Principal Python Engineer (Modeling & Simulation)

About Code Metal Code Metal is the leader in automated software engineering you can trust. As AI writes more of the world's code, the bottleneck in software has shifted from writing code to verifying it works, and AI cannot verify its own work with certainty. Code Metal takes a fundamentally different approach: constrain AI to what it does reliably, verify every step independently of the model using formal methods, and keep engineers in the loop on the decisions that matter. The result isn't code that probably works — it's code that is provably correct, with auditable proof. Customers including the U.S. Air Force, L3Harris, RTX, and Toshiba use Code Metal to modernize legacy code, optimize performance on real hardware, and move prototypes to production, fast. Founded in 2023 with offices in Boston and San Francisco, Code Metal is funded by Accel, Salesforce Ventures, B Capital, Smith Point Capital, J2 Ventures, Shield Capital, Overmatch, RTX, and others. Learn more at codemetal.ai . Our Modeling & Simulation team is building the next-generation wargaming and decision-support platform that helps the DoW make multi-billion-dollar force-design decisions before those decisions are made in the real world. The team spans simulation and physics, backend and data systems, frontend and geospatial visualization, and AI systems, working together to turn operational questions into extensible, mission- and campaign-level simulations that government users can trust. In this role, you will help build the Python services, pipelines, and tooling that drive the core wargaming simulation. You will design backend services and APIs that interface with the frontend, integrate with multiple simulators, manage the data, and expose results to analysts, model developers, and government stakeholders. Scope of ownership, architectural authority, and mentorship responsibility scale with level — see “Level Expectations by Track” below. You'll develop the backend infrastructure that interfaces with agentic AI and machine learning pipelines to support platform, sensor, behavior, and decision models used across the simulation, while building extensible, well-tested foundations for the broader wargaming platform. You'll help design scenario-generation, Monte Carlo, sensitivity-analysis, and campaign-evaluation workflows, and build the distributed, cloud-scale infrastructure that lets simulations run across developer workstations, on-premises infrastructure, and cloud compute while preserving reproducibility and model provenance. Strong command of cloud services and distributed architectures is essential. About the role Design and implement backend services and APIs that orchestrate mission- and campaign-level simulation runs, collect their outputs, and expose results to analysts and government stakeholders. Build scenario-generation, operational and mission planning workflows, and key services for Monte-Carlo based sensitivity-analysis for our wargaming and decision-support platform. Build distributed, cloud-scale infrastructure that scales simulations across developer workstations, on-premises infrastructure, and cloud compute while preserving reproducibility and model provenance. Build data ingestion, normalization, and analysis pipelines that turn raw simulation output into decision-ready insight for defense users. Build scalable APIs (REST, GraphQL, gRPC) and containerized services that connect the Python tooling layer to the core simulation runtime and downstream analysis tools. Gather requirements from government stakeholders, domain experts, and analysts, and distill them into clear software designs. Employ strong SDLC practices throughout — code review, testing, continuous integration, release management, and build systems. Required Qualifications: Professional experience with collaborative, enterprise-level software development in Python, delivering products to a large customer base. Experience gathering requirements from stakeholders and distilling them into software designs. Experience building and delivering robust software using strong SDLC practices, including code review, testing, continuous integration, release management, and build systems. Familiarity with machine learning tools and frameworks. Expertise building scalable APIs (REST, GraphQL, gRPC). Hands-on experience with Docker and containerized application development. Eligible to obtain and maintain an active U.S. Top Secret security clearance. Preferred Qualifications: Familiarity with agentic AI frameworks and solutions. Familiarity with code analysis / static analysis. Experience working with cloud-based distributed systems (AWS, GCP, Azure). Active U.S. security clearance (Secret, Top Secret, or SCI/SAP). Direct experience developing AFSIM plugins, framework extensions, event infrastructure, or custom platform types. Familiarity with HLA, DIS, OneSAF, JSAF, NGTS, STK, or other constructive and distributed simulation environments. Experience supporting Air Force, Space Force, joint, or broader DoD acquisition and mission-analysis programs. Experience developing models for sensors, weapons, electronic warfare, jamming, communications, logistics, or command and control. Principal Level Expectations Years of Experience: 10+ Engineering Craft & Code Quality: Sets the quality and correctness bar across the department; their work is the example others learn from; improves the automated systems and practices that ensure quality department-wide. Architecture & Technical Knowledge: Provides architectural guidance across the department and invents paradigms that solve CodeMetal-specific domain problems (e.g., translation, optimization, deployment across target environments); a key resource on every major system. Delivery, Scoping & De-risking: A consistent contributor to the company's technical roadmap; gives reliable estimates for large cross-team initiatives; ensures pragmatic scoping toward the most valuable outcomes. Technical Leadership & Mentorship: An active driver of company-wide architectural reviews and proposals; mentors mid-level and senior staff at scale; influences others across departments toward the best technical outcome. Benefits Pay depends on experience, but we strive to be at the upper end of the salary range Health care plan with 100% premium coverage, including medical, dental, and vision 401k with 5% matching Paid Time Off (uncapped vacation, plus sick and public holidays) Flexible hybrid or remote work arrangement Relocation assistance for qualifying employees Wage Transparency - The salary range for this role is not a guarantee of compensation or salary, as the final offer amount may vary based on factors including, but not limited to, individual proficiency, skills, experience, and location. We are an equal opportunity employer. US Citizenship may be required for certain project assignments involving security clearance. Pursuant to the San Francisco Fair Chance Ordinance, we will consider for employment qualified applicants with arrest and conviction records.