afternoon shooting cans.

Target practice was fun. But building the thing was my favorite part — so much so that when Dad said “let’s do slingshots” a few days later, I grabbed the clippers and headed for the door. I thought he meant we were building another one.

I’ve always loved the process of building, sometimes more than the finished thing. Here are a few of my favorite products.

01

CircuitSim

Co-founder · Design · Development · Sales & marketing

CircuitSim is a browser-based circuit simulator with a full SPICE engine — real analog simulation with nothing to install and no license server to wrestle with. Open a tab, wire up a circuit, and watch it behave the way it would on the bench.

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02

PauseBox

Founder · Hardware design · iOS development · Sales & marketing · Chief packer of shipments

PauseBox is a physical barrier to digital distraction. It started as a fun personal project, but demand from friends and family pushed me to redesign the hardware for a broader release. It’s still manufactured out of my house, and several thousand units have shipped to people all over the world. I’ve gotten very good at taping boxes shut and navigating the US Postal Service.

Learn more
03

Tulu Systems

Co-founder · Product management · Field operations · Sales & marketing

Tulu is a turnkey solution for monitoring commercial HVAC systems and overall building power consumption, helping buildings reduce HVAC operating costs by up to 75% and overall electrical energy consumption by 40%. As one third of the original co-founding team, I was involved in every aspect of the product — design, installation operations, go-to-market strategy, ERP integration, and our channel sales partner program.

04

Spotivibes

retired

Founder · Design · Development

Spotivibes started as a side project to help promote my band’s music to playlist curators. Spotify playlists are the modern equivalent of terrestrial radio — one of the few ways an independent artist can reach a huge audience for basically free. The hard part is finding playlists whose curators are active and open to submissions, which is slow, tedious work. The tool let me search and filter for exactly those. It turned out I wasn’t the only one who wanted it: more than 1,000 artists used it to promote their music, including several signed to major labels.

05

Ember

arriving early 2027

Founder · Hardware, software & firmware development

Ember is an upcoming ambient music tool in the form of a guitar pedal. As a musician, I was always frustrated that the most polished parts of a recorded performance — backing pads, textures, risers, drops — couldn’t be reproduced live. Ember makes it possible.