Software Engineer, Quality [SDET]

OneChronos is building the bazaar for agentic systems. We’re starting in capital markets, where our matching markets routinely account for more than 1% of notional U.S. equity market volume. By bringing together auction theory, distributed systems, artificial intelligence, and deep market structure expertise, we help humans and agents transact more efficiently, improve how value is allocated, and, ultimately, increase global GDP.

Our systems match billions of dollars in transactions daily on infrastructure where the margin for error is as thin as the markets demand. Our engineering team has scaled its output faster than most, and that growth has created a clear opportunity: to build a dedicated quality engineering function proactively - not as a response to problems, but as the natural next step for a team firing on all cylinders.

We rebuilt market structure from first principles. Help us build the quality platform that scales with it.

We're looking for someone to own quality as an engineering discipline. From test frameworks and CI/CD integrations to staging environments, simulation infrastructure, and automated validation, you'll build the systems that help engineers verify correctness before code reaches production. Your mission is to increase engineering velocity and confidence by making testing reliable, scalable, and easy to use across the organization.

About OneChronos ( OneChronos is a technology company of diverse thinkers innovating at the intersection of capital markets, mechanism design, and operations research, working to grow the global GDP by designing and operating matching markets leveraging advances in auction theory and artificial intelligence. Our software and systems are developed in house and match billions of dollars per day of security transactions.

What You'll Do

• Design, build, and maintain automated test frameworks and testing infrastructure across our trading platform, covering correctness, performance, and reliability.
• Develop tooling that enables engineering teams to test their own code more effectively, without creating bottlenecks.
• Define test strategies for new features and system changes in partnership with engineering, SRE, and DevOps teams.
• Build and own CI/CD pipeline integrations that gate deployments on meaningful quality signals.
• Build testing infrastructure and validation tooling that surfaces regressions and correctness issues before they reach production.
• Investigate test failures, quality gaps, and escaped defects, driving structural improvements to prevent recurrence.
• Participate in design and architecture reviews to identify testability gaps early.

Who You Are

• You write production-quality code and treat test infrastructure the same way -- not as scaffolding, but as software that needs to be maintained and improved.
• You have strong experience with test automation frameworks, testing infrastructure, and developer tooling, and have built or meaningfully extended one from scratch.
• You're fluent in at least one systems-oriented language (Rust, C++, Go, or Java) and at home in Python for scripting and tooling.
• You have worked in low-latency, high-throughput, or otherwise performance-sensitive environments and understand what it means to test at that layer.
• You think in edge cases. You're the person on the team who asks "but what happens if..."
• You work fluidly across organizational lines -- with SRE on reliability, with DevOps on deployment pipelines, with product engineers on correctness.
• Financial markets or trading systems experience is a plus, not a requirement. Curiosity about the domain is.

Compensation

Base salary range: $150,000 - $200,000, depending on experience, with eligibility for a discretionary annual bonus.