Backend Software Engineer (Internet Services Simulation)

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 Software Engineer to build and operate the simulated internet services layer of SimSpace's internet simulation platform. The network simulation layer handles routing and latency; this role handles the internet itself — deploying and operating a persistent catalog of simulated and real internet services (think: fake GitHub, fake social media, fake webmail, AWS, GCP, Azure, and dozens of real SaaS apps) that red and blue teams interact with. This is a creative and technically broad role that combines service deployment automation, content generation, and DNS and email infrastructure to produce an internet environment that is indistinguishable from the real thing at the application layer. The team is responsible for: A persistent catalog of simulated internet services including open-source self-hosted platforms (social media, file sharing, webmail, collaboration tools, and others) and custom services that approximate major internet properties Incorporate hooks to bring real internet SaaS applications seamlessly into the simulated internet Simulate and/or bridge to popular cloud services in AWS, GCP, Azure, and others Content seeding and web scraping pipelines that populate simulated services with realistic data — repositories, social posts, email threads, user activity — making them plausible to human operators and automated tooling alike External DNS infrastructure: the internet simulation platform is the authoritative resolver for all simulated public domains, with correctly configured mail, sender authentication, and domain registration records The email delivery boundary between the internet simulation platform and in-range mail infrastructure, enabling realistic and scenario-driven email including adversarial content for red team exercises Service lifecycle automation: deploying, configuring, and managing simulated services in response to range and scenario requirements What will you be doing as a Software Engineer, Internet Services Simulation at SimSpace? Design and operate the Kubernetes-based deployment automation for the simulated service catalog, including deployment configuration for each service type, health monitoring, and lifecycle management Build and maintain content seeding pipelines that scrape, transform, and inject realistic content into simulated services — making a fake code repository look like it has years of commit history, or a fake news site look like it has been publishing for months Own the external DNS layer: configure and operate authoritative DNS for all simulated domains, ensure correct mail and sender authentication records are generated at domain provisioning time, and maintain consistency between DNS state and deployed services Build and maintain the email delivery infrastructure that allows the internet simulation platform to send mail into range environments, including correct envelope construction, authentication headers, and support for adversarial email scenarios Collaborate with the identity and persona team to ensure simulated services are correctly provisioned with user accounts at persona registration time and that per-service user state remains consistent with the broader persona definition Instrument and monitor the simulated service catalog, building observability into service health and range-level activity using the platform's Grafana-based stack Contribute to the service API layer that allows other platform components and external orchestration systems to create and manage simulated services programmatically Our Tech Stack: Typescript, React, Postgres, Kotlin, Kubernetes, Spring Boot What are the qualifications to apply? To be successful as a Backend Software Engineer, Internet Services Simulation you need to have: Strong bilingual proficiency in English and Spanish skills required across written, virtual, and in-person interactions Solid experience deploying and operating containerized services in Kubernetes, including writing deployment configuration and automation for a heterogeneous set of applications Hands-on experience with self-hosted open-source platforms — you have run your own mail server, stood up a social media instance, or operated similar infrastructure and understand the configuration complexity involved Working knowledge of DNS — not just querying it, but operating authoritative nameservers, understanding zone delegation, and configuring records for email authentication Familiarity with email delivery infrastructure: how mail servers work, how sender authentication is constructed, and what makes an email appear legitimate to receiving infrastructure Experience with web scraping, data transformation pipelines, or content generation Comfort working across a broad, heterogeneous service catalog — this role rewards generalist depth across many technologies over deep specialization in one Familiarity with PKI and TLS fundamentals is a plus — understanding how certificate trust chains work and how clients are configured to trust custom certificate authorities Experience in cybersecurity, red team infrastructure, or cyber range environments is a plus We’re proud to offer a competitive and comprehensive package designed to support your well-being, growth, and success: Compensation. Base monthly pay range: 1,250,000 CRC - 2,250,000 CRC reflecting our confidence in your expertise and impact, with the opportunity for annual bonuses tied to company performance and individual contributions. Health & Wellness. Private medical, dental, vision, and life benefits. Mental Health Support. Access to company-paid counseling, coaching, and resources for you and your family through Spring Health. 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. 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. 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 View email address on click.appcast.io. 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.