ROXY SYSTEMS · SUBSTRATE ROLES OPEN

Build the Substrate, Not Just the App.

Roxy Systems designs and operates substrate-level infrastructure for identity, truth, time, and trust. We build systems where every change is witnessed, ordered, auditable, and coherent. If you think in invariants, flows, and guarantees, this is your kind of work.

Substrate Engineering
COSMOS & C-MOS
Evidence-Based Hiring
Auditability by Design

Roxy Systems

What we are building

Roxy Systems is a substrate company. We build the underlying machinery that lets organizations maintain coherent identity, ordered decisions, and verifiable history across time. Our core stack includes COSMOS and C-MOS — a commit and evidence layer that turns every change into a witnessed, auditable event.

Our work sits at the intersection of systems engineering, compliance, cryptographic guarantees, and organizational reality. We care about:

  • What must never break.
  • What must always be ordered.
  • What must always be provable.
  • What must always be explainable.
If you're drawn to the idea of a "substrate" — the layer beneath products, protocols, and teams — you'll recognize yourself in our work.

Who Thrives Here

You might be a fit if you:

  • Get excited when constraints reveal elegant solutions
  • Care more about correctness than being right
  • Read error messages before reacting
  • See compliance as a design challenge, not a checkbox
  • Think "what must be true" before "what could we build"

We hire for thinking, not credentials

No specific degree required. No years-of-experience threshold. We care how you move through real systems, not how you perform on contrived puzzles. If you can learn COSMOS and reason about guarantees, you can work here.

Four Tracks

Track A · The Invariant Thinker

For non-technical roles: PMs, operations, design partners who work closely with engineering. You'll internalize COSMOS, explain guarantees in plain language, and connect technical constraints to business reality.

Track B · The Builder

For engineers: You'll work in the Roxy Systems codebase, either shipping features in existing patterns (B1: Substrate Steward) or designing new primitives (B2: Substrate Inventor). We'll figure out together which path fits your strengths.

Track C · The Coherence Engineer

For legal & compliance: You'll design systems where compliance isn't documentation—it's structure. Where audit trails aren't evidence of truth, they ARE truth. You'll work directly with COSMOS, C-MOS, and Volta to architect legal guarantees as substrate primitives.

Track D · The Research Translator (Internship, 6 months)

For researchers transitioning to systems work: You've spent years on hard problems that required rigorous mathematical thinking. Now you want to see if substrate engineering is the right next step. You'll learn COSMOS deeply, contribute to real primitives, and discover whether you think like a substrate engineer. (Email us! hello[at] roxy.systems)

This track is for people within 2 years of completing deep research work who are exploring engineering as a career path. No prior production engineering experience required—we'll teach you. What matters: can you transfer your research rigor to substrate thinking?

Unsure which track? Apply anyway. The interview will reveal your strengths. Many candidates come in for one track and realize they're better suited for another.

The Interview Prerequisite

24–48 Hours of Substrate Immersion

We don't use standard take-home tests. Instead, all candidates receive 24–48 hours of early access to COSMOS documentation and onboarding materials before the first technical session.

This isn't a memorization test. We're looking for your ability to learn our unique substrate and apply its guarantees to new problems. During the interview, you'll use COSMOS in real scenarios.

The bottom line

If you read COSMOS with genuine curiosity and engage with its constraints honestly, you'll do well. We're not testing trivia—we're seeing how you think when learning something new.

Our Process

Real work. Observable behavior. Evidence-based decisions.

Track A · Invariant Thinker (2 hours)

Part 1 · 15 minutes
Quick verification you understood the prep materials. Comprehension, not memorization.
Part 2 · 60 minutes
Complete COSMOS onboarding together. You drive, we observe how you learn and problem-solve.
Part 3 · 30 minutes
Explain COSMOS concepts, analyze guarantees, respond to real scenarios.

Track B · Builder (5-6 hours, split across sessions)

Path B1 (Steward): Ship a real feature. We watch how you navigate unfamiliar code.

Path B2 (Inventor): Design a better primitive. We pair on unsolved problems in COSMOS.

Both paths are rigorous and evidence-based. We'll determine together which fits your strengths.

Track C · Coherence Engineer (3.5 hours + Second Round)

First Round: Translate regulatory scenarios into substrate constraints.

Second Round: Pair with a senior engineer on a real unsolved compliance problem.

All interviews are recorded and scored against explicit rubrics. You'll receive detailed feedback either way. We optimize for fairness and transparency.

How We Evaluate

We measure candidates against objective thresholds, not against each other. Every candidate is scored on the same rubric. This transparency helps you know exactly what we're looking for.

Track A · Invariant Thinker (100 points)

Strong Hire
85–100
Hire
70–84
Marginal
55–69
No Hire
0–54

Track B1 · Substrate Steward (210 points)

Strong Hire
170–210
Hire
140–169
Marginal
105–139
No Hire
0–104

Track B2 · Substrate Inventor (Qualitative)

No point system for inventors. We ask: "Did they make us think differently about our own system?"

Must-Haves (Binary)
  • Deep expertise in something hard (distributed systems, protocol design, symmetry theory, invariant lattice structures, data transformation, cryptography, formal methods, etc.)
  • Intellectual honesty (admits uncertainty, updates beliefs)
  • Systems thinking (reasons about invariants, not just features)
The Real Test

"If this person worked on COSMOS for a month, would they discover a flaw we didn't know existed, or invent a primitive that makes the whole system better?"

Track C · Coherence Engineer (100 points)

Strong Hire
85–100
Hire
70–84
Marginal
55–69
No Hire
0–54

What These Scores Measure

Across all tracks, scoring reflects:

  • Structural understanding: Do you grasp why COSMOS is built this way?
  • Transfer intelligence: Can you apply substrate thinking to new problems?
  • Intellectual honesty: Do you engage genuinely or try to perform?
  • System integrity: Do you care about correctness over ego?

Marginal candidates get a second look

If you score in the marginal range, a senior team member independently reviews your full recording. We want to catch potential we might have missed. Both reviewers discuss before any decision. We'd rather leave a role unfilled than compromise—but we also work hard to identify talent in unconventional candidates.

What We Value

Curiosity without ego

You ask questions to understand, not to prove you're smart. You update your beliefs when you learn something new. You care more about getting it right than being right.

Calm under uncertainty

You read error messages carefully. You debug systematically. You stay composed when something doesn't work the first time. You ask precise questions instead of flailing.

Directness without cruelty

You communicate clearly and honestly. You give feedback that helps people improve. You hold high standards while treating everyone with dignity.

We're building systems that people will rely on when things go wrong. We need people who take that responsibility seriously—and who help others do their best work.

This Isn't For Everyone

You probably won't thrive here if you:

  • Prefer moving fast over getting it right
  • See constraints as obstacles to work around
  • Want to "just ship" without understanding why
  • Treat compliance as bureaucracy instead of design
  • Need to be the smartest person in the room

That's okay. Substrate work requires a specific temperament. Better to know now than six months in.

Apply to Roxy Systems

This form is intentionally specific. It helps us understand how you think and whether substrate work is right for you. Take your time with it.

We review every application carefully

If there's a potential fit, we'll reach out with next steps and COSMOS onboarding details. If not, we'll tell you why. Either way, you'll hear back within two weeks.