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Code Metal is seeking a founding Staff Software Engineer in Test (SDET) for its Modeling & Simulation team, which builds a wargaming and decision-support platform for the U.S. Department of War. The platform combines backend APIs, asynchronous workers, geospatial and sensing models, authenticated multi-team play with fog of war, external simulation integrations, and emerging AI-assisted capabilities.
The role is hands-on and foundational: you will design and build the platform's automated validation system, defining which behaviors require deterministic verification, statistical or model-based evaluation, or human review. You will translate quality engineering strategy into a risk-based validation approach across unit, integration, contract, end-to-end, performance, resilience, and security-critical workflows.
Key responsibilities include:
- Building reliable test infrastructure (deterministic fixtures, isolated test data, service and event-contract tests, integration harnesses, versioned reference scenarios, deterministic replay, and focused browser automation).
- Improving CI feedback through test partitioning, parallel execution, caching, failure attribution, and flaky-test control.
- Writing behavior-focused tests for high-risk planning, sensing, simulation, authorization, state-transition, and recovery workflows.
- Partnering with simulation and model owners to turn intended behavior and known limitations into reusable reference scenarios, regression baselines, and reproducible quality evidence.
- Defining validation and release criteria for simulation and AI-assisted workflows, combining deterministic assertions, contracts, statistical evaluation, and appropriate human oversight.
- Establishing repeatable performance and reliability validation with measurable objectives.
- Participating in design and code reviews, identifying testability risks early, and mentoring engineers without becoming an approval bottleneck.
- Turning lessons from Modeling & Simulation into reusable quality bars and testing standards for the centralized Quality Engineering function.
This is a Staff-level individual contributor role with company-wide scope and influence. You will lead multi-team initiatives through influence and design documentation, not people management. You have turned quality strategy into test architecture for a product area and shipped the infrastructure and tests yourself.
REQUIREMENTS:
- Significant experience as an SDET, test-infrastructure engineer, quality architect, or software engineer responsible for automated validation of production systems.
- Strong production programming skills in Python.
- Deep experience building Python test infrastructure using pytest or comparable frameworks, including asynchronous testing, fixtures and factories, parallel execution, and CI integration.
- Demonstrated experience designing risk-based test strategies across multiple layers of a distributed system.
- Experience validating complex systems with partially nondeterministic behavior (simulation, statistical models, ML, or AI-assisted workflows) with sound judgment about deterministic checks, reference evidence, statistical evaluation, and human oversight.
- Hands-on experience testing Docker-based or comparable containerized, multi-service applications (APIs, databases, messaging, authentication, authorization, data isolation).
- Experience building and improving CI workflows with GitHub Actions or comparable platform, including test isolation, failure diagnosis, and flaky-test control.
- Ability to set technical direction, write design documents, mentor engineers, and lead multi-team initiatives through influence.
- Typically 8+ years of relevant software engineering, test infrastructure, or quality engineering experience, with demonstrated Staff-level scope and impact. Equivalent depth is valued over rigid year count.
PREFERRED QUALIFICATIONS:
- Experience validating simulation, geospatial, event-driven, or other stateful systems.
- Familiarity with testing or debugging C++ simulation or systems code.
- Experience testing TypeScript and React applications with Playwright or equivalent.
- Experience with performance testing, generated test data, and API or schema validation.
- Experience testing cloud-based, containerized systems using logs, metrics, traces, and retained test artifacts.
- Familiarity with constructive simulation, distributed simulation standards, or mission-analysis software.
- Hands-on experience evaluating AI-assisted or agentic systems, including tool-calling or multi-step workflows, and understanding risks such as nondeterminism, unsupported outputs, prompt or context manipulation, unsafe tool use, hidden state, and silent failure.
- Experience using AI coding assistants or agents throughout the software development lifecycle and defining quality controls for AI-assisted changes.
- Experience in a regulated, high-assurance, or mission-critical domain.
- Eligible to obtain and maintain a U.S. Secret security clearance.
