SimSpace serves as an AI Proving Ground where organizations can confidently train, test, and outmaneuver adversaries in any environment. Trusted by allied governments, militaries, enterprises, and research institutions worldwide, SimSpace enables adaptive, AI-ready defenses that stay ahead of evolving threats. Founded in 2015 by experts from U.S. Cyber Command and MIT Lincoln Laboratory, the platform unifies training, testing, and validation in a realistic, live-fire simulation—helping teams evaluate security investments, optimize performance, and compress cyber readiness cycles from months to days.

Why join SimSpace? We are an organization that is focused on building our culture and mindfully enhancing our atmosphere every day which is why we have collaborated on an integral value system. Our governing philosophy of being Human Centered is deeply embedded within our value system. We apply this philosophy to every one of our internal team members, external clients, and their customers.

How Do We Work? We believe that people are at the center of everything we do. SimSpace fosters a culture of continuous learning, curiosity, and professional growth. That belief shows up in action: in-house training, internal and external learning platforms, cyber conferences, industry events, and dedicated time for skill development. Our people are empowered to shape their careers - and it shows. Year over year, SimSpace consistently outperforms industry benchmarks in internal mobility, promotions, and total rewards growth.

Who Thrives Here? We are a team of innovators, protectors, and problem-solvers. We believe diversity of thought and experience fuels better solutions, and we’re committed to building teams that reflect the communities we serve. Whether you’re remote or office-based, you’ll collaborate with talented colleagues across departments and time zones, united by the mission to create a safer digital world.

We invite you to apply today!

We are looking for a Staff Software Engineer, Greyspace, to lead the technical design and development of a realistic, simulated internet for SimSpace cyber ranges. You will help build the services, networking, and operator workflows that make training environments believable, repeatable, and safely contained. The ideal candidate brings deep experience building distributed software systems, strong networking fundamentals, and the ability to turn ambiguous requirements into working software across team boundaries.

In this hands-on technical leadership role, you'll shape Greyspace's architecture and implementation with Product, Security, and engineering partners. You will write and review code, prove architectural decisions through working increments, and guide the project from early implementations to reliable operation. The focus is on building reusable simulated services with clear isolation boundaries and integrating them into the SimSpace platform. Specifically, this position will be responsible for:

• Greyspace service architecture, APIs, and orchestration for configuring and managing simulated internet environments

• Realistic network and application behavior, including DNS, TLS, web, and mail services

• Reusable services and content with isolated per-range configuration, identities, and mutable state

• Platform and range integrations, operator workflows, automated validation, and operational readiness

What will you be doing as a Staff Software Engineer, Greyspace at SimSpace?

• Lead Greyspace architecture and technical decisions, defining service boundaries, data ownership, API contracts, and failure behavior with partner teams.

• Design and build the services that configure, deploy, and manage simulated internet environments. Own critical implementation work and help turn prototypes into maintainable, tested software.

• Develop realistic network and application behavior across DNS, certificates, routing, and services such as web and mail. Validate complete workflows from a range host through the simulated service and back.

• Design for reuse across ranges while isolating configuration, credentials, mutable state, and faults. Work with Security and infrastructure partners to test containment and prevent unintended access between environments or to live networks.

• Define versioned integration contracts with platform, range, and emulation teams. Partner on operator workflows for configuration, readiness checks, troubleshooting, and lifecycle management.

• Partner with Product and technical leaders to translate training needs into prioritized use cases, explicit acceptance criteria, and incremental delivery plans.

• Lead scoping and estimation, making assumptions, dependencies, and trade-offs explicit. Break ambiguous work into useful milestones and validate high-risk decisions with focused technical proofs.

• Drive reliability and operational readiness through automated integration tests, observability, performance testing, recovery procedures, and deployment and upgrade validation for hosted and on-premises environments.

• Lead design and code reviews, resolve cross-service technical risks, and establish practical engineering standards that support reliable delivery.

• Mentor senior engineers through hands-on collaboration, sharing expertise in distributed systems, networking, testing, and technical decision-making.

