Tracer emerges from stealth with $25M seed to build the first subterranean defense tech company

Tracer emerges from stealth with $25M seed

Yadin Soffer's bet is that underground is the one domain in defense that nobody has seriously addressed. Tracer, which came out of stealth last week, is positioning itself as the first company focused entirely on subterranean defense — what Soffer calls the "subterra" category, a term he coined and says has already gained traction on X.

The company's engineering team comes from The Boring Company and SpaceX, and the core product concept is a small-diameter autonomous underground vehicle capable of inserting payloads beneath the surface. The design logic follows a principle Soffer endorses: diameter is expensive, length is free. A narrow vehicle doesn't need to extract dirt — it can compress soil to the sides — which eliminates the bentonite mixing and surface logistics that make large-bore boring operations sprawling and expensive. The vehicle can trail essentially unlimited length of sensors, effects, or other payload behind it.

The military application Soffer describes most concretely is non-kinetic infrastructure disruption. DARPA recently issued an RFI seeking new methods to induce collapse in underground facilities using shockwave techniques. Tracer's vehicle would allow special forces to insert a payload underground and detonate it in a sequence designed to bring down buried infrastructure — facilities like those in Iran, Soffer says — without an air-dropped munition. The pitch is that existing penetration munitions, which rely on air delivery, aren't meeting the military's needs for this class of target.

“Tracer is the first of its kind subterra defense tech company. Subterra refers to everything in the subterranean defense domain — everything at the intersection between military applications for things that happen beneath our feet. Most of the focus right now is working with DC, working with the military, and establishing the subterra doctrine — the US subterra strategy for winning wars underground. The dream is someday a train that forges its own path and carries behind it essentially infinite payload — miles and miles of sensors and effects.”

The $25M and what it's actually for

The $25M seed round isn't primarily funding a large R&D team or heavy CapEx, at least not yet. Soffer says most of the near-term focus is on working with Washington and the military to establish subterranean operations as a recognized defense category — what he calls a "subterra doctrine" — and to win access to large government prototyping budgets. Those prototyping contracts would then fund the longer-cycle hardware development.

There is no existing program of record Tracer can plug into. The line items closest to this work, Soffer says, are buried inside other budget categories. The commercial thesis is that recognition precedes procurement, and the seed capital buys the time to create the category before competing for it.

The hardest technical problem, according to Soffer, isn't propulsion or payload — it's geological uncertainty. Unlike aerospace, where the forces acting on a vehicle are well understood, underground vehicles encounter unpredictable compositions. Hard rock can appear without warning, requiring either precise maneuvering or a cutter head swap. That uncertainty, more than anything else, is what makes the domain genuinely difficult.