Senior Software Engineer - Frontend (Attack & User Emulation)

SimSpace Corporation

About The Position

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. SimSpace fosters a culture of continuous learning, curiosity, and professional growth. This 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. 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. 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.

Requirements

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.

Nice To Haves

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.

Responsibilities

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.