Who you are:

• 8+ years' of experience and currently in the position of Staff or Senior Software Engineer with a strong record of building distributed applications, platform services, or networked systems and leading technically complex work across teams.

• Proven ability to design, build, and ship production-grade distributed services — comfortable owning the full software development lifecycle from architecture through delivery.

• Strong networking fundamentals, including TCP/IP, DNS, HTTP, and TLS, with hands-on experience diagnosing behavior across application, service, and network boundaries.

• Experience designing multi-tenant or distributed systems with clear isolation, state management, API, and failure-recovery boundaries. Familiarity with cyber ranges, simulation, or internet service infrastructure is a plus.

• Demonstrated ability to drive technical standards and architectural decisions across multiple teams, balancing idealism with pragmatic delivery.

• Strong scoping and estimation judgment: able to produce an early estimate, identify uncertainty and dependencies, and break a large initiative into testable milestones. Helps teams make commitments grounded in evidence and available capacity.

• Strong communicator who can explain complex architecture, networking behavior, and engineering trade-offs to technical and non-technical audiences.

• Proficient in a modern backend programming language and software engineering practices including API design, service decomposition, automated testing, code review, and CI/CD.

• Hands-on experience with Linux, containers, and Kubernetes, including deploying and troubleshooting services. Experience with self-hosted, on-premises, or disconnected environments is a strong plus.

• Comfortable operating with ambiguity — at the Staff level, the roadmap isn't always fully defined, and this role is expected to help shape it. We're looking for someone who drives clarity rather than waiting for it.

• Experience working in security-sensitive or compliance-driven environments (DoD, FedRAMP, SOC 2, or similar) is a strong plus.

We’re proud to offer a competitive and comprehensive package designed to support your well-being, growth, and success:

• Compensation. Base salary range: $185,000 - $260,000, reflecting our confidence in your expertise and impact, with the opportunity for annual bonuses tied to company performance and individual contributions.

• Health & Wellness. Comprehensive medical, dental, and vision benefits, plus savings plans—coverage starts on day one!

• Mental Health Support. Access to company-paid counseling, coaching, and resources for you and your family through Spring Health.

• Financial Well-Being. Plan for your future with a 401(k)-retirement savings plan featuring a company match.

• Flexible Time Off. Take the time you need with unlimited vacation and dedicated health & wellness days. SimSpace provides flexible solutions to meet the diverse work-life needs of team members.

• Parental Leave. Paid leave plans to support you and your loved ones during life’s most important moments.

• Ownership Opportunities: Equity stock options at hire, with annual performance-based grants—become an invested stakeholder in our shared success.

• Referral Rewards: Earn 1,500–3,500 for every qualified hire through our employee referral program.

• Peloton Interactive Wellness Program: Full- and partial- subsidized membership plans and equipment discounts to help you reach your personalized fitness goals.

• Continuous Learning: Access a LinkedIn Learning membership to prioritize your personal and professional development.

• Social Connections: Monthly reimbursements for meaningful connections with teammates through our SocialSpace Community.

• Extra Perks: Legal plan coverage, pet insurance, wellness reimbursements, and more to simplify life’s details.

SimSpace is an Equal Opportunity Employer:

In compliance with federal law, all persons hired will be required to verify identity and eligibility to work in the United States and to complete the required employment eligibility verification document form upon hire.

SimSpace is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, pregnancy, genetic information, disability, status as a protected veteran, or any other protected category under applicable federal, state, and local laws. We are committed to providing an inclusive and welcoming environment for all members of our staff, clients, volunteers, subcontractors, vendors, and clients.

Research shows that women and people from underrepresented groups only apply to jobs if they meet all of the qualifications. However, no one ever meets 100% of the qualifications. SimSpace encourages you to break that statistic and to apply. We look forward to your application!

We also consider qualified applicants regardless of criminal histories, in accordance with applicable law. We are committed to providing reasonable accommodations for qualified individuals with disabilities in our job application procedures. If you need assistance or accommodation due to a disability, please contact [email protected].

SimSpace does not accept unsolicited resumes from employment agencies.

Actual compensation for the position is based on a variety of factors, including, but not limited to affordability, skills, qualifications and experience, and may vary from the range.