Senior Software Engineer - Frontend (Attack & User Emulation)

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!

The Senior Frontend Software Engineer on the Attack & User Emulation team builds the primary control surfaces and dynamic visual interfaces that allow users to configure, simulate, and analyze cyber attacks and realistic user personas. This role exists to bridge complex backend simulation capabilities and real-time telemetry into high-quality, intuitive human-in-the-loop web applications.

Using React and TypeScript, you will lead the execution of frontend features, integrating cutting-edge capabilities like real-time data streaming and AI agent communication streams (such as Model Context Protocol servers). You will partner closely with UX Designers, Product Managers, and backend engineers to maintain a high bar for frontend performance, accessibility, and UI craft.

• Customer-facing control surfaces and simulation visualization interfaces for the range platform.

• Modern frontend architecture, dynamic topology components, and streaming UI workflows.

• Interface accessibility (WCAG), client-side performance, and frontend testing reliability.

• Frontend integration boundaries between core UI design systems and backend simulation APIs.

• Design, build, and maintain high-performance web applications using React and TypeScript.

• Lead end-to-end technical execution for frontend features, including real-time streaming displays (WebSockets, SSE) and AI/MCP integrations.

• Improve client-side performance, code reusability, testing coverage, and WCAG accessibility standards.

• Solve complex frontend challenges around visualizing large datasets, interactive network topology, and agentic workflows.

• Collaborate with UX Designers on feasibility and partner with backend engineers to define API contracts.

• Conduct thorough code reviews, champion frontend engineering standards, and mentor team members.

• By 30 days: Establish fluency in the application codebase, contribute to core React/TypeScript workflows, and deliver streaming interface features.

• By 60 days: Drive end-to-end technical delivery for a major simulation UI epic in partnership with Product, UX, and backend teams.

• By 90 days: Elevate team-wide UI quality, accessibility, and architectural standards across shared component ecosystems.

• 6+ years of professional experience building and shipping complex, scalable web applications.

• Deep expertise in React, TypeScript, modern state management, and web performance optimization.

• Experience integrating real-time data streams (WebSockets, SSE) and complex backend/AI protocols.

• Strong foundation in UI testing strategies (unit, integration, E2E) and accessibility (WCAG) standards.

• Proven ability to evaluate technical trade-offs between UX polish, performance, and delivery speed.

• Experience displaying ML/RL decisions, confidence metrics, or agentic behaviors in user interfaces.

• Familiarity with shared design systems (Storybook, Figma workflows) and complex data visualization libraries.

• Exposure to cybersecurity concepts, containerized development (Docker/Kubernetes), or CI/CD pipelines.

TypeScript, React, Monorail Design System, Storybook, Figma, WebSockets, SSE, Docker, Kubernetes, Git/GitHub

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.