Senior Platform Engineer

Senior Platform Engineer

Xcimer Energy leverages decades of research on Inertial Fusion Energy (IFE) combined with groundbreaking new laser architecture. Our mission is to deploy fusion power plants to meet global decarbonization goals as fast as possible. Xcimer has assembled a team of leaders in tough tech, fusion science, and manufacturing with a track record of rapid execution. Supported by leading investors, Xcimer is uniquely positioned to deliver limitless, clean, fusion power to combat climate change.

Join us in powering a better world with inertial fusion!

This is a full-time, onsite role based at our headquarters in Denver, CO.

As a Senior Platform Engineer you will design and ship the systems, services, and paved-path tooling that let researchers and engineers move fast. The platform spans data analysis pipelines, the data warehouse, dashboards, research code environments, and the friendly interfaces that expose HPC simulation to non-specialists: a broad surface where great engineering directly accelerates discovery.

This is a hands-on, high-impact role. You will architect and write systems, treat internal tooling as a product with real users, mentor junior engineers, and make deliberate tradeoffs between speed and robustness in an R&D environment where both matter. You'll work closely with physicists, controls engineers, and software architects to turn hard research problems into reliable, reusable infrastructure.

In this role, you will build the platform behind Xcimer's path to commercially viable inertial fusion energy. You'll let PhDs and engineers spend their time on physics and engineering instead of infrastructure, with direct access to simulation, data, and analysis through tools that work reliably. Every researcher's productive day depends on the platform you build. This is a strategic leadership position tied directly to the company's mission.

We are looking for our engineers to apply their technical expertise, problem solving skills, and dedication to quality to positively impact the future of energy!

Responsibilities

Internal Developer Platform

• Build and own the internal developer platform as a product, so researchers and engineers can provision what they need and start work quickly.
• Design and build the services behind data analysis pipelines, the data warehouse, dashboards, research code environments, and the web apps that expose HPC simulation to non-specialists.
• Extend Open OnDemand and related portals, and build what's missing where off-the-shelf tools fall short.
• Own AI developer tooling, its budget, and provisioning workflows.
• Set and maintain standards that give engineers autonomy while keeping the platform coherent and governable.

Systems & Software Engineering

• Architect and write platform services, control planes, APIs, and data-pipeline frameworks.
• Build reusable components and set software standards that match the needs of active R&D projects.
• Translate requirements from Physics, Engineering, and Controls teams into systems that scale and stay maintainable.
• Treat reliability, observability, and cost as design requirements.

HPC & Infrastructure

• Provide the platform layer over HPC clusters, job scheduling, and distributed file systems so researchers can run simulation and analysis themselves.
• Build and maintain secure cloud infrastructure (AWS/GCP/Azure), managed as infrastructure-as-code.
• Build observability, alerting, and incident-response systems across on-prem and cloud resources.
• Manage cloud costs proactively through architecture choices, reserved capacity, and observability.
• Lead migrations, upgrades, and modernization with minimal disruption to active experiments.

Documentation & Mentorship

• Write clear documentation, runbooks, and operational procedures so others can operate and extend the platform.
• Mentor junior platform engineers and the cross-functional engineers who build on the platform.
• Set technical direction for infrastructure as code, observability, and system resilience.

Qualifications

• Bachelor's degree in Computer Science, Engineering, Physics, Applied Mathematics, or related field; advanced degree preferred.
• 7+ years of experience in platform, infrastructure, or software engineering, including building internal tools or platforms used by other engineers.
• Strong software engineering fundamentals. Proficiency in Python, Rust, and/or C++.
• Experience building internal platforms or tooling that measurably improved team productivity.
• Hands-on experience with Linux and infrastructure automation (Ansible, Terraform, or equivalent).
• Experience with cloud infrastructure (AWS/GCP/Azure). Familiarity with HPC clusters and job scheduling is a plus.
• A track record of designing systems for reliability, observability, and scale.
• Experience with containerization and orchestration (Kubernetes, Docker, or similar).
• Experience mentoring engineers and leading cross-functional projects.
• Clear communication, including explaining technical tradeoffs to non-technical colleagues.
• Must be a U.S. citizen or national,